Clinical recommendations for posttransplant assessment of anti-HLA (Human Leukocyte Antigen) donor-specific antibodies: A Sensitization in Transplantation: Assessment of Risk consensus document.

Although anti-HLA (Human Leukocyte Antigen) donor-specific antibodies (DSAs) are commonly measured in clinical practice and their relationship with transplant outcome is well established, clinical recommendations for anti-HLA antibody assessment are sparse. Supported by a careful and critical review of the current literature performed by the Sensitization in Transplantation: Assessment of Risk 2022 working group, this consensus report provides clinical practice recommendations in kidney, heart, lung, and liver transplantation based on expert assessment of quality and strength of evidence. The recommendations address 3 major clinical problems in transplantation and include guidance regarding posttransplant DSA assessment and application to diagnostics, prognostics, and therapeutics: (1) the clinical implications of positive posttransplant DSA detection according to DSA status (ie, preformed or de novo), (2) the relevance of posttransplant DSA assessment for precision diagnosis of antibody-mediated rejection and for treatment management, and (3) the relevance of posttransplant DSA for allograft prognosis and risk stratification. This consensus report also highlights gaps in current knowledge and provides directions for clinical investigations and trials in the future that will further refine the clinical utility of posttransplant DSA assessment, leading to improved transplant management and patient care.

Sensitization in transplantation: Assessment of Risk 2022 Working Group Meeting Report.

The Sensitization in Transplantation: Assessment of Risk workgroup is a collaborative effort of the American Society of Transplantation and the American Society of Histocompatibility and Immunogenetics that aims at providing recommendations for clinical testing, highlights gaps in current knowledge, and proposes areas for further research to enhance histocompatibility testing in support of solid organ transplantation. This report provides updates on topics discussed by the previous Sensitization in Transplantation: Assessment of Risk working groups and introduces 2 areas of exploration: non-human leukocyte antigen antibodies and utilization of human leukocyte antigen antibody testing measurement to evaluate the efficacy of antibody-removal therapies.

Predictive value of mixed antigen screen beads in pre-transplant assessment of HLA immunization in solid organ transplant recipients.

Pre-transplant serum screening of anti-HLA antibodies is recommended for solid organ transplantations. Many laboratories use the less expensive bead-based screening assay as the main technique and, if positive, turn to single-antigen beads (SAB). We studied the correlations between these two immunoassays. We re-analyzed the raw data of the two assays in 3030 first organ transplant recipients, explored with the two tests. We performed a ROC curve analysis of the screening ratio to predict a positive SAB assay. The AUC were 0.72 and 0.64 for class I and class II. The optimal thresholds of screening ratios were 3.28 (class I) and 2.11 (class II). Whatever the class, the negative predictive value was low, around 40%, with 36% of discordant sera, as defined by negative screening and positive SAB. Testing class I discordant sera on acid-treated SAB showed that 54% of antibodies reacted against denatured HLA molecules. However, these screening-negative sera may contain donor-specific antibodies in 13.9% and 28.7% of cases for class I and class II, respectively, involved in antibody-mediated rejection with the same frequency as non-discordant sera. Given the low predictive value of screening, both assays should be performed at least once on the same serum before transplantation.

Assessment of leukemia inhibitory factor levels by uterine flushing at the time of egg retrieval does not adversely affect pregnancy rates with in vitro fertilization.

OBJECTIVE: To assess intrauterine levels of leukemia inhibitory factor (LIF) by uterine flushing at the time of egg retrieval and to confirm that the procedure has no detrimental effect on pregnancy rates. DESIGN: Prospective study. SETTING: Assisted reproductive unit of a university hospital. PATIENT(S): Uterine flushing was performed in 148 IVF patients. The first 100 patients were compared with a matched control group. INTERVENTION(S): Uterine flushing at the time of egg retrieval. MAIN OUTCOME MEASURE(S): IVP-ET results, pregnancy rates, and intrauterine LIF levels. RESULT(S): Pregnancy rates were not different in the group of patients with (27%) or without uterine flushing (28%). Leukemia inhibitory factor was detected in 60 patients (46%). Pregnancy rates did not differ between patients' detectable LIF and those in whom LIF was undetectable. Mean levels of LIF were 30.1 +/- 49.3 pg/mL and 28.6 +/- 51.2 pg/mL in pregnant and nonpregnant patients respectively. CONCLUSION(S): The flushing procedure at the time of egg retrieval did not adversely affect pregnancy rates. Leukemia inhibitory factor was detected in 46% of patients at the time of egg retrieval, but no correlation were observed with better pregnancy rates in patients with detectable LIF. Mean LIF levels did not differ in pregnant and nonpregnant women. Access to endoluminal secretions of the endometrium during IVF-ET may represent a new research in human implantation.