scholarly journals Post-thymic T lymphocyte maturation during ontogenesis.

1981 ◽  
Vol 154 (3) ◽  
pp. 581-593 ◽  
Author(s):  
P F Piguet ◽  
C Irle ◽  
E Kollatte ◽  
P Vassalli
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Lectin Binding ◽  
T Cell Subsets ◽  
Proliferating Cells ◽  
Peanut Lectin ◽  
Peripheral T Cells

Peripheral T lymphocytes from newborn (4-6-d-old) mice, isolated from the spleen or lymph nodes, show phenotypic features of immature cortical thymocytes, such as high frequencies of proliferating cells and of peanut lectin-binding cells. These are features of peripheral T cells of recent thymic origin, as shown by in situ labeling of thymocytes and subsequent observation of the migrants to the spleen, which were mainly peanut lectin-binding cells. The function of newborn peripheral T cells was compared, on a per T cell basis, with that of thymocytes and of fully mature peripheral T cells of the adult, using preparations of newborn lymph node cells containing approximately 80% of T lymphocytes. They were strikingly (about 10-fold) less competent than adult T cells in their phytohemagglutinin responsiveness, their capacities to induce a graft vs. host reaction, to proliferate in the mixed lymphocyte reaction, and to help B lymphocytes in a humoral response in vivo and in vitro. In contrast, newborn T lymphocytes were comparable to those of adults in their capacity to generate cytotoxic T lymphocytes. No suppressive effect of newborn T lymphocytes could be demonstrated in several of these assays. These results argue for an asynchronous maturation of two T cell subsets during ontogeny and demonstrate that at least some T lymphocytes leave the thymus as immature T cells resembling cortical thymocytes and further mature at the periphery. Investigation of mice submitted to thymectomy of 5 d of age showed that these incompetent post-thymic T lymphocytes are capable of considerable expansion and maturation in the peripheral lymphoid organs in the absence of a thymic influence.

696 Brentuximab vedotin, a CD30-directed antibody-drug conjugate, selectively depletes activated Tregs in vitro and in vivo

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A738-A738
Author(s):  
Bryan Grogan ◽  
Reice James ◽  
Michelle Ulrich ◽  
Shyra Gardai ◽  
Ryan Heiser ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Efflux Pump ◽  
Apoptotic Cell ◽  
T Cell Subsets ◽  
Memory Cells ◽  
Antibody Drug Conjugate ◽  
Selective Depletion

BackgroundRegulatory T cells (Tregs) play an important role in maintaining immune homeostasis, preventing excessive inflammation in normal tissues. In cancer, Tregs hamper anti-tumor immunosurveillance and facilitate immune evasion. Selective targeting of intratumoral Tregs is a potentially promising treatment approach. Orthogonal evaluation of tumor-infiltrating lymphocytes (TILs) in solid tumors in mice and humans have identified CCR8, and several tumor necrosis family receptors (TNFRs), including TNFSFR8 (CD30), as receptors differentially upregulated on intratumoral Tregs compared to normal tissue Tregs and other intratumoral T cells, making these intriguing therapeutic targets.Brentuximab vedotin (BV) is approved for classical Hodgkin lymphoma (cHL) across multiple lines of therapy including frontline use in stage III/IV cHL in combination with doxorubicin, vinblastine, and dacarbazine. BV is also approved for certain CD30-expressing T-cell lymphomas. BV is comprised of a CD30-directed monoclonal antibody conjugated to the highly potent microtubule-disrupting agent monomethyl auristatin E (MMAE).The activity of BV in lymphomas is thought to primarily result from tumor directed intracellular MMAE release, leading to mitotic arrest and apoptotic cell death.The role CD30 plays in normal immune function is unclear, with both costimulatory and proapoptotic roles described. CD30 is transiently upregulated following activation of memory T cells and expression has been linked to highly activated/suppressive IRF4+ effector Tregs.MethodsHere we evaluated the activity of BV on CD30-expressing T cell subsets in vitro and in vivo.ResultsTreatment of enriched T cell subsets with clinically relevant concentrations of BV drove selective depletion of CD30-expressing Tregs > CD30-expressingCD4+ T memory cells, with minimal effects on CD30-expressing CD8+ T memory cells. In a humanized xeno-GVHD model, treatment with BV selectively depleted Tregs resulting in accelerated wasting and robust T cell expansion. The observed differential activity on Tregs is likely attributable to significant increases in CD30 expression and reduced efflux pump activity relative to other T cell subsets. Interestingly, blockade of CD25 signaling prevents CD30 expression on T cell subsets without impacting proliferation, suggesting a link between CD25, the high affinity IL-2 receptor, and CD30 expression.ConclusionsTogether, these data suggest that BV may have an immunomodulatory effect through selective depletion of highly suppressive CD30-expressing Tregs.AcknowledgementsThe authors would like to thank Michael Harrison, PharmD for their assistance in abstract preparation.Ethics ApprovalAnimals studies were approved by and conducted in accordance with Seattle Genetics Institutional Care and Use Committee protocol #SGE-024.

