Favorable Immune Reconstitution Profile after Allogeneic Hematopoietic Stem Cell Transplantation with Post-Transplant Cyclophosphamide

Abstract Background: The administration of post-transplant high-dose cyclophosphamide (PTCy) has been shown to be an effective strategy for GvHD prophylaxis following allogeneic peripheral blood stem cell transplantation(PBSCT) from alternative donors. PTCy is toxic to allogeneic activated proliferating T lymphocytes, such as effector T cells. Conversely, it may not materially affect memory T cells. Methods: We evaluated immune reconstitution profile and transplant outcome in patients who received PBSCT with and without PTCy. PTCy was given on day +3 and +4 following haploidentical transplant (HAPLO), or only on day +3 following HLA-matched unrelated donor (MUD) transplant. No PTCy was given to patients with HLA-matched related donors (MRD). All patients received GvHD prophylaxis as tacrolimus (day +5 to +180) and MMF (day +5 to +35). Preparative regimens were myeloablative regimens (fludarabine/busulfan, fludarabine/TBI 12 Gy, or CY/TBI 12) in all patients except 4 patients (received fludarabine/melphalan). Immune reconstitution profile (IRP) was tested via serial flow cytometry analysis of peripheral blood lymphocytes after transplant were done on days +30, +100, and +180. Results: Data of 70 patients who underwent allogeneic PBSCT in our institution were analyzed in 3 groups; MRD (n=22), MUD (n=35), and HAPLO (n=13). The total cohort had 33 males (47%), and had median age of 52 years (range 20-70). All patients had hematological malignancy except one patient with HLH. The median duration of follow up was 6 months (range 1-17). The median day of neutrophil and platelet engraftment were 13, 12, 17 and 18, 15, 22 days for MRD, MUD and HAPLO groups respectively. The one-year overall survival of the whole group was 67% (95% confidence interval: 48-80) with no difference in OS among the 3 cohorts (log rank P value 0.4) (Figure 1). Lymphocyte and lymphocyte subset (T, B, NK) count recovery for MUD and HAPLO was significantly less (p<0.05) than MRD during the first month post-HSCT but these differences were statistically insignificant by day +60 and remained so through day +365. Recovery of both CD4+ and CD8+ naïve T cell (CD45RA+CD27+CD197+) population was generally slower for HAPLO patients during the first year and significantly less through day+ 180 for CD4+ T cells. As predicted, central memory (CD45RA-CD27+CD197+) CD4+ and CD8+ T cells remained proportionately equivalent at 40% and 28% respectively for all groups during the first year. The effector memory (CD45RA-CD27+CD197-) population was also proportionately consistent at 25% of total for both CD4+ and CD8+ subsets. Interestingly, the effector T cell population (CD45RA+CD27-CD197-) trended higher for all three recipient groups at each time point for both CD4+ and CD8+ populations increasing from 20% at one month to over 40% at one year. Conclusion: Post-PBSCT survival was not significantly different from alternative donor graft recipients and those that received MRD PBSCT. Lymphocyte recovery was impaired for the PTCy groups in the immediate post-PBSCT period but quickly recovered to that seen in MRD recipients. Figure 1 Figure 1. Disclosures Saad: Spectrum: Honoraria; American Porphyria foundation: Research Funding; Astellas: Research Funding; Alexion: Honoraria. Lamb:Incysus, Ltd: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Download Full-text

Immune Reconstitution and Immune Correlates of Clinical Outcome IN Acute LEUKEMIA PATIENTS Treated with Haploidentical STEM CELL TRANSPLANTATION.

Blood ◽

10.1182/blood.v114.22.46.46 ◽

2009 ◽

Vol 114 (22) ◽

pp. 46-46

Author(s):

Alessandra Forcina ◽

Maddalena Noviello ◽

Veronica Valtolina ◽

Attilio Bondanza ◽

Daniela Clerici ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Immune Reconstitution ◽

