Use of Multivariate Immune Reconstitution Patterns to Describe Immune Reconstitution after Allogeneic Stem Cell Transplantation in Children.

Immune reconstitution after hematopoietic stem cell transplantation (HSCT) is a complex process. Impacts of the reconstitution of different immune cells over time are complex and difficult to understand. New mathematical models are needed to better understand this process. In this study, we used principal component analysis to better analyze the process of immune reconstitution after HSCT. Forty-six consecutive patients receiving HSCT for malignant and nonmalignant disorders were included in the study. All patients were followed for at least 24 months after transplantation with regular blood sampling for analysis of lymphocyte subset numbers and function. Exponentially transformed lymphocyte subset counts and lymphocyte functional markers were analyzed to identify major trends in the reconstitution process. Using our multivariate model for mapping immune reconstitution after HSCT, we showed that dysfunctional reconstitution patterns precede severe complications, such as chronic graft-versus-host disease, relapse, and death.