[Biobanking in a histocompatibility laboratory. Guidelines from the Francophone Society of Histocompatibility and Immunogenetics (SFHI)]. / Critères de conservation des échantillons biologiques dans un laboratoire d'histocompatibilité Les recommandations de la Société francophone d'histocompatibilité et d'immunogénétique (SFHI).

Histocompatibility laboratories perform the biological analyses linked related to organ transplant, hematopoietic stem cells transplant, some immune dysfunction diseases and immuno-allergy after therapeutic treatment. Most of these analyses are prospectively or retrospectively performed on sera and DNA. The Société Francophone d'Histocompatibilité et d'Immunogénétique (SFHI) has made some recommendations in order to define storage conditions and storage lifetime of the samples required in a histocompatibility laboratory. These recommendations have been drawn up by a working group of ten biologists. They have been established on literature review and data from method validation, which has been already performed within French laboratories (collected through a national questionnaire sent to participant laboratories). The recommendations made by the SFHI for the storage of samples for immunogenetics analyses facilitate the harmonization of practices among histocompatibility laboratories.

T lymphocyte immunophenotyping in bronchoalveolar lavage on AQUIOS CL® cytometer.

Bronchoalveolar lavage (BAL) is one of the tests for orientation in the diagnosis of diffuse parenchymal lung disease. Lymphocyte subpopulation study by flow cytometry in the BAL is part of the criteria for the diagnosis of sarcoidosis. We investigated the feasibility of T lymphocyte immunophenotyping in BAL on a new automaton: AQUIOS CL®, a closed access cytometer with fully automated process designed for blood samples. Repeatability and contamination studies showed acceptable results (variation coefficients <5% and contamination indices <1%). We also compared BAL immunophenotyping results performed on AQUIOS CL® with those performed with an open access cytometer: Navios®. The correlation coefficient r is close to 1 on the studied parameters. The number of unacceptable measurement deviations is <5% and does not affect the biological interpretation of the results indicating a good correlation between the two automata. These results show that immunophenotyping in BAL is feasible on AQUIOS CL®.

Standardization of the capillary electrophoresis procedures Capillarys® CDT and Minicap® CDT in comparison to the IFCC reference measurement procedure.

CDT is at present the most relevant routinely available biological marker of alcohol use and is widely used for screening and monitoring of patients. The lack of standardization leads to specific reference intervals for each procedure. The IFCC working group devoted to CDT demonstrated that the standardization is possible using calibrators assigned to the reference measurement procedure. In this study, we compare the capillary electrophoresis (CE) techniques Capillarys® CDT and Minicap® CDT (Sebia, Lisses, France) to the reference procedure before and after standardization in 126 samples covering the range of CDT measurement. Both capillary electrophoresis procedures show a high correlation (r=0,997) with the reference procedure and the concordance correlation coefficient evaluated according to Mc Bride is "almost perfect" (>0.997 for both CE procedures). The number of results with a relative difference higher than the acceptable difference limit is only 1 for Capillarys® CDT and 5 for Minicap® CDT. These results demonstrate the efficiency of the standardization of CDT measurements for both CE techniques from Sebia, achieved using calibrators assigned to the reference measurement procedure.

Discovery of a gamma heavy chain disease in a patient followed-up for a lymphoplasma cell proliferative disorder.

Gamma-heavy chains disease is a rare disease, with very few cases described in the literature. It is characterized by the presence of a monoclonal gamma-heavy chain without associated light chain. Its prevalence and prognosis are unknown. We report here the accidental discovery of a case of gamma-heavy chain disease during a pancytopenia exploration, performed in the hospital, in a patient known since 2002 for a lymphoplasmacytic type lymphoma first localized in bone marrow.