Date of Award

3-2-1991

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry

Abstract

This laboratory has observed significantly different survival rates for male balb/c mice maintained on different diets following infection with herpes simplex virus type I (HSV). The two diets, presumably nutritionally complete, are Purina, an undefined laboratory chow, and Teklad, a defined zinc control diet. This investigation examined the effect of these diets on the production of interferon, anti-HSV antibodies and peritoneal macrophage activity. Animals maintained for five weeks on each of the diets remained healthy, and no visible differences were apparent. Food intake and growth rates were equivalent for the diet groups. The concentration of virus in various organs was higher in Purina-fed mice, measuring a 3-fold difference in peak titers between the diet groups. Highest titers were present in the central nervous system, brain and spinal cord, and may indicate that encephalitis leads to higher death rates for Purina animals. As determined by an infectious center assay, cultured adherent peritoneal cells from Teklad-fed animals inhibited viral replication more than macrophages from Purina-fed animals. Teklad macrophages were more efficient at phagocytizing latex beads. Animals on the Teklad diet produced significantly higher interferon levels in plasma, spleen and cultured macrophage samples when stimulated by polyinosinic-polycytidylic acid or inactive HSV. The interferon produced was predominantly type I and probably of macrophage origin. Antibody titers were equivalent for the animal groups after immunization with inactive HSV.We conclude that early, non-specific immune responses are significantly different in mice maintained on these two diets. The macrophage would seem to be important for ingestion of virus, inhibition of replication and interferon production, such responses being enhanced by the control diet. Humoral responses did not account for disparate survival rates.

Download

Share

COinS