Patient Specific ◽

Haploidentical Stem Cell Transplantation ◽

Gvhd Prophylaxis ◽

Kinetics Of

Abstract Abstract 46 The broader application of haploidentical stem cell transplantation (haplo-HCT), is limited by the delayed immune reconstitution (IR) secondary to the procedures for GvHD prophylaxis. This ultimately results in a high-rate of infectious complications and non-relapse mortality. We dynamically analyzed immunoreconstitution (IR) in patients undergoing haplo-HCT for acute leukemias enrolled in two different phase I-II clinical trials aimed at improving IR. In the first trial (TK007), 28 patients (out of 50 enrolled) received suicide-gene transduced donor T cells at day +42 after a T-cell depleted graft, in the absence of post-transplant immunosuppression. In the second trial (TrRaMM), 40 patients received an unmanipulated graft and a rapamycin-based GvHD prophylaxis. T-cell immune reconstitution was more rapid in TrRaMM than in TK007 patients, with a threshold of CD3 cells>100/μl reached at days +30 and +90, respectively. In both trials IR was mainly composed of Th1/Tc1 lymphocytes with an inverted CD4/CD8 ratio. While in TrRaMM patients we observed an early expansion of naïve and central memory T cells, producing high amounts of IL-2, in TK patients IR was mainly composed of activated effectors. Furthermore, in TrRaMM patients we detected high levels of CD4+CD25+CD127- T regulatory cells (up to 15% of circulating T lymphocytes) that persisted after rapamycin withdrawal, and was significantly superior to that observed in TK patients and in healthy controls. Interestingly, in contrast to the different kinetics of T-cell reconstitution, no differences were observed in time required to gain protective levels of CMV-specific T cells, as shown by ψIFN ELISPOT analysis. Protective frequencies of CMV-specific lymphocytes were observed 3 months after HCT in both groups, a time-point that in TrRaMM patients corresponds to the average time of rapamycin withdrawal. In both trials the number of circulating CMV-specific T cells was inversely correlated to the number and severity of subsequent CMV reactivations and days of antiviral therapy. GvHD was diagnosed in 16 TrRaMM patients (40%) and in 10 TK patients (35% of patients who received TK cells). Severity of GvHD was different in the two cohort of patients with 5 TrRaMM patients (12,5%) and only 2 TK patients (7%) with grade III-IV GvHD. Of interest, in the TrRaMM group CMV-specific immunity was significantly hampered by the immunosuppressive treatment required to treat GvHD. On the contrary, in the TK group, the administration of ganciclovir was able to activate the suicide machinery and control GvHD without impairing viral-specific T-cell immunocompetence. These results matched with the kinetics of CMV reactivations. We observed that while in TrRaMM patients 80% of viral reactivations occurred after the immunosuppressive therapy, in TK patients no significant differences could be assessed before and after therapy. IFN-ψ ELISPOT might thus be a relevant and predictive test to guide patient-specific clinical monitoring and antiviral treatment. Overall, these results show that early immune reconstitution can be promoted in haplo-HCT by different strategies associated with a wide range of alloreactive potential. The risks and benefits associated with alloreactivity should guide the therapeutic choice tuned on patient disease status and co-morbidities. Disclosures: Bordignon: Molmed Spa: Employment.

Download Full-text

New Developments in Allotransplant Immunology

Hematology ◽

10.1182/asheducation-2003.1.350 ◽

2003 ◽

Vol 2003 (1) ◽

pp. 350-371 ◽

Cited By ~ 39

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.

Download Full-text

The Elevated Ratio of Peripheral Blood CD27−CD4+ T Cells in Patients Received Allogeneic Stem Cell Transplantation Implies Altered T Cell Homeostasis.

Blood ◽

10.1182/blood.v106.11.1413.1413 ◽

2005 ◽

Vol 106 (11) ◽

pp. 1413-1413

Author(s):

