Vall d’Hebron has entered into a research collaboration with Pure Transplant Solutions, LLC (PTS), a collaboration driven biotechnology company focused on the development of human leukocyte antigen (HLA)-based diagnostics and therapeutics within the field of transplantation, to develop new technologies for B-cell monitoring in transplant rejection. 

The research is being led by Drs. Oriol Bestard, head of the Nephrology and Kidney Transplant group at Vall d’Hebron Research Institute (VHIR) and Rico Buchli and focuses on the detection of alloreactive memory B cells for pre-transplant risk stratification and post-transplant monitoring. Recognition of non-self HLA gives rise to the formation of HLA-specific memory B cells which precede circulating HLA antibodies. Importantly, such HLA-specific memory B cells can be present even in the absence of detectable serum antibodies, being an additional rejection risk factor in transplantation. Memory B cells are responsible for immunological recall responses by differentiating into antigen-specific antibody-producing cells upon re-encounter with a miss-matched antigen. 

“This collaboration with PTS validates the tremendous need for appropriate and routinely applicable assays to detect and visualize the presence and HLA specificity of alloreactive memory B cells in solid organ transplant patients, which may ultimately help improve current alloimmune-risk stratification”, Dr. Bestard stated. 

“Today, the immunological risk of an individual transplant patient is mainly assessed by detection of HLA antibodies in the serum, which are produced by long lived bone marrow-residing plasma cells. At PTS, we envision that in addition to serum HLA antibody detection, HLA-specific memory B cell assays will serve as supplemental tools to determine risk factors and help improve individual patient management”, said Dr. Buchli.

Steve Mayer MD, Chief Medical Officer at PTS stated, “We’re very excited about the potential of this technology because it allows a very early diagnostic view of an individual’s risk of rejection before any graft damage has occurred. Also, the technology is likely to have a significant impact on clinical utility with high predictive values.”