scholarly journals The IL-2/IL-15 Mimetic NL-201 Prevents Myeloma Relapse after ASCT By Expanding Highly Cytolytic T Cells in the Bone Marrow That Are Resistant to Exhaustion

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 1609-1609
Author(s):  
Simone A Minnie ◽  
Nicole S Nemychenkov ◽  
Shuichiro Takahashi ◽  
Christine R Schmidt ◽  
Samuel RW Legg ◽  
...  

Abstract Multiple myeloma (MM) is a bone marrow (BM) resident hematological malignancy that is becoming increasingly recognized as one amenable to immunotherapy, although no therapies have yet provided durable, long-term disease control. Autologous stem cell transplantation (ASCT), the standard of care in eligible patients, provides a window for intervention with immunotherapy due to the induction of inflammation in the context of lymphodepletion at a time where there is also minimal residual disease and a disrupted tumor microenvironment (TME). We have previously established that the addition of T cells to BM grafts results in enhanced long-term myeloma control post-transplant in mice. Novel approaches aimed at improving and/or expanding the endogenous T cell response early post-ASCT may therefore prove highly effective with the benefit of avoiding ex vivo processing associated with other cellular therapies. To explore this, we utilized the IL-2/IL-15 mimetic NL-201: a de novo cytokine mimetic that signals via the beta and gamma subunits of the IL-2 receptor without engaging IL-2Rα (CD25). In pre-clinical studies, NL-201 has demonstrated the ability to signal to effector CD4 and CD8 T cells while avoiding the toxicity usually associated with IL-2 signaling via IL-2Rα. We hypothesized that NL-201 would enhance control of myeloma progression by stimulating T cell proliferation and activation early post-ASCT. We transplanted lethally irradiated Vk*MYC myeloma-bearing B6 recipients with BM and T cells graft from B6 donors and administered NL-201 from D+7 to week 6 (225 μg/kg weekly I.P). NL-201 promoted potent anti-myeloma immunity that was dependent on CD4 and CD8 T cells, but not NK cells (median survival was 68 days for control mice, unreached at >120 days for NL-201 alone or with NK depletion, 86 days for NL-201 with CD8 depletion, and 74 days with CD4 depletion; PBS vs NL-201 p<0.01; PBS vs NL-201 + αNK1.1 p<0.01; NL-201 vs NL-201 + αCD4 or αCD8 p<0.05). To further elucidate potential mechanisms of action we harvested BM from PBS and NL-201-treated mice 2 days after the last dose was administered and performed comprehensive immunophenotyping with high parameter flow cytometry. We grouped recipients based on whether they had controlled myeloma (MM-controlled) or had active disease progression at the time of harvest (MM-relapsed) to reveal immunological phenotypes that were dependent and independent of myeloma in the TME. In these experiments, all NL-201-treated recipients had controlled myeloma at time of harvest. Mechanistically, NL-201 significantly expanded the total number of CD8 T cells in the BM compared to PBS-treated mice with controlled or relapsed MM (PBS-treated mean CD8 T cell number was 1.0 x 10 5/femur vs 7.7 x 10 5/femur in NL-201-treated mice) but did not impact CD8 T cell number in peripheral blood. Memory CD8 T cells (CD44+CD62L+) were preferentially expanded, while the frequency of exhausted CD8 T cells (TOX +PD-1 +TIGIT +CD39 +; T EX) was reduced in NL-201-treated mice compared to both PBS-treated MM-relapsed and MM-controlled mice (75% T EX in PBS MM-relapsed, 15% PBS MM-controlled, 2% in NL-201; p<0.001). Surprisingly, >80% of the memory CD8 T cells in NL-201-treated mice produced granzyme B compared to <10% in PBS-treated mice. Granzyme B production was also observed in conventional CD4 T cells in response to NL-201 treatment, and the frequency of regulatory T cells was reduced by 50% after NL-201 compared to PBS MM-controlled and MM-relapsed mice (p<0.001). NL-201 expanded bone marrow resident cytotoxic memory CD8 and CD4 T cells that are resistant to exhaustion, whilst reducing the frequency of regulatory T cells in the BM TME. Together, these data highlight the promising therapeutic potential of NL-201 in multiple myeloma and support testing NL-201 in clinical trials for the treatment of hematological malignancies. Disclosures Hill: NapaJen Pharma: Consultancy; Roche: Research Funding; Syndax Pharmaceuticals: Research Funding; iTeos Therapeutics: Consultancy, Research Funding; Applied Molecular Transport: Research Funding; Compass Therapeutics: Research Funding; NeoLeukin Therapeutics: Consultancy; Generon Corporation: Consultancy.

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 328-328
Author(s):  
Simone A Minnie ◽  
Nicole S Nemychenkov ◽  
Kathleen S Ensbey ◽  
Christine R Schmidt ◽  
Gregory Driessens ◽  
...  

