CD8+ T Cells Mediate Antibody-Independent Platelet Clearance Following Transfusion

Abstract Background: Alloimmunization to major histocompatibility complex (MHC) antigens is the leading immunological barrier to transplantation and platelet transfusion therapy. In the context of platelet transfusion medicine, alloimmunization to MHC antigens can substantially diminish the therapeutic efficacy of subsequent blood transfusions. Presently, MHC alloantibodies are recognized as the primary mediators of immune-mediated platelet clearance. However, individuals previously exposed to MHC alloantigens can display significant platelet clearance in the absence of detectable anti-platelet antibodies. Given the ability of cellular immunity to mediate rejection of solid organ allografts across MHC differences, we hypothesized that cellular immunity likewise facilitates the clearance of platelets in MHC alloimmunized recipients. Methods: FVB (H-2Kq) MHC-immunized or non-immunized C57BL/6 (H-2Kb) recipients were transfused with filter leukoreduced platelet rich plasma (PRP) isolated from C57BL/6 donors expressing green fluorescent protein (GFP) under a H-2Kb promoter (B6 GFP) or PRP obtained from a FVB X B6 GFP F1 cross, which generates GFP+ H-2Kq+ platelets. Following transfusion, mice were bled at 10 minutes, 1 hour, 2 hours or 24 hours to calculate the percentage of GFP+ transfused platelets remaining using flow cytometric analysis. To test the hypothesis that platelet clearance can occur in an antibody-independent process, FVB H-2Kq MHC-immunized or non-immunized μMT recipients were similarly transfused with B6 GFP or FVB X B6 GFP PRP. CD8+ T cells in immunized μMT recipients were depleted by i.p. injection of anti-CD8 (clone 2.43) antibody for 3 consecutive days prior to transfusion. NK cells were similarly depleted by injection of anti-NK1.1 (clone PK-136) antibody, 1 day prior to transfusion. CD4, CD8 T cell and NK cell depletion was evaluated in the peripheral blood prior to platelet transfusion, and compared to non-treated and isotype control treated recipients. Results: While GFP+ platelets were readily detected following transfusion into non-immunized or MHC matched recipients, transfusion of FVB-B6 platelets into H-2Kq MHC-immunized C57BL/6 recipients resulted in rapid clearance within the first hour following transfusion. In contrast, though little platelet clearance was detected in H-2Kq MHC-immunized μMT recipients within an hour following transfusion, very few transfused platelets were observed after 24 hours. Moreover, despite platelet clearance, anti-MHC antibodies were not detectable in μMT recipients. To determine the cellular component responsible for clearance in alloimmunized μMT recipients, CD8+ T cells or NK cells were depleted prior to transfusion. NK cell depletion failed to impact platelet clearance in alloimmunized μMT recipients; however, depletion of CD8+ T cells prior to platelet transfusion abrogated platelet clearance in immunized μMT recipients. Conclusion: Immunized recipients rapidly clear platelets in an alloantigen specific fashion following platelet transfusion in a murine model. Though platelet clearance occurred at a faster rate in intact immunized C57BL/6 recipients, B cell deficient MHC-immunized μMT recipients possessed the capacity to induce significant clearance at later time points. Evaluation of the cellular populations responsible for antibody-independent clearance in μMT recipients strongly suggest that CD8+ T cells play a key role in antibody-independent immune-mediated platelet clearance. These results suggest that, in addition to antibodies, CD8+ T cells can play a role in the development of platelet refractoriness and may contribute to platelet non-responsiveness in patients with little to no detectable anti-platelet alloantibodies. Disclosures No relevant conflicts of interest to declare.

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Targeting CD137 to enhance the antitumor efficacy of cetuximab by stimulation of innate and adaptive immunity.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.15_suppl.3015 ◽

2013 ◽

Vol 31 (15_suppl) ◽

pp. 3015-3015 ◽

Cited By ~ 3

Author(s):

Holbrook Edwin Kohrt ◽

Roch Houot ◽

Kipp Weiskopf ◽

Matthew Goldstein ◽

Peder Lund ◽

...

