The Graft-vs-Host Hematopoietic Effect Generated after Nonmyeloablative Allogeneic Stem Cell Transplantation (NST) Cures Patients with Severe PNH.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 811-811
Author(s):  
Yoshiyuki Takahashi ◽  
S. Chakrabarti ◽  
R. Srinivasan ◽  
T. Igarashi ◽  
A. Lundqvist ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
T Cell ◽  
Cell Transplantation ◽  
Conditioning Regimen ◽  
Cell Transplant ◽  
Hematopoietic Stem ◽  
Post Transplant ◽  
Donor T Cells

Abstract Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal disorder of hematopoietic stem cells characterized by RBC susceptibility to complement-mediated lysis. Infections related to neutropenia, bleeding associated with thrombocytopenia, and thrombosis all contribute to morbidity and mortality. Although allogeneic hematopoietic cell transplantation (HCT) can be curative, the high-risk of treatment-related mortality with myeloablative HCT precludes this approach for most patients with severe disease. We previously reported in vitro and in vivo data showing PNH cells could be killed by allo-reactive donor T-cells recognizing minor histocompatibility antigens expressed on both normal and GPI negative cells. Here we present updated data on a cohort of 11 patients with severe PNH who received a NST at the NHLBI from 5/99 through 6/2004. Eligibility included a diagnosis of PNH associated with one or more of the following :1) Transfusion dependence (n=9) 2) Prior thrombotic episodes (n=4) 3) Recurrent debilitating hemolytic crisis (n=7). Patients received a T-cell replete G-CSF mobilized blood stem cell transplant from an HLA-matched family donor following nonmyeloablative conditioning with cyclophosphamide (120mg/kg) and fludarabine (125mg/m2). Patients with a significant transfusion history had horse ATG (40mg/kg/day x 4) added to the conditioning regimen (n=9). CSA either alone (n=1) or combined with either MMF (n=4) or mini-dose methotrexate (n=6) was used as GVHD prophylaxis. The median % of GPI anchored protein negative neutrophils pre-transplant was 83% (range 13%–99%). Blood samples obtained post-transplant were analyzed by FACS to determine the percentage of persisting GPI negative neutrophils (CD15+/CD66b−/CD16−). Chimerism was also assessed post-transplant in T-cell and myeloid fractions by PCR assay of polymorphic short tandem repeats (STR). Neutrophil recovery occurred at a median 15 days (range 10–19). STR analysis revealed donor engraftment occurred in both myeloid and T-cell lineages in all patients. Self-limiting febrile hemolytic reactions associated with ATG administration (6/9 patients) and grade II-IV acute GVHD (n=5) were the most common complications associated with transplantation. With a median follow-up of 458 days (range 31–1917), all patients survive either in remission (n=8) or with declining GPI negative populations (n=3); GPI negative neutrophils were detected in all patients at engraftment but gradually declined until no longer detectable (<0.1%) in all 8 patients evaluable more than 100 days after transplantation, while 3 with shorter follow-up (days + 37, +51, +78) have persistent albeit rapidly declining PNH populations. The observation that GPI negative neutrophils populations decrease and ultimately disappear when myeloid chimerism transitions from mixed to full donor chimerism is consistent with PNH cells being eradicated through a graft-vs-host hematopoietic effect. None of the 7 patients with more than 1 year follow-up have had reoccurrence of their PNH clone. Conclusion: Alloreactive donor T-cells mediating graft-vs-host hematopoietic effects can immunologically eradicate PNH following NST. NST should be considered a viable and potentially curative option for patients with severe PNH.

Graft-Versus-Host Disease Targets Ovary and Causes Infertility After Allogeneic Hematopoietic Stem Cell Transplantation

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4470-4470
Author(s):  
Sonoko Shimoji ◽  
Koji Kato ◽  
Hidetsugu Tsujigiwa ◽  
Yoshihiro Eriguchi ◽  
Lifa Lee ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
Hematopoietic Stem Cell Transplantation ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Hematopoietic Stem Cell ◽  
Late Complication ◽  
Conditioning Regimen ◽  
Hematopoietic Stem ◽  
Donor T Cells

