scholarly journals Mixed T Cell Chimerism After Allogeneic Hematopoietic Stem Cell Transplantation for Severe Aplastic Anemia Using an Alemtuzumab-Containing Regimen Is Shaped by Persistence of Recipient CD8 T Cells

2017 ◽  
Vol 23 (2) ◽  
pp. 293-299 ◽  
Author(s):  
Francesco Grimaldi ◽  
Victoria Potter ◽  
Pilar Perez-Abellan ◽  
John P. Veluchamy ◽  
Muhammad Atif ◽  
...  
Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3283-3283
Author(s):  
Ga Hye Lee ◽  
Kyung Taek Hong ◽  
Jung Yoon Choi ◽  
Hee Young Shin ◽  
Won-Woo Lee ◽  
...  

Introduction: Pediatric and adolescent patients in need of allogeneic hematopoietic stem cell transplantation generally receive stem cells from older, unrelated or parental donors when a sibling donor is not available. Despite encouraging clinical outcomes, it has been suggested that immune reconstitution accompanied by increased replicative stress and a large difference between donor and recipient age may worsen immunosenescence in pediatric recipients. Therefore, in this study paired samples were collected at the same time from donors and recipients of haploidentical hematopoietic stem cell transplantation (HaploSCT). Methods: We conducted flow cytometry-based phenotypic and functional analyses and telomere length measurements of 21 paired T-cell sets from parental donors and children who received T cell-replete HaploSCT with post-transplant cyclophosphamide (PTCy) at Seoul National University Children's Hospital between February 2014 and January 2017. The conditioning regimen was comprised of targeted busulfan (total target area under the curve, 75,000 mg•h/L) with intensive pharmacokinetic monitoring, fludarabine and cyclophosphamide. Results: Fourteen pediatric, adolescent, and young adult patients with malignant disease and seven with nonmalignant disease were included with a median post-transplantation period of 16.9 months (range, 12.4-38.8). Senescent T cells, CD28- or CD57+ subsets of both CD4+ and CD8+ T cells, were significantly expanded in patients compared with parental donors. Further, not only CD4+CD28- T cells, but also CD4+CD28+ T cells showed reduced cytokine production capacity and impaired polyfunctionality compared with parental donors, whereas their TCR mediated proliferation capacity was comparable. Of note, the telomere length in patient T cells was preserved, or even slightly longer, in senescent T cells compared with donor cells. We also found that the patients had a higher level of γ-H2AX-expressing CD28- senescent T cells compared with the donors, which is used as a DNA damage marker. Regression analysis showed that senescent features of CD4+ and CD8+ T cells in patients were influenced by donor age and the frequency of CD28- cells, respectively. Conclusions: Our data suggest that T cells undergo premature immunosenescent changes and exhibit functional defects in pediatric HaploSCT recipients. Further, there is an increased level of DNA damage in patient CD4+ T cells compared to those of parental donors. Therefore, long-term, comprehensive immune monitoring of these patients is necessary. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4081-4081
Author(s):  
Tomas Kalina ◽  
Ladislav Krol ◽  
Jan Stuchly ◽  
Petra Keslova ◽  
Petr Hubacek ◽  
...  

Abstract Abstract 4081 Introduction: Depletion of cellular immunity as a consequence of conditioning before allogeneic hematopoietic stem cell transplantation (HSCT) frequently results in CMV reactivation, which may in turn lead to life-threatening infections and require timely antiviral treatment. Methods: We have investigated the ex vivo response of CMV-specific CD4+ and CD8+ T-cells to CMV antigen (combined CMV total lysate, pp65 and IE-1 peptide mix) in 191 samples from 118 individuals. We included patients with either high or undetectable viral loads, and those who controlled or did not control their CMV reactivations. All patient subsets were compared to healthy donors. Polychromatic flow cytometric measurements of CD154 (CD40L), intracellular cytokines (IFNγ, IL2), and a degranulation marker (CD107a) revealed the functional status of various T-cells simultaneously. Results: We found that dual IFNγ/IL2 producing CD8+ T-cells were significantly increased in patients controlling their CMV reactivations (average 0.33%, SD=0.4%) compared to non-controllers (average=0.02%, SD=0.07%). In contrast, CD8+ T-cells that produced IFNγ only were the most abundant subtype but they were present in a substantial number of both, controllers (average 4.36%, SD=4.8%) and non-controllers (average 1.64%, SD=3.7%). Hierarchical clustering of distinct functional signatures revealed that polyfunctional CD8+ T-cells were acting in concert with other subsets, whereas the isolated production of IFNγ by CD8+ T cells heralds insufficient collaboration with others. On a subset of patients with reactivation of CMV post HSCT, we have evaluated the sensitivity and specificity of functional signature test (n=64 samples) to predict reactivation control. When dual IFNγ/IL2 producing cells above 0.1% cut-off were considered protective, sensitivity of 75% and specificity 93% was achieved, while IFNγ-only production by more 0.3% cells had sensitivity of 88% but specificity of 73% only. Conclusions: Our study revealed functional signatures that are useful readout of immune monitoring. Furthermore, our data may modify the interpretation of previous studies that assessed only IFNγ. Supported by the Czech Ministry of Health grant NS/9996-4, MZØFNM2005 and Czech Ministry of Education MSMT21620813 Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2010-2010
Author(s):  
Irena Frydecka ◽  
Lidia Karabon ◽  
Edyta Pawlak-Adamska ◽  
Anna Tomkiewicz ◽  
Tomasz Wrobel ◽  
...  

