Fabienne Pouthier

Effect of HLA-Matching Recipients to Donor Noninherited Maternal Antigens on Outcomes after Mismatched Umbilical Cord Blood Transplantation for Hematologic Malignancy

Transplantation-related mortality (TRM) is high after HLA-mismatched umbilical cord blood (UCB) transplantation (UCBT). In utero, exposure to noninherited maternal antigen (NIMA) is recognized by the fetus, which induces T regulator cells to that haplotype. It is plausible that UCBTs in which recipients are matched to donor NIMAs may alleviate some of the excess mortality associated with this treatment. To explore this concept, we used marginal matched-pair Cox regression analysis to compare outcomes in 48 NIMA-matched UCBTs (ie, the NIMA of the donor UCB unit matched to the patient) and in 116 non-NIMA-matched UCBTs. All patients had a hematologic malignancy and received a single UCB unit. Cases and controls were matched on age, disease, disease status, transplantation-conditioning regimen, HLA match, and infused cell dose. TRM was lower after NIMA-matched UCBTs compared with NIMA-mismatched UCBTs (relative risk, 0.48; P = .05; 18% versus 32% at 5 years posttransplantation). Consequently, overall survival was higher after NIMA-matched UCBT. The 5-year probability of overall survival was 55% after NIMA-matched UCBTs versus 38% after NIMA-mismatched UCBTs (P = .04). When faced with the choice of multiple HLA-mismatched UCB units containing adequate cell doses, selecting an NIMA-matched UCB unit may improve survival after mismatched UCBT.

Increased production of soluble CTLA-4 in patients with spondylarthropathies correlates with disease activity

IntroductionSpondylarthropathies (SpA) are characterized by abnormal immune responses including T cell activation. Cytotoxic T lymphocyte associated molecule-4 (CTLA-4) is involved in down-regulating immune responses. A soluble form of CTLA-4 (sCTLA-4), resulting from an alternative splicing, has been identified and was found increased in several autoimmune diseases. Here, we evaluated circulating levels of sCTLA-4 as a marker of immune dysregulation in SpA. Intracellular CTLA-4 and levels of CTLA-4 transcript expression in peripheral blood lymphocytes (PBL) were also studied.MethodsSera from 165 patients with SpA were evaluated for sCTLA-4 measurements. Results were compared with those from 71 patients with rheumatoid arthritis (RA) and 88 healthy subjects. In 32 patients with SpA, 22 patients with RA and 15 healthy controls, we analyzed the intracellular CTLA-4 expression in CD4+ T cells, CD8+ T cells, activated (HLA-DR+Foxp3-) CD4+ T cells, CD4+ regulatory (CD25+Foxp3+) T cells and in CD3 negative cells by flow cytometry. Expression of the full length (coding for membrane CTLA-4) and spliced form (coding for sCTLA-4) of CTLA-4 transcripts in PBL were analyzed by quantitative real-time polymerase chain reaction (QRT-PCR).ResultsHigh levels of sCTLA-4 were found in the SpA group compared to the RA group and healthy controls (P < 0.0001). Soluble CTLA-4 serum levels strongly correlated with clinical index of disease activity BASDAI (r = 0.42, P < 0.0001) and C-reactive protein (CRP) levels (r = 0.17, P = 0.037). In contrast to RA patients, SpA patients did not exhibit changes in intracellular CTLA-4 expression in the different PBL subsets tested. Finally, the SpA group showed a preferential expression of the spliced CTLA-4 mRNA (P = 0.0014) in PBL.ConclusionsSpA patients exhibit high levels of circulating sCTLA-4 that may result from an alternative splicing of CTLA-4 transcripts. This may influence immune activation and regulation in SpA.

Engraftment kinetics and graft failure after single umbilical cord blood transplantation using a myeloablative conditioning regimen

Umbilical cord blood transplant recipients are exposed to an increased risk of graft failure, a complication leading to a higher rate of transplant-related mortality. The decision and timing to offer a second transplant after graft failure is challenging. With the aim of addressing this issue, we analyzed engraftment kinetics and outcomes of 1268 patients (73% children) with acute leukemia (64% acute lymphoblastic leukemia, 36% acute myeloid leukemia) in remission who underwent single-unit umbilical cord blood transplantation after a myeloablative conditioning regimen. The median follow-up was 31 months. The overall survival rate at 3 years was 47%; the 100-day cumulative incidence of transplant-related mortality was 16%. Longer time to engraftment was associated with increased transplant-related mortality and shorter overall survival. The cumulative incidence of neutrophil engraftment at day 60 was 86%, while the median time to achieve engraftment was 24 days. Probability density analysis showed that the likelihood of engraftment after umbilical cord blood transplantation increased after day 10, peaked on day 21 and slowly decreased to 21% by day 31. Beyond day 31, the probability of engraftment dropped rapidly, and the residual probability of engrafting after day 42 was 5%. Graft failure was reported in 166 patients, and 66 of them received a second graft (allogeneic, n=45). Rescue actions, such as the search for another graft, should be considered starting after day 21. A diagnosis of graft failure can be established in patients who have not achieved neutrophil recovery by day 42. Moreover, subsequent transplants should not be postponed after day 42.