Introduction Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative therapy for various hematologic malignancies. Infertility associated with ovarian failure is a serious late complication for female survivors of allo-HSCT. While the role of pretransplant conditioning regimen has been well appreciated, it remains to be elucidated whether GVHD could be causally related to female infertility. We have addressed this issue in a mouse model of non-irradiated bone marrow transplantation (BMT) to avoid devastating effects of irradiation on the ovary. Method Female B6D2F1 (H-2b/d) mice (10 week old) were injected with 80 × 106 splenocytes from allogeneic B6 (H-2b) or syngeneic B6D2F1 donors on day 0. To track migration of donor T cells, CAG-EGFP B6 mice were utilized. Morphometric and immunohistochemical assessments were performed on ovarian sections harvested from recipients on day +21 to evaluate the integrity of ovarian architecture and inflammatory changes. To examine ovary functions, recipients were injected with pregnant mare’s serum gonadotropin (PMSG) on day +19 and human chorionic gonadotropin (hCG) on day +21 to induce ovulation and then oocytes were collected. To evaluate fertility of the recipients, recipients were mated with B6D2F1 males after BMT and mating was repeated 6 times until day +150, and newborns were enumerated. Result In this model, GVHD occurred early after BMT at a peak around day +21 particularly in the gut and liver. Histological examination of the ovaries from allogeneic recipients on day +21 demonstrated GFP+ donor T cells infiltrating in the layer of granulosa cells of mature follicles beyond the basement membrane, cleaved-caspase 3+ apoptotic granulose cells surrounded by lymphocytes (satellitosis), and the destruction of PAS+ basal membrane, whereas there was neither donor T cell infiltration nor pathological changes of the ovaries in syngeneic animals (p = 0.002, Table). Majority of T cells infiltrating in the ovary was CD8+ T cells. In experiments of forced ovulation, numbers of oocytes were significantly less in allogeneic animals than in syngeneic animals (p = 0.043, Table), indicating an impairment of ovary functions. When allogeneic recipients were mated to healthy male mice, numbers of both delivery and newborns per litter decreased, whereas syngeneic recipients remain to be fully fertile. As a result, total numbers of newborns delivered by day +150 after BMT were significantly less in allogeneic animals than in syngeneic animals (p< 0.001, Table). Administration of 10 mg/kg of prednisolone from day 0 to day +20 significantly reduced ovarian GVHD and restored numbers of oocytes in allogeneic animals to the levels of syngeneic animals. Conclusion Our results demonstrate for the first time that GVHD targets ovary and induces impairment of ovary functions and infertility; and therefore, control of GVHD as well as protection of the ovary from the conditioning is important to prevent female fertility after allo-HSCT. Disclosures: No relevant conflicts of interest to declare.

Case Report: Haploidentical Stem Cell Transplantation In a 78 Year-Old Patient

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 5468-5468
Author(s):  
Thiago Xavier Carneiro ◽  
André Domingues Pereira ◽  
Theodora Karnakis ◽  
Celso Arrais Rodrigues
Keyword(s):  
Stem Cell ◽  
T Cell ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Hematopoietic Stem Cell ◽  
Peripheral Blood ◽  
High Dose ◽  
Cell Transplant ◽  
Hematopoietic Stem ◽  
Post Transplant