scholarly journals Quantitative assessment of the pool size and subset distribution of cytolytic T lymphocytes within human resting or alloactivated peripheral blood T cell populations.

1983 ◽  
Vol 158 (2) ◽  
pp. 571-585 ◽  
Author(s):  
A Moretta ◽  
G Pantaleo ◽  
L Moretta ◽  
M C Mingari ◽  
J C Cerottini
Keyword(s):  
Monoclonal Antibody ◽  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Peripheral Blood ◽  
Great Majority ◽  
T Cell Subsets ◽  
Cytolytic T Lymphocytes ◽  
Subset Distribution

In order to directly assess the distribution of cytolytic T lymphocytes (CTL) and their precursors (CTL-P) in the two major subsets of human T cells, we have used limiting dilution microculture systems to determine their frequencies. The two subsets were defined according to their reactivity (or lack thereof) with B9.4 monoclonal antibody (the specificity of which is similar, if not identical, to that of Leu 2b monoclonal antibody). Both B9+ and B9- cells obtained by sorting peripheral blood resting T cells using the fluorescence-activated cell sorter (FACS) were assayed for total CTL-P frequencies in a microculture system that allows clonal growth of every T cell. As assessed by a lectin-dependent assay, approximately 30% of peripheral blood T cells were CTP-P. In the B9+ subset (which represents 20-30% of all T cells), the CTL-P frequency was close to 100%, whereas the B9- subset had a 25-fold lower CTL-P frequency. It is thus evident that 90% and 10% of the total CTL-P in peripheral blood are confined to the B9+ or B9- T cell subsets, respectively. Analysis of the subset distribution of CTL-P directed against a given set of alloantigens confirmed these findings. CTL-P frequencies were also determined in B9+ and B9- subsets derived from T cells that had been activated in allogenic mixed leucocyte cultures (MLC). Approximately 10% of MLC T cells were CTL-P. This frequency was increased 3.5-fold in the B9+ subset, whereas the B9- subset contained only a small, although detectable number of CTL-P. Moreover, the great majority of the (operationally defined) CTL-P in MLC T cell population were found to be directed against the stimulating alloantigens, thus indicating a dramatic increase in specific CTL-P frequencies following in vitro stimulation in bulk cultures.

scholarly journals SBF-1 inhibits contact hypersensitivity in mice through down-regulation of T-cell-mediated responses

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Wei Chen ◽  
Xianying Fang ◽  
Yuan Gao ◽  
Ke Shi ◽  
Lijun Sun ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Contact Hypersensitivity ◽  
Immunosuppressive Activity ◽  
Con A ◽  
Activated T Cells ◽  
Picryl Chloride