Abstract Multiple myeloma is a largely incurable bone marrow (BM) resident plasma cell malignancy that is increasing in incidence. Autologous stem cell transplantation (ASCT) is the current standard consolidation therapy and a subset of patients achieve durable progression free survival that is suggestive of long-term immune control. Utilizing novel preclinical models, we have provided definitive evidence that this is largely mediated by T cell-dependent myeloma-specific immunity. In both patients and preclinical models, myeloma progression is associated with T cell dysfunction and expression of multiple inhibitory receptors suggesting a loss of immunosurveillance. In mice, we have demonstrated potent anti-myeloma efficacy of TIGIT blockade in both ASCT and non-transplant settings. Here we utilized identical TIGIT Abs that do or do not Fc bind to demonstrate that immunological efficacy after ASCT was absolutely dependent on ADCC (median survival was unreached (>110 days) in Fc-binding vs 73 days in Fc-dead and 71 days in control Ig (cIg)-treated mice). Since TIGIT inhibition does not protect against myeloma relapse in all mice, it is apparent that combinational approaches are required to target non-responders. Therefore, we hypothesized that TIGIT blockade could be combined with immunomodulatory drugs (IMiDs) to provide synergistic anti-myeloma activity after ASCT. To that end, we utilized CRBN transgenic mice to investigate the efficacy of TIGIT blockade in combination with lenalidomide, the standard of care IMiD used in maintenance therapy after clinical ASCT. Briefly, B6 Vk*MYC myeloma-bearing (MM-bearing) mice were lethally irradiated and transplanted with B6 bone marrow (BM) and a suboptimal dose of T cells followed by anti-TIGIT or control Ig (100 mg twice weekly) for 5 weeks with lenalidomide (50 mg/kg daily gavage) or control diluent from D+14 for 3 weeks (Figure 1A). The combination of anti-TIGIT and lenalidomide provided synergistic anti-myeloma efficacy evidenced by prolonged median survival (109 days in combination vs < 60 days in monotherapy/control-treated mice, p<0.01; Figure B). Myeloma M bands were also suppressed in the combination treated mice relative to monotherapy or cIg-treated mice (p<0.01; Figure 1). Analysis of BM CD8 T cells 6 weeks after ASCT demonstrated that combination therapy significantly decreased terminal exhaustion (TOX + TIM3 + CD101 + PD-1 + DNAM-1 ─) with an average of only 20% of CD8 T cells with an exhausted phenotype in the combination group compared to greater than 50% exhausted CD8 T cells in monotherapy or cIg-treated mice (p<0.05; Figure 1C-D). The combination also increased the frequency of central memory and tissue-resident memory subsets (CD49b +CD69 +; p<0.05; Figure 1C-D), and increased IFNγ production from activated (PD-1 +; p<0.05; Figure 1E) cells compared to monotherapy or control Ig-treated mice. Importantly, these phenotypic changes were specific to the BM tumor microenvironment as we observed no effect of combination or monotherapy treatment on CD8 or CD4 T cells in peripheral blood. In sum, these data provide a strong rationale for combining TIGIT inhibition with immunomodulatory drugs to prevent the progression of myeloma. Figure 1 Figure 1. Disclosures Driessens: iTeos Therapeutics: Current Employment, Current equity holder in publicly-traded company. Holmberg: Up-To-Date: Patents & Royalties; Bristol Myers Squibb: Research Funding; Janssen: Research Funding; Merck: Research Funding; Millennium-Takeda: Research Funding; Sanofi: Research Funding; Seattle Genetics: Research Funding. Hill: NeoLeukin Therapeutics: Consultancy; Compass Therapeutics: Research Funding; NapaJen Pharma: Consultancy; Generon Corporation: Consultancy; Roche: Research Funding; iTeos Therapeutics: Consultancy, Research Funding; Syndax Pharmaceuticals: Research Funding; Applied Molecular Transport: Research Funding.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 4819-4819
Author(s):  
Monzr M. Al Malki ◽  
Sumithira Vasu ◽  
Dipenkumar Modi ◽  
Miguel-Angel Perales ◽  
Lucy Y Ghoda ◽  
...  

