Objective: To investigate the proportional changes of CD4(+)CD25(+) regulatory T cells in peripheral blood after lymphocyte therapy in unexplained recurrent spontaneous abortion (URSA) patients.
Design: Prospective cohort study.
Setting: University Hospital.
Patient(s): Twenty-five URSA patients.
Intervention(s): Measurements of CD4(+)CD25(+) regulatory T cells in peripheral blood before and after paternal or third-party lymphocyte immunization.
Main outcome measure(s): The proportion of CD4(+)CD25(bright) regulatory T cells and the percentage of CD25(bright) cells in the CD4(+) T-cell population.
Result(s): The proportion of CD4(+)CD25(bright) T cells in peripheral blood from URSA patients was increased significantly after paternal or third-party lymphocyte immunization therapy, whereas the percentage of CD4(+)CD25(dim) cells were decreased significantly. The percentage of CD4(+)CD25(bright) cells in the CD4(+) T-cell population was significantly increased, and the proportion of CD4(+)CD25(bright) T cells was significantly higher in successfully pregnant women than in those with pregnancy loss after lymphocyte therapy.
Conclusion(s): Allogeneic lymphocyte therapy can enhance the percentage of CD4(+)CD25(bright) regulatory T cells in peripheral blood, therefore CD4(+)CD25(+) regulatory T cells may serve as a novel biomarker for monitoring allogeneic lymphocyte therapy in URSA patients.