Abstract Background T lymphocytes play an important role in contact hypersensitivity. This study aims to explore the immunosuppressive activity of SBF-1, an analog of saponin OSW-1, against T lymphocytes in vitro and in vivo. Methods Proliferation of T lymphocytes from lymph nodes of mice was determined by MTT assay. Flow cytometry analysis was performed to assess T cell activation and apoptosis. Levels of cytokines were determined by PCR and ELISA. BALB/c mice were sensitized and challenged with picryl chloride and thickness of left and right ears were measured. Results SBF-1 effectively inhibited T lymphocytes proliferation induced by concanavalin A (Con A) or anti-CD3 plus anti-CD28 at a very low dose (10 nM) but exhibited little toxicity in non-activated T lymphocytes at concentrations up to 10 μM. In addition, SBF-1 inhibited the expression of CD25 and CD69, as well as he phosphorylation of AKT in Con A-activated T cells. SBF-1 also induced apoptosis of activated T cells. In addition, SBF-1 also downregulated the induction of the T cell cytokines, IL-2 and IFN-γ in a dose-dependent manner. Furthermore, SBF-1 significantly suppressed ear swelling and inflammation in a mouse model of picryl chloride-induced contact hypersensitivity. Conclusions Our findings suggest that SBF-1 has an unique immunosuppressive activity both in vitro and in vivo mainly through inhibiting T cell proliferation and activation. Its mechanism appears to be related to the blockage of AKT signaling pathway.

scholarly journals Elimination of syngeneic sarcomas in rats by a subset of T lymphocytes.

1980 ◽  
Vol 152 (4) ◽  
pp. 823-841 ◽  
Author(s):  
E Fernandez-Cruz ◽  
B A Woda ◽  
J D Feldman
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Cell Subset ◽  
Suppressor Cells ◽  
Effector Cells ◽  
Long Duration ◽  
Ia Antigens

Established subcutaneous Moloney sarcomas (MST-1) of large size and long duration were eliminated from syngeneic rats by intravenous infusion of varying numbers of specific syngeneic effector T lymphocytes. Spleen cells from BN rats in which tumor had regressed were cultured in an in vitro mixed lymphocyte tumor cell culture (MLTC) to augment cytotoxicity of effector cells. In the MLTC a T cell subset was expanded in response to MST-1 antigens and transformed into blast elements. With these changes, there was an increase in the W3/25 antigen on the T cell surface, a decrease of W3/13 antigen, and an increase in the number of T cells with Ia antigens. The subset associated with elimination of established tumors was a blast T cell W3/25+, W3/13+, as detected by monoclonal antibodies to rat T antigens. The W3/25+ subset was poorly cytotoxic in vitro for MST-1 and apparently functioned in vivo as an amplifier or helper cell in the tumor-bearing host. The W3/25- population was a melange of cells that included (W3/13+, W3/25-) T cells, null cells, Ig+ cells, and macrophages, and was associated with enhancement of tumor in vivo, suggesting the presence of suppressor cells.

Development of human NKG2D-CD3ε chimeric antigen receptor (CAR) for T-cell-mediated cancer immunotherapy.

2017 ◽  
Vol 35 (7_suppl) ◽  
pp. 150-150
Author(s):  
Sergei Kusmartsev ◽  
Johaness Vieweg ◽  
Victor Prima
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Cells ◽  
Chimeric Antigen Receptor ◽  
Antigen Receptor ◽  
Adaptor Protein ◽  
T Cell Subsets ◽  
Human T Cells