Incidence and risk factors of anti-HLA immunization after pregnancy

Pregnancy is the only natural source of anti-HLA immunization. The exact frequency of this immunization remains undetermined as prior studies either used methods with a low sensitivity or were performed late after delivery. We present here the first study on women at delivery evaluating anti-HLA immunization by Luminex. We also attempted to isolate factors influencing immunization, such as soluble HLA-G (sHLA-G) levels and genetic polymorphisms. With Luminex, anti-HLA immunization was observed in 54.4% of the women. As expected, immunization frequency increased with the number of children, reaching 74% in women with >2 deliveries. Among immunized women, strong cytotoxic Ab (as detected by Complement Dependent Cytotoxicity) were associated with a lower level of sHLA-G. None of the studied polymorphisms influenced immunization rate in the whole cohort. Among 94 first pregnant women with no history of miscarriage, the -174 IL-6 gene promoter mutation (G/C) appeared more frequently in non immunized women (69% vs. 45% in immunized ones, p=0.02). Lastly, the occurrence of a miscarriage before the first live delivery significantly decreased immunization. These results may help to understand mechanisms of pregnancy induced immunization. They also have an impact in the management of previous pregnant women requiring organ or hematopoietic stem cell transplantation.

Persistence of lymphocyte function perturbations after granulocyte–colony‐stimulating factor mobilization and cytapheresis in normal peripheral blood stem cell donors

BACKGROUND: The short‐term effects of granulocyte–colony‐stimulating factor (G‐CSF) have been extensively studied, but recent reports of G‐CSF–induced genetic perturbations raised concerns regarding its long‐term safety. In this respect, duration of G‐CSF–induced perturbations has been less studied than short‐term effects and needs to be evaluated.

G-CSF-induced aneuploidy does not affect CD34+ cells and does not require cell division.

To the editor: Lymphocytes from granulocyte colony-stimulating factor (G-CSF)–mobilized donors display epigenetic and genetic alterations similar to those observed in leukemia patients.[1][1] To further evaluate the scope and duration of G-CSF–induced genetic alterations, 24 healthy donors were

Quality controls on cord blood unit contiguous segments: recommendation of the SFGM-TC.

In the attempt to harmonize clinical practices between different French transplantation centers, the French Society of Bone Marrow Transplantation and Cell Therapies (SFGM-TC) set up its fourth annual series of workshops which brought together practitioners from all of its member centers. These workshops took place in September 2013 in Lille. Literature and intra-laboratories studies suggest that attached segment is representative of cord blood unit (CBU). Nevertheless, some discrepancies have been observed when analyzing large data registries. To address these issues, we have listed recommendations to increase the standardization of segment processing and quality control (QC), information on units of measurement and specifications and action to be taken in case of out of specifications QC results on segment.

Diagnosis and management of nocardiosis after bone marrow stem cell transplantation in adults: Lack of lymphocyte recovery as a major contributing factor

Hematopoietic cell transplantation (HCT) is a curative treatment for hematological malignancies. This therapeutic approach is associated with a profound immune deficiency and an increased rate of opportunistic infections. Nocardiosis is a rare bacterial infection occurring mainly in patients with deficient cell-mediated immunity, such as AIDS patients or transplant recipients. Diagnosis of nocardiosis can be challenging, as signs and symptoms are non-specific. Routine prophylaxis with trimethoprin/sulfamethoxazole (TMP/SMZ) does not prevent the risk of infection. Between May 2001 and December 2009, five cases of nocardiosis were diagnosed from the 366 allogeneic HCT recipients in our centre. Four patients developed a disseminated nocardiosis within the first year after HCT. The fifth patient presented a localized cutaneous nocardiosis. In disseminated cases, median total CD4+ T-cells were below 100 cells/μL. Naive CD4+ CD45RA+/RO- T-cells were almost undetectable. CD8(+) T-cells and NK cells were below the normal range and CD19+ B-cell reconstitution was completely deficient. In a localized case, we observed a lack of naive thymic emigrants CD4+ CD45RA+/RO- T-cells.

Evaluation of microbial contamination of corneal transplants: one-year report from a French regional eye bank.

Purpose: The aim of this study was to report the rate of corneal transplant microbial contamination in a single major eye bank and to identify the contributive factors. Methods: The contamination rate of 1156 organ-cultured corneas harvested in 2010 in a single eye bank (EFS Bourgogne Franche-Comté, Besançon, France) was studied together with the following factors: age, sex, tissue-recovery method (single or multiorgan donors), death-to-excision time, excision-to-reception time, cause of death, positive serology, and endothelial cell count. Student t test for quantitative data was used for statistical comparisons between groups. Qualitative data were assessed using the &khgr;2 test. Results: The contamination rate was 5.5%. Most contaminations were of bacterial origin (77.9%), with Staphylococcus species (62.3%) being predominant. Fungal contaminations (19.1%) were dominated by Candida species (76.9%). Death resulting from cancer was related to a higher risk of corneal contamination (P < 0.001). The other factors were not related to an increased risk of contamination. Conclusions: The rate of microbiological contamination of corneal transplants remains low. However, special caution should be exercised with grafts collected from patients dying from cancer. To minimize this risk, further studies on the antibacterial effect of the conservation media should be conducted in the context of increased bacterial resistance.

Early immune reconstitution and efficient graft vs tumor effect after unrelated partially matched double cord blood transplantation in refractory 8p11 syndrome

Early immune reconstitution and efficient graft vs tumor effect after unrelated partially matched double cord blood transplantation in refractory 8p11 syndrome