Related Experiment Video
Updated: Feb 27, 2026

In Vitro and In Vivo Assessment of T, B and Myeloid Cells Suppressive Activity and Humoral Responses from Transplant Recipients
Published on: August 12, 2017
Effect of Single Sensitization Event on Human Leukocyte Antigen Alloimmunization in Kidney Transplant Candidates: A
Marianna Resse1, Rossella Paolillo, Biagio Pellegrino Minucci
1U.O.C. Division of Immunohematology, Transfusion Medicine and Transplant Immunology, Regional Reference Laboratory of Transplant Immunology, Azienda Ospedaliera Universitaria, Second University of Naples, Naples, Italy.
Objectives:
Human leukocyte antigen alloimmunization is caused by exposure to HLA antigens through transfusion, pregnancy, or transplant. Our study objective was to present the rate of positivity of anti-HLA antibody considering the effects of a single sensitization event in kidney transplant candidates at our center.
Materials And Methods:
Our study reviewed 606 kidney transplant candidates. Patient sera were analyzed using Luminex xMAP technology. Panel reactive antibody positivity rates and antibody strengths in patients were analyzed according to a single sensitization event.
Results:
Our findings showed 246 patients (40.6%) with a panel reactive antibody > 0, of which 97 (39.4%) were sensitized from a single event, 119 (48.4%) were sensitized by multiple events, and 30 (12.2%) had no known sensitizing event. Considering patients sensitized by a single event with a panel reactive antibody > 0, we found that 25.8% had received transplant only, 49.5% had previous pregnancy only, and 24.7% had received transfusion only. The strength of antibodies was significantly higher in patients with previous transplant procedures than in those with transfusion for HLA-A (P < .01), HLA-B (P < .05), HLA-C (P < .05), HLA-DR (P < .001), HLA-DQ (P < .05), and HLA-DP (P < .05). Similarly, we observed significantly higher median fluorescence intensity values for HLA-A, -DR, -DQ, and -DP loci in patients with a previous transplant procedure versus pregnancy. The strength of antibodies against HLA-DR was significantly higher in patients with a previous pregnancy compared with those with transfusion (P < .01).
Conclusions:
This study documents the profile of HLA alloimmunization in kidney transplant candidates. In particular, transplant procedures appear to have a greater immunologic impact, followed by pregnancy and transfusion. Our data confirm and are in accordance with those of several studies in which the sensitization events were associated with higher prevalence of anti-HLA antibodies.
Related Concept Videos
Kidney Transplant I: Introduction
Cell-mediated Immune Responses
Kidney Transplant II: Surgical Procedure
Drug Toxicity: Allergic Reactions