Keyword(s):

Clinical Trial ◽

T Cells ◽

T Cell ◽

Nk Cells ◽

Adaptive Immunity ◽

Cd8 T Cells ◽

Nk Cell ◽

Cell Depletion ◽

Innate And Adaptive Immunity ◽

Cetuximab Therapy

3015 Background: Cetuximab therapy results in beneficial, yet limited, clinical improvement for patients with KRAS wildtype (WT) colorectal (CRC) and head and neck (HN) cancer. The efficacy of cetuximab, an IgG1 monoclonal antibody against EGFR, is due in part to antibody-dependent cell-mediated cytotoxicity (ADCC) by natural killer (NK) cells. CD137 is a costimulatory molecule expressed following activation on NK and memory, antigen-specific, CD8 T cells. Methods: We investigated the hypothesis that the combination of cetuximab with anti-CD137 mAb will enhance innate and adaptive immunity, thereby improving cetuximab’s anti-tumor efficacy in preclinical models and a prospective trial, NCT01114256. Results: NK cells increased their expression of CD137 by a factor of 30-40 when exposed to cetuximab-coated, EGFR-expressing HN and CRC cell lines. An agonistic anti-CD137 mAb enhanced NK cell degranulation and cytotoxicity 2-fold (~45 to 90% tumor lysis assayed by chromium release). The combination of cetuximab and anti-CD137 mAbs was synergistic in a syngeneic, human-EGFR-transfected murine tumor leading to complete tumor resolution and prolonged survival. NK cell depletion, significantly, and CD8 T cell depletion, partly, abrogated the anti-tumor efficacy of this combination. A series of HN and both KRAS WT and mutant CRC xenotransplant models demonstrated synergy with cetuximab and anti-CD137 mAbs. In our clinical trial, 54 patients with HN cancer receiving cetuximab therapy, circulating and intratumoral NK cells upregulated CD137 with amplitude influenced by duration post-cetuximab and host FcyRIIIa polymorphism. Interestingly, in 10 HLA-A2+ patients, following cetuximab, an increase in EGFR-specific, CD137-expressing, CD8 T cells directly correlated with the percent increase in CD137-expressing NK cells. Conclusions: Our results demonstrate the synergy of combining an agonistic mAb, anti-CD137, augmenting ADCC and T cell memory following a tumor-targeting mAb, cetuximab, in HN and KRAS mutant and WT CRC cancer. These results support a novel, sequential antibody approach by targeting first the tumor and then the host innate and adaptive immune system. Clinical trial information: NCT01114256.

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KS01.4.A NK cells as key orchestrators in mediating the anti-tumour response to immune checkpoint blockade in melanoma brain metastases

Neuro-Oncology ◽

10.1093/neuonc/noab180.008 ◽

2021 ◽

Vol 23 (Supplement_2) ◽

pp. ii3-ii3

Author(s):

C M Fife ◽

J Williams ◽

R Brownlie ◽

T Andreou ◽

A Sunderland ◽

...

Keyword(s):

Gene Expression ◽

T Cells ◽

Brain Metastases ◽

Nk Cells ◽

Cd8 T Cells ◽

Immune Checkpoint ◽

Nk Cell ◽

Immune Checkpoint Blockade ◽

Cell Depletion

Abstract BACKGROUND Brain metastases (BrM) are an unmet clinical need with poor prognosis. 60% of melanoma patients develop BrM. BrM are strongly understudied due to frequent exclusion from clinical trials, and hence treatment options commonly lag behind. Antibodies targeting the immune-inhibitory receptors cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1) have demonstrated efficacy against melanoma BrM. Despite this, therapeutic responses are highly variable, and it is unknown why therapy fails in a high proportion of patients. Improved therapeutic strategies require a thorough understanding of potentially exploitable mechanisms of therapeutic efficacy. Our data previously implicated different immune cells, foremost CD8+ T cells, but also NK cells, in the intracranial efficacy and enhanced survival benefit of immune checkpoint blockade (ICB). Our aim here is to investigate the role of NK cells in mediating the response to ICB in melanoma BrM. MATERIAL AND METHODS To study the role of NK cells in the response to ICB in melanoma BrM, a tumour transplantation model of B16 melanoma with simultaneous extracranial (i.e., flank) and brain tumours in C57BL/6 mice was utilised. NK cells were depleted through administration of anti-asialo-GM1 NK cell-depleting antibodies. Confirmation of NK cell depletion and quantification of intratumoral immune cell populations was performed using flow cytometry. Intratumoral gene expression of key chemokines and immune mediator genes was assessed using RT-qPCR and mRNA-seq. RESULTS Highly variable response to ICB with respect to intratumoral accumulation of CD8+ T cells allowed separation of mice into responders and non-responders and revealed genes and pathways associated with response to ICB. NK cell depletion reversed the ICB-mediated increase in the accumulation of CD8+ T cells and significantly reduced the expression of genes associated with response in intracranial and extracranial tumours. The ICB-mediated significant increase in gene expression of various chemokines (i.e., Cxcl9/10) and immune mediators (i.e., Ifng, Prf1 and Gzmb) was significantly abrogated upon NK cell depletion. CONCLUSION NK cells play a critical role in the underlying mechanisms of ICB efficacy through their modulation of the tumour microenvironment and enhancement of CD8+ T cell accumulation in intracranial tumours. Targeting of NK cells may allow potentiation of ICB therapy in the brain, as well as at extracranial sites.

