Cellular immune response of a varicella vaccine following simultaneous DTaP and VZV vaccination

Background: Chickenpox and tester are an important cause of morbidity among children and adults. The ability of a new, thermostable vaccine to induce varicella-zoster-virus (VZV)-specific humoral and cell mediated immunity wh en given simultaneously with diphtheria-tetanus-acellular pertussis vaccine (DTaP) as a booster dose in the second year of life was investigated. Meth ods: A new, temperature stable varicella vaccine (OKA-strain, SB-Biological s, Rixensart, Belgium) was given simultaneously with a booster dose of DTaP vaccine. VZV-specific humoral and cell-mediated immunity was studied in th e first 27 out of 232 vaccinated children at 16-28 months of age, from bloo d samples drawn just before and six weeks after vaccination. VZV-specific a ntibody response, T-cell proliferation, cytokine production and expression of activation markers (CD25. HLADR) on T-cells were analyzed. Results: Vacc ination resulted in a significant rise of VZV-specific serum Ige titers and in a strong VZV-specific T-cell response in all vaccinated infants. Analys is of the expression of activation marker revealed activation of both CD4()-T-helper- and CD8(+)-T-cells. Conclusions: The varicella vaccine given si multaneously with DTaP produced strong B- and T-cell responses alike. This is the first report to show that CMI to VZV is conferred to young children by vaccination with a temperature stable VZV vaccine. (C) 1999 Elsevier Sci ence Ltd. All rights reserved.