150 Background: NKG2D is a lectin-like type 2 transmembrane receptor that expressed by natural killer cells and some T cell subsets. Stimulation of NKG2D receptor with specific agonistic ligands produces activating signals through signaling adaptor protein DAP10 leading to the enhanced cytokine production, proliferation, and cytotoxicity against tumor cells. There is strong evidence that NKG2D ligands are expressed in many human tumors, including melanoma, leukemia, myeloma, glioma, and carcinomas of the prostate, breast, lung, and colon. Recent studies also demonstrated that T cells bearing chimeric antigen receptor (CAR) NKG2D linked to CD3ζ (zeta) chain produce marked in vitro and in vivo anti-tumor effects. The aim of current study was to determine whether human T cells bearing chimeric antigen receptor (CAR) NKGD2 linked to CD3ε (epsilon) chain could be activated by the NKG2D-specific stimulation and able to kill human cancer cells. Given the important role of CD3ε in activation and survival of T cells, we hypothesized that NKG2D-CDε-bearing T cells could exert strong in vitro and in vivo anti-tumor effects. Methods: NKG2D CAR was produced by linking human NKG2D to DAP10 and the cytoplasmic portion of the CD3ε chain. Original full-length human cDNA clones were obtained from NIH Mammalian Gene Collection (MGC). Functional domain analysis and oligonucleotide design in the in-Fusion system of DNA cloning (Clontech) was used to generate the retroviral expression constructs. Results: Human PBMC-derived T cells were retrovirally transduced with newly generated NKG2D-CD3ε CAR DNA construct. These NKG2D CAR-expressing human T cells responded to NKG2D-specific activation by producing IFN-γ and exhibited significant cellular cytotoxicity against human tumor cells in vitro. In vivo studies demonstrated that NKG2D-CD3ε-bearing cells are capable of inhibiting growth of DU-145 human prostate cancer in the immunodeficient mice. Conclusions: Collectively, our data indicate the feasibility of developing chimeric antigen receptor NKG2D-CD3ε for T cells and suggest that adoptive transfer of T cells bearing NKG2D-CD3ε CAR could be potentially effective for immunotherapy of cancer patients.

Quantitative Assessment of the Impact of Ex Vivo Manipulation on the In Vivo Functionality of Human T Cells in RAG2−/− γc−/− mice.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 450-450
Author(s):  
Rozemarijn S. van Rijn ◽  
Elles R. Simonetti ◽  
Gert Storm ◽  
Mark Bonyhadi ◽  
Anton Hagenbeek ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Ex Vivo ◽  
T Cell Subsets ◽  
Critical Parameters ◽  
In Vivo Evaluation ◽  
Human T Cells ◽  
The Impact

Abstract T cells retrovirally modified to express therapeutic genes encoding cytokines, exogenous TCRs or suicide molecules represent a novel class of immune therapeutics of great potency. However, recent clinical trials using retrovirally-modified T cells have indicated that T cells exhibit a diminished reactivity upon ex vivo manipulation. In addition, virus-specific memory T cells seem to be lost during gene transfer. In a BNML rat model we have shown that the culture procedure is one of the critical parameters. To preserve T cell reactivity, reliable models are required which permit readout of human T cell activity. We recently developed a huPBMC-RAG2−/−γc−/− mouse model for xenogeneic graft-versus-host disease (xGVHD), in which iv injection of 15 x 106 human T cells into RAG2−/−γc−/− mice consistently leads to high level engraftment and lethal xGVHD within 3 weeks in 80% of mice (van Rijn et al, Blood 2003). We have now used this model to analyze in vivo functionality of human T cells following different ex vivo culture procedures. For this, we cultured human T cells for 7 days with either of the two currently available clinically applicable stimulation conditions: 1) via CD3 and 2) via CD3/CD28. In addition, we included CD3/CD28/4-1BB stimulation to explore the effect of extensive costimulation. Mice were injected with escalating doses T cells. HuCD45+ cells in peripheral blood were measured by FACS. Lethal xGVHD occurred at only 6 times (90.106) the dose of fresh cells for CD3-stimulated T cells and 3 times for CD3/28- or CD3/28/4-1BB-stimulated cells. About 20% of surviving mice developed chronic xGVHD, independent of culture method. While lethal xGVHD was always associated with very high levels of engraftment (up to 95%) engraftment levels in chronic mice ranged from 1–75%. To compare the impact of the different culture conditions on in vivo T cell function, we analyzed engraftment potential. The fraction of huCD45+ cells was plotted against the time and the areas under the curves were compared. Based on a total of 68 mice, statistical analysis showed a 2-fold improvement of engraftment potential for C28-costimulated human T cells compared to CD3-stimulated cells (P<0.0001). Additional ligation of 4-1BB did not increase engraftment potential. In addition, different T cell subsets (naïve, memory, effector) were monitored based on the combined expression of CD45RA, CD27 and CCR7. For all primary T cells and variably cultured T cells, a strikingly similar pattern was observed in vivo. After 3 weeks mainly effector and memory effector T cells (both CD4+ and CD8+) could be detected, suggesting a (xeno-)antigen-driven survival and expansion. This was a very consistent observation independent of donor, culture condition, engraftment level or severity of disease. In conclusion, in vitro costimulation preserves in vivo functionality of human T cells and should therefore be included in future clinical protocols for ex vivo manipulation of T cells. These data show the feasibility to use the huPBMC-RAG2−/−γc−/− model for in vivo evaluation of in vitro effects on human T cells. This model is the most sensitive to date for in vivo evaluation of human T cells and will be a promising new tool for the study of human T cells in, for instance, autoimmune disease, cancer and infectious diseases like AIDS.

