Role of STAT3 and Th17 Cells in Cutaneous T Cell Lymphoma

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 66-66
Author(s):  
Swati Goel ◽  
Laura K Fogli ◽  
Mark Sundrud ◽  
Stefano Casola ◽  
Klaus Rajewsky ◽  
...  

Abstract Abstract 66 Background Cutaneous T cell Lymphoma (CTCL) is a heterogeneous group of non-Hodgkin's lymphomas characterized by skin-homing malignant T cells. The etiology of CTCL remains enigmatic, but constitutive Signal Transducer and Activator of Transcription 3 (STAT3) activity is characteristic of this malignancy. CTCL cell lines undergo growth arrest and apoptosis following inhibition of STAT3 signaling, suggesting that STAT3 may be a pro-survival factor in these cells. STAT3 phosphorylation is also required for the initiation and maintenance of the Th17 differentiation program, a recently identified subset of CD4+ T helper cells, implicated in a number of chronic inflammatory conditions including rheumatoid arthritis and psoriasis. Furthermore, we know that Histone Deacetylase inhibitors (HDACi) namely Vorinostat and Romidepsin are very active agents for treatment of CTCL but their mechanism of action is still to be elucidated. Our goal is to probe the contribution of Th17 mediated inflammation in CTCL and to examine whether HDAC inhibitors work by modulating Th17 inflammation in the context of this malignancy. Methods Using conditional gene targeting approach we have generated a transgenic 100% penetrant mouse model of CTCL wherein expression of a hyper-active STAT3 mutant protein (STAT3C) selectively in T lymphocytes results in skin pathology highly reminiscent of this human malignancy. To have a better understanding of the contribution of STAT3 in CD4 T cell differentiation program and CTCL, we used lymphocytes and splenocytes from 8 weeks old STAT3Cstopfl/fl (without CD4Cre, thus no pathology) and control YFPstopfl/fl (Yellow Fluorescent Protein floxed) mice (Figure 1a). We isolated naïve CD4 cells using Dynabeads and treated these CD4 cells with a transducible Cre enzyme (Tat-Cre) to delete the upstream stop cassette ex-vivo. These cells were then plated with stimulating α CD3/CD28 antibodies in various cytokine cocktails as shown in Figure 1b. These cells were harvested after 84 hours and stimulated with PMA/Inomycin for 4 hours for flowcytometric analysis. We are now using this in-vitro approach as well as our mouse model and primary tissue samples from CTCL patients to explore the impact of HDAC inhibitors on Th17/Treg balance. Results Upon Tat-Cre treatment we were able to analyze GFP+ (and therefore STAT3C expressing) vs. GFP- (control) T cells in the same differentiation conditions. Hyperactive STAT3C mutant protein favored TH17 differentiation as GFP Positive cells had significantly augmented IL17A production (Figure 1b). On the other hand, STAT3C expressing GFP positive cells in Th0 and Th1 differentiation conditions had less IFN-γ production compared to the GFP negative cells and control YFP fractions. Even the GFP negative fraction of STAT3C had less IFN-γ and more IL17A production than the control YFP fractions due to the cytokine milieu created by STAT3C expressing cells present in the same well. Conclusions: These results highlight an intriguing possibility that STAT3 dependent Th17 cells play a role in CTCL pathogenesis. Using our newly developed mouse model and CTCL patients' blood and skin samples (IRB approved), we are trying to distinguish whether Th17 cells are instigators of chronic inflammation that contributes to the malignant transformation of T cells or that Th17 cells may actually be the cells of origin in this malignancy. Our ongoing experiments also include the effects of HDACi on this ex-vivo CD4 T cell differentiation. In addition, we are studying the hallmarks of Th17 differentiation namely IL-17A, IL-22 and pSTAT3 positivity in the skin biopsy and blood samples of CTCL patients before and after treatment with HDACi. These experiments will help us determine the impact of HDAC inhibition on STAT3 activity and Th17 differentiation and have a better understanding of their mechanism of action in CTCL. Our hope is that our study will guide us to comprehend the contribution of chronic inflammation in carcinogenesis and potentially identify novel treatment targets and strategies in the field of hematological malignancies. Disclosures: No relevant conflicts of interest to declare.