Akiko Fukunaga ◽

Takayuki Ishikawa ◽

Takero Shindo ◽

Sumiko Takao ◽

Toshiyuki Hori ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

Cd4 T Cells ◽

Immune Reconstitution ◽

Cd4 T Cell ◽

T Cell Homeostasis ◽

Cell Homeostasis ◽

Effector Cells

Abstract One of the major problems following allogeneic stem cell transplantation (allo-SCT) is the inability to reconstitute an adequate immune system for an extended period. T-cell reconstitution is also delayed for years, especially in CD4+ T cells. In addition to impaired thymic function, shortened Naive T cell survival due to altered T cell homeostasis is reported to be responsible for delayed immune reconstitution. To further investigate the mechanisms of delayed immune recovery after allo-SCT, we focused on the frequencies of effector CD4+ T cells, because according to the previous reports, progressive linear differentiation model of CD4+ T cell predicts the accumulation of terminally differentiated effector cells when transition from naïve to memory T cells and memory to effector cells are accelerated. By flowcytometric analyses we confirmed that CD27−CD4+ T cells from allo-SCT recipients uniformly express CD95, with negative expression of CCR7 and CD62L. They also produce g-interferon (IFNg) in response to the immobilized anti-CD3 and soluble anti-CD28 stimulation, which is consistent with previous reports insisting that CD27−CD4+ T cells are functionally differentiated effector T cells. Measuring the ratio of CD27−CD4+ T cells among CD4+ T cells revealed that, although healthy donors and patients received allo-SCT within a year had comparable CD27+CD4+T-cell rate (90% vs. 83%, P=0.4436), significantly decreased rate was observed in patients transplanted more than 1 year before (55% vs. 83%, P=0.0005). The ratio of CD27+CD4+ T cells kept low during the first 5 years after allo-SCT, and then it slowly begun to increase. In addition, in patients who received stem cell grafts more than 1 year before, the ratio of CD27+CD4+ T cells were significantly higher in patients transplanted from HLA-matched siblings than in those received unrelated grafts (69% vs. 42%, P=0.0002). Other factors, such as stem cell source (BM or PBSC), patient age, and the presence of chronic GVHD did not influence the ratio of CD27+CD4+ T cells. To further investigate the characteristics of CD27−CD4+ T cells in post-transplant periods, peripheral CD4+ T cells from patients who had received allo-SCT more than 1 year before as well as healthy volunteers were sorted into CD27− and CD27+ fractions, stained with CFSE, and stimulated with immobilized anti-CD3 and soluble anti-CD28 antibodies. CD27−CD4+ T cells proliferated more vigorously at 3 days after stimulation, though after another 2-day culture, there was no difference in cell divisions between both cell groups. In addition, CD27+ cells from transplanted patients lost their expression more frequently than those from volunteers, while none of the CD27− cells stored its expression. The fact of one-way transition from CD27+ to CD27− also supported that CD27−CD4+ T cells are terminally differentiated T cells. The finding that the frequencies of CD27−CD4+ T cells begin to elevate at 1 year after allo-SCT indicates that T cells infused with allograft do not easily lose the surface expression of CD27, while T cells derived from donor’s stem cells do. Considering the fact that ratio of CD27−CD4+ T cells is much higher in recipients of unrelated grafts, and it gradually begin to decrease at 5 years after allo-SCT, the increased ratio of CD27−CD4+ T cells may reflect altered T cell homeostasis. The serial monitoring of the ratio of CD27−CD4+ T cells after allo-SCT may be useful in evaluating immune reconstitution status.

Download Full-text

Immunologic potential of donor lymphocytes expressing a suicide gene for early immune reconstitution after hematopoietic T-cell–depleted stem cell transplantation

Blood ◽

10.1182/blood-2002-08-2351 ◽

2003 ◽

Vol 101 (4) ◽

pp. 1290-1298 ◽

Cited By ~ 101

Author(s):

Sarah Marktel ◽

Zulma Magnani ◽

Fabio Ciceri ◽

Sabrina Cazzaniga ◽

Stanley R. Riddell ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Immune Reconstitution ◽