Abstract An older chronologic age has been a consistent predictor of poor outcomes in hematopoietic stem cell transplantation (HSCT), mainly due to non-relapse mortality (NRM). Therefore, non-curative treatment strategies are commonly adopted for these patients. However, mortality and treatment toxicity has decreased as a result of improved supportive measures, such as reduced intensity conditioning regimens and optimized infection management. T-cell replete haploidentical HSCT emerged as a feasible alternative for leukemia patients without substantial differences in outcomes when compared to fully matched related donor. We report an old adult woman treated with haploidentical HSCT. A 78 year-old female patient presented with anemia, leukocytosis, thrombocytopenia and blasts in the peripheral blood. Diagnosis of acute myelogenous leukemia was established. Conventional cytogenetic demonstrated chromosome eight trisomy, and FISH was negative for other common MDS/AML cytogenetic abnormalities. FLT3-ITD and NPM1 mutations were negative. Her medical history was negative except for heavy smoking. Considering the patients advanced age, the first attending physician chose not to administer intensive treatment and started on decitabine 20 mg/m2 for 5 days. She was refractory to the first-line treatment with persistent cytopenias and blasts in the peripheral blood four weeks after treatment was started. Comprehensive geriatric assessment was performed. She was considered independent for Basic Activities of Daily Living (ADL score 6) and Instrumental Activities of Daily Living (IADL score 27), without cognitive impairment in mini-mental state examination (MMSE score 30), at risk of malnutrition in mini nutritional assessment (MNA 9). As she was considered fit, we decided to perform high-dose chemotherapy with idarubicin and cytarabine, but, once more, the disease was refractory. A rescue regimen was attempted with high-dose cytarabine and mitoxantrone, again, with no response. After discussing pros and cons with the patient and the family, we decided to start Another regimen consisting of topotecan and high dose cytarabine immediately followed by allogeneic hematopoietic stem cell transplantation (HSCT). At day 14, she had 3% blasts in the BM aspirate a T-cell replete haploidentical HSCT using her 52 year-old son as donor and mobilized peripheral blood as stem cell source was performed. Conditioning regimen consisted of fludarabine, cyclophosphamide, TBI 2Gy and post-transplant cyclophosphamide. Graft versus host disease (GVHD) prophylaxis consisted of mycophenolate mofetil and cyclosporine. She had neutrophil engraftment with complete donor chimerism at day+15 and platelet engraftment at day+17. At day+48, she had mild (stage II) skin acute GVHD resolved with topical steroids. Cyclosporine was withdrawn at day+ 93. Due to high relapse risk, the patient was started on monthly post-transplant azacitidine 36 mg/m2. At day+100 the patient remained in complete remission, complete donor chimerism in peripheral blood and bone marrow. Functionality was preserved (ADL score 6 and IADL score 24), presented discrete cognitive impairment (MMSE 28) and malnoutrition (MNA 5). She is now at day+182, doing well and performing again all usual daily activities. To the best of our knowledge, this is the oldest patient treated with haploidentical HSCT. Post transplant cyclophosphamide as T cell depletion strategy in haploidentical HSCT is well tolerated and widely available, being therefore an excellent alternative for patients without conventional donors who require immediate transplant. Older adults with hematologic malignancies are a heterogeneous group and decisions based on chronological age alone are clearly inappropriate. Recently, geriatric assessment proved to be an important prognostic tool in acute leukemia and may be useful in HSCT. In experienced centers, haploidentical HSCT in older adults may be a safe procedure and more accurate pre-transplantation risk stratification tools should be developed. Figure 1 Timeline of main events during hematopoietic stem cell transplant. Figure 1. Timeline of main events during hematopoietic stem cell transplant. Disclosures: No relevant conflicts of interest to declare.

scholarly journals NK Cell Reconstitution in Paediatric Leukemic Patients after T-Cell-Depleted HLA-Haploidentical Haematopoietic Stem Cell Transplantation Followed by the Reinfusion of iCasp9-Modified Donor T Cells

2019 ◽  
Vol 8 (11) ◽  
pp. 1904 ◽  
Author(s):  
Helena Stabile ◽  
Paolo Nisti ◽  
Cinzia Fionda ◽  
Daria Pagliara ◽  
Stefania Gaspari ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
T Cell ◽  
Stem Cell Transplantation ◽  
Nk Cells ◽  
Cell Transplantation ◽  
Nk Cell ◽  
Haematopoietic Stem Cell ◽  
Hematopoietic Stem ◽  
Donor T Cells