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3755-3755 ◽  
Author(s):  
Swati Goel ◽  
Laura K Fogli ◽  
Amy Sun ◽  
Melania Fanok ◽  
Niels Odum ◽  
...  

Abstract Phosphorylation of signal transducer and activator of transcription 3 (STAT3) is essential for cell survival, proliferation and differentiation. STAT3 phosphorylation results from signaling by cytokines and growth factors, and constitutive STAT3 activity is characteristic of a number of human malignancies, including Cutaneous T Cell Lymphoma (CTCL). Furthermore, we now know that STAT3 is also required for the initiation and maintenance of the Th17 differentiation program. Th17 cells are a subset of CD4 T helper cells that have been implicated in chronic inflammatory conditions like rheumatoid arthritis and psoriasis. Mycosis fungoides (MF) and the leukemic variant of this disease, Sezary syndrome (SS), are the most frequently encountered forms of CTCL and in both of these diseases, the cell of origin – as far as the type of Teffector cell involved, has not been defined. Recent results from our laboratory and that of our colleagues have lead us to believe that Th17 cells may either be the cells of origin in CTCL or may act as critical mediators of chronic inflammation that creates a favorable environment for tumor growth in the context of this malignancy. In an effort to elucidate the role of STAT3 as a transforming factor in T cell malignancies, we generated a mouse model wherein T cell specific expression of a hyper-active STAT3 mutant protein (STAT3C) leads to the development of a lymphoproliferative disease that is highly reminiscent of CTCL. We are now taking advantage of this unique mouse model, patient biospecimens and carefully characterized CTCL cell lines to dissect the role of STAT3 signaling cascade in the malignant transformation and maintenance of CTCL. Most recently, our attention has been focused on understanding the mechanism of action of epigenetic therapy in the form of histone deacetylase inhibitors (HDACi), which is highly effective in the treatment of CTCL. We hypothesize that HDAC inhibitors affect the STAT3 mediated Th17 differentiation and thus have clinical efficacy in this disease. In addition to the regulation of chromatin accessibility through the regulation of histone modifications, HDACi have also been implicated in a less conventional mode of protein regulation directly influencing STAT3 serine phosphorylation. To dissect the action of HDACi on malignant cells, we took advantage of CTCL cell lines and cultured these with and without Romidepsin, which is an effective HDAC inhibitor used in clinic. MyLa2059 and PB2B are MF cell lines with skin only phenotype whereas SeAx and SeZ4 are SS cell lines. The cells were cultured for 48 hours with no Romidepsin, 5nm and 50 nm Romidepsin. After 48 hours, cells were fixed and permeabilized using BD fix-perm protocol. Cells were then stained to assess Serine 727 STAT3 and Tyrosine Y705 STAT3 phosphorylation and analyzed using flowcytometry. We found that Romidepsin affected serine phosphorylation exclusively in CTCL cell lines (Figure 1). This leads us to believe that STAT3 serine phosphorylation might play an important role in lymphomagenesis and can act as a potential therapeutic target. The role of serine phosphorylation in the context of STAT3 signaling is hotly debated and we are now attempting to characterize the role of Serine STAT3 phosphorylation in the context of CTCL. We are also hoping to recapitulate these observations in patients' biospecimens collected before and after treatment with HDAC inhibitors. We will also study the role of serine phosphorylation in STAT3 activity in carcinogenesis using our mouse model with phenotypic and pathological characteristics similar to CTCL. We hope that these studies will advance our knowledge about the role that Stat 3 signaling plays in MF/SS malignant transformation and cancer progression and help us develop target specific treatment options for the clinical practice. Disclosures: Hymes: Celgene: Consultancy.


