No abstract

Fourth-generation human immunodeficiency virus-1 (HIV-1) screening assays have improved sensitivity, but vary in performance characteristics. The purpose of this study was to evaluate four different fourth-generation HIV-1 assays. These assays included the AxSYM HIV Ag/Ab Combo (Abbott diagnostics, Delkenheim, Germany), ARCHITECT HIV Ag/Ab Combo (Abbott), Elecsys 2010 HIV Combi (Roche Diagnostics GmbH, Mannheim, Germany), and Elecsys HIV Combi PT (Roche). A total of 1,306 samples that included 1,225 clinical samples and 81 samples consisting of seroconversion panels, an HIV-1 p24 antigen sensitivity panel, and dilution series of HIV-1 lysates and HIV-1 antibodies were tested. All of the assays had sensitivities of 100% on clinical samples. The specificities of the AxSYM, ARCHITECT, Elecsys 2010 HIV Combi, and Elecsys HIV Combi PT were 99.6, 99.6, 99.0, and 99.5%, respectively. Of the 81 samples with different levels of HIV antigen or antibody and/or subtypes, Elecsys HIV Combi PT and ARCHITECT HIV Ag/Ab Combo showed better analytical sensitivities than the other two assays. In summary, the performance characteristics of AxSYM, ARCHITECT, and Elecsys HIV Combi PT were comparable and satisfactory for clinical samples. ARCHITECT HIV Ag/Ab Combo and Elecsys HIV Combi PT have the higher analytical sensitivities, and would be preferable for reducing the window period.

Several studies have suggested that a positive lymphocyte cross-matching (XM) is associated with low graft survival rates and a high prevalence of acute rejection after adult living donor liver transplantations (ALDLTs) using a small-for-size graft. However, there is still no consensus on preoperative desensitization. We adopted the desensitization protocol from ABO-incompatible LDLT. We performed desensitization for the selected patients according to the degree of T lymphocyte cross-match titer, model for end-stage liver disease (MELD) score, and graft liver volume. We retrospectively evaluated 230 consecutive ALDLT recipients for 5 yr. Eleven recipients (4.8%) showed a positive XM. Among them, five patients with the high titer (> 1:16) by antihuman globulin-augmented method (T-AHG) and one with a low titer but a high MELD score of 36 were selected for desensitization: rituximab injection and plasmapheresis before the transplantation. There were no major side effects of desensitization. Four of the patients showed successful depletion of the T-AHG titer. There was no mortality and hyperacute rejection in lymphocyte XM-positive patients, showing no significant difference in survival outcome between two groups (P=1.000). In conclusion, this desensitization protocol for the selected recipients considering the degree of T lymphocyte cross-match titer, MELD score, and graft liver volume is feasible and safe.Graphical Abstract

No abstract

AIMTo investigate the rates of pretransplantation fetal-maternal microchimerism (MC) and its effect on rejection in children receiving maternal liver grafts.METHODSDNA or blood samples before liver transplantation (LT) were available in 45 pediatric patients and their mothers. The presence of pretransplantation MC to non-inherited maternal antigens (NIMAs) (NIMA-MC) in the peripheral blood was tested using nested PCR-single-strand conformation polymorphism analysis for the human leukocyte antigen (HLA)-DRB1 alleles. NIMA-MC was successfully evaluated in 26 of the 45 children. Among these 45 pediatric LT recipients, 23 children (51.1%) received transplants from maternal donors and the other 22 from non-maternal donors.RESULTSAmong these 26 children, pretransplantation NIMA-MC was detected in 23.1% (n = 6), 6.1 (range, 0.8-14) years after birth. Among the children with a maternal donor, the rate of biopsy-proven cellular rejection (BPCR) was 0% in patients with NIMA-MC positivity (0/3) and those with HLA-DR identity with the mother (0/4), but it was 50% in those with NIMA-MC negativity (5/10). Patients with NIMA-MC positivity or HLA-DR identity with the mother showed significantly lower BPCR rate compared with NIMA-MC-negative patients (0% vs 50%, P = 0.04). NIMA-MC-positive patients tended to show lower BPCR rate compared with NIMA-MC-negative patients (P = 0.23).CONCLUSIONThe presence of pretransplantation NIMA-MC or HLA-DR identity with the mother could be associated with BPCR-free survival in pediatric recipients of LT from maternal donors.