Detection of engraftment of donor-derived antibody producing cells in a lung transplant recipient by anti-cytomegalovirus IgG avidity test

Transfer of donor anti-HLA antibody expression to multiple transplant recipients: A potential variant of the passenger lymphocyte syndrome?

“…Again it was concluded that plasma cells or a subset of memory B cells without surface ‐CD20 were producing the antibodies. Recently Koshizuka et al detected donor‐derived anti‐cytomegalovirus (CMV) antibody beyond 6 months post–lung transplantation in 2 recipients and subsequently characterized the presence of donor plasma cells (via their flow cytometry CD19 − /CD138 + profile) in the recipients’ serum.…”

“…Combined with our own report, these various case series suggest that donor lymphoid tissue originating memory cells (likely plasma cells) enter and remain in the recipient circulation long term. The case report utilizing rituximab, with no circulating B cells and the 2 case reports observing antibodies within a short 7 days from transplant, argue against the theory that B cells are the bridging cell that subsequently differentiates into plasma cells .…”

“…Several case reports describe a similar situation and timeline, and combined together offer a potential insight regarding the immune cell type responsible . Maxfield et al described 2 nonsensitized renal transplant recipients who developed third‐party anti‐HLA antibodies at 7 days that matched the sensitized donor profile and lasted beyond 3 months .…”

“…The clinical relevance of demonstrating the donor's specific profile of anti‐HLA antibodies in recipient sera include the following: It confuses and interferes with the actual recipient DSA result, potentially convincing the clinician not to act, “as it's all nonspecific.” There may be less confusion if donors with sensitizing events are screened for anti‐HLA antibodies at the outset. They are potentially a source of alloreactive antibodies, because there are studies showing poorer outcomes compared to the presence of no anti‐HLA antibodies at all . This may be particularly relevant to pediatric recipients where the aim is to achieve a very long‐lasting allograft, and retransplantation may be necessary at some point. Recognizing that donor B cells can be present in the recipients making a range of antibodies (against HLA, cytomegalovirus, hepatitis C, platelets etc), could this extend to the interpretation of other serological tests, including those of CMV, Epstein Barr virus, or other antigens? …”

Transmitted Donor Immunology Not Infection: Common Persistence of Donor Hepatitis C Antibody Production in Aviremic Lung Transplant Recipients

“…Our experience, as outlined below, confirmed patient safety in terms of infectious outcomes, despite our recipients themselves also becoming HCVAb+/NAT-. Parallel work by ourselves and others raise the possibility the observed results may be a version of the Passenger Lymphocyte Syndrome (PLS); rather than an actual recipient infection [3][4][5]. The PLS is an immunological phenomenon defined by the transmission to the recipient of viable donor B lymphocytes.…”