Identification of a Single MiHA Specificity That Induces Resistance to MHC-Matched Allogeneic HCT.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3216-3216
Author(s):  
Alwi M. Shatry ◽  
Robert B. Levy
Keyword(s):  
T Cells ◽  
T Cell ◽  
Donor Cell ◽  
Hematopoietic Cell ◽  
Cell Transplant ◽  
Hematopoietic Cell Transplant ◽  
Post Transplant ◽  
Single Donor ◽  
Donor Cells ◽  
Allogeneic Marrow

Abstract T cell populations specific for transplantation antigens have been detected in sensitized individuals following multiple blood transfusions, marrow transplants as well as in multiparous females. Resistance to allogeneic hematopoietic cell transplant (HCT) in such sensitized individuals is consistent with the presence of a host memory T cell (TM) population specific for donor cell antigens. We hypothesized that a single donor minor histocompatibility (MiHA) epitope could elicit antigen-specific CD8 TM capable of resisting MHC-matched allogeneic hematopoietic cell engraftment. To address this question, CD8 TM were generated against a single MiHA epitope to determine if such cells could mediate resistance after ablative TBI conditioning. B6 mice were sensitized 2X to the H60 immunodominant MiHA epitope utilizing bone marrow-derived dendritic cells pulsed with the H60 (LTFNYRNL) peptide. Three weeks following booster sensitization, CD8 T cells were detected by tetramer staining in peripheral blood samples. These T cells exhibited a phenotype characteristic of memory cells (CD44hi, Ly 6C+). B6 (H2b) mice containing CD8+ H60+ T cells were subsequently conditioned with 9.0 Gy TBI and transplanted with 5 × 106 BALB.B (H2b) BM-TCD. One week post-transplant, naive recipients of BALB.B (H60+) or B6-H60 congenic TCD-BM contained >10-fold higher levels of circulating donor cells than the B6 dendritic cell/peptide sensitized recipients. Donor progenitor cells were also found to be significantly reduced in sensitized recipients of allogeneic TCD-BM at this time. Two weeks post-HCT, recipients of syngeneic marrow exhibited >10-fold greater frequency of circulating donor cells compared to recipients of MHC-matched allogeneic marrow (< 5% donor chimerism was detected). These findings demonstrate that host T cells with specificity against a single donor MiHA determinant are sufficient to induce resistance to MHC-matched allogeneic marrow engraftment. Such observations regarding the effector response of HVG contrast those by donor T cell responses post-transplant in which single MiHA differences fail to induce GVHD. Finally, heterologous immunity to virus has been reported to generate allo-reactive TM cells. Since such TM repertoires could include specificity for MiHA immunodominant epitopes, the presence of TM populations that can mediate resistance in “naive” recipients may be more prevalent than hitherto appreciated.

scholarly journals Development of immunosuppressive myeloid cells to induce tolerance in solid organ and hematopoietic cell transplant recipients

2021 ◽  
Author(s):  
Kent P Jensen ◽  
David Hongo ◽  
Xuhuai Ji ◽  
Pingping Zheng ◽  
Rahul D Pawar ◽  
...  
Keyword(s):  
Clinical Trials ◽  
T Cells ◽  
Conditioning Regimen ◽  
Myeloid Cells ◽  
Hematopoietic Cell ◽  
Mixed Chimerism ◽  
Solid Organ ◽  
Cell Transplant ◽  
Hematopoietic Cell Transplant ◽  
Post Transplant