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DNAM-1 promotes activation of cytotoxic lymphocytes by nonprofessional antigen-presenting cells and tumors

Journal of Experimental Medicine ◽

10.1084/jem.20081752 ◽

2008 ◽

Vol 205 (13) ◽

pp. 2965-2973 ◽

Cited By ~ 195

Author(s):

Susan Gilfillan ◽

Christopher J. Chan ◽

Marina Cella ◽

Nicole M. Haynes ◽

Aaron S. Rapaport ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Nk Cells ◽

Adhesion Molecules ◽

Cd8 T Cells ◽

Nk Cell ◽

Cd8 T Cell ◽

Antigen Presenting

Natural killer (NK) cells and CD8 T cells require adhesion molecules for migration, activation, expansion, differentiation, and effector functions. DNAX accessory molecule 1 (DNAM-1), an adhesion molecule belonging to the immunoglobulin superfamily, promotes many of these functions in vitro. However, because NK cells and CD8 T cells express multiple adhesion molecules, it is unclear whether DNAM-1 has a unique function or is effectively redundant in vivo. To address this question, we generated mice lacking DNAM-1 and evaluated DNAM-1–deficient CD8 T cell and NK cell function in vitro and in vivo. Our results demonstrate that CD8 T cells require DNAM-1 for co-stimulation when recognizing antigen presented by nonprofessional antigen-presenting cells; in contrast, DNAM-1 is dispensable when dendritic cells present the antigen. Similarly, NK cells require DNAM-1 for the elimination of tumor cells that are comparatively resistant to NK cell–mediated cytotoxicity caused by the paucity of other NK cell–activating ligands. We conclude that DNAM-1 serves to extend the range of target cells that can activate CD8 T cell and NK cells and, hence, may be essential for immunosurveillance against tumors and/or viruses that evade recognition by other activating or accessory molecules.

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Transient and persistent effects of IL-15 on lymphocyte homeostasis in nonhuman primates

Blood ◽

10.1182/blood-2010-03-275438 ◽

2010 ◽

Vol 116 (17) ◽

pp. 3238-3248 ◽

Cited By ~ 72

Author(s):

Enrico Lugli ◽

Carolyn K. Goldman ◽

Liyanage P. Perera ◽

Jeremy Smedley ◽

Rhonda Pung ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Nk Cells ◽

T Cell Activation ◽

Cd8 T Cells ◽

Cell Activation ◽

Nk Cell ◽

The Body ◽

Effector Memory ◽

Memory Cd8 T Cells

Abstract Interleukin-15 (IL-15) is a cytokine with potential therapeutic application in individuals with cancer or immunodeficiency to promote natural killer (NK)– and T-cell activation and proliferation or in vaccination protocols to generate long-lived memory T cells. Here we report that 10-50 μg/kg IL-15 administered intravenously daily for 12 days to rhesus macaques has both short- and long-lasting effects on T-cell homeostasis. Peripheral blood lymphopenia preceded a dramatic expansion of NK cells and memory CD8 T cells in the circulation, particularly a 4-fold expansion of central memory CD8 T cells and a 6-fold expansion of effector memory CD8 T cells. This expansion is a consequence of their activation in multiple tissues. A concomitant inverted CD4/CD8 T-cell ratio was observed throughout the body at day 13, a result of preferential CD8 expansion. Expanded T- and NK-cell populations declined in the blood soon after IL-15 was stopped, suggesting migration to extralymphoid sites. By day 48, homeostasis appears restored throughout the body, with the exception of the maintenance of an inverted CD4/CD8 ratio in lymph nodes. Thus, IL-15 generates a dramatic expansion of short-lived memory CD8 T cells and NK cells in immunocompetent macaques and has long-term effects on the balance of CD4+ and CD8+ T cells.

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Natural Killer Cell Immune Reconstitution Predicts Outcomes for Patients with Chronic Lymphocytic Leukemia Undergoing Allogeneic Stem Cell Transplantation

Blood ◽

10.1182/blood.v112.11.3300.3300 ◽

2008 ◽

Vol 112 (11) ◽

pp. 3300-3300

Author(s):

