Donor cell chimerism evaluation in cerebrospinal fluid by short tandem repeat analysis following allogeneic hematopoietic stem cell transplantation

Cerebrospinal fluid (CSF) cell count, morphology and flow cytometric evaluations are used to investigate central nervous system (CNS) involvement in leukemia/lymphoma. We performed CSF short tandem repeat (STR) analysis to monitor CSF chimerism status and evaluate for disease involvement in 11 asymptomatic pediatric allogeneic hematopoietic stem cell transplantation (HSCT) recipients with hemato-lymphoid neoplasms and high risk for or history of CNS involvement. Eighteen (64%) of the samples with median CSF cell count of 1/mm3 with 90% lymphocytes gave conclusive STR results, suggesting that this DNA-based method can be used in monitoring CSF chimerism status after HSCT with an acceptable yield.