Cytotoxicity Is Not Required for the Anti-Leukemia Efficacy of Human H-Y-Specific CD4+ T Lymphocytes In Vivo.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3553-3553
Author(s):  
Attilio Bondanza ◽  
Lothar Hambach ◽  
Zohara Aghai ◽  
Monica Casucci ◽  
Bart Nijmeijer ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Cell Clone ◽  
Scid Mice ◽  
Helper T Cell ◽  
T Cell Clone ◽  
Control Clone

Abstract Abstract 3553 Poster Board III-490 Introduction Minor histocompatibility antigens (mHag) play a major role in the graft-versus-leukemia (GvL) effect following HLA-matched allogeneic hemopoietic cell transplantation (allo-HCT). Clinically, the GvL effect coincides with the emergence of mHag-specific CD8+ cytotoxic T lymphocytes (CTL). Experimentally, targeting a single mHag with human CD8+ CTL has a major anti-leukemia effect in NOD/scid mice. Altogether, these observations suggest that mHag-specific cytotoxicity by CD8+ T cells is an important component of the GvL effect. In contrast, little is known on the contribution of mHag-specific CD4+ T cells. Female-to-male allo-HCT is characterized by a low rate of leukemia relapse, indicating that H-Y-encoded mHag are potent leukemia-regression antigens. Earlier, we described a DRB3*0301-restricted H-Y mHag epitope inducing CD4+ helper T-cell responses in H-Y-mismatched HLA-matched allo-HCT. Aim: The aim of this study is to elucidate the role of mHag-specific human CD4+ T lymphocytes on the GvL effect. Methods The ALL-CM leukemia cell line, derived from a male (i.e. H-Y+) HLA-A0201+, DRB30301+ patient, reproducibly engrafts in NOD/scid mice after administration of 10×106 cells. Both an HLA-A0201-restricted H-Y-specific CD8+ CTL clone and the DRB30301-restricted H-Y-specific CD4+ helper T-cell clone that we earlier described were used to investigate the anti-leukemia efficacy of CD8+ and CD4+ T cells in NOD/scid mice. Results In vitro, the CD8+ H-Y specific CTL clone was highly cytotoxic against the ALL-CM leukemia. The H-Y specific CD4+ helper T-cell clone did not lyse the leukemia, but produced IFN-γ upon recognition. Infusion of the H-Y-specific CD8+ CTL clone (25×106 cells/mouse) 3 days after ALL-CM leukemia challenge significantly delayed leukemia progression by 3 weeks compared to a CMV-specific CD8+ CTL control clone (p<0,001). Despite no measurable in vitro cytotoxicity, the H-Y-specific CD4+ helper T-cell clone (25×106 cells/mouse) delayed leukemia progression by 2 weeks compared to a leukemia non-reactive HLA-DR1-specific CD4+ helper T-cell control clone (p<0,001). In vitro co-incubation of the H-Y-specific CD4+ helper T-cell clone did not influence leukemia proliferation but induced up-regulation of MHC-class I and II, CD80, CD86 and CD40. In vitro, pre-incubation of leukemia cells with the H-Y-specific CD4+ helper T-cell clone irradiated did not improve the in vivo anti-leukemia efficacy of the H-Y-specific CD8+ CTL clone. Co-infusion of the H-Y specific CD4+ helper T-cell clone did not augment the in vivo persistence of the H-Y-specific CD8+ CTL T-cell clone. Nevertheless, the co-infusion resulted in a delay in leukemia progression of approximately 5 weeks, suggesting an additive, non overlapping anti-leukemia mechanism. Conclusions Minor Hag-specific human CD4+ T lymphocytes may contribute to the GvL effect through a direct, non cytotoxic mechanism, which could be additive to that of CD8+ CTL. The nature of this non cytotoxic GvL effect is currently under investigation. A.B. and L.H. equally contributed to this study. Disclosures: No relevant conflicts of interest to declare.