Abstract Patients who relapse after allogeneic HCT have a poor prognosis and few effective treatment options. Responses to salvage therapy with donor lymphocyte infusions (DLI) are driven by a graft versus leukemia (GvL) effect. However, relapses and moderate to severe graft versus host disease (GVHD) are common. Therapies that increase the GvL effect without inducing GVHD are needed. The NEXI-001 study is a prospective, multicenter, open-label phase 1/2 trial designed to characterize the safety, immunogenic, and antitumor activity of the NEXI-001 antigen specific T-cell product. This product is a donor-derived non-genetically engineered therapy that consists of populations of CD8+ T cells that recognize HLA 02.01-restricted peptides from the WT1, PRAME, and Cyclin A1 antigens. These T cells consist of populations with key memory phenotypes, including stem-like memory, central memory, and effector memory cells, with a low proportion (<5%) of potentially allogeneic-reactive T-naïve cells. Patients enrolled into the first cohort of the dose escalation phase received a single infusion of 50 million (M) to 100M cells of the NEXI-001 product. Bridging anti-AML treatment was permitted during the manufacture of the cellular product with a wash-out period of at least 14 days prior to lymphodepletion (LD) chemotherapy (intravenous fludarabine 30 mg/m 2 and cyclophosphamide 300 mg/m 2) that was administered on Days -5, -4, and -3 prior to the infusion of the NEXI-001 product up to 72 hours later (Day1). Lymphocyte recovery to baseline levels occurred as early as three days after the NEXI-001 product infusion with robust CD4 and CD8 T cell reconstitution after LD chemotherapy. NEXI-001 antigen specific T cells were detectable in peripheral blood (PB) by multimer staining and were found to proliferate over time and to traffic to bone marrow. The phenotype composition of detectable antigen specific T cells at both sites was that of the infused product. T-cell receptor (TCR) sequencing assays revealed T cell clones in the NEXI-001 product that were not detected in PB of patients tested at baseline. These unique clones subsequently expanded in PB and bone marrow (BM) and persisted over time. Neutrophil recovery, decreased transfusion burden of platelets and red blood cells, and increased donor chimerism were observed. Decreases in myeloblasts and reduction in the size of an extramedullary myeloid sarcoma were suggestive of clinical activity. One patient, a 23-year- old with MRD+ disease at baseline, received two doses of 200M NEXI-001 cells separated by approximately 2 months. Following the first infusion, antigen specific CD8+ T cells increased gradually in PB to 9% of the total CD3+ T cell population just prior to the second infusion and were found to have trafficked to bone marrow. By Day 2 following the second infusion, which was not preceded by LD chemotherapy, the antigen specific CD8+ T cells again increased to 9% of the total CD3+ T cell population in PB and remained at ≥5% until the end of study visit a month later. The absolute lymphocyte count increased by 50% highlighting continued expansion of the NEXI-001 T cells. These cells also maintained significant Tscm populations. Treatment related adverse events, including infusion reactions, GVHD, CRS, and neurotoxicity (ICANS), have not developed in these patients who have received 50M to 200M T cells of the NEXI-001 product either as single or repeat infusions. In conclusion, these results show that infusion of the NEXI-001 product is safe and capable of generating a cell-mediated immune response with early signs of clinical activity. A second infusion is associated with increasing the level of antigen specific CD8+ T cells and their persistence in PB and BM. TCR sequencing and RNA Seq transcriptional profiling of the CD8+ T cells are planned, and these data will be available for presentation during the ASH conference. At least two cycles of 200M NEXI-001 cells weekly x 3 weeks of a 4-week cycle is planned for the next dose-escalation cohort. Early data suggest that the NEXI-001 product has the potential to enhance a GvL effect with minimal GVHD-associated toxicities. Disclosures Al Malki: Jazz Pharmaceuticals, Inc.: Consultancy; Neximmune: Consultancy; Hansa Biopharma: Consultancy; CareDx: Consultancy; Rigel Pharma: Consultancy. Vasu: Boehringer Ingelheim: Other: Travel support; Seattle Genetics: Other: travel support; Kiadis, Inc.: Research Funding; Omeros, Inc.: Membership on an entity's Board of Directors or advisory committees. Modi: MorphoSys: Membership on an entity's Board of Directors or advisory committees; Seagen: Membership on an entity's Board of Directors or advisory committees; Genentech: Research Funding. Perales: Sellas Life Sciences: Honoraria; Novartis: Honoraria, Other; Omeros: Honoraria; Merck: Honoraria; Takeda: Honoraria; Karyopharm: Honoraria; Incyte: Honoraria, Other; Equilium: Honoraria; MorphoSys: Honoraria; Kite/Gilead: Honoraria, Other; Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; Medigene: Honoraria; NexImmune: Honoraria; Cidara: Honoraria; Nektar Therapeutics: Honoraria, Other; Servier: Honoraria; Miltenyi Biotec: Honoraria, Other. Edavana: Neximmune, Inc: Current Employment. Lu: Neximmune, Inc: Current Employment. Kim: Neximmune, Inc: Current Employment. Suarez: Neximmune, Inc: Current Employment. Oelke: Neximmune, Inc: Current Employment. Bednarik: Neximmune, Inc: Current Employment. Knight: Neximmune, Inc: Current Employment. Varela: Kite: Speakers Bureau; Nexlmmune: Current equity holder in publicly-traded company, Honoraria, Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3953-3953
Author(s):  
Amy Guillaumet-Adkins ◽  
Praveen Anand ◽  
Huiyoung Yun ◽  
Yotam Drier ◽  
Anna Rogers ◽  
...  

