Changes in intracellular cytokine levels in newborn and adult lymphocytes induced by HSV-1.

Changes in the expression of intracellular interleukin-2 (IL-2), interleukin-4 (IL-4), interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha in newborn and adult lymphocytes induced by herpes simplex virus (HSV)-1 were examined. Cord blood mononuclear cells (CBMC) or adult peripheral blood mononuclear cells (PBMC) were infected with HSV-1 and cultured with phorbol 2-myristate 13-acetate (PMA) plus ionomycin in the presence of monensin for 4 hr. Surface antigen and intracellular cytokines were stained simultaneously and analyzed by flow cytometry. The percentage of cells that expressed IL-2, IFN-gamma, and TNF-alpha was significantly increased in HSV-1-infected CD3+, CD4+, CD8+, CD45RA+, and CD45RO+ lymphocytes compared with uninfected lymphocytes from adult PBMC. The percentage of cells that expressed IL-2 and TNF-alpha was increased significantly in HSV-1-infected CD3+, CD4+, CD8+, and CD45RA+ lymphocytes compared with uninfected lymphocytes from CBMC. IFN-gamma was under the detectable level in HSV-1-infected and uninfected lymphocytes from CBMC. Intracellular IL-4 was not detected in HSV-1 or in uninfected lymphocytes from PBMC and CBMC. These results demonstrate that HSV-1 enhances intracellular levels of IL-2, IFN-gamma, and TNF-alpha in adult lymphocytes and defective IFN-gamma production in cord blood.