2019 Volume 56 Issue 1 Pages 32-39
After hematopoietic stem cell transplantation, vaccination is recommended to prevent infection, but there have been few reports on factors affecting the effect of live vaccines. In this study, we examined the immunological competence at the time of vaccination after hematopoietic stem cell transplantation and antibody titer after immunization. The seropositivity percentages were 75% for measles, 50% for rubella, 40% for varicella, and 18.2% for mumps. Stimulation index (S.I.) values determined by the phytohemagglutinin (PHA) lymphocyte transformation test were significantly higher in the vaccine-high-efficacy group, which showed antibody positivity for two or more vaccines, than in the low-efficacy group, which showed antibody positivity for one or no vaccine (p=0.028). Functional recovery of lymphocytes, particularly CD4-positive cells, is important for acquiring antibodies after vaccination. It is suggested that the SI value determined by the PHA lymphocyte transformation test could be one of the indicators for judging the time of vaccination.
