HLA-DRB3/4/5 mismatches are associated with increased risk of acute GVHD in 10/10 matched unrelated donor hematopoietic cell transplantation.

Matching for HLA-A, -B, -C, and -DRB1 loci (8/8 match) is currently the gold standard for unrelated donor hematopoietic cell transplantation (HCT). In Europe, patients are also matched at the HLA-DQB1 loci (10/10 match). However, there is increasing evidence that matching at HLA-DRB3/4/5 loci may help to lower transplant-related morbidity and mortality. We therefore investigated the impact of HLA-DRB3/4/5 mismatches on outcomes in 1975 patients who received a first 10/10 matched unrelated donor (MUD) HCT in France from 2000 to 2012 for a hematological malignancy. High-resolution typing was performed at HLA-A, -B, -C, -DRB1, -DQB1, -DPB1, and -DRB3/4/5 loci for all donor/recipient pairs. Compared with DRB3/4/5-matched pairs, patients who received a MUD HCT from a DRB3/4/5 mismatched donor had a significantly increased risk of grade II-IV acute graft-versus-host disease (aGVHD) (Adjusted Hazard Ratio (HR) 1.43 (1.07 to 1.90)) associated with lower graft-versus-host disease-free and relapse-free survival (GRFS) (Adjusted HR 1.20 (1.02 to 1.42)). Conversely, we observed no differences in terms of chronic GVHD, nonrelapse mortality, relapse and overall survival. However, we believe that patients stand to benefit from DRB3/4/5 loci being considered for unrelated donor selection to improve GRFS and then quality of life after unrelated HCT.

The novel HLA-B*14:118 allele characterized by two different sequencing-based typing techniques.

HLA-B*14:118 differs from HLA-B*14:93 by two non-synonymous and one synonymous nucleotide substitution in exon 2.

Human leukocyte antigen-B27 typing by flow cytometry: Comparison of three CE-IVD methods.

BACKGROUND: The human leukocyte antigen B27 (HLA-B27), associated with chronic inflammatory diseases is thus widely performed for diagnostic purposes. Genotyping by molecular biology is the current gold standard for HLA-B27 typing, but cheaper and faster flow cytometry methods have been developed. METHODS: In this report, we compare analytical performances of three CE-IVD flow cytometry kits: IOTest™ and DuraClone B27™ from Beckman Coulter and BD HLA-B27™ from BD Biosciences on a Navios™ cytometer as compared to molecular biology. RESULTS: Routine analyses could conclude for HLA-B27 in197 patients (23.2%) and was not conclusive for 66 patients (7%, 8%). The experience revealed the needs to complete IOTest™ with a lineage marker (like CD3-APC) and a standardization procedure in detection of fluorescence. Comparative analysis considering 23/44 non-conclusive samples as negative, pointed out a 100% sensitivity and specificity of IOTest™ in determining genetically proved HLA-B27. Specificity of the BD HLA-B27TM kit was 94% (two false positives) sticking to the manufacturer instructions but raised to 100% and 94% sensitivity with a cutoff at 8.5 (225 on FACSdiva's scale). DISCUSSION: The DuraClone B27™ specificity was poor using the manufacturer cutoff but raised to 100% with a 8.0 cutoff instead of 15. CONCLUSION: The three flow cytometry kits displayed satisfying performances but need adjustments. The DuraClone B27™ kit seems to be the best while the IOTest™ kit is not conclusive in 8% of cases. In most cases the use of molecular biology can be spared, but genotyping remains essential for patients whose HLA-B27 status cannot be determined with confidence by flow cytometry.

The MHC class I MICA gene is a histocompatibility antigen in kidney transplantation.