Don Benson ◽

Leslie Andritsos ◽

Mehdi Hamadani ◽

Thomas Lin ◽

Joseph Flynn ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Nk Cells ◽

Cd8 T Cells ◽

Immune Reconstitution ◽

Nk Cell ◽

Disease Status ◽

Lymphocytic Leukemia ◽

T Cell Subsets ◽

Cell Recovery

Abstract Introduction: Chronic lymphocytic leukemia (CLL), the most common form of leukemia in the Western hemisphere, is associated with severe innate, adaptive and humoral immune dysregulation. CLL remains essentially incurable, with the potential exception of allogeneic stem cell transplantation (ASCT). Natural killer (NK) cells are CD56(+), CD3(−) large granular lymphocytes that comprise a key cellular subset of the innate immune system. Preliminary in vitro data suggest an NK cell versus CLL effect exists, similar to that observed in acute myeloid leukemia (AML) and other blood cancers. Novel immune therapies for CLL (e.g., rituximab, alemtuzumab) likely exert anti-tumor effect, in part, through NK cells, in fact. Although NK cells contribute to the graft-versus-tumor effect following ASCT for other blood cancers, little is known regarding the potential role NK cells may play in the clinical allogeneic transplant setting for CLL. Herein, we provide, to our knowledge, the first report regarding NK cell immune reconstitution following ASCT for CLL. Methods: 27 CLL patients underwent reduced intensity conditioning (RIC) with ASCT. Median age was 52 years (43–69), median number of prior therapies was 3 (2–11). 55% had chemotherapy-refractory disease, and 55% had “high-risk” cytogenetics by FISH (deletion 17p or 11q22-23 abnormality). 14 patients had sibling donors, 15 had volunteerunrelated donors. Conditioning regimens included Fludarabine/TBI/Alemtuzumab (n=8), Fludarabine/Busulfan with (n=9) or without ATG (n=6), and Fludarabine/Cyclophosphamide (n=4). GVHD prophylaxis consisted of tacrolimus/MMF (n=8) or tacrolimus/methotrexate (n=19). Patients underwent bone marrow assessment prior to day +75 following ASCT. Marrow was studied for engraftment, donor chimerism, and disease status as well as lymphoid immune reconstitution by percentage of total lymphocytes and absolute lymphocyte counts by multi-color flow cytometry. Results: NK cell immune reconstitution was predicted by disease status at transplantation. Patients in complete or partial remission at the time of ASCT had more robust NK cell recovery (mean = 45% of total lymphocytes +/− SEM 5%) as compared to patients entering transplant with refractory disease (16% +/− 1, p < 0.01). No differences were observed in CD4(+) or CD8(+) T cells and no lymphocyte subset recovery was associated with CD34(+) or CD3(+) cell dosage. Achieving complete donor chimerism by day +60 was associated with robust NK cell recovery (55% +/− 1 versus 7% +/−1, p = 0.02), recovery of CD4 and CD8 T cells was not associated with chimerism status, however. Patients who went onto exhibit a complete response to ASCT had greater early NK cell reconstitution (31% +/− 3) as compared to those who had no response (8% +/− 1, p = 0.01). No differences in T cell subsets were associated with response. Patients who ultimately achieved complete remission following transplant had a lower CLL:NK cell ratio in marrow (0.35 +/− 0.07) than those who did not (8.1 +/− 1, p = 0.01). However, differences in CLL:CD4(+) and CLL:CD8(+) T cells were not predictive of response. Trends to improvement in progression free survival and overall survival were observed for patients with NK cell reconstitution above the median for the group as compared to those below; no such trends were observed regarding T cell subsets. Greater NK cell reconstitution trended towards ultimate eradication of minimal residual disease following ASCT, but no such trends were observed for T cell subsets. Conclusions: Early NK cell recovery predicts survival following autologous and allogeneic SCT in a number of hematologic malignancies; however, little is known regarding this phenomenon in CLL. To our knowledge, these are the first findings to implicate a potentially important therapeutic role for early NK cell compartment recovery in CLL following ASCT. Further research into restoring and augmenting NK cell function following RIC/ASCT for CLL is warranted.

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Long Lasting Alteration of Natural Killer Cells Post-Chemotherapy in Elderly Patients with Acute Myeloid Leukemia (AML).

Blood ◽

10.1182/blood.v114.22.1653.1653 ◽

2009 ◽

Vol 114 (22) ◽

pp. 1653-1653

Author(s):

Daniel Olive ◽

Nicolas Anfossi ◽

Pascale Andre ◽

Jerome Rey ◽

Florence Orlanducci ◽

...