Replacement of failed organs followed by safe withdrawal of immunosuppressive drugs have long been the goals of organ transplantation. We studied changes in the balance of T and myeloid cells in blood of HLA-matched and -mismatched patients given living donor kidney transplants (KTx) followed by total lymphoid irradiation (TLI), anti-thymocyte globulin (ATG) conditioning, and donor hematopoietic cell transplant (HCT) to induce mixed chimerism and immune tolerance. The clinical trials were based on a conditioning regimen used to establish mixed chimerism and tolerance in mice. In pre-clinical murine studies, there was a profound depletion of T cells and an increase in immunosuppressive, polymorphonuclear (pmn), myeloid derived suppressor cells (MDSCs) in the spleen and blood following transplant. Selective depletion of the pmn-MDSCs in mice abrogated mixed chimerism and tolerance. In our clinical trials, patients given an analogous tolerance conditioning regimen developed similar changes including profound depletion of T cells and a marked increase in MDSCs in blood post-transplant. Post-transplant pmn-MDSCs transiently increased expression of lectin-type, oxidized LDL receptor-1 (LOX-1), a marker of immunosuppression, and production of the T cell inhibitor, arginase-1. These post-transplant pmn-MDSCs suppressed the activation, proliferation, and inflammatory cytokine secretion of autologous, TCR microbead-stimulated, pre-transplant T cells when co-cultured in vitro. In conclusion, we elucidated changes in receptors, and function of immunosuppressive myeloid cells in patients enrolled in the tolerance protocol that were nearly identical to the that of MDSCs required for tolerance in mice. The clinical trials are registered in Clinicaltrials.gov under NCT #s 00319657 and 01165762.

scholarly journals Adenovirus Viral Kinetics and Mortality in Ex Vivo T Cell-Depleted Hematopoietic Cell Transplant Recipients With Adenovirus Infection From a Single Center

2020 ◽  
Vol 222 (7) ◽  
pp. 1180-1187
Author(s):  
Yeon Joo Lee ◽  
Jiaqi Fang ◽  
Phaedon D Zavras ◽  
Susan E Prockop ◽  
Farid Boulad ◽  
...  
Keyword(s):  
T Cell ◽  
Ex Vivo ◽  
Area Under The Curve ◽  
Absolute Lymphocyte Count ◽  
Hematopoietic Cell ◽  
Cell Transplant ◽  
Hematopoietic Cell Transplant ◽  
Viral Kinetics ◽  
Cox Models ◽  
Viral Loads

Abstract Background We report on predictors of adenovirus (ADV) viremia and correlation of ADV viral kinetics with mortality in ex vivo T-cell depleted (TCD) hematopoietic cell transplant (HCT). Methods T cell-depleted HCT recipients from January 1, 2012 through September 30, 2018 were prospectively monitored for ADV in the plasma through Day (D) +100 posttransplant or for 16 weeks after the onset of ADV viremia. Adenovirus viremia was defined as ≥2 consecutive viral loads (VLs) ≥1000 copies/mL through D +100. Time-averaged area under the curve (AAUC) or peak ADV VL through 16 weeks after onset of ADV viremia were explored as predictors of mortality in Cox models. Results Of 586 patients (adult 81.7%), 51 (8.7%) developed ADV viremia by D +100. Age &lt;18 years, recipient cytomegalovirus seropositivity, absolute lymphocyte count &lt;300 cells/µL at D +30, and acute graft-versus-host disease were predictors of ADV viremia in multivariate models. Fifteen (29%) patients with ADV viremia died by D +180; 8 of 15 (53%) died from ADV. Peak ADV VL (hazard ratio [HR], 2.25; 95% confidence interval [CI], 1.52–3.33) and increasing AAUC (HR, 2.95; 95% CI, 1.83–4.75) correlated with mortality at D +180. Conclusions In TCD HCT, peak ADV VL and ADV AAUC correlated with mortality at D +180. Our data support the potential utility of ADV viral kinetics as endpoints in clinical trials of ADV therapies.