Introduction: Early T-cell precursor acute lymphoblastic leukemia (ETP T-ALL) is a distinct subtype of T-ALL characterized by higher rates of relapse and induction failure. Large-scale genetic sequencing studies have identified frequently mutated oncogenes and gene fusions in ETP T-ALL, while bulk transcriptome analyses have revealed expression features resembling myeloid precursors and myeloid malignancies. However, the contributions of intra-tumoral functional heterogeneity and microenvironment to tumor biology and treatment failure remain unknown. Methods: We performed full-length single-cell RNA-sequencing of 5,077 malignant and normal immune cells from bone marrow or blood from five patients with relapsed/refractory ETP T-ALL (based on immunophenotyping, all with NOTCH1 mutations), before and after targeted therapy against NOTCH1. These patients were enrolled on a phase I trial with the γ-secretase inhibitor (GSI) BMS-906024 (NCT01363817). Expression of selected genes was validated by RT-PCR, flow cytometry and immunohistochemistry. Results: Single cell transcriptome analyses revealed a deranged developmental hierarchy characterized by co-expression of stemness programs in multiple malignant cells implying ineffectual commitment to either lymphoid or myeloid lineage. Most ETP T-ALL cells co-expressed HSC (hematopoietic stem cell), CMP (common myeloid progenitor) and CLP (common lymphoid progenitor) signatures simultaneously (Pearson correlation: CLP-CMP: R= 0.41, p < 2.2e-16; HSC-CLP: R= 0.53; p < 2.2e-16; HSC-CMP: R = 0.39, p <2.2e-16). Only a fraction of cells (less than 15%) demonstrated mutually exclusive CLP or HSC signatures. In contrast, CLP, CMP and HSC signatures were not co-expressed and always negatively correlated in normal bone marrow cells (CLP-CMP: R= -0.11, p < 2.2e-16; HSC-CLP: R= -0.38; p < 2.2e-16; HSC-CMP: R = -0.67, p <2.2e-16). Direct targeting of NOTCH1 as the driving oncogene has shown disappointing results in the clinical setting due to the rapid development of resistance. PI3K activation has been shown as a genetic mechanism of Notch resistance, however it is unclear if transcriptional rewiring can give rise to PI3K dependent cells after Notch inhibition. To address this question, we predicted the activity of signaling pathways in single cells after Notch inhibitor treatment using PROGENy. Most single cells demonstrated loss of Notch signaling. PI3K signaling activity was the most anti-correlated signaling pathway to Notch signaling (Pearson correlation: R= -0.51, p < 2.2e-16). Of note, this population preexisted at a frequency of ~30% in the untreated population, coexisting with cells with high Notch activation. Analysis of the immune microenvironment revealed an oligoclonal T-cell population in ETP T-ALL compared to normal donor T-cells. CD8+ T-cells from ETP patients expressed markers of T-cell exhaustion (PDCD1, TIGIT, LAG3, HAVCR2). Analyses of expression levels of the respective ligands on leukemic blasts and the predicted interaction with their receptors on endogenous CD8+ T-cells demonstrated the highest interaction score between HAVCR2 and its ligand LGALS9. LGALS9 was universally expressed in all leukemic cells, which was confirmed by flow cytometry staining in leukemic blasts and IHC staining in bone marrow of 8 patients with ETP T-ALL and 7 patients with T-ALL. T-ALL supernatant increased expression levels of the exhaustion markers HAVCR2,TIGIT and decreased effector marker GZMB in polyclonal activated normal donor CD8+ T-cells (RT-PCR). This effect was abrogated by neutralizing LGALS9 and could be rescued with recombinant LGALS9. Conclusion: We identified deranged developmental hierarchy characterized by co-expression of stemness programs in multiple malignant cell states and ineffectual commitment to either lymphoid or myeloid lineage in ETP T-ALL. Leukemic blasts demonstrate preexisting heterogeneity of diverse oncogenic states as evidenced by opposing PI3K and Notch activity, suggesting possible novel combination therapies. Notch inhibition abolishes the Notch high state without effecting the PI3K active state. Finally, we demonstrate a possible role for HAVCR2-LGALS9 interactions in causing CD8+ T-cell dysfunction in ETP T-ALL patients, which may provide a novel therapeutic strategy in this disease. Disclosures Silverman: Takeda: Consultancy; Servier: Consultancy, Research Funding. Lane:AbbVie: Research Funding; Stemline Therapeutics: Research Funding; N-of-One: Consultancy. DeAngelo:Glycomimetics: Research Funding; Amgen, Autolus, Celgene, Forty-seven, Incyte, Jazzs, Pfizer, Shire, Takeda: Consultancy; Blueprint: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Abbvie: Research Funding. Lohr:Celgene: Research Funding; T2 Biosystems: Honoraria.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 512-512 ◽  
Author(s):  
Ingrid G Winkler ◽  
Valerie Barbier ◽  
Kristen J Radford ◽  
Julie M Davies ◽  
Jean-Pierre Levesque ◽  
...  