The identity of histocompatibility loci, besides human leukocyte antigen (HLA), remains elusive. The major histocompatibility complex (MHC) class I MICA gene is a candidate histocompatibility locus. Here, we investigate its role in a French multicenter cohort of 1,356 kidney transplants. MICA mismatches were associated with decreased graft survival (hazard ratio (HR), 2.12; 95% confidence interval (CI): 1.45-3.11; P < 0.001). Both before and after transplantation anti-MICA donor-specific antibodies (DSA) were strongly associated with increased antibody-mediated rejection (ABMR) (HR, 3.79; 95% CI: 1.94-7.39; P < 0.001; HR, 9.92; 95% CI: 7.43-13.20; P < 0.001, respectively). This effect was synergetic with that of anti-HLA DSA before and after transplantation (HR, 25.68; 95% CI: 3.31-199.41; P = 0.002; HR, 82.67; 95% CI: 33.67-202.97; P < 0.001, respectively). De novo-developed anti-MICA DSA were the most harmful because they were also associated with reduced graft survival (HR, 1.29; 95% CI: 1.05-1.58; P = 0.014). Finally, the damaging effect of anti-MICA DSA on graft survival was confirmed in an independent cohort of 168 patients with ABMR (HR, 1.71; 95% CI: 1.02-2.86; P = 0.041). In conclusion, assessment of MICA matching and immunization for the identification of patients at high risk for transplant rejection and loss is warranted.

[Definition and standardization of histocompatibility requests depending on patient course and donor type: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) and the Francophone Society of Histocompatibility and Immunogenetics (SFHI)]. / Définition et standardisation des bilans d'histocompatibilité en fonction du parcours du patient et du type de donneur : recommandations de la Société francophone de greffe de moelle et de thérapie cellulaire (SFGM-TC) et de la Société Francophone d'Histocompatibilité et Immunogénétique (SFHI).

Standardization of histocompatibility tests for allogeneic hematopoietic cell transplants, harmonization of information transmitted to clinicians are part of quality improvement and optimization of human and economic resources. New HLA typing technologies provide high-resolution information within a reasonable time frame. Knowledge of high-resolution HLA typing for the patient and their relatives is essential for a better interpretation of compatibilities. HLA-DPB1 typing must be considered in transplant field regardless of the donor type. The benefits of using search and match programs are considerable. It saves time and reduces additional typing costs by providing rapid information about the likelihood to identify a matched unrelated donor. A backup therapy considering alternative cell sources or treatment can therefore be quickly implemented. The importance of knowledge and consideration of patient immunization for donor choice was explored in previous workshops of the SFGM-TC (2018 and 2019). The published recommendations remain applicable. The routine follow-up protocol and in case of desensitization will be detailed here. This harmonization must be accompanied by the standardization of information to be returned to the clinician regarding the donor finding possibilities for the patient. This will guarantee a similar quality level in every center.

Expression of functional toll-like receptors by B-chronic lymphocytic leukemia cells.

This study reports that B-chronic lymphocytic leukemia (B-CLL) cells display the same pattern of toll-like receptors (TLRs) proteins expression as normal B-cells, yet with overexpression of TLR9. Furthermore, TLR7 and TLR9 appear to be functional and liable to respond to specific ligands, respectively imidazoquinolines and CpG-ODN thus potentially opening new therapeutic approaches.

[HLA coding in ProMISe: Guidelines from the Francophone Society of bone marrow transplantation and cellular therapy (SFGM-TC)]. / Codage HLA dans ProMISe : recommandations de la Société francophone de greffe de moelle et de thérapie cellulaire (SFGM-TC).

As part of the 7th Annual francophone workshop series on the harmonization of clinical practices in allogeneic stem cell transplantation held in Lille in September 2016, our workgroup discussed how transplant centers might follow a collective approach to coding data. This was done mainly by analyzing the study results found in the literature that do not provide clear answers. In addition, we discuss practical ways of coding for both donor and recipient HLA typing in the European bone marrow transplantation database called ProMISe which is managed by the European Society for Blood and Marrow Transplantation (EBMT).

[Polymorphism in HLA and KIR genes and the impact on hematopoietic stem cell transplantation outcomes and unrelated donor selection: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]. / Polymorphisme des gènes HLA et KIR et l'impact sur le devenir de la greffe et le choix du donneur non apparenté de cellules souche hématopoïétiques : recommandations de la Société francophone de greffe de moelle et de thérapie cellulaire (SFGM-TC).