Donor DC Subsets Polarize Donor T-Cell Immune Responses in Allogeneic BMT.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 573-573
Author(s):  
Jian-Ming Li ◽  
Cynthia Giver ◽  
Doug McMillan ◽  
Wayne Harris ◽  
David L. Jaye ◽  
...  
Keyword(s):  
Stem Cells ◽  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Peripheral Blood ◽  
Immune Reconstitution ◽  
Hematopoietic Cell ◽  
Post Transplant ◽  
Donor T Cells ◽  
Ifn Γ

Abstract Introduction: Impaired or inappropriate immune reconstitution after allogeneic bone marrow transplantation (BMT) can lead to infection, graft-versus-host disease (GvHD) and leukemia relapse. We have previously reported that BM contains two populations of dendritic cell (DC) subsets, CD11b+ DC and CD11b− DC, and that CD11b depleted donor BM promoted increased donor T-cell chimerism and increased graft-versus-leukemia (GvL) activity in C57BL/6 → B10BR transplants [BBMT, 2004, 10: 540]. To explore the mechanism by which CD11b-depletion improved allo-reactivity, we performed allogeneic hematopoietic cell transplants using defined populations of donor stem cells, DCs, and T-cells in a MHC mis-matched BMT model. Methods: We transplanted FACS purified populations of 50,000 GFP+ CD11b- DC or CD11b+ DC in combination with 5,000 FACS purified Lin- Sca-1+ c-kit+ hematopoietic stem cells (HSC) and 300,000 or 1,000,000 congenic spleen T-cells from C57BL/6 donors into C57BL/6[H-2Kb], B10BR[H-2Kk] and PL/J[H-2Ku] recipients. Proliferation of CFSE stained donor T-cells was measured at 72 hours post-transplant. FACS cytometric bead array and intracellular cytokine staining measured serum and intracellular cytokines in donor T-cells. Results: The initial proliferation and Ki-67 expression of CFSE labeled donor T-cells in allogeneic recipients were much higher than in syngeneic recipients (homeostatic proliferation). Confocal microscopy showed co-localization of donor DC subsets with donor T-cells in the recipient spleens at 3 and 10 days post-transplant. In the allogeneic transplant settings, donor T-cells co-transplanted with CD11b- DC showed increased IFN-γ synthesis at 3 and 10 days post-transplant compared to donor T-cells co-transplanted with HSC plus CD11b+ DC or HSC alone. Increased proliferation of donor T-cells led to increased donor T-cell chimerism at day 10, 30, 60, and day105 post-transplant among recipients of CD11b- DC compared to recipients of HSC alone or HSC plus CD11b+ DC (Figure 1). Transplantation of spleen T-cells and CD11b- DC did not increase GvHD, but was associated with full donor chimerism. In contrast, transplantation of allogeneic CD11b+ DC led to persistence and expansion of residual host T-cells (Figure 2), increased numbers of donor CD4+CD25++Foxp3+ T-cells, and higher serum level of IL-10 supporting early post-transplant expansion of donor T regulatory cells (Treg). Conclusions: Donor CD11b- DC promoted immune reconstitution by polarizing donor T-cells to Th1 immune responses associated with increased IFN-γ synthesis and donor T-cell proliferation, while donor CD11b+ DC suppressed immune reconstitution by inhibiting donor T-cell allogeneic immune responses. These data support a novel paradigm for the regulation of post-transplant immunity and suggest clinical methods to test the hypothesis that manipulation of the DC content of a hematopoietic cell allograft regulates post transplant immunity in the clinical setting. Figure 1. Donor Spleen Derived T-cells in Peripheral Blood [* p<0.05, v.s. recipients of HSC plus CD11b(+)DC and spleen T-cells] Figure 1. Donor Spleen Derived T-cells in Peripheral Blood [* p<0.05, v.s. recipients of HSC plus CD11b(+)DC and spleen T-cells] Figure 2. Host Derived T-cells in Peripheral Blood [* p<0.05, v.s. recipients of HSC plus CD11b(-)DC and spleen T-cells] Figure 2. Host Derived T-cells in Peripheral Blood [* p<0.05, v.s. recipients of HSC plus CD11b(-)DC and spleen T-cells]

Donor T Cells from B Cell Deficient Mice Inhibit B Cell Development in Normal Recipients after Hematopoietic Cell Transplantation.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3265-3265
Author(s):  
Antonia M.S. Mueller ◽  
Jessica A. Allen ◽  
David Miklos ◽  
Judith A. Shizuru
Keyword(s):  
T Cells ◽  
B Cell ◽  
Hematopoietic Cell Transplantation ◽  
Hematopoietic Cell ◽  
Cell Transplant ◽  
Hematopoietic Cell Transplant ◽  
Hematopoietic Stem ◽  
Donor Chimerism ◽  
Donor T Cells ◽  
The Impact