Abstract T-cells are critical mediators of immune defense against pathogens and cancer. Adoptive T cell immunotherapy and T-cell engineering have promising clinical applications but T cell survival and exhaustion are current limitations. Central memory cells (TCM CD62L+ CCR7+) and their precursors, stem central memory T-cells (TSCM) possess the stem-like properties needed to reconstitute and prolong an effective immune response long-term. These cells have been shown to significantly improve therapeutic efficacy of adoptive T-cell therapy. The challenge remains to harvest good quality TCM-cells for these immunotherapy approaches. The bone marrow (BM) is the major reservoir of CD8+ TCM and their precursors. We have previously shown that E-selectin is expressed in the BM vasculature and drives activation and differentiation of hematopoietic stem cells during G-CSF induced mobilization to the blood. We find therapeutic blockade of E-selectin promotes HSC self-renewal and reconstitution in vivo. We now examine the impact of E-selectin blockade on CD8+ T cell mobilization from the bone marrow to the blood and hypothesize that E-selectin blockade may also dampen the activation/differentiation of this subset. First we administered a standard G-CSF regime (filgastim 250ug/kg/day for 3 days) to mice and then dosed some cohorts with GMI-1271 (40mg/kg BID) from 12 to 72 hours within this 3 day period. Administration of G-CSF alone results in a near complete disappearance of bone marrow resident CD8+ TCM cells, and their apparent migration (increase in numbers) to the blood, while CD8+ subsets in the lymph nodes and spleen were barely affected by G-CSF. Furthermore among T-cell subsets, CD8+ but not CD4+ TCM were specifically mobilized into the blood when GMI-1271 was co-administered for the last 12 to 24 hours of G-CSF. These findings are consistent with reports demonstrating the bone marrow to be a major reservoir for CD8+ but not CD4+ central memory T-cells. Administration of GMI-1271 caused a marked enhancement in mobilization into the blood of CD8+ TCM/SCM (CD62Lhi, CCR7+) cells over treatment with G-CSF alone (p<0.05). To determine the functional consequences of this skewed mobilization following GMI-1271 co-administration, 25 uL of mobilized blood was transplanted into irradiated congenic B6.SJL recipients together with 2x105 congenic BM cells to analyze long-term donor T-cell engraftment in the recipient mice. We found G-CSF mobilized donor blood did not contribute CD8+ TCM cells that can persist post-transplant (<0.5% at 20 weeks post-transplant). In contrast when donor mice were mobilized with G-CSF together with E-selectin blockade (GMI-1271), we found elevated levels of donor blood derived CD8+ T-cells demonstrating robust long-term CD8+ T-cell persistence / regeneration (5.3 ±3.2% of total recipient T-cells, p=0.04). This dramatic boost in donor CD8+ T-cell reconstitution in mobilized blood following GMI-1271 co-administration is likely to be due to the long-term persistence and in vivo amplification of CD8+ TCM cells from donor mobilized blood. Similar in vivo enhancing effects of GMI-1271 were also observed with other mobilizing agents such as combined CXCR4 and VLA-4 blockade and GM-CSF resulting in a significant 4.9-fold boost in donor CD8+ reconstitution with GMI-1271. Importantly, only 12 hours of E-selectin blockade was sufficient to achieve this boost in CD8+ TCM numbers in the blood following G-CSF. In a previous report we have shown that therapeutic blockade of E-selectin promotes HSC self-renewal in vivo. Thus, it is possible that E-selectin blockade boosts mobilization of CD8+ TCM/SCM with stem-like properties into the blood by loosening factors retaining CD8+ TCM/SCM in the bone marrow and/or blocking the E-selectin-mediated activation and differentiation of this T-cell subset. In summary, our studies identify E-selectin blockade as a novel target to improve harvesting of CD8+ TCM/SCM cells with stem-like properties. Blockade of this target with GMI-1271 significantly improves the in vivo reconstitution potential and regenerative properties of CD8+ T-cells from donor blood allowing a valuable source of desired T-cells for use in adoptive immunotherapy and T-cell engineering. Disclosures Winkler: GlycoMimetics Inc: Research Funding. Barbier:GlycoMimetics Inc: Research Funding. Davies:GlycoMimetics Inc: Research Funding. Smith:GlycoMimetics, Inc.: Employment. Fogler:GlycoMimetics, Inc.: Employment. Magnani:GlycoMimetics Inc: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
1997 ◽  
Vol 90 (5) ◽  
pp. 2103-2108 ◽  
Author(s):  
Mark K. Slifka ◽  
Jason K. Whitmire ◽  
Rafi Ahmed