In an attempt to harmonize clinical practices among French hematopoietic stem cell transplantation centers, the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) held its sixth annual workshop series in September 2015 in Lille. This event brought together practitioners from across the country with the purpose of offering careful analysis of published studies on clinical practice issues that remain to be disputed. This article addresses the impact of HLA and KIR gene polymorphism on the outcome of the transplantation in order to optimize unrelated donor selection.

Fatal peri-operative hyperacute graft rejection during heart transplantation related to infusion of red blood cell concentrate.

With the use of sensitive new technology, hyperacute graft rejection is currently reported as an extremely rare event due to prospective lymphocyte crossmatches and/or virtual crossmatches. In this case study we describe a case of fatal early graft failure after a cardiac transplant in a male recipient who had no anti-HLA antibodies detected before transplantation, but who received, during heart transplant surgery, a red blood cell concentrate containing high levels of graft-specific alloantibodies. In addition, we analyze the relationship between these alloantibodies and the occurrence of hyperacute allograft rejection.

Rapid generation of full clinical-grade human antiadenovirus cytotoxic T cells for adoptive immunotherapy.

Adenovirus (ADV) infections are one of the major causes of morbidity and mortality after hematopoietic stem cell transplantation, despite new antiviral treatment strategies. We describe here a complete clinical-grade generation of human anti-ADV cytotoxic T cells to propose an adoptive immunotherapy. Peripheral blood mononuclear cells (PBMC) from 7 healthy donors, known for their good cellular immunity against ADV, were stimulated for 6 hours with a synthetic peptide pool covering the ADV5 Hexon protein interferon-gamma (IFN-gamma) secreting cells were isolated on a clinical device. After immunoselection, a mean number of 1.01 +/- 0.84 x 10(6) total nucleated cells was obtained. The isolated ADV-specific T cells were mainly CD4+ (mean=56% +/- 20.8%, yield=51% +/- 32.4%) but also CD8+ (mean=42% +/- 27%, yield = 56% +/- 39.3%). Isolated T lymphocytes (CTL) were expanded to carry out functional tests. Ability of the expanded CTL to secrete IFN-gamma and to proliferate after restimulation with the ADV peptide pool was confirmed. A high cytotoxicity against autologous target cells loaded with ADV antigens was observed but not against nonloaded target cells. We observed a decrease of 1.27 log of the allogeneic reaction against non HLA identical healthy donor PBMC with CTL compared with the PBMC before selection. Clinical-grade generation of ADV-specific T cells was achieved with a synthetic antigen. This technology has the advantage of being fast, and is sufficiently reactive to be proposed for immunotherapy if antiviral treatment fails.

Unexpected anti-HLA-DR and -DQ alloantibodies after nephrectomy of an HLA-DR and -DQ identical first renal transplant.

The development of the single antigen beads assay by Luminex technology enables accurate identification of allele-specific antibodies. Herein, we report the identification of donor-specific HLA-DR and -DQ antibodies in a first kidney transplant recipient who received a DR and DQ identical kidney transplant. The recipient was a non-sensitized, non-transfused male patient suffering from an end-stage renal failure due to focal and segmental glomerulosclerosis. Two weeks after graft nephrectomy, anti-class I (donor-specific and non-donor specific) and class II antibodies were detected. The single antigen beads technique identified class II antibodies directed against DRB3*0202 and HLA-DQB1*0603 alleles. High-resolution class II typing revealed five allelic incompatibilities between donor and recipient. Amino-acid sequence alignment showed why this post-transplant highly immunized patient developed only these two allele-specific antibodies. Minimizing HLA mismatches between donor and recipient is important, but it is also useful to consider the combination of all HLA molecules present in the donor and recipient in order to define the antibody epitopes responsible for alloantibody responses.

Measurement of immunoglobulins G, A, and M levels in B-lymphocytes culture.

Nephelometric immunoassays were developed for human IgG, IgA, and IgM quantitation in B-lymphocytes culture media. They allowed measurement of immunoglobulin (Ig) levels over a broad range of concentrations with good accuracy and precision. The kinetics of Ig production in B-lymphocyte cultures was followed and the mean amount of each Ig was determined in six different samples after three days of culture. The nephelometric immunoassays reported here could be used to study, in vitro, the influence of various molecules (inhibitory or amplifying effect) on B-lymphocytes' functional capacities.