Abstract Allogeneic hematopoietic cell transplant (HCT) recipients often exhibit B cell (BC) lymphopenia due, in part, to graft-versus-host-disease (GVHD). Here, we studied the impact of donor T cells (TC) on BC deficiency post minor antigen-mismatched HCT. Following lethal irradiation, BALB.B mice were given FACS purified hematopoietic stem cells (HSC: cKIT+Thy1.1loLin-Sca-1+) alone, with whole splenocytes (SP), CD4 or CD8 TC from minor antigen-mismatched C57BL/6 (B6) mice. Chimerism analyses were performed on day (d) 30, 60, and 90. When pure HSC were transplanted, BCs reconstituted promptly (median 33% of lymphocytes [d30]; 61% [d60]; 74% [d90]), whereas TC engraftment was retarded and did not achieve full donor chimerism. Addition of SP or CD4 TCs, or to a lesser degree CD8 TCs, delayed BC reconstitution, with extremely low percentages of BCs beyond d60. This BC suppression correlated with the degree of acute GVHD, and BC numbers increased with recovery from GVHD. Additionally, this BC suppression was in stark contrast to TC development, with TC transfer resulting in early conversion to full donor chimerism. To test if previous events in the donor sensitize TCs against BC features (e.g. minor antigens), thereby promoting anti-BC cytotoxicity post-HCT, TCs from B6 muMT mice were co-transplanted with HSC. muMT mice are devoid of mature BCs because they lack the mu chain; consequently, their TCs were not exposed to BCs prior to transfer. Remarkably, BC engraftment was completely prevented through d90. TCs regenerated faster, but the vast majority originated from spleen and not HSC. To differentiate this lack of BC engraftment from GVHD-associated, alloreactive BC lymphopenia, syngenic B6 recipients were used. Again, initially complete blockade of BC engraftment was observed, although this suppression was overcome earlier post-HCT as compared to the minor-mismatched pair (median % BC d60: ’HSC only’ recipients 52%; +CD4 17%; +CD8 48%). To clarify if this phenomenon was a purely cytotoxic reaction of muMT TC against BCs, we used WT B6 HSC +/− SP as donors and lethally or sublethally irradiated muMT mice as recipients. All groups, including sublethally irradiated animals, where host muMT TC were still present, engrafted BCs making a direct anti-BC cytotoxicity unlikely as the sole cause of the BC inhibition. FACS analysis of bone marrow was used to assess the developmental stages of BCs (Hardy fractions (Fr.) A-F) and revealed GVHD recipients with peripheral B lymphopenia have a shift of B220+ cells from more mature Fr. D-F to immature Fr. A-C stages and a lower proportion of IgM expressing BC. Recipients of the muMT TCs showed, in addition to a shift to more immature stages, a clear block in BC development with an absent switch to the expression of IgM (stage D to E)(Fig. 1). In conclusion, muMT TCs are capable of blocking BC maturation when transferred into WT mice, suggesting defective TC activity in muMT animals necessary for the co-development of both BCs and TCs. Furthermore, this study provides evidence that mature TCs are capable of interfering with BC regeneration post-HCT. Hence, our HCT combinations using WT and muMT B6 mice provide a powerful tool to study the role of TC function in the process of donor BC development post-HCT.

scholarly journals Non-Genetic Determinants of Clonotypic T Cell Expansion Following Allogeneic Stem Cell Transplant

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 646-646
Author(s):  
Albert Yeh ◽  
Motoko Koyama ◽  
Simone A Minnie ◽  
Julie Boiko ◽  
Kathleen S Ensbey ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Copy Number ◽  
Research Funding ◽  
Molecular Transport ◽  
Cell Transplant ◽  
Antigen Specificity ◽  
Donor Pool ◽  
Post Transplant ◽  
Low Copy Number