Abstract Immunizing bone marrow donors prior to bone marrow transplant (BMT) has the potential for adoptively transferring specific immunity against opportunistic pathogens. Studies have shown that long-term antibody production occurs in the bone marrow and that specific humoral immunity may be transferred from donor to recipient following BMT. However, the magnitude and duration of T-cell memory in the bone marrow compartment has not been adequately investigated. In this study, virus-specific CD8+ T-cell responses in the bone marrow were compared with those observed in the spleen of mice acutely infected with lymphocytic choriomeningitis virus (LCMV). During the acute stages of infection, most CD8+ T cells in the spleen and bone marrow showed upregulated surface expression of the activation/memory marker, LFA-1 (LFA-1hi). After clearing LCMV infection, the antiviral immune response subsided to homeostatic levels and the ratio of CD8+/LFA-1hi to CD8+/LFA-1lo T cells in the spleen and bone marrow of LCMV immune mice returned to the value observed in naive mice. Virus-specific ex vivo effector cytotoxic T-lymphocyte (CTL) responses could be identified in both spleen and bone marrow compartments at 8 days postinfection. LCMV-specific CTL precursor (CTLp) frequencies peaked in the bone marrow at 8 days postinfection and averaged one in 200 to one in 650 CD8+ T cells, a frequency similar to that observed in the spleen. After clearing the acute infection, potent LCMV-specific CTL memory responses could be demonstrated in the bone marrow for at least 325 days postinfection, indicating long-term persistence of antiviral T cells at this site. Adoptive transfer of LCMV-immune bone marrow into severe combined immunodeficiency (SCID) mice provided protection against viral challenge, whereas SCID mice that received naive bone marrow became chronically infected upon challenge with LCMV. These results indicate that after acute viral infection, virus-specific memory T cells can be found in the bone marrow compartment and are maintained for an extended period, and when adoptively transferred into an immunodeficient host, they are capable of conferring protection against chronic viral infection.


Blood ◽  
2004 ◽  
Vol 103 (3) ◽  
pp. 988-994 ◽  
Author(s):  
Kimberly S. Schluns ◽  
Kimberly D. Klonowski ◽  
Leo Lefrançois

AbstractInterleukin 15 (IL-15) and the IL-15 receptor α (IL-15Rα) chain are both required for the basal proliferation of memory CD8 T cells, but which cell types are required to express IL-15 or IL-15Rα to mediate this proliferation is not known. Using bone marrow (BM) chimeras, we showed that virus-specific CD8 memory T-cell proliferation was driven by IL-15 produced by either BM-derived or parenchymal cells. Experiments using mixed BM chimeras showed that IL-15Rα expression by memory CD8 T cells was not required for their division. In addition, wild-type memory CD8 T cells did not divide after transfer into IL-15Rα-/- mice. Further analyses demonstrated that IL-15Rα+ BM-derived cells were crucial in driving memory CD8 T-cell division in the spleen while both parenchymal and BM-derived cells promoted memory cell division in the lung. Proliferation in response to soluble IL-15 in vivo required expression of IL-15Rα by opposing cells and IL-15Rβ by CD8 memory cells, indicating that IL-15 interacted directly with the T cells. These results indicate that transpresentation of IL-15 by IL-15Rα on BM-derived cells mediates the basal proliferation of memory CD8 T cells. (Blood. 2004;103:988-994)


eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Isaac J jensen ◽  
Xiang Li ◽  
Patrick W McGonagill ◽  
Qiang Shan ◽  
Micaela G Fosdick ◽  
...  

The global health burden due to sepsis and the associated cytokine storm is substantial. While early intervention has improved survival during the cytokine storm, those that survive can enter a state of chronic immunoparalysis defined by transient lymphopenia and functional deficits of surviving cells. Memory CD8 T cells provide rapid cytolysis and cytokine production following re-encounter with their cognate antigen to promote long-term immunity, and CD8 T cell impairment due to sepsis can pre-dispose individuals to re-infection. While the acute influence of sepsis on memory CD8 T cells has been characterized, if and to what extent pre-existing memory CD8 T cells recover remains unknown. Here, we observed that central memory CD8 T cells (TCM) from septic patients proliferate more than those from healthy individuals. Utilizing LCMV immune mice and a CLP model to induce sepsis, we demonstrated that TCM proliferation is associated with numerical recovery of pathogen-specific memory CD8 T cells following sepsis-induced lymphopenia. This increased proliferation leads to changes in composition of memory CD8 T cell compartment and altered tissue localization. Further, memory CD8 T cells from sepsis survivors have an altered transcriptional profile and chromatin accessibility indicating long-lasting T cell intrinsic changes. The sepsis-induced changes in the composition of the memory CD8 T cell pool and transcriptional landscape culminated in altered T cell function and reduced capacity to control L. monocytogenes infection. Thus, sepsis leads to long-term alterations in memory CD8 T cell phenotype, protective function and localization potentially changing host capacity to respond to re-infection.