2021 ◽  
Vol 9 (6) ◽  
pp. e002269
Author(s):  
Shota Aoyama ◽  
Ryosuke Nakagawa ◽  
Satoshi Nemoto ◽  
Patricio Perez-Villarroel ◽  
James J Mulé ◽  
...  

BackgroundThe temporal response to checkpoint blockade (CB) is incompletely understood. Here, we profiled the tumor infiltrating lymphocyte (TIL) landscape in response to combination checkpoint blockade at two distinct timepoints of solid tumor growth.MethodsC57BL/6 mice bearing subcutaneous MC38 tumors were treated with anti-PD-1 and/or anti-CTLA-4 antibodies. At 11 or 21 days, TIL phenotype and effector function were analyzed in excised tumor digests using high parameter flow cytometry. The contributions of major TIL populations toward overall response were then assessed using ex vivo cytotoxicity and in vivo tumor growth assays.ResultsThe distribution and effector function among 37 distinct TIL populations shifted dramatically between early and late MC38 growth. At 11 days, the immune response was dominated by Tumor necrosis factor alpha (TNFα)-producing NKT, representing over half of all TIL. These were accompanied by modest frequencies of natural killer (NK), CD4+, or CD8+ T cells, producing low levels of IFN-γ. At 21 days, NKT populations were reduced to a combined 20% of TIL, giving way to increased NK, CD4+, and CD8+ T cells, with increased IFN-γ production. Treatment with CB accelerated this switch. At day 11, CB reduced NKT to less than 20% of all TIL, downregulated TNFα across NKT and CD4+ T cell populations, increased CD4+ and CD8+ TIL frequencies, and significantly upregulated IFN-γ production. Degranulation was largely associated with NK and NKT TIL. Blockade of H-2kb and/or CD1d during ex vivo cytotoxicity assays revealed NKT has limited direct cytotoxicity against parent MC38. However, forced CD1d overexpression in MC38 cells significantly diminished tumor growth, suggesting NKT TIL exerts indirect control over MC38 growth.ConclusionsDespite an indirect benefit of early NKT activity, CB accelerates a switch from TNFα, NKT-driven immune response toward an IFN-γ driven CD4+/CD8+ T cell response in MC38 tumors. These results uncover a novel NKT/T cell switch that may be a key feature of CB response in CD1d+ tumors.


2018 ◽  
Vol 92 (16) ◽  
Author(s):  
Pritesh Desai ◽  
Vikas Tahiliani ◽  
Georges Abboud ◽  
Jessica Stanfield ◽  
Shahram Salek-Ardakani

ABSTRACTRespiratory infection with vaccinia virus (VacV) elicits robust CD8+T cell responses that play an important role in host resistance. In the lung, VacV encounters multiple tissue-resident antigen-presenting cell (APC) populations, but which cell plays a dominant role in priming of virus-specific CD8+effector T cell responses remains poorly defined. We used Batf3−/−mice to investigate the impact of CD103+and CD8α+dendritic cell (DC) deficiency on anti-VacV CD8+T cell responses. We found that Batf3−/−mice were more susceptible to VacV infection, exhibiting profound weight loss, which correlated with impaired accumulation of gamma interferon (IFN-γ)-producing CD8+T cells in the lungs. This was largely due to defective priming since early in the response, antigen-specific CD8+T cells in the draining lymph nodes of Batf3−/−mice expressed significantly reduced levels of Ki67, CD25, and T-bet. These results underscore a specific role for Batf3-dependent DCs in regulating priming and expansion of effector CD8+T cells necessary for host resistance against acute respiratory VacV infection.IMPORTANCEDuring respiratory infection with vaccinia virus (VacV), a member ofPoxviridaefamily, CD8+T cells play important role in resolving the primary infection. Effector CD8+T cells clear the virus by accumulating in the infected lungs in large numbers and secreting molecules such as IFN-γ that kill virally infected cells. However, precise cell types that regulate the generation of effector CD8+T cells in the lungs are not well defined. Dendritic cells (DCs) are a heterogeneous population of immune cells that are recognized as key initiators and regulators of T-cell-mediated immunity. In this study, we reveal that a specific subset of DCs that are dependent on the transcription factor Batf3 for their development regulate the magnitude of CD8+T cell effector responses in the lungs, thereby providing protection during pulmonary VacV infection.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1959-1959
Author(s):  
Jeong A Park ◽  
Hong fen Guo ◽  
Hong Xu ◽  
Nai-Kong V. Cheung