T-cell-depleted (TCD) human leukocyte antigen (HLA) haploidentical (haplo) hematopoietic stem cell transplantation (HSCT) (TCD-haplo-HSCT) has had a huge impact on the treatment of many haematological diseases. The adoptive transfer of a titrated number of T cells genetically modified with a gene suicide can improve immune reconstitution and represents an interesting strategy to enhance the success of haplo-HSCT. Natural killer (NK) cells are the first donor-derived lymphocyte population to reconstitute following transplantation, and play a pivotal role in mediating graft-versus-leukaemia (GvL). We recently described a CD56lowCD16low NK cell subset that mediates both cytotoxic activity and cytokine production. Given the multifunctional properties of this subset, we studied its functional recovery in a cohort of children given α/βT-cell-depleted haplo-HSCT followed by the infusion of a titrated number of iCasp-9-modified T cells (iCasp-9 HSCT). The data obtained indicate that multifunctional CD56lowCD16low NK cell frequency is similar to that of healthy donors (HD) at all time points analysed, showing enrichment in the bone marrow (BM). Interestingly, with regard to functional acquisition, we identified two groups of patients, namely those whose NK cells did (responder) or did not (non responder) degranulate or produce cytokines. Moreover, in patients analysed for both functions, we observed that the acquisition of degranulation capacity was not associated with the ability to produce interferon-gamma (IFN-γ Intriguingly, we found a higher BM and peripheral blood (PB) frequency of iCas9 donor T cells only in patients characterized by the ability of CD56lowCD16low NK cells to degranulate. Collectively, these findings suggest that donor iCasp9-T lymphocytes do not have a significant influence on NK cell reconstitution, even if they may positively affect the acquisition of target-induced degranulation of CD56lowCD16low NK cells in the T-cell-depleted haplo-HSC transplanted patients.

scholarly journals IMMUNITY TO INFECTIONS AFTER HAPLOIDENTICAL HEMATOPOIETIC STEM CELL TRANSPLANTATION

2016 ◽  
Vol 8 ◽  
pp. 2016057 ◽  
Author(s):  
Franco Aversa ◽  
Lucia Prezioso ◽  
Ilenia Manfra ◽  
Federica Galaverna ◽  
Angelica Spolzino ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Stem Cell ◽  
T Cell ◽  
Hematopoietic Stem Cell Transplantation ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Hematopoietic Stem Cell ◽  
Conditioning Regimen ◽  
Hematopoietic Stem ◽  
Post Transplant

The advantage of using a Human Leukocyte Antigen (HLA)-mismatched related donor is that almost every patient who does not have a HLA-identical donor or who urgently needs hematopoietic stem cell transplantation (HSCT) has at least one family member with whom shares one haplotype (haploidentical) and who is promptly available as a donor. The major challenge of haplo-HSCT is intense bi-directional alloreactivity leading to high incidences of graft rejection and graft-versus-host disease (GVHD). Advances in graft processing and in pharmacologic prophylaxis of GVHD have reduced these risks and have made haplo-HSCT a viable alternative for patients lacking a matched donor. Indeed, the haplo-HSCT  has spread to centers worldwide even though some centers have preferred an approach based on T cell depletion of G-CSF-mobilized peripheral blood progenitor cells (PBPCs), others have focused on new strategies for GvHD prevention, such as G-CSF priming of bone marrow and robust post-transplant immune suppression or post-transplant cyclophosphamide (PTCY). Today, the graft can be a megadose of T-cell depleted PBPCs or standard dose of unmanipulated bone marrow and/or PBPCs.  Although haplo-HSCT modalities are based mainly on high intensity conditioning regimens, recently introduced reduced intensity regimens (RIC)   showed promise in decreasing early transplant-related mortality (TRM), and extending the opportunity of HSCT to an elderly population with more comorbidities. Infections are still mostly responsible for toxicity and non-relapse mortality due to prolonged immunosuppression related, or not, to GVHD. Future challenges lie in determining the safest preparative conditioning regimen, minimizing GvHD and promoting rapid and more robust immune reconstitution.

scholarly journals T-cell suicide gene therapy prompts thymic renewal in adults after hematopoietic stem cell transplantation

Blood ◽  
2012 ◽  
Vol 120 (9) ◽  
pp. 1820-1830 ◽  
Author(s):  
Luca Vago ◽  
Giacomo Oliveira ◽  
Attilio Bondanza ◽  
Maddalena Noviello ◽  
Corrado Soldati ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
T Cell ◽  
Hematopoietic Stem Cell Transplantation ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Immune Reconstitution ◽  
Suicide Gene ◽  
Hematopoietic Stem ◽  
Donor T Cells