Cell Manipulation ◽

Transduction Efficiency ◽

Donor Lymphocytes

We have previously shown that the infusion of donor lymphocytes expressing the herpes simplex virus thymidine kinase(HSV-tk) gene is an efficient tool for controlling graft-versus-host disease (GVHD) while preserving the graft-versus-leukemia (GVL) effect. In addition to the GVL effect, the administration of donor HSV-tk+ cells could have a clinical impact in promoting immune reconstitution after T-cell–depleted stem cell transplantation (SCT). To explore this hypothesis, we have investigated whether in vitro polyclonal activation, retroviral transduction, immunoselection, and expansion affect the immune competence of donor T cells. We have observed that, after appropriate in vitro manipulation, T cells specific for antigens relevant in the context of SCT are preserved in terms of frequency, expression of T-cell receptor, proliferation, cytokine secretion, and lytic activity. A reduction in the frequency of allospecific T-cell precursors is observed after prolonged T-cell culture, suggesting that cell manipulation protocols involving a short culture time and high transduction efficiency are needed. Finally, the long-term persistence of HSV-tk+ cells was observed in a patient treated in the GVL clinical trial, and a reversion of the phenotype of HSV-tk+ cells from CD45RO+ to CD45RA+ was documented more than 2 years after the infusion. Based on all this evidence, we propose a clinical study of preemptive infusions of donor HSV-tk+ T cells after SCT from haploidentical donors to provide early immune reconstitution against infection and potential immune protection against disease recurrence.

Download Full-text

Alterations of Peripheral Blood T Cell Subsets following Donor Lymphocyte Infusion in Patients after Allogeneic Stem Cell Transplantation

Hemato ◽

10.3390/hemato2040046 ◽

2021 ◽

Vol 2 (4) ◽

pp. 692-702

Author(s):

Ann-Kristin Schmaelter ◽

Johanna Waidhauser ◽

Dina Kaiser ◽

Tatjana Lenskaja ◽

Stefanie Gruetzner ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Allogeneic Stem Cell Transplantation ◽

Peripheral Blood ◽

Donor Lymphocyte Infusion ◽

T Cell Subsets ◽

Mixed Chimerism

Donor lymphocyte infusion (DLI) after allogeneic stem cell transplantation (alloSCT) is an established method to enhance the Graft-versus-Leukemia (GvL) effect. However, alterations of cellular subsets in the peripheral blood of DLI recipients have not been studied. We investigated the changes in lymphocyte subpopulations in 16 patients receiving DLI after successful alloSCT. Up to three DLIs were applied in escalating doses, prophylactically for relapse prevention in high-risk disease (n = 5), preemptively for mixed chimerism and/or a molecular relapse/persistence (n = 8), or as part of treatment for hematological relapse (n = 3). We used immunophenotyping to measure the absolute numbers of CD4+, CD8+, NK, and CD56+ T cells and their respective subsets in patients’ peripheral blood one day before DLI (d-1) and compared the results at day + 1 and + 7 post DLI to the values before DLI. After the administration of 1 × 106 CD3+ cells/kg body weight, we observed an overall increase in the CD8+ and CD56+ T cell counts. We determined significant changes between day − 1 compared to day + 1 and day + 7 in memory and activated CD8+ subsets and CD56+ T cells. Applying a higher dose of DLI (5 × 106 CD3+ cells/kg) led to a significant increase in the overall counts and subsets of CD8+, CD4+, and NK cells. In conclusion, serial immune phenotyping in the peripheral blood of DLI recipients revealed significant changes in immune effector cells, in particular for various CD8+ T cell subtypes, indicating proliferation and differentiation.

Download Full-text

Differences in Immune Reconstitution and Cytokine Production in Children with Sibling Donor BMT Versus T-Cell Depleted PBSCT from Unrelated or Mismatched Family Donors.

Blood ◽

10.1182/blood.v108.11.2916.2916 ◽

2006 ◽

Vol 108 (11) ◽

pp. 2916-2916

Author(s):

Verena A. Wiegering ◽

Matthias Eyrich ◽

Paul G. Schlegel ◽

Beate Winkler

Keyword(s):