Keyword(s):

T Cells ◽

Immune System ◽

Elderly Patients ◽

Nk Cells ◽

Natural Killer ◽

Cd8 T Cells ◽

Nk Cell ◽

Time Points ◽

Early Stages ◽

Cell Counts

Abstract Abstract 1653 Poster Board I-679 Background The immune system is involved in AML control and Natural Killer (NK) cells are among the most promising effectors. The therapeutic potential of NK cells has been revealed by the Killer Immunoglobulin Receptor (KIR) mismatch allogeneic transplant model where the anti-leukemic effect of the graft, is due to unleashed NK cells towards AML blasts, as suggested by enhanced in vitro lytic activity of KIR-HLA mismatched donor NK cells against recipient blasts (Miller et al. 2005; Ruggeri et al. 2002). Receptors involved in the function of NK cells against AML blasts have been identified (Pende et al., 2005). Some of these receptors are altered in AML patients at diagnosis and might be involved in the immune escape of AML blasts (Costello et al., 2002). However, the status of NK cells during early stages of patient's chemotherapy (CT) treatment is unknown. The present study monitored status of NK cells during early stages following patient's remission after CT that may be critical for their long lasting clinical response, and results might provide new targets for immunotherapy. Methods We enrolled 20 elderly patients (60 to 80 years old) with non promyelocytic AML in first CR following induction and pre-consolidation CT with normal renal and hepatic functions. Patient peripheral NK, gd T and CD8 T cells were analyzed before consolidation CT and every other week after treatment for 8 weeks. 6-colors flow cytometry was performed to investigate the expression of MHC receptors (CD158a, b, e, i, CD85j and NKG2A), activating receptors (NKp30, NKp46, NKG2D, CD16, DNAM-1, 2B4) as well as their differentiation status (perforin and granzyme expression). Their function, as determined by cytotoxicity (51Cr release and CD107 expression) and cytokine production (intracellular staining of IFN-g), was analyzed using purified NK cells stimulated by K562, or in redirected assays using NKp30, NKp46 and CD16 mAbs. Results NK cell counts were depressed away from the induction and pre-consolidation CT as compared to NK cell counts of age-matched controls (ctl) (95±107 NK/μL vs 229±91 NK/μL respectively); they were further depressed during the first 2 weeks post-consolidation CT (55±57 NK/μL), but were back to pre-consolidation CT level at 4 weeks (105±102 NK/μL). In contrast, CD8 T cells and gd T cells counts were normal even at early times post-CT. Expression of 2B4 was depressed at all time points. In contrast, NKp30 expression was lower at diagnosis and close to ctl level post-consolidation CT (p=0.0003) and NKp46 expression increased after CT (p<0.0001). Sizes of NK cell subsets expressing CD158a or CD158b in patients post-induction and consolidation CT were smaller than those of ctl (% CD158a+: p=0.003; % CD158b+: p=0.014). In contrast the NKG2A or CD85j positive NK cell subsets were either unchanged or slightly increased respectively at all time points (p=0.0015 for CD85j+). Moreover, sizes of perforin or granzyme positive NK cell subsets were increased in treated AML patients (% Granzyme+: p= 0.0125 and % Perforin+: p=0.0268). In addition, we observed an important heterogeneity in the expression of the surface receptors among patients that is currently analyzed with respect to the duration of the CR. Finally, NK cell cytoxicity was comparable at all time points to the one of age-matched ctl. In contrast, IFN-g secretion was decreased, at all time points, against K562 or in redirected assays using CD16 mAb and almost abolished using redirected assay with NKp30 mAb. Conclusions This study demonstrates that in elderly AML patients in CR after CT (1) several alterations are detected at all time points, (2) NK cell number is lower and (3) IFN-g secretion is impaired. However NK cytotoxic function is comparable to age-matched controls. The likely basis of the complex pattern of modifications might rely on an interplay between the direct and indirect effects of chemotherapy, activation of immune system, NK cell differentiation and its interaction with AML blasts. Altogether this study indicates that new immunotherapeutic approaches might be used to increase NK cell numbers and functions (cytotoxicity and IFN-g secretion) at early times post-CT in elderly patients with AML. Disclosures Romagne: Innate Pharma: Employment.

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Influence of Lenalidomide Treatment on Immune Effector Cells From High-Risk Smoldering Multiple Myeloma (SMM) Patients,

Blood ◽

10.1182/blood.v118.21.3944.3944 ◽

2011 ◽

Vol 118 (21) ◽

pp. 3944-3944

Author(s):

Bruno Paiva ◽

Maria Victoria Mateos ◽

Lucía López-Corral ◽

María-Belén Vidriales ◽

Miguel T. Hernandez ◽

...