Abstract The genetic modification of T cells with a suicide gene grants a mechanism of control of adverse reactions, allowing safe infusion after partially incompatible hematopoietic stem cell transplantation (HSCT). In the TK007 clinical trial, 22 adults with hematologic malignancies experienced a rapid and sustained immune recovery after T cell–depleted HSCT and serial infusions of purified donor T cells expressing the HSV thymidine kinase suicide gene (TK+ cells). After a first wave of circulating TK+ cells, the majority of T cells supporting long-term immune reconstitution did not carry the suicide gene and displayed high numbers of naive lymphocytes, suggesting the thymus-dependent development of T cells, occurring only upon TK+-cell engraftment. Accordingly, after the infusions, we documented an increase in circulating TCR excision circles and CD31+ recent thymic emigrants and a substantial expansion of the active thymic tissue as shown by chest tomography scans. Interestingly, a peak in the serum level of IL-7 was observed after each infusion of TK+ cells, anticipating the appearance of newly generated T cells. The results of the present study show that the infusion of genetically modified donor T cells after HSCT can drive the recovery of thymic activity in adults, leading to immune reconstitution.

scholarly journals RNA-seq of human T cells after hematopoietic stem cell transplantation identifies Linc00402 as a regulator of T cell alloimmunity

2021 ◽  
Vol 13 (585) ◽  
pp. eaaz0316
Author(s):  
Daniel Peltier ◽  
Molly Radosevich ◽  
Visweswaran Ravikumar ◽  
Sethuramasundaram Pitchiaya ◽  
Thomas Decoville ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
T Cell ◽  
Hematopoietic Stem Cell Transplantation ◽  
Stem Cell Transplantation ◽  
Differential Expression ◽  
Cell Transplantation ◽  
Hematopoietic Stem ◽  
Human T Cells ◽  
Donor T Cells

Mechanisms governing allogeneic T cell responses after solid organ and allogeneic hematopoietic stem cell transplantation (HSCT) are incompletely understood. To identify lncRNAs that regulate human donor T cells after clinical HSCT, we performed RNA sequencing on T cells from healthy individuals and donor T cells from three different groups of HSCT recipients that differed in their degree of major histocompatibility complex (MHC) mismatch. We found that lncRNA differential expression was greatest in T cells after MHC-mismatched HSCT relative to T cells after either MHC-matched or autologous HSCT. Differential expression was validated in an independent patient cohort and in mixed lymphocyte reactions using ex vivo healthy human T cells. We identified Linc00402, an uncharacterized lncRNA, among the lncRNAs differentially expressed between the mismatched unrelated and matched unrelated donor T cells. We found that Linc00402 was conserved and exhibited an 88-fold increase in human T cells relative to all other samples in the FANTOM5 database. Linc00402 was also increased in donor T cells from patients who underwent allogeneic cardiac transplantation and in murine T cells. Linc00402 was reduced in patients who subsequently developed acute graft-versus-host disease. Linc00402 enhanced the activity of ERK1 and ERK2, increased FOS nuclear accumulation, and augmented expression of interleukin-2 and Egr-1 after T cell receptor engagement. Functionally, Linc00402 augmented the T cell proliferative response to an allogeneic stimulus but not to a nominal ovalbumin peptide antigen or polyclonal anti-CD3/CD28 stimulus. Thus, our studies identified Linc00402 as a regulator of allogeneic T cell function.

Haploidentical Transplantation In Adults ≥ 66 Years of Age

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3529-3529
Author(s):  
Dolores Grosso ◽  
Onder Alpdogan ◽  
Emmanuel C. Besa ◽  
Matthew Carabasi ◽  
Beth Colombe ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
T Cell ◽  
Older Patients ◽  
Karnofsky Performance Score ◽  
Cell Transplant ◽  
Hematopoietic Stem ◽  
Cell Dose ◽  
Co Morbidity ◽  
Donor T Cells