Background Ex Vivo Armed T-cells (EVAT) carrying zeptomoles (10-21M) of T-cell engaging GD2-bispecific antibody (GD2-EVAT) or HER2-bispecific antibodies (HER2-EVAT) have potent anti-tumor activity against GD2(+) and/or HER2(+) solid tumors. Strategies to further optimize this approach are highly relevant. PD-1 is a key immune checkpoint receptor expressed mainly by activated T-cells and mediates immune suppression by binding to its ligands PD-L1 or PD-L2. Upregulation of PD-L1 has been found in many cancers including osteosarcoma and associated with aggressive disease and poor outcome. While the use of immune checkpoint inhibitors (ICIs) seems logical, the ideal timing when combined with T-cell engaging bispecific antibody (T-BsAb) or EVAT has yet to be defined. Here, we described the effects of anti-PD-1 or anti-PD-L1 antibodies on GD2-EVAT or HER2-EVAT therapy and explored the impact of its timing in the treatment of osteosarcoma which is GD2(+), HER2(+) and PD-L1(+). Methods GD2-BsAb and HER-BsAb were built using the IgG(L)-scFv format (Can Immunol Res, 3:266, 2015, Oncoimmunology, PMID:28405494). T-cells from healthy volunteer donors were isolated, and cultured ex vivo in the presence of CD3/CD28 beads plus 30 IU/mL of interleukin 2 (IL-2). Between day 7 and day 14, activated T-cells (ATCs) were harvested and armed for 20 minutes at room temperature with GD2-BsAb or HER2-BsAb. In vivo anti-tumor activity against GD2(+), HER2(+), and PD-L1(+) osteosarcoma cell line xenografts was tested in BALB-Rag2-/-IL-2R-γc-KO mice. Anti-human PD-1 antibody (pembrolizumab, anti-PD-1) or anti-human PD-L1 antibody (atezolizumab, anti-PD-L1) were tested for synergy with GD2-EVAT or HER2-EVAT therapy. Results The PD-1 expression increased among T-cells that circulated in the blood, that infiltrated the spleen or the tumor after EVAT therapy. While anti-PD-L1 combination therapy with GD2-EVAT or HER2-EVAT improved anti-tumor response against osteosarcoma (P=0.0123 and P=0.0004), anti-PD-1 did not (all P>0.05). The addition of anti-PD-L1 significantly increased T-cell survival in blood and T-cell infiltration of tumor when compared to GD2-EVAT or HER2-EVAT alone (all P<0.0001). Treatment of GD2-EVAT or anti-PD-L1 plus GD2-EVAT downregulated GD2 expression on tumors, but anti-PD-1 plus GD2-EVAT did not. For the next step we tested the impact of different combination schedules of ICIs on GD2-EVAT therapy. Concurrent anti-PD-1 (6 doses along with GD2-EVAT therapy) interfered with GD2-EVAT, while sequential anti-PD-1 (6 doses after GD2-EVAT) did not make a significant effect (P>0.05). On the other hand, while the concurrent use of anti-PD-L1 did not show benefit on GD2-EVAT, sequentially administered anti-PD-L1 produced a significant improvement in tumor control when compared to anti-PD-L1 or GD2-EVAT alone (P=0.002 and P=0.018). When anti-PD-L1 treatment was extended (12 doses after GD2-EVAT), the anti-tumor effect was most pronounced compared to GD2-EVAT alone (P <0.0001), which translated into improved survival (P=0.0057). These in vivo anti-tumor responses were associated with increased CD8(+) tumor infiltrating lymphocytes (TILs) of tumor. Conclusion In the arming platform, large numbers of target-specific T-cells can be generated, and this EVAT therapy is a highly effective cellular treatment with high potency in preclinical models. In addition, the advantage of ex vivo cytokine release following T-cell arming and activation could reduce or avoid life threatening cytokine storm if such activation was to proceed in vivo. Adoptive T-cell therapy induced immune response upregulates the inhibitory immune checkpoint PD-1/PD-L1 pathway, and combination treatment with anti-PD-L1 antibody, especially when combined as sequential therapy and continuously treated, significantly improved anti-tumor effect of EVAT, partly through increase in CD8(+) TILs infiltration. Disclosures Xu: MSK: Other: co-inventors in patents on GD2 bispecific antibody and HER2 bispecific antibody. Cheung:Ymabs: Patents & Royalties, Research Funding.