In Vitro analysis of Suicide Gene Expression and Function of 3 Suicide Gene-Prodrug Combinations In Human T Lymphocytes Further Modified to Express the CD19 Targeted 19–28z Chimeric Antigen Receptor.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3771-3771
Author(s):  
Jae H. Park ◽  
Raymond Yeh ◽  
Isabelle Rivière ◽  
Michel Sadelain ◽  
Renier J. Brentjens
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Suicide Gene ◽  
Comparable Efficacy ◽  
Suicide Genes ◽  
Human T Lymphocytes ◽  
Drug Concentrations

Abstract Abstract 3771 Adoptive infusion of T cells genetically modified to express chimeric antigen receptors (CARs) targeted to tumor associated antigens (TAAs) is a promising approach to cancer therapy. However, since TAAs are often expressed by normal tissues, safeguards are needed in the form of additional transduced suicide genes to allow for the efficient in vivo abrogation of infused T cells in case of unanticipated adverse events which may develop in the clinical setting. To this end, we have investigated the in vitro function of 3 different suicide genes each inserted distal to a CAR gene targeted against CD19 (19-28z) and a 2A linker peptide cloned into the SFG gammaretroviral vector. Specifically, we have tested the herpes simplex virus thymidine kinase (HSV-TK SR39) with the prodrug ganciclovir, inducible caspase 9 (iCasp9) with the chemical inducer of dimerization (CID), and the E.coli derived nitroreductase (NTR) with the prodrug metronidazole. Cell growth of PG13 murine fibroblasts transduced to express 19–28z CAR with NTR, HSV-TK, and iCasp9 was inhibited by 80% at 1mM of metronidazole, 85% at 1μM of ganciclovir, and 90% at 10nM of CID, respectively, when compared to control PG-13 fibroblasts. The drug concentrations tested in these assays were at physiologically achievable concentrations in humans, and did not affect the growth rate of control PG13 fibroblasts. Consistent with these findings in PG13 fibroblasts, we found that human T cells transduced with either 1928z.2A.NTR or 1928z.2A.HSV-TK demonstrated 90% and 88% inhibition, respectively, at similar substrate concentrations. Furthermore, we demonstrate that expression of these suicide genes does not affect the phenotype or function of the 19–28z CAR+ T cells, as assessed in vitro by T cell proliferation and cytotoxicity against CD19-expressing tumor cells. Our studies demonstrate highly effective suicide genes for human T lymphocytes transduced with a tumor targeted CAR, and a novel suicide gene/prodrug (NTR/metronidazole) combination with a comparable efficacy that can potentially serve as a reliable safety mechanism for adoptive T cell immunotherapy. While HSV-TK/ganciclovir has been utilized in various clinical settings, the NTR suicide gene has yet to be used in combination with gene modified tumor-targeted T cells. Furthermore, the NTR suicide gene holds several advantages over the HSV-TK and iCasp9 vectors. First, unlike HSV-TK, the NTR suicide gene is effective in both proliferating and non-proliferating cells. Second, unlike CID that is not commercially available, metronidazole is a widely available antibiotic that is relatively non-toxic. Lastly, metronidazole can be used in patients who may already be taking ganciclovir for cytomegalovirus (CMV) prophylaxis or treatment therefore limiting the application of T cells modified to express the HSV-TK suicide gene. Based on this in vitro data, we are currently testing the function of this suicide gene in vivo in two different animal models. Ultimately we anticipate that further studies with this novel suicide gene/prodrug combination will allow us to enhance safety in future clinical trials utilizing gene modified tumor targeted T cells. Disclosures: No relevant conflicts of interest to declare.

