Antibody responses to vaccinations given within the first two years after transplant are similar between autologous peripheral blood stem cell and bone marrow transplant recipients

As a consequence of the significantly larger inoculum of lymphoid cells pre sent in peripheral blood stem cell (PBSC) harvests compared to bone marrow (BM), it is possible that autoPBSCT recipients may have an earlier and/or e nhanced response to vaccines. Until data to confirm this become available, the European Blood and Marrow Transplantation Association (EBMT) recommend that all transplant recipients be immunized in the same way regardless of s tem cell source. We performed a prospective study comparing serological res ponses to influenza, pneumococcal polysaccharide and tetanus toxoid vaccine s between autoPBSCT with autoBMT recipients. Antibody responses in sibling HLA-matched allogeneic BMT (alloBMT) survivors were also evaluated. All vac cines were administered within the first 2 years after stem cell transplant ation. Fifty patients were enrolled. The time of vaccination after transpla nt was similar between autoPBSCT (mean 11 months for each vaccine) and auto BMT recipients (mean 12 months except 13 months for tetanus toxoid) (P = NS ). Serological responses were poor and no significant difference in respons e to any of the vaccines used was seen between the three transplant cohorts . We provide no evidence that current EBMT guidelines be modified. Large pr ospective vaccine studies are needed to address the issue more fully.