Bone Marrow ◽

T Cells ◽

Stem Cell ◽

T Cell ◽

Immune Reconstitution ◽

Haematopoietic Stem Cell ◽

First Year ◽

Th2 Cytokines ◽

Post Transplantation ◽

Cytokine Levels

Abstract Introduction: Transplantation of haematopoietic stem cell (HSCT) from human leucocyte antigen (HLA)-disparate parental donors presents an approach for the treatment of patients lacking an HLA-matched donor, but little is known about differences in immune reconstitution as compared to conventional BMT. We prospectively compared paediatric recipients of positively selected CD34+ peripheral blood stem cells from unrelated or HLA-mismatched donors vs. recipients of unmanipulated bone marrow from matched sibling donors. Patients: Immune reconstitution was studied in 20 children (20 transplants [5 sibling, vs. 8 UD, 7 haplo]; median age was 9,6 years; range 7m-26y; 7 female, 13 male). Blood samples were drawn before allo-HSCT, on days 14 (take), 30, 60, 100, 200 and 365 and >15months after SCT. Methods: We analyzed lymphocyte subpopulations using flow cytometry. Cytokines (IFNg, IL2, TNFa, IL4, IL5, IL10) were determined by FACS after in vitro stimulation with PMA, ionomycin and brefeldin for 24h. Additionally, we measured IL2, IL7, IL13, IL15, IFNg and TGFb in unstimulated sera by ELISA. Further more, we studied TREC values and did spectratype analysis by real time-PCR and gel electrophoresis. Results: After allo-HSCT, NK-cells were the cells, which regenerated first. In T-cells, decreased absolute counts could be detected as well as an inverted CD4-CD8-ratio during the first year after SCT. In CD4+ T-cells, the memory phenotype (CD45RO+) predominated. Sibling recipients show a faster T-cell regeneration than recipients of UD or mismatched family donors (MM). As to cytokine levels in unstimulated sera, IFNg levels remained stable, while we saw high level of IL4 shortly after allo-HSCT; IL4 levels decreased during the first year after SCT. TGFb showed increased levels post-transplantation for up to two years. In stimulated T-cells, we measured a rise in Th2-cytokines (IL4, IL5, IL10) until d60 and a decrease of IFNg/TNFa. Th2-cytokines returned to pre-transplantation levels until d200, whereas Th1-cytokines rise to higher level than before transplantation. We could find that IL2 was produced predominantly by CD4+ / IFNg+ cells and by CD8+cells. Patients who received T-cell depleted stem cell preparations show lower IFNg and TNFa values and higher Th2-cytokine levels than patients who received bone marrow. TREC counts appear earlier in sib HSCT (median d60) than in MM-transplant (median d200). As to spectratype values, we found a distribution of the 24Vb gene families of 4,18% per Vb-family with clonal expansion, especially in the first months after HSCT, of BV6b>BV23>BV1>BV16.

Download Full-text

Long-Term T Cell Immune Reconstitution in Patients Surviving 10 or More Years after Allogeneic Stem Cell Transplantation for Hematologic Malignancies

Blood ◽

10.1182/blood.v112.11.1173.1173 ◽

2008 ◽

Vol 112 (11) ◽

pp. 1173-1173

Author(s):

Quan Le ◽

J. Joseph Melenhorst ◽

Bipin N. Savani ◽

Brenna Hill ◽

Sarfraz Memon ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

T Cell Receptor ◽

Allogeneic Stem Cell Transplantation ◽

Immune Reconstitution ◽

Cell Receptor ◽

Myelogenous Leukemia

Abstract After allogeneic stem cell transplantation (SCT), there is a prolonged immune deficiency and delayed T cell reconstitutions results in significant morbidity and mortality. However limited data are available on immune reconstitution in patients surviving beyond a decade following SCT. Four hundred sixty two patients with hematological malignancies received SCT from an HLA identical sibling in our institute between 1993–2004. Of these, 110 patients 3 or more years post-transplantation, prospectively enrolled in a long-term evaluation protocol. Twenty one of these survived more than 10 years post SCT (median follow-up 11.8 y range 10–14.75y). Diagnoses included chronic myelogenous leukemia (17), acute myelogenous leukemia and myelodysplastic syndrome (3), and multiple myeloma (1). We studied T cell reconstitution in these patients and compared it to samples from their stem cell donors cryopreserved at time of transplant. There was no difference of age at SCT in patients (median age 35.5, range 13–56y) and in the donors (median age 34, range 14–58y). All patients received cyclophosphamide and 13.6 Gy total body irradiation. Patients received T cell depleted bone marrow (n=15) or peripheral blood SCT (n=6) with cyclosporine GVHD prophylaxis and delayed add-back of donor lymphocytes 30–90 days post transplant. Six (29%) developed acute GVHD (grade II–IV) and 18 (86%) chronic GVHD (13 limited, 5 extensive). Six (29%) patients received immunosuppressive therapy (IST) for cGVHD beyond 3 years from SCT but all were off immunosuppressive treatment at the time of study. In the 21 patients there were no significant difference in the absolute lymphocyte, neutrophil or monocyte count, compared with the donor pre-transplant absolute counts of circulating NK and T cell subsets, and B cells were measured using multicolor flow cytometric analysis in 9 patient-donor pairs. Patients had fewer naïve CD4 (p = 0.049) and naïve CD8 (p = 0.004) T cells, fewer CD4 central memory T cells (p = 0.03), fewer CD56 [int] CD16-NKG2A+2D+ NK cells (p = 0.02); and more effector CD8+ T cells (p = 0.04) in patients compared to their donors. ALC and FoxP3+ regulatory T cells were not significantly different between the patients and their donors. The T cell receptor excision circles (TRECs) and T cell receptor repertoire analyses to evaluate thymic function and T cell regeneration is ongoing. In conclusion, patients surviving 10 or more years after allogeneic SCT still show a deficit in the naïve and central memory post-thymic compartment. However these abnormalities appear to be compatible with good health. Figure Figure