Activation of T and NK Cells Following Lenalidomide Therapy in Patients with Follicular Lymphoma.

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 2766-2766
Author(s):  
Seema Rawal ◽  
Nathan Fowler ◽  
Min Zhang ◽  
Zhiqiang Wang ◽  
Tariq Muzzafar ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Nk Cells ◽  
Research Funding ◽  
Memory T Cells ◽  
T Cell Subsets ◽  
Central Memory T Cells

Abstract Abstract 2766 Background: Lenalidomide plus rituximab therapy is a highly effective and well-tolerated therapy in patients (pts) with follicular lymphoma (FL). In a Phase II trial, this combination induced a complete remission rate of 87% in pts with advanced stage untreated FL (Fowler et al, Ann Oncol, 2011; 22; suppl 4:137). A randomized Phase III trial was recently initiated to compare this combination with current standard of care therapies in pts with FL. Although lenalidomide is known to be an immunomodulatory drug with effects on a variety of immune cells in vitro, its effects have not been well studied in vivo in humans. Understanding the in vivo effects of lenalidomide could lead to novel combination strategies to enhance the efficacy and improve clinical outcome in FL and other malignancies. Methods: Pts received lenalidomide 20 mg/day on days 1–21 of each 28-day cycle and rituximab was given at 375 mg/m2on day 1 of each cycle. Peripheral blood mononuclear cells (PBMC) were phenotyped by multiparametric flow cytometry at baseline, on cycle 2 day 15 (C2D15), and at the end of cycle 6. In addition, peripheral blood (PB) samples were collected in PAXgene Blood RNA tubes at baseline and on C2D15 for whole genome gene expression profiling (GEP). Results: Immunophenotyping of baseline and end of cycle 6 PBMC (n=17) showed that the percentages and absolute numbers of CD3+, CD4+, CD8+, TCRgd, and Foxp3+ regulatory T cells; and NK, NKT, and myeloid dendritic cells were not significantly different between the two time points. However, a significant increase in CD4+CD45RO+ (p<0.01) and CD8+CD45RO+ (p=0.04) memory T cells was observed post-therapy. Further characterization of CD4+ T cells showed a significant increase in central memory T cells (p<0.001) and a decrease in naïve (p<0.01) and terminally differentiated (p<0.01) T cells, but no change in effector memory T cells. The increase in CD8+ central memory T cells was marginally significant (p=0.06). Plasmacytoid dendritic cells (PDC) were also significantly increased (p=0.02). In contrast, no such changes in T cell subsets or PDC were observed in FL pts (n=9) treated with 6 cycles of R-CHOP chemotherapy that received equal number of rituximab doses and analyzed at similar time points (baseline and end of cycle 6). To understand lenalidomide-induced changes on a molecular level, we compared GEP data at C2D15 vs. baseline for 7 pairs of PB samples. The paired significance analysis of microarrays method, based on Student's t test, identified 1,748 differentially expressed genes (DEG; 713 up, 1035 down), without a fold-change threshold, in C2D15 samples vs. baseline. Results were influenced by rituximab-induced depletion of B cells in C2D15 samples, but there were many changes that suggested altered PBMC physiology. Noteworthy up-regulated genes (>1.5 fold) included genes associated with T and NK cell activation including BATF, CCR2, CD1B, CD2, CD160, CTLA4, CXCR3, ICOS, and LAG3; and CD163 and CD209, phagocytic receptors expressed on monocytes/macrophages. Down-regulated genes (>1.5 fold) included CXCR5, which mediates B cell migration into follicles; and IL1B and TNFSF13B (BAFF), which are produced by activated macrophages and induce B cell proliferation. Gene set enrichment analysis of all GEP results, and Ingenuity Pathway Analysis of DEGs, indicated up regulation of multiple pathways and processes including ribosomal and mitochondrial components involved in translation and oxidative phosphorylation, CTLA4 signaling in cytotoxic T cells, and differentiation and signaling by ICOS and CD28 in T helper cells. We confirmed up regulation of CTLA4, ICOS, and LAG3 at the protein level in C2D15 PBMC by flow cytometry. Furthermore, treatment of PBMC derived from untreated FL pts with lenalidomide in vitro resulted in up regulation of these molecules in T and/or NK cells consistent with our in vivo results. Conclusions: In FL pts, lenalidomide induced multiple changes in the immune system including increases in PDC and memory T cell subsets, activation of T and NK cells, and down-regulation of certain genes mediating B cell migration and proliferation. These results provide insights into the mechanism of action of lenalidomide and suggest that it can be combined with other immunostimulatory agents such as therapeutic vaccines, adoptive T cell therapy strategies, and immune checkpoint inhibitors to further enhance its efficacy in FL and other malignancies. Disclosures: Fowler: Celgene: Research Funding. Heise:Celgene Corporation: Employment, Equity Ownership. Lacerte:Celgene: Honoraria. Samaniego:Celgene: Research Funding. Neelapu:Celgene Corporation: Research Funding.

