Cytotoxic activity against varicella-zoster virus-infected target cells after marrow transplantation

Cytotoxic activity by peripheral blood lymphocytes against varicella-zoster virus (VZV) infected matched and mis-matched fibroblasts and K562 targets was studied in 17 allogeneic marrow transplant recipients during the first 100 days after transplantation. Lysis of HLA mis-matched VZV infected target cells by patient's lymphocytes was significantly reduced after transplant compared to healthy normals (p less than 0.05). In contrast, lysis of K562 targets by peripheral blood lymphocytes from patients was similar or increased compared to controls. Three patients developed herpes zoster during the study. No significant difference was found in the lysis of VZV infected mis-matched target cells between patients who developed herpes zoster compared to those patients who did not. With the exception of in one patient shortly after the occurrence of herpes zoster, no HLA-restricted lysis could be detected. Depressed natural killer cell activity against VZV infected targets might be important for the development and outcome of VZV infection but studies in more patients and with longer follow-up time are needed.