Download Full-text

Disease-Specific Recovery of Regulatory T Cell After Allogenic Stem Cell Transplantation

Blood ◽

10.1182/blood.v116.21.4689.4689 ◽

2010 ◽

Vol 116 (21) ◽

pp. 4689-4689

Author(s):

Thomas St\)big ◽

Michael Lioznov ◽

Ulrike Fritsche-Friedland ◽

Haefaa Alchalby ◽

Christine Wolschke ◽

...

Keyword(s):

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

Treg Cell ◽

Regulatory T Cell ◽

Immune Reconstitution ◽

Treg Cells ◽

Cell Number ◽

Allogenic Stem Cell Transplantation ◽

One Year

Abstract Abstract 4689 Introduction: Allogenic stem cell transplantation (allo SCT) offers a potential curative approach for many malignant and non malignant haematological diseases. Despite its therapeutic benefit, long term immunodeficiency, poor immune reconstitution and Graft vs. Host Disease (GvHD) can often be limiting drawbacks. Since the nineties, regulatory T cell subsets (Treg) have been described and several lines of evidence indicated their implication on GvHD occurrence and progression. We analysed the immune reconstitution of 184 patients who underwent allo SCT at our Transplant Center from 2007 till 2009. Patients, Materials and Methods: Differential lymphocyte subsets were analysed by flow cytometry. Antigens were stained by usage of the following mAb: CD3, CD4, CD8, CD19, HLA-DR, CD56/CD16, CD45RA, CD45RO, CD45, γδ TCR, CD25, and CD127. Tregs were evaluated on simultaneous expression of CD4/CD25hi/CD127low. Data were obtained in monthly intervals for the first six months and thereafter every six months for the next 3 years. Data were analysed for three different subgroups: Multiple Myeloma (MM: n=83), Myelofibrosis (PMF: n=22) and AML/MDS (n=51). Smaller number subgroups of patients with CML (n=11), NHL (n=10) and ALL (n=7) were included into the overall analysis but not evaluated separately. Results: The mean value of Treg cell number before allo SCT was 2,5% of the total leukocyte number in all patients. There was no significant difference in the Treg level in any of the three major groups (MM: 2,2%; PMF: 2,1% and AML/MDS: 2,03%). All patients exhibited a significant reduced number of Treg cells during the first 30 days after allo SCT (MM: 0,79%; p= 0,009; PMF: 0,41%; p= 0,01; MDS/AML: 0,6%; p=0,01). Between day 30 and 60 after allo SCT patients with MM had a transient Treg recovery to baseline level (2,4%) while Tregs of patients with PMF or MDS/AML remained significantly lower in comparison to baseline value (PMF: 0,72%, p=0,002 and MDS/AML 0,81%, p=0,01 respectively). One year after allo SCT a faster Treg recovery (1,3% and 1,8% respectively) was observed in MM and MDS/AML patients while patients with PMF still maintained a significant reduction (0,65%; p=0,01). Interestingly, in the second year after allo SCT, Treg cell levels were decreased in all investigated subgroups (MM: 1,1%, p=0,008; PMF: 0,7%, p=0,02 and MDS/AML: 0,7%, p<0,0001), while after 3 years Treg cell number achieved pretransplant level. In contrast to Treg cells, total T cells are only transiently but significantly reduced within the first 180 days. Conclusion: A highly dynamic Treg cell recovery after allo SCT was observed in our group of patients. Even one year after allo SCT Treg reconstitution is still ongoing. Our data highlight that there is a distinctive difference in Treg recovery among the various fore mentioned diseases. Treg reconstitution appeared to be prolonged in patients with PMF in comparison to the other subgroups. Our data provide a basis for further analysis towards differential Treg reconstitution and its potential impact on allo SCT complications. Disclosures: No relevant conflicts of interest to declare.