Keyword(s):

T Cells ◽

High Risk ◽

Nk Cells ◽

Cd8 T Cells ◽

Nk Cell ◽

Γδ T Cells ◽

Activation Markers ◽

Hla Dr ◽

Activation Profile ◽

Immunomodulatory Properties

Abstract Abstract 3944 Lenalidomide is an immunomodulatory agent that enhances T and NK cell activation, being this consideration as a major player in its anti-myeloma effect. However, in MM lenalidomide is usually combined with the immunosuppressant dexamethasone, which has raised questions regarding a potential abrogation of this immunomodulatory effect. In fact, this may be a dilemma upon treating early stage MM patients with lenalidomide +/− dexamethasone. Moreover, our current knowledge of the immune system in SMM is limited. Herein we evaluated by multiparameter flow cytometry (MFC) immunophenotyping peripheral blood (PB) T and NK cells from high-risk SMM patients (N=33), treated according to the QUIREDEX trial (NCT 00480363): an induction phase of 9 four-week cycles of LenDex followed by maintenance with lenalidomide until disease progression. To evaluate the immune status of T and NK cells of SMM patients, we compared them at baseline vs healthy adults (HA) aged over 60 years (N=10). To assess the effect of LenDex on T and NK cells of SMM patients, we compared baseline samples vs those studied after 3 and 9 cycles of LenDex. To address the question whether dexamethasone antagonizes the immunomodulatory properties of lenalidomide, we compared in 11 of the 33 patients, the PB T and NK cells at the end of induction (9th cycle of LenDex) vs during maintenance (lenalidomide alone and at least 3 months after dexamethasone discontinuation). The percentage of PB T cells in high-risk SMM patients at baseline was increased when compared to HA (23% vs 17%; P=.02), mainly due to expansion of CD8 T cells (P=.03). Of note, γδ T cells were also increased in SMM (0.8% vs 0.3%; P=.003). In turn, no differences (P>.05) were noted for both the CD56dim and CD56bright NK cell compartments. However, when a more detailed immunophenotypic characterization was carried out, CD4 and/or CD8 T cells from SMM patients showed decreased expression of activation markers (CD25, P≤.04; CD54, P<.001 and CD154, P=.002), as well as decreased production of the Th1 related cytokines (IFNγ, P=.03; TNFα, P≤.003; and IL-2, P=.02). We then investigated the effect of LenDex treatment. After 3 and 9 cycles of LenDex both CD4 and/or CD8 T cells showed up-regulation of Th1related chemokines (CCR5; p<.001) and cytokine production (IFNγ, P=.03; TNFα, P=.03 and IL-2, P=.02), as well as increased expression of activation markers (CD69, P≤.005; CD25, P<.001; CD28, P≤.04; CD54, P<.001 and HLA-DR, P<.001). Similarly, CD56dim and CD56bright NK cells showed up-regulation of HLA-DR (P<.001), the antibody-dependent cell-mediated cytotoxicity associated receptor CD16 (p≤.005), and the adhesion molecules CD11a (p≤.001) and CD11b (p≤.005). Concerning cell cycle analysis, the percentage of cells in S-phase was significantly increased from baseline vs. 3 vs. 9 cycles of LenDex for T CD4 (0.04% vs 0.13% vs 0.13%; p<.001), CD8 (0.05% vs 0.13% vs 0.18%; p<.001) and NK cells (0.07% vs 0.16% vs 0.15%; p<.001). Interestingly, an unsupervised cluster analysis of the overall immunophenotypic expression profile obtained after 9 cycles of LenDex was able to discriminate two groups of patients with different activation profiles particularly on T CD8 cells, with differences (P<.05) in both their percentage in PB and expression of activation, Th1 and maturation markers. Patients displaying a higher activation profile showed a trend towards increased depth of response after 9 cycles of LenDex (sCR+CR: 31% vs 15%; p=.229), as well as time-to progression (TTP) to symptomatic MM (TTP at 2-years: 100% vs 79%; P=.177). Finally, we explored whether the immunomodulatory properties of lenalidomide could be increased when dexamethasone was removed for the maintenance phase. Regarding T and NK cell distribution, only an increase in the percentage of CD4 T cells was found (9% vs. 12%, P=.04), whereas no differences (P>.05) were noted regarding the immunophenotypic expression profile of T and NK cells studied. In summary, we show that in high-risk SMM patients at baseline CD8 and γδ T cells are increased but overall T cells show an impaired activation profile. Treatment with LenDex induces an activation and proliferation of T and NK cells which may contribute to disease control. Finally, our results do not show an inhibition of the immunomodulatory effects of lenalidomide by the concomitant use of dexamethasone. Disclosures: Paiva: Celgene: Honoraria; Janssen: Honoraria. Off Label Use: lenalidomide is not approved for smoldering myeloma. Mateos:Janssen: Honoraria; Celgene: Honoraria. Rosiñol:Janssen: Honoraria; Celgene: Honoraria. Lahuerta:Janssen: Honoraria; Celgene: Honoraria. Blade:Janssen: Honoraria; Celgene: Honoraria. San Miguel:Janssen-Cilag: Honoraria; Celgene: Honoraria.