Abstract Background: The immunologic basis of acute GVHD fundamentally involves alloreactive donor T cells that recognize foreign major histocompatibility complex (MHC)-peptide structures derived from both major and minor antigen mismatches with the host. Within this paradigm, the relationship between the donor and recipient genetics represents a closed system that dictates the potential ability of any given T cell receptor (TCR) to expand, raising the question of whether there are predictable aspects of TCR reconstitution at a clonal level. Take a hypothetical example - if genetically identical twins were to receive allogeneic grafts from the same donor and both recipients develop GVHD, would one expect similar TCRs to be clonally expanded? It has been challenging to rigorously explore this phenomenon, however, because of the vast combinatorial diversity of αβ TCRs, the high prevalence of low copy number TCRs, and sampling constraints - all of which render tracking and comparing TCR expansion between the donor and host difficult. Methods: We address these challenges in order to better understand the predictability TCR clonal dynamics through an analysis platform utilizing 1) a series of matched and mismatched murine transplant experiments where genetically identical littermates receive T cells from the same polyclonal donor pool, thus creating multiple transplant replicates simulating the twin transplant system describe above (Fig 1), and 2) probabilistic modeling of individual TCR frequencies to account for partitioning stochasticity (variation in how low copy number TCRs are distributed from donor to recipient). We conduct high-throughput DNA-based TCR amplicon sequencing for both donor and post-transplant recipient samples to generate over 20 million TCRs and model the expansion rates of all identifiable TCRs in each transplant system using a Bayesian approach. Results: While overall V and J gene usage were similar amongst identical recipients (Fig 2), we find that a small fraction of TCR clonotypes appears to have widely disparate clone counts amongst identical recipients receiving the same donor T cell pool. For example, we saw 9,739, 129 and 0 copies of a particular TCR in 3 different recipients in our B6-&gt;B6D2F1 system (Fig 3). In order to distinguish whether TCR count discrepancies seen across identical recipients is simply a reflection of donor partitioning stochasticity or true differential expansion (Fig 4), we apply a Bayesian algorithm to identify differential expanders, which represent TCRs that are asymmetrically expanded between recipients of a genetically identical pair (Fig 5). These TCRs can be generated from both memory and naïve T cell compartments. The presence of these differentially expanded clones amongst identical recipients suggests that non-genetic dependent mechanisms may influence which TCRs expand post-transplant. We next show that broad gut decontamination of microbiota with peri-transplant vancomycin, gentamicin, cefoxitin and metronidazole dramatically reduced the fraction of differential expanders (p&lt;0.0001). However, the change in inflammation from microbiome depletion did not appear to drive this difference, as 1) MyD88/TRIF double knockout recipients (deficient TLR signaling) did not show a reduction in differential expanders, and 2) altering conditioning intensity (900cGy to 1300 cGy TBI) also did not change the fraction of differential expanders. Rather, the difference is likely antigenically driven, as differential expanders are enriched in antigen specificity compared to other TCR sequences (p&lt;0.0001) based on published algorithm that identify TCRs with similar amino acid sequence overlap. Conclusions: These results refine our current understanding of clonal T cell selection and expansion after allogeneic BMT and suggests that for a given transplant system, individual TCR selection is not solely dictated by genetic donor and recipient major and/or minor histocompatibility disparities. Rather, microbiota-derived molecules appear to behave as minor antigens to direct systemic clonal TCR selection. These data suggest a novel mechanism by which the microbiome may modulate transplant outcome, challenging current paradigms suggesting the microbiota primarily drive inflammation via their PAMP activities. Figure 1 Figure 1. Disclosures Hill: Applied Molecular Transport: Research Funding; Syndax Pharmaceuticals: Research Funding; Compass Therapeutics: Research Funding; NapaJun Pharma: Consultancy; Generon corporation: Consultancy; iTeos Therapeutics: Consultancy, Research Funding; Neoleukin Therapeutics: Consultancy; Roche: Research Funding.

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