Abstract Abstract 3529 Hematologic malignancies in older patients are often characterized by resistant phenotypes which would ideally be treated by allogeneic hematopoietic stem cell transplant (HSCT). However, allogeneic HSCT in this age group is associated with greater regimen-related toxicity than in younger patients limiting its application. In addition, older patients have a smaller matched related donor pool due to the age and comorbidities of their siblings, but often have haploidentical offspring donor options. In order to extend the application of HSCT to older patients (>66), we developed a reduced intensity regimen utilizing haploidentical donors. In this approach, donor T cells and CD 34+ cells are infused at 2 separate times so that the dose and timing of each cell type can be independently controlled. This “break apart” method allows the tolerization of donor T cells by cyclophosphamide (CY) without exposure of the donor HSCs to the drug. Seventeen patients ages 66–77 with AML (9), advanced MDS (2), biphenotypic leukemia (1), CLL (2), NHL (2), and myelofibrosis (1) were treated. All but 2 patients had persistent disease at the time of HSCT. Ten of 17 had a Karnofsky Performance Score (KPS) of >90%, while 7 patients' KPS was 70–80%. The hematopoietic cell transplantation comorbidity index (HCT CI) for the group was between 0 and 5 points. Time from first treatment to HSCT was widely variable. The patients received fludarabine 30 mg/m2/d and cytarabine 2 Gms/m2/d on days -11 through -8. Thiotepa 5 mg/m2/d on days -11 to -9 was substituted for cytarabine in patients with active myeloid malignancies at HSCT. TBI (2 Gy) was given on d-6 immediately followed by 2 ×10e8/kg of the donor's T cells (DLI step). This T cell dose was associated with consistent engraftment and acceptable rates of GVHD in our prior studies. CY 60 mg/kg/d was given on days -3 and -2. A CD34 selected donor product was infused on day 0 (HSC step). T cells were collected from the donors prior to the start of G-CSF for stem cell mobilization. Mycophenolate Mofetil and Tacrolimus were started on d-1. All patients received the targeted T cell dose of 2×10e8 cells/kg, and within 24 hours developed fevers (median peak temperature 103.8f), and in many cases diarrhea and rash. All of the symptoms from this alloreaction resolved after the 2nd dose of CY. The median CD34+/kg dose was 3.34 × 10e6/kg (range 1.4–8.94 × 10e6/kg). The median amount of residual (non-tolerized) T cells in the HSC product was 0.24 × 10e4/kg (range 0.03–4.5 × 10e4/kg). One patient developed hypotension during the alloreaction requiring steroids. There were no other unexpected infusion-related reactions. Five patients developed decreases in ejection fraction (EF), not always associated with clinical heart failure, and 5 patients developed atrial dysrhythmias. Two early deaths occurred from sepsis and decreased EF on days +2 and +11, both in patients with KPS of 70–80% but with HCT-CI scores of <3 at the time of transplant. Fourteen of 17 (82%) patients were discharged to home and one (6%) to a skilled nursing facility. After discharge, one patient experienced a late rejection and died of toxicity from a second HSCT. Two patients died from severe GVHD (liver and gut) on days +161 and +90. The remaining patients had grade 0 to II GVHD controlled either with steroids or steroids plus photopheresis. One patient died from pneumonia on day +177. Four patients died from relapsed disease on days +55, +186, +198, and +510. Seven total patients (41%) are alive and without evidence of disease 1 to 30 months (median 19 months) after HSCT. All but 1 of these patients had a KPS of > 90% at transplant and all surviving patients had HCT CI scores of <3. Three of 3 patients with HCT CI scores >3 have died. The only 2 patients without active disease at HSCT are both alive, 19 and 26 months post HSCT. Except for the most recently treated patient who is not yet evaluable, all of these older patients have resumed their baseline activities of daily living. Haploidentical RIC using this 2 Step protocol is a viable treatment option for older adults. Rates of significant GVHD were acceptable and the majority of patients were able to tolerate the transplant procedures and be discharged to their homes. Based on the outcomes of this small group of patients, this type of therapy should be offered to fit senior adults with a low co-morbidity index especially if they have achieved a complete remission with up front therapy but are at high risk for relapse in the absence of HSCT. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Mouse Models of Antigen Presentation in Hematopoietic Stem Cell Transplantation

2021 ◽  
Vol 12 ◽  
Author(s):  
Motoko Koyama ◽  
Geoffrey R. Hill
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Mouse Models ◽  
Major Complication ◽  
Hematopoietic Stem ◽  
Curative Therapy ◽  
Donor T Cells ◽  
Immune Pathology

Allogeneic stem cell transplantation (alloSCT) is a curative therapy for hematopoietic malignancies. The therapeutic effect relies on donor T cells and NK cells to recognize and eliminate malignant cells, known as the graft-versus-leukemia (GVL) effect. However, off target immune pathology, known as graft-versus-host disease (GVHD) remains a major complication of alloSCT that limits the broad application of this therapy. The presentation of recipient-origin alloantigen to donor T cells is the primary process initiating GVHD and GVL. Therefore, the understanding of spatial and temporal characteristics of alloantigen presentation is pivotal to attempts to separate beneficial GVL effects from detrimental GVHD. In this review, we discuss mouse models and the tools therein, that permit the quantification of alloantigen presentation after alloSCT.