Cortisol increases CXCR4 expression but does not affect CD62L and CCR7 levels on specific T cell subsets in humans

2014 ◽  
Vol 306 (11) ◽  
pp. E1322-E1329 ◽  
Author(s):  
Luciana Besedovsky ◽  
Barbara Linz ◽  
Stoyan Dimitrov ◽  
Sabine Groch ◽  
Jan Born ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
Lymph Node ◽  
T Cell ◽  
Cxcr4 Expression ◽  
T Cell Subsets ◽  
Lymph Node Homing ◽  
Endogenous Cortisol

Glucocorticoids are well known to affect T cell migration, leading to a redistribution of the cells from blood to the bone marrow, accompanied by a concurrent suppression of lymph node homing. Despite numerous studies in this context, with most of them employing synthetic glucocorticoids in nonphysiological doses, the mechanisms of this redistribution are not well understood. Here, we investigated in healthy men the impact of cortisol at physiological concentrations on the expression of different migration molecules on eight T cell subpopulations in vivo and in vitro. Hydrocortisone (cortisol, 22 mg) infused during nocturnal rest when endogenous cortisol levels are low, compared with placebo, differentially reduced numbers of T cell subsets, with naive CD4+ and CD8+ subsets exhibiting the strongest reduction. Hydrocortisone in vivo and in vitro increased CXCR4 expression, which presumably mediates the recruitment of T cells to the bone marrow. Expression of the lymph node homing receptor CD62L on total CD3+ and CD8+ T cells appeared reduced following hydrocortisone infusion. However, this was due to a selective extravasation of CD62L+ T cell subsets, as hydrocortisone affected neither CD62L expression on a subpopulation level nor CD62L expression in vitro. Corresponding results in the opposite direction were observed after blocking of endogenous cortisol synthesis by metyrapone. CCR7, another lymph node homing receptor, was also unaffected by hydrocortisone in vitro. Thus, cortisol seems to redirect T cells to the bone marrow by upregulating their CXCR4 expression, whereas its inhibiting effect on T cell homing to lymph nodes is apparently regulated independently of the expression of classical homing receptors.

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