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The tumor suppressor TSLC1/NECL-2 triggers NK-cell and CD8+ T-cell responses through the cell-surface receptor CRTAM

Blood ◽

10.1182/blood-2005-02-0817 ◽

2005 ◽

Vol 106 (3) ◽

pp. 779-786 ◽

Cited By ~ 114

Author(s):

Kent S. Boles ◽

Winfried Barchet ◽

Tom Diacovo ◽

Marina Cella ◽

Marco Colonna

Keyword(s):

T Cells ◽

T Cell ◽

Tumor Suppressor ◽

Cell Surface ◽

Nk Cells ◽

Cd8 T Cells ◽

Nk Cell ◽

Cell Junctions ◽

Cell Surface Receptor ◽

Cytotoxic Lymphocytes

AbstractThe tumor suppressor in lung cancer-1 (TSLC1) gene is frequently silenced in human lung carcinomas, and its expression suppresses tumorigenesis in nude mice. TSLC1 encodes a cell-surface protein called Necl-2 that belongs to the Nectin and Nectin-like (Necl) family of molecules. Necl-2 mediates epithelial cell junctions by homotypic contacts and/or heterotypic interactions with other Nectins and Necls. Thus, it inhibits tumorigenesis by ensuring that epithelial cells grow in organized layers. Here, we demonstrate that natural killer (NK) cells and CD8+ T cells recognize Necl-2 through a receptor known as class I-restricted T-cell–associated molecule (CRTAM), which is expressed only on activated cells. CRTAM–Necl-2 interactions promote cytotoxicity of NK cells and interferon γ (IFN-γ) secretion of CD8+ T cells in vitro as well as NK cell–mediated rejection of tumors expressing Necl-2 in vivo. These results provide evidence for an additional mechanism of tumor suppression mediated by TSLC1 that involves cytotoxic lymphocytes. Furthermore, they reveal Necl-2 as one of the molecular targets that allows the immunosurveillance network to distinguish tumor cells from normal cells.

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Costimulatory Molecule DNAM-1 Is Essential for Optimal NK Education Post Allogeneic Hematopoietic Stem Cell Transplantation

Blood ◽

10.1182/blood-2019-130593 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 3291-3291

Author(s):