1998 ◽  
Vol 66 (10) ◽  
pp. 4981-4988 ◽  
Author(s):  
Irina Lyadova ◽  
Vladimir Yeremeev ◽  
Konstantin Majorov ◽  
Boris Nikonenko ◽  
Sergei Khaidukov ◽  
...  

ABSTRACT I/St mice, previously characterized as susceptible toMycobacterium tuberculosis H37Rv, were given 103 or 105 CFU intravenously. At two time points postinoculation, the cell suspensions that resulted from enzymatic digestion of lungs were enumerated and further characterized phenotypically and functionally. Regarding the T-cell populations recovered at 2 and 5 weeks postinfection, two main results were obtained: (i) the population of CD44− CD45RB+cells disappeared within 2 weeks postinfection, while the number of CD44+ CD45RB−/low cells slowly increased between weeks 2 and 5; (ii) when cocultured with irradiated syngeneic splenocytes, these lung T cells proliferated in the presence of H37Rv sonicate. Using H37Rv sonicate and irradiated syngeneic splenocytes to reactivate lung T cells, we selected five CD3+CD4+ CD8− T-cell clones. In addition to the H37Rv sonicate, the five clones react to both a short-term culture filtrate and an affinity-purified 15- to 18-kDa mycobacterial molecule as assessed by the proliferative assay. However, there was a clear difference between T-cell clones with respect to cytokine (gamma interferon [IFN-γ] and interleukin-4 [IL-4] and IL-10) profiles: besides one Th1-like (IFN-γ+ IL-4−) clone and one Th0-like (IFN-γ+ IL-4+IL-10+) clone, three clones produced predominantly IL-10, with only marginal or no IL-4 and IFN-γ responses. Inhibition of mycobacterial growth by macrophages in the presence of T cells was studied in a coculture in vitro system. It was found that the capacity to enhance antimycobacterial activity of macrophages fully correlated with INF-γ production by individual T-cell clones following genetically restricted recognition of infected macrophages. The possible functional significance of cytokine diversity among T-cell clones is discussed.


2019 ◽  
Vol 13 (7) ◽  
pp. 905-915 ◽  
Author(s):  
Shrinivas Bishu ◽  
Mohammed El Zaatari ◽  
Atsushi Hayashi ◽  
Guoqing Hou ◽  
Nicole Bowers ◽  
...  

Abstract Background and Aims Tumour necrosis factor [TNF]α- and IL-17A-producing T cells are implicated in Crohn’s disease [CD]. Tissue-resident memory T [TRM] cells are tissue-restricted T cells that are regulated by PR zinc finger domain 1 [PRDM1], which has been implicated in pathogenic Th17 cell responses. TRM cells provide host defence but their role in CD is unknown. We thus examined CD4+ TRM cells in CD. Methods Colon samples were prospectively collected at endoscopy or surgery in CD and control subjects. Flow cytometry and ex vivo assays were performed to characterise CD4+ TRM cells. Results CD4+ TRM cells are the most abundant memory T cell population and are the major T cell source of mucosal TNFα in CD. CD4+ TRM cells are expanded in CD and more avidly produce IL-17A and TNFα relative to control cells. There was a unique population of TNFα+IL-17A+ CD4+ TRM cells in CD which are largely absent in controls. PRDM1 was highly expressed by CD4+ TRM cells but not by other effector T cells. Suppression of PRDM1 was associated with impaired induction of IL17A and TNFA by CD4+ TRM cells Conclusions CD4+ TRM cells are expanded in CD and are a major source of TNFα, suggesting that they are important in CD. PRDM1 is expressed by TRM cells and may regulate their function. Collectively, this argues for prospective studies tracking CD4+ TRM cells over the disease course.