New Developments in Allotransplant Immunology

Hematology ◽  
2003 ◽  
Vol 2003 (1) ◽  
pp. 350-371 ◽  
Author(s):  
A. John Barrett ◽  
Katayoun Rezvani ◽  
Scott Solomon ◽  
Anne M. Dickinson ◽  
Xiao N. Wang ◽  
...  
Keyword(s):  
T Cells ◽  
Stem Cell ◽  
T Cell ◽  
Stem Cell Transplantation ◽  
Cell Transplantation ◽  
Immune Reconstitution ◽  
Cytokine Gene ◽  
Post Transplant ◽  
Cytokine Milieu ◽  
Cytokine Gene Polymorphisms

Abstract After allogeneic stem cell transplantation, the establishment of the donor’s immune system in an antigenically distinct recipient confers a therapeutic graft-versus-malignancy effect, but also causes graft-versus-host disease (GVHD) and protracted immune dysfunction. In the last decade, a molecular-level description of alloimmune interactions and the process of immune recovery leading to tolerance has emerged. Here, new developments in understanding alloresponses, genetic factors that modify them, and strategies to control immune reconstitution are described. In Section I, Dr. John Barrett and colleagues describe the cellular and molecular basis of the alloresponse and the mechanisms underlying the three major outcomes of engraftment, GVHD and the graft-versus-leukemia (GVL) effect. Increasing knowledge of leukemia-restricted antigens suggests ways to separate GVHD and GVL. Recent findings highlight a central role of hematopoietic-derived antigen-presenting cells in the initiation of GVHD and distinct properties of natural killer (NK) cell alloreactivity in engraftment and GVL that are of therapeutic importance. Finally, a detailed map of cellular immune recovery post-transplant is emerging which highlights the importance of post-thymic lymphocytes in determining outcome in the critical first few months following stem cell transplantation. Factors that modify immune reconstitution include immunosuppression, GVHD, the cytokine milieu and poorly-defined homeostatic mechanisms which encourage irregular T cell expansions driven by immunodominant T cell–antigen interactions. In Section II, Prof. Anne Dickinson and colleagues describe genetic polymorphisms outside the human leukocyte antigen (HLA) system that determine the nature of immune reconstitution after allogeneic stem cell transplantation (SCT) and thereby affect transplant outcomethrough GVHD, GVL, and transplant-related mortality. Polymorphisms in cytokine gene promotors and other less characterized genes affect the cytokine milieu of the recipient and the immune reactivity of the donor. Some cytokine gene polymorphisms are significantly associated with transplant outcome. Other non-HLA genes strongly affecting alloresponses code for minor histocompatibility antigens (mHA). Differences between donor and recipient mHA cause GVHD or GVL reactions or graft rejection. Both cytokine gene polymorphisms (CGP) and mHA differences resulting on donor-recipient incompatibilities can be jointly assessed in the skin explant assay as a functional way to select the most suitable donor or the best transplant approach for the recipient. In Section III, Dr. Nelson Chao describes non-pharmaceutical techniques to control immune reconstitution post-transplant. T cells stimulated by host alloantigens can be distinguished from resting T cells by the expression of a variety of activation markers (IL-2 receptor, FAS, CD69, CD71) and by an increased photosensitivity to rhodamine dyes. These differences form the basis for eliminating GVHD-reactive T cells in vitro while conserving GVL and anti-viral immunity. Other attempts to control immune reactions post-transplant include the insertion of suicide genes into the transplanted T cells for effective termination of GVHD reactions, the removal of CD62 ligand expressing cells, and the modulation of T cell reactivity by favoring Th2, Tc2 lymphocyte subset expansion. These technologies could eliminate GVHD while preserving T cell responses to leukemia and reactivating viruses.

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