Qiannan Shang ◽

Xingxing Yu ◽

Xunhong Cao ◽

Xuefei Liu ◽

Zhengli Xu ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

Hematopoietic Stem Cell Transplantation ◽

Nk Cells ◽

Cd8 T Cells ◽

Nk Cell ◽

Costimulatory Molecule ◽

Point Of View ◽

Post Transplantation ◽

Hematopoietic Stem

Background: DNAM-1 (DNAX accessory molecule-1, CD226) is a costimulatory molecule that is constitutively expressed by NK cells and CD8+ T cells. Interaction between DNAM-1 on NK cells and CD8+ T cells with its ligands on target cells triggers cell-mediated cytotoxicity and cytokine production. Previous mouse model had showed that the expression of DNAM-1 is associated with NK education. Moreover, Monika's group found that DNAM-1 serves as an intrinsic, readout-independent marker for NK cell education in health donor. Our previous study had demonstrated that when both donors and hosts present all the KIR ligands for donor KIRs, reconstituted NK cells would achieve better functional education and contribute to least relapse for the patients post allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the roles of DNAM-1 in NK education post allo-HSCT were unknown. Aims: In this study, we have investigated the contribution of DNAM-1 expression to NK education post transplantation. Methods :We prospectively enrolled 114 patients undergoing haplo-SCT between May 2016 and April 2017 to explore the NK cell dynamic education at days 30, 90 and 180 post-transplant. Peripheral blood mononuclear cells of each sample were analyzed by 15-colors flow cytometry to evaluate of the phenotype as well as functional recovery of NK cells with different maturation expression levels of NKG2A, KIR, and CD57, as well as of activating receptors (NKp30, NKp46, NKG2D, DNAM-1) and CD25, CD122 as well as CD107a and IFN-gamma on NK cells. To study the correlation between the expression of DNAM-1 and effect of donor and host HLA on NK cell education, the expression of DNAM-1 on single-KIR+ NK cells (exhibiting NKG2A, KIR2DL1, KIR2DL2/KIR2DL3, or KIR3DL1 as their sole receptor) was compared based on the combination between donor/host HLA and donor inhibitory KIR. Results: The DNAM-1 expression on single-KIR+ NK cell ligated by sole donor HLA, or sole host HLA, or both donor and host HLA is higher compared to those single-KIR+ NK cells lacking ligands from donor or host or both. From the donor point of view, when donor only presented C1C1 ligand for KIR2DL2/L3, the MFI of DNAM-1 on single KIR2DL2/L3+ NK cells was significantly higher than KIR2DL1+ NK cells and KIR3DL1+ NK cells at 90day (P<0.0001, P=0.046) and 180day (P<0.0001, P=0.034) post transplantation. However, when donor presented C1C1 ligand for KIR2DL2/L3 and Bw4 ligand for KIR3DL1, the MFI of DNAM-1 on single KIR2DL1+ NK cells was significantly lower than KIR2DL2/l3+ NK cells and KIR3DL1+ NK cells at 90day (P<0.0001, P=0.0002) and 180day (P<0.0001, P<0.0001) post transplantation. There was no difference between single KIR2DL1+ NK cells and single KIR3DL1+ NK cells. When donor expressed all HLA(Bw4C1C2) for KIR2DL2/L3, KIR2DL1, KIR3DL1, there was no difference in the expression of DNAM-1 among three single KIR+ NK cells. No matter from the host point or from the combination of donor and host point of view, the DNAM-1 expression differences were same to from donor point of view. There was a clear hierarchy of DNAM-1 expression among NK populations when both of donors and hosts presenting all HLA (Bw4C1C2) for donor KIRs. NK cells with sole KIR or sole NKG2A exhibited higher DNAM-1 expression compared with NKG2A-KIR- NK cells. NK cells with two or three inhibitory KIRs exhibited higher DNAM-1 expression compared with NKG2A+KIR- NK cells. NK cells with 3 inhibitory KIRs and NKG2A expression exhibited maximum DNAM-1 expression at day 30, 90, 180 post transplantation. Meanwhile, the expression of DNAM-1 on NK cells correlated with different ways of education through NKG2A and KIR. There were two fundamental forms of HLA haplotype -21 HLA-B dimorphism: one preferentially supplying CD94:NKG2A ligands (-21M HLA-B), the other preferentially supplying KIR ligands (-21T HLA-B). The expression of DNAM-1 on NKG2A-KIR2DL1+ NK cells was significantly lower when donor or patient was Bw6C1C1 (M/M) compared with when donor or patient was Bw4C2Cx (T/T). However, the expression of DNAM-1 on NKG2A+KIR- NK cells showed no significant difference when donor or patient was Bw6C1C1 (M/M) compared with when donor or patient was Bw4C2C2 (T/T). Summary: This study demonstrated that no matter from donor or/and host point of view, DNAM-1 expression contributes to optimal NK cells education post allo-HSCT. Disclosures No relevant conflicts of interest to declare.

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Natural Killer Cell–Mediated Eradication of Neuroblastoma Metastases to Bone Marrow by Targeted Interleukin-2 Therapy

Blood ◽

10.1182/blood.v91.5.1706.1706_1706_1715 ◽

1998 ◽

Vol 91 (5) ◽

pp. 1706-1715 ◽

Cited By ~ 1

Author(s):

Holger N. Lode ◽

Rong Xiang ◽

Torsten Dreier ◽

Nissi M. Varki ◽

Stephen D. Gillies ◽

...

Keyword(s):

Bone Marrow ◽

T Cells ◽

T Cell ◽

Fusion Protein ◽

Nk Cells ◽

Natural Killer ◽

Therapeutic Effect ◽

Cd8 T Cells ◽

Nk Cell ◽

Interleukin 2

Targeted interleukin-2 (IL-2) therapy with a genetically engineered antidisialoganglioside GD2 antibody–IL-2 fusion protein induced a cell-mediated antitumor response that effectively eradicated established bone marrow and liver metastases in a syngeneic model of neuroblastoma. The mechanism involved is exclusively natural killer (NK) cell–dependent, because NK-cell deficiency abrogated the antitumor effect. In contrast, the fusion protein remained completely effective in the T-cell–deficient mice or immunocompetent mice depleted of CD8+ T cells in vivo. A strong stimulation of NK-cell activity was also shown in vitro. Immunohistology of the leukocytic infiltrate of livers from treated mice revealed a strong staining for NK cells but not for CD8+ T cells. The therapeutic effect of the fusion protein was increased when combined with NK-cell–stimulating agents, such as poly I:C or recombinant mouse interferon-γ. In conclusion, these data show that targeted delivery of cytokines to the tumor microenvironment offers a new strategy to elicit an effective cellular immune response mediated by NK cells against metastatic neuroblastoma. This therapeutic effect may have general clinical implications for the treatment of patients with minimal residual disease who suffer from T-cell suppression after high-dose chemotherapy but are not deficient in NK cells.

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