2019 ◽  
Author(s):  
Veronica Davé ◽  
E. Fabian Cardozo-Ojeda ◽  
Florian Mair ◽  
Jami Erickson ◽  
Amanda S. Woodward-Davis ◽  
...  

AbstractTissue-resident memory CD8 T cells (CD8 TRM) are critical for maintaining barrier immunity. CD8 TRM have been mainly studied in the skin and gut with recent studies suggesting that the signals that control tissue-residence and phenotype are highly tissue-dependent. We examined the T cell compartment in healthy human cervicovaginal tissue (CVT) and found that most CD8 T cells were granzyme B+ and TCF-1-. To address if this phenotype is driven by CVT tissue-residence, we used a mouse model to control for environmental factors. Using localized and systemic infection models, we found that CD8 TRM in the mouse CVT gradually acquired a granzyme B+, TCF-1- phenotype as seen in human CVT. In contrast to CD8 TRM in the gut, these CD8 TRM were not stably maintained regardless of the initial infection route, which led to reductions in local immunity. Our data show that residence in the CVT is sufficient to progressively shape the size and function of its CD8 TRM compartment.SummaryThe tissue-resident memory (TRM) CD8 T cell compartment in human and mouse cervicovaginal tissue (CVT) is remarkably similar. The CVT TRM compartment is maintained autonomously and does not reach phenoypical or numerical equilibrium. The numerical decline leads to impaired viral control in a secondary challenge.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1868-1868 ◽  
Author(s):  
Billy Michael Chelliah Jebaraj ◽  
Annika Scheffold ◽  
Eugen Tausch ◽  
Judith A. Fox ◽  
Pietro Taverna ◽  
...  