Download Full-text

Monitoring Early CMV-Specific CD8+ T-Cell Responses After Allogeneic Stem Cell Transplantation By Pentamer and Streptamer Staining

Blood ◽

10.1182/blood.v122.21.4597.4597 ◽

2013 ◽

Vol 122 (21) ◽

pp. 4597-4597

Author(s):

Lorea Beloki ◽

Miriam Ciaurriz ◽

Natalia Ramirez ◽

Amaya Zabalza ◽

Cristina Mansilla ◽

...

Keyword(s):

T Cells ◽

Stem Cell ◽

T Cell ◽

Stem Cell Transplantation ◽

Antiviral Therapy ◽

Allogeneic Stem Cell Transplantation ◽

Immune Reconstitution ◽

Specific Ctls ◽

Cmv Reactivation

We present the results of a pilot study using pentamer (PM) and streptamer (ST) multimer complexes for monitoring CMV-specific CD8+ T-cells (CTLs). We analysed 15 patients that underwent allogeneic Stem Cell Transplantation (HSCT). Patient characteristics are summarized in Table 1. All patients and donors were positive for the HLA-A*02:01 allele. PM and ST were directed against the epitope NLVPMVATV (495-503) of the CMV phosphoprotein 65 (pp65). Samples were obtained at 15-day intervals until day +90 and monthly thereafter.PatientCMV status (D/R)GenderAgeDiagnosisDonorConditioningEngraftment (day)Follow up (months)GVHD (day)1+/+F43NHLSIBRIC2415-2-/+F33MDSURDRIC1912-3+/+M55AMLSIBMAC1714474-/+F41AMLURDMAC2121-5+/+F32AMLSIBMAC2013256+/+F64MDSSIBRIC2714897-/+M58CLLURDRIC2313928+/+M57ALLURDMAC155-9+/+F39AMLURDMAC2012-10-/+M42ALLURDMAC2125-11-/+M44AMLURDMAC12815312+/+F65AMLSIBRIC258-13-/+M27AMLSIBMAC3031814+/+M65AMLSIBRIC1966215+/-F30SAASIBRIC133- Three patterns were observed. In 3 patients (20%) no CMV-specific-CTLs could be detected despite several CMV reactivations, requiring prolonged cumulative antiviral therapy (median 68 days; range 67-136). In 7 patients (47%) CMV reactivation occurred at a mean of 41 days (10-94) and triggered a rapid increase of CMV-specific-CTLs with a median of 22.7 x 105/L (range 1.3-279.7). The CMV-PCR became immediately negative and antiviral therapy was stopped promptly after a median of 15.5 days (6-23). Finally, 5 patients (33%) showed an early immune reconstitution with CMV-specific-CTLs detected with a median of 0.7 x 105/L (range 0.2-2.8) in the absence of CMV-PCR reactivation at a median of 21 days (10-34) post-SCT. No CMV-PCR reactivation was observed in this group with a median follow-up of 12 months (5-14). Discussion Monitoring CMV-specific-T-cells might be able to distinguish patients at higher risk of recurrent virus reactivation and in need of prolonged antiviral therapy. Patients with increasing CMV-specific-CTLs detectable at the time of CMV-PCR reactivation may only need a short course of antiviral therapy, while those with early CMV-specific-CTLs may be protected from CMV reactivation. Conclusion Using Multimer-based (Pentamer and Streptamer) monitoring of CMV-specific T-cell immune reconstitution after allogeneic HSCT may contribute to the clinical decision regarding when and for how long to commence anti-CMV therapy. Disclosures: No relevant conflicts of interest to declare.

Download Full-text