2020 ◽  
Vol 4 (17) ◽  
pp. 4195-4207
Author(s):  
Shih-Feng Cho ◽  
Liang Lin ◽  
Lijie Xing ◽  
Yuyin Li ◽  
Kenneth Wen ◽  
...  

Abstract We investigated here the novel immunomodulation and anti–multiple myeloma (MM) function of T cells engaged by the bispecific T-cell engager molecule AMG 701, and further examined the impact of AMG 701 in combination with immunomodulatory drugs (IMiDs; lenalidomide and pomalidomide). AMG 701 potently induced T-cell–dependent cellular cytotoxicity (TDCC) against MM cells expressing B-cell maturation antigen, including autologous cells from patients with relapsed and refractory MM (RRMM) (half maximal effective concentration, &lt;46.6 pM). Besides inducing T-cell proliferation and cytolytic activity, AMG 701 also promoted differentiation of patient T cells to central memory, effector memory, and stem cell–like memory (scm) phenotypes, more so in CD8 vs CD4 T subsets, resulting in increased CD8/CD4 ratios in 7-day ex vivo cocultures. IMiDs and AMG 701 synergistically induced TDCC against MM cell lines and autologous RRMM patient cells, even in the presence of immunosuppressive bone marrow stromal cells or osteoclasts. IMiDs further upregulated AMG 701–induced patient T-cell differentiation toward memory phenotypes, associated with increased CD8/CD4 ratios, increased Tscm, and decreased interleukin 10–positive T and T regulatory cells (CD25highFOXP3high), which may downregulate T effector cells. Importantly, the combination of AMG 701 with lenalidomide induced sustained inhibition of MM cell growth in SCID mice reconstituted with human T cells; tumor regrowth was eventually observed in cohorts treated with either agent alone (P &lt; .001). These results strongly support AMG 701 clinical studies as monotherapy in patients with RRMM (NCT03287908) and the combination with IMiDs to improve patient outcomes in MM.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 5273-5273
Author(s):  
Qi Sun ◽  
Karen Chorney ◽  
Carol Stine ◽  
Kenneth G. Lucas

Abstract Adoptive T cell immunotherapy (ATCI) is an evolving strategy that explores antigen-specific T cells manipulated ex vivo as therapeutic agents. Although the concept of ATCI has been tested clinically, with success in the treatment of post-transplant EBV induced lymphoproliferative disease, one of the major obstacles hindering its application to other malignancies is the procurement of tumor-specific T cells that possess potent anti-tumor functions even in the inhibitory environment at the tumor sites. This study aims to genetically engineer enriched viral specific T cells for improved immune functions. A self-inactivating lentiviral vector (SIN) CD69p-IL2 was constructed to encode the transgene interleukin-2 (IL2) under the control of a human CD69 promoter (CD69p), and this vector was tested in ex vivo cultivated EBV-specific T cells. SIN vector allows a high degree of autonomy for the internal promoter, and CD69 expression in the T cells is closely associated with T cell activation. Experiments showed that the SIN vectors efficiently transduced EBV-specific T cells, both CD4 and CD8. Furthermore, the newly cloned CD69p exhibited a higher degree of responsiveness to physiological antigen stimulation than the early promoter from the cytomegalovirus (CMVp). In response to stimulation by EBV-infected B cells, the percentage of IL2 expressing cells was 2 fold higher for the activated CD69p-IL2 transduced T cells than the non-transduced, or the CMVp-IL2 transduced, counterparts. In correlation with the stronger IL2 expression, 3 fold more T cells expressed the anti-viral cytokine interferon-γ (IFN-γ) in the CD69p-IL2 transduced T cells than the CMVp-IL2 transduced, and the IFN-γ expression at the single cell level was 2 fold higher in the former, indicating an enhanced functionality. While the culture supernatant from the CMVp-IL2 transduced T cells contained IL2 at a concentration 2000 fold higher than the non-transduced T cells, the IL2 level in the media from the CD69p-IL2 transduced T cells was comparable to that in the control, suggesting the IL2 expression mediated by the CD69p more relevant to T cell functions than the CMVp. These results may serve as a foundation for the further development and clinical application of specific T cells engineered for enhanced immune functions.


Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3106-3106
Author(s):  
Bruno Nervi ◽  
Michael P. Rettig ◽  
Julie K. Ritchey ◽  
Gerhard Bauer ◽  
Jon Walker ◽  
...  

Abstract GvHD remains a major cause of morbidity and mortality following allogeneic hematopoietic stem cell transplantation and donor lymphocyte infusion. The human GvHD pathophysiology includes recipient tissue destruction and proinflammatory cytokine production associated with the conditioning regimen; donor T cells become allo-activated, proliferate, and mediate tissue injury in various organs, including the liver, skin, and gut. Modern therapeutic strategies to control GvHD while maintaining the beneficial graft-versus-leukemia effects require ex vivo T cell stimulation and expansion. Multiple studies have demonstrated that these ex vivo expanded T cells exhibit decreased survival and function in vivo, including reduced alloreactivity and GvHD potential. Unfortunately no in vivo models exist to consistently examine the impact of ex vivo manipulation of human T cells (HuT) on T cell function. Naive HuT were compared to HuT activated using CD3/28 beads (XcyteTMDynabeads) with 50 U/ml IL-2 for 4 days (Act). We initially evaluated the HuT engraftment and GvHD potential of naive and Act in RAG2γ null mice (n=22) conditioned with clodronate liposomes on day −1 and 350cGy on day 0, as previously described by others. We injected 107 and 1.5x107 naive or Act HuT intravenously (iv). All mice exhibited low HuT engraftment and no lethal GvHD. NOD SCIDβ 2M null mice (β 2M) were next conditioned with 250cGy on day −1 (n=34), or 300cGy on day 0 (n=21). 107 naive vs Act HuT were injected retroorbitaly (ro). Lower HuT doses or iv injection resulted in no expansion or GvHD. Engraftment of HuT in peripheral blood of recipient mice was evaluated weekly by FACS and euthanasia was performed if mice lost &gt; 20% body weight. 60% of the mice conditioned with 250cGy that received naive HuT developed lethal GvHD, in comparison to 75% of mice that received 300cGy and nave HuT, and 100% of mice that received 300cGy and Act HuT. Table 1 250cGy 300cGy Naive (n=34) Naive (n=8) Activated (n=13) *p&lt;0.02 PB engraftment (%HuT) 20%±15 33%±21 59%±19 Lethal GvHD 60% 75% 100% All mice receiving 300cGy had well preserved CD4/CD8 ratios (1–1.5). Tissue infiltration was greatest in mice that had received 300cGy and Act HuT (spleen, liver, lung, kidney: 50–70%). Of interest, serum levels of hu IFNγ dramatically increased over time in all mice who went on to develop lethal GvHD (day 3=270 ug/ml and day 15=36,000 ug/ml) compared to mice that did not develop lethal GvHD (day 10=40 ug/ml and day 17=1,020 ug/ml)(p&lt;0.05). Interestingly, the up-regulation of the activation markers CD25 and CD30 in HuT, and IFNγ production predicted lethal GvHD in β 2M null mice. In summary, we developed a xenogeneic model of lethal GvHD where naive or ex vivo Act HuT injected ro in sublethaly irradiated β 2M not only engraft, expand in vivo, but also infiltrate and damage different mouse target organs. HuT are allo-activated against mouse antigens and damage the target tissues, sharing the major characteristics of human GvHD and causing the death of mice. This model will allow us to study the effects of specific ex vivo T cell manipulation including transduction, selection, expansion, and the depletion or addition of various T cells and other cellular subsets on the outcome of GvHD, to determine improved therapeutic interventions.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 769-769 ◽  
Author(s):  
Aaron P. Rapoport ◽  
Stephan A. Grupp ◽  
Edward A. Stadtmauer ◽  
Robert H. Vonderheide ◽  
Bruce L. Levine ◽  
...  