Abstract Abstract 2010 Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been widely carried out as a therapy for several hematological malignances and non malignant disorders. Graft–versus -host disease is one of the major complications after allo-HSCT with main cause of morbidity and mortality. Donor T lymphocytes play the crucial role in alloimmune recognition and their ability to detect non –self antigens can lead to aGvHD. The effective recognition and activation of naïve T-cells requires two independent signals. The first, an antigen-specific signal, is sent via the T-cell receptor (TCR) on T-cells. The second signal, termed co-stimulation, is critical for allowing full activation, sustaining cell proliferation, preventing anergy and/or apoptosis, inducing differentiation to effector cells. CD28 is the primary T-cell co-stimulatory molecule. Cytotoxic T-cell antigen (CTLA-4) is a homologous molecule of CD28 which plays an inhibitory role in the early and late stages of T-cell activation. CTLA-4 ligation provides a negative signal for regulation of the cell cycle and inhibits the activity of the transcriptional factors: nuclear factor-kB (NF-kB), nuclear factor of activated T-cells (NF-AT), and activator protein 1 (AP-1). Moreover, CTLA-4 binds to CD28 ligands (CD80 and CD86) with higher affinity and avidity and in that way also inhibits T-cell activation. Since co-stimulatory and down regulatory molecules synthesis depend on the rate of gene transcription and/or translation, polymorphisms in the corresponding genes might result in abnormal expression, function as well as dysregulated trafficking of these molecules within cellular compartments. The human CTLA-4 gene is located on 2q33 which is susceptibility region for autoimmune diseases. The aim of this study is to investigate the associations between polymorphisms in CTLA-4 gene: CTLA-4c.49A>G (rs231775), CTLA-4g.319C>T (rs5742909), CTLA-4g6230G>A (CT60, rs3087243), CTLA-4g.10223G>T (Jo31, rs11571302) in donors of HSTC and occurrence of aGvH disease in recipients after allogeneic hematopoietic stem cell transplantation. Altogether 136 donors of HSCT (58- related donors, 88 haploidentical unrelated donors) were genotyped for all polymorphisms using allelic discrimination methods with the TaqManÒ SNP Genotyping Assay. In patients without aGvHD and in patients with aGvHD grade I-IV the similar distribution of alleles and genotypes for all investigated polymorphisms in donors was observed. However, we have noticed trend toward increased frequency of CT60 [G] donor allele among recipients with aGvHD I-IV (0.48 vs. 0.39, p=0.1, OR 1.49, 95% CI: 0.90–2.49) compared to recipients without aGvHD in whole group of patients. In patients transplanted from related donor also increased risk of aGvHD grade I-IV was observed for CT60 [G] donor allele (0.75 vs. 0.55, p=0.09, OR 2.11, 95%CI: 0.88–5.26). In contrary the frequencies of CT60 [G] donor allele in patients transplanted from unrelated donors are similar in recipients with and without aGvH symptoms. Haplotype estimation analysis indicated that donor haplotype CTLA-4c.49A>G[A], CTLA-4g.319C>T[C], CT60 [A], Jo31 [T] tended to be protective against aGvHD grade I-IV in whole studied group of patients (0.28 vs. 0.40, p=0.06, OR 0.60, 95% CI: 0.36–1.02) This association reach statistical significance in recipients of related transplantation (0.18 vs. 0.43, p=0.01, OR 0.29, 95% CI: 0.14–0.97) Our study indicated that donor CT60 polymorphism might be associated with occurrence of aGvHD, especially in recipients transplanted from HLA-identical sibling donors. Disclosures: No relevant conflicts of interest to declare.


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