Abstract B cell receptor signaling (BCR) in chronic lymphocytic leukemia (CLL) drives tumor cell proliferation and survival. Inhibition of Bruton's tyrosine kinase (BTK), a key enzyme in the BCR pathway, has proved to be efficacious even in poor-risk and chemo-refractory patients. However resistance to the BTK inhibitor ibrutinib has been shown to emerge in a subset of CLL patients. Of importance, the C481S BTK mutation conferred resistance by preventing the covalent binding of ibrutinib to its target cysteine 481 in BTK. Vecabrutinib (formerly known as SNS-062, a succinate salt) is a novel, highly potent, next generation noncovalent BTK inhibitor which demonstrated biochemical and cellular activity against C481S BTK mutant in vitro. However, the efficacy of vecabrutinib and its impact on the T-cell microenvironment has not been studied in in vivo preclinical CLL models. In the present study, the efficacy of vecabrutinib was investigated using the Eµ-TCL1 adoptive transfer model. Mice were randomized to treatment with either 40mg/kg vecabrutinib succinate, twice daily by oral gavage (n=6) or vehicle control (n=6). The mice were sacrificed after 2 weeks of treatment and changes in tumor burden as well as alterations in T-cell microenvironment were analysed in detail. Treatment with vecabrutinib decreased tumor burden as observed by a significant decrease in WBC count (36.5 vs. 17.1 giga/L; P=0.002), spleen weight (median 0.56g vs. 0.31g; P=0.005) and liver weight (median 1.5g vs. 1.2g; P=0.005) compared to vehicle treatment. Correspondingly, the CD5+ CD19+ tumor cells were significantly decreased in blood (P=0.002) and spleen (P=0.002) while no significant difference was observed in bone marrow (P=0.818) upon treatment with vecabrutinib. Since BTK inhibition is known to reshape the tumor microenvironment, we studied the impact of vecabrutinib specifically on T-cell subsets. Firstly, no difference in the proportions of CD4 or CD8 expressing T-cells was observed in mice treated with vehicle or vecabrutinib. However, of interest, the percentage of CD4+ CD25+ FoxP3+ regulatory T cells (Tregs) were significantly decreased upon treatment with vecabrutinib in peripheral blood (P=0.026) and spleen (P=0.009). The decrease in Tregs was due to reduced proliferation of these cells upon exposure to the drug as measured by Ki-67 staining. Also, the Tregs expressing the maturation and activation markers such as CD103 and GITR were significantly decreased in blood and spleen upon drug treatment. Further, we analysed the changes in CD8 T-cell subsets following treatment with vecabrutinib. Treatment with the drug resulted in expansion of the CD127+ CD44- naïve CD8 T-cells in blood, bone marrow and spleen (all P values 0.002) while the CD127+ CD44+ memory CD8 T-cells were significantly decreased in bone marrow and spleen (all P values 0.009). Also, the CD127low CD44int-hi effector CD8 T-cells were decreased in blood (P=0.004), bone marrow (P=0.004) and spleen (P=0.002) upon vecabrutinib treatment. Therefore, vecabrutinib treatment did not alter the percentage of CD4+ and CD8+ T cells in mice however, significant changes in the subset composition of the CD4 and CD8 T cells were observed. Lastly, to analyse the impact of vecabrutinib on survival, a cohort of mice (n=12) were transplanted with 5 million splenic tumor cells isolated from Eµ-TCL1 transgenic mice. After allowing for engraftment, the mice were randomized to treatment with the drug (n=6) or vehicle (n=6). Of note, the mice treated with the drug showed a significant increase in survival (median 35 days from transplant; P<0.001) compared to treatment with vehicle (median 28 days). In summary, vecabrutinib was efficacious in vivo in a preclinical CLL adoptive transfer model, decreasing tumor burden in different organs and significantly improving survival. Treatment with the drug altered the T-cell architecture in vivo. Of interest, the immunosuppressive Tregs, which protect the tumor from immune surveillance were decreased in various tissue compartments; however, a decrease in the effector CD8 T cells might impact anti-tumor immunity if there is a consistent effect upon drug treatment. Vecabrutinib antitumor activity and effects on T-cell populations in vivo in this preclinical CLL model are intriguing, merits further investigation and supports the ongoing phase 1b/2 study in patients with previously treated B-lymphoid malignancies (NCT03037645). Disclosures Tausch: AbbVie: Consultancy, Other: Travel grants; Celgene: Consultancy, Other: Travel grants; Gilead: Consultancy, Other: Travel grants. Fox:Sunesis Pharmaceuticals: Employment; Amphivena Therapeutics: Employment. Taverna:Sunesis Pharmaceuticals: Employment. Stilgenbauer:Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Genentech: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Boehringer-Ingelheim: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Hoffmann La-Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Genzyme: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmcyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Mundipharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4370-4370
Author(s):  
Sulima Geerman ◽  
Fernanda M Pascutti ◽  
Sudeep Bhushal ◽  
Martijn A. Nolte

Abstract The bone marrow (BM) has an important function as primary lymphoid organ through the process of hematopoiesis. This process is sustained by hematopoietic stem cells (HSCs) and their life-long production of new blood cells, which is made possible by their unique ability to self-renew. Next to this, BM also functions as a secondary lymphoid organ, as it can mediate primary T cell responses against invading pathogens. We and others have shown that activated T cells can influence the hematopoietic process through the production of pro-inflammatory cytokines. This indicates that adaptive immune responses and hematopoiesis are intertwined in the BM, though most of the cellular and molecular interactions that occur during this crosstalk are yet unknown. Based on previous observations that T cell deficient mice have altered hematopoiesis and that depletion of T cells from allogeneic BM grafts compromises HSC engraftment, we questioned to what extent BM T cells can directly affect the function of HSCs. To test this, we sorted and co-cultured murine BM T cells with HSCs (Lin-Sca-1+c-Kit+CD48-CD150+). We found that particularly BM CD8+ central memory (CD44+CD62L+) T cells (Tcm) enhance the capacity of HSCs to self-renew. Furthermore, we found that TCR-transgenic mice, which do not have memory T cells, have lower numbers of HSCs, which could subsequently be increased by transferring BM CD8+ Tcm. Remarkably, an increase in HSC numbers was also observed when HSCs were cultured with only supernatant derived from BM CD8+ Tcm. Moreover, HSCs cultured with supernatant from BM CD8+ Tcm and later transplanted in myeloablated hosts displayed a strongly enhanced ability to restore hematopoiesis. Importantly, the strong impact of BM T cells on HSCs was not only apparent in the steady state situation, but also following a viral infection with either acute or chronic lymphocytic choriomeningitis virus (LCMV). We could establish that both acute and chronic LCMV-specific CD8+ T cells or supernatant from these cells could increase the HSC self-renewal capacity. In conclusion, our findings demonstrate that BM memory CD8+ T cells can positively influence the function of HSC through soluble mediators. We postulate that this process is particularly relevant after immune activation, in order to protect and/or restore the HSC pool and the subsequent hematopoietic recovery. We are currently using a proteomics approach to identify these soluble mediator produced by CD8+ T cells. Disclosures No relevant conflicts of interest to declare.


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