Gamma interferon levels among Bangladeshi children after measles vaccination

Gamma interferon (IFN-γ) plays an important role in the immune response to live measles virus vaccination. To study the immune response to measles vaccination, IFN-γ level was estimated in 30 children. Of these, 24 children vaccinated with a single dose of measles vaccine at nine months of age and 06 children vaccinated with a second dose during the Measles Catch-up Immunization campaign. Measles vaccine strain was cultured in Vero cell line and the Tissue Culture Infective Dose (TCID)50 was used as standard live virus. Peripheral blood Mononuclear cells (PBMCs) was separated by Ficoll-Hypaque density gradient centrifugation and stimulated with measles virus antigens and mitogens (lectin), cultured in CO2 and iFN-γ level was measured from culture supernatant by ELISA. On stimulation with measles antigen and lectin respectively, IFN-γ level was highest (105 pg/ml and 226.54 pg/ml) in the 109-120 months age group while it was lowest (12.97 ± 8.16 pg/ml and 13.16 ± 8.0 pg/ml) in the 61-72 months age group. No significant difference was observed in IFN-γ level after stimulation with either measles antigen or lectin among well-nourished (p < 0.8) and mal-nourished (p < 0.7) children suggesting that nutritional status did not have any effect on IFN-γ level. However, IFN-γ level was higher in children who received two dose of measles vaccine than those who received a single dose (p < 0.001).