AM25-MN-13-L - AABB/ASHI Symposium: Exploring Transplant Uncertainties/Conundrums in ABO

Monday, October 27, 2025

10:00 AM - 11:30 AM PT

Room: SDCC 33

CE: 1.5 CME (AMA Physician Credit) / 1.5 CE (Non-Physician Credit)

Program Chair(s)

PK

Patricia M. Kopko, MD

Medical Director
pkopko@health.ucsd.edu, California

Disclosure(s): No financial relationships to disclose

Handouts

Speaker(s)

Anne Halpin, PhD CHS S(ACHI) (she/her/hers)

Assistant Professor
University of Alberta
Edmonton, Alberta

Disclosure(s): GlycoBead Diagnostics: IP related to transplant diagnostics (Ongoing)

Handouts
Amena Usmani, MD (she/her/hers)

Associate Professor of Pathology
University of California San Diego Health, California

Disclosure(s): No financial relationships to disclose

Handouts
HS

Harold Sullivan, MD

Emory University, Georgia

Disclosure information not submitted.

Handouts

The session is designed to review policy and practice related to ABO-incompatible transplantation. There will be a multidisciplinary approach including surgery, the histocompatibility laboratory and the transfusion service, which all need to work together to make ABO incompatible solid organ transplantation possible. The clinical need for increased ABO incompatible solid organ transplants, particularly renal transplant and pediatric heart transplants will be presented. ABO-histocompatibility testing and the current methods used to determine ABO immune risk assessment will be reviewed. The science surrounding the differential expression of ABO antigens on red blood cells versus endothelial cells and other solid organ tissues will be emphasized to demonstrate that testing of antigens on red blood cells may not adequately represent the ABO antigens in donor tissues. The variability in ABO antibody titers will be reviewed and the need for the automation of ABO antibody titers in resource constrained transfusion services to better support ABO incompatible solid organ transplants will be discussed. The session will end with an open forum for discussion.

Learning Objectives:

Explain why ABO incompatible renal and pediatric heart transplants are needed in the United States.
Contrast ABO antigen expression, including A2 expression, on red blood cells to expression on vascular endothelium and other tissues in solid organs.
Describe why automation of anti-A and anti-B titers in blood banks can increase the ability of transfusion services to support ABO incompatible solid organ transplants.
Describe the evolving use of A2 titers in solid organ transplantation.