Do Sex Differences in Respiratory Burst Enzyme Activities Exist in Human Immunodeficiency Virus-1 Infection?

Studies have shown that human immunodeficiency virus type 1 (HIV-1) disproportionally affects more females than males. Affected individuals are susceptible to infections due to depressed immunity, qualitative defects in phagocytic function and altered phagocytosis as well as lowered oxidative burst capacity. This study seeks to determine whether sex differences exist in serum activities of respiratory burst enzymes in HIV-1–infected female and male subjects. Serum myeloperoxidase, catalase and superoxide dismutase activities were assayed in 170 confirmed HIV-1 positive and 50 HIV-1 negative subjects using ELISA. Data were analyzed using Student’s t-test and p values of less than 0.05 were considered significant. The measured enzyme activities were significantly higher (p < 0.001) in females than males in HIV-1 negative subjects while no sex differences were observed in HIV-1 positive subjects. The absence of sex differences in the activities of respiratory burst enzymes in HIV-1 infection may be due to immune activation as a result of active phagocytic leukocytes, immune reactivity and inflammation.