Abstract Retrospective studies suggest that rapid lymphocyte recovery following autologous stem cell transplants (SCT) may be associated with better outcomes. Previously we showed that adoptive transfer of in-vivo vaccine-primed and ex-vivo (anti-CD3/anti-CD28) costimulated autologous T cells (ex-T) at about day 14 post-transplant increased CD4 and CD8 T cell counts at day 42 post-transplant and induced pneumococcal conjugate vaccine-directed T and B-cell responses [Rapoport et al, Nature Medicine, 2005]. In 2 current studies, we are further investigating the impact of ex-vivo costimulated autologous T cells on vaccine responses after SCT. In the first study, we are investigating whether a similar strategy of pre- and post-transplant immunizations along with an early infusion of vaccine-primed ex-T can induce responses to a putative tumor vaccine composed of 4 HLA-A2-restricted peptides derived from survivin and hTERT in pts undergoing SCT for myeloma. In the second (randomized) trial, the impact of early ex-T on immune recovery and vaccine reponses is being tested in pediatric neuroblastoma pts. Compared to the previous study, two methodologic changes were made: The target number of T cells infused was raised 5-fold to 5 x 1010 (109/kg) T cells were infused on day + 2 to take greater advantage of homeostatic expansion mechanisms. Patients were monitored for delayed hematopoietic recovery because of this switch to early ex-T and the fact that survivin and hTERT are also expressed in hematopoietic stem cells. At the time of submission, 16 adult and 30 pediatric patients have been enrolled on these trials of whom 11 and 21, respectively, are evaluable for post-transplant hematopoietic and T-cell recovery. On the myeloma trial, the mean # of T cells infused was 3.95 x 1010 with 96% viability and a CD4/CD8 ratio of 1.8:1. At day 14 post-transplant, the median CD4 count was 1951/mcl (range 651–7668) and the median CD8 count was 4117/mcl (range 1499–39,354). The median # days to achieve an absolute neutrophil count (ANC) > 500 was 12 (range 11–14) and the median # days to achieve a PLT count >20,000/mcl was 13 days (range 0–28). Similarly, in the pediatric cohort, median CD4 and CD8 counts at day 30 were 1500 and 2100/mcl, respectively, compared to 22 and 14 in a group of pts who did not receive d+2 ex-T, with no impact on engraftment. 1 adult and 3 pediatric pts also developed an “engraftment syndrome” characterized by GHVD-like features with or without fever. The adult pt with day 14 CD4 and CD8 counts of 2,724 and 11,571 cells/mcl had clinical and histologic features of (autologous) gut GVHD. 3 pediatric pts developed pruritic rashes clinically and pathologically indistiguishable from GVHD within 14 d of ex-T infusion, with fever seen in 1. In the adult and 1 pediatric pt, steroid treatment led to complete resolution of symptoms. These combined data sets demonstrate that robust CD4 and CD8 T cells counts can be achieved as early as day 14 post-SCT when adults or children receive ex-T at day +2 post-SCT without exogenous IL-2 or other cytokine support. It appears that a subset of patients develop a T cell “engraftment syndrome” similar to autologous GVHD. The mechanisms responsible for this rapid immune cell recovery are currently under investigation.


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