Cellular response in humans following vaccination with gripax influenza virus

Cellular response of peripheral blood lymphocytes to influenza antigens was measured in a group of young nurse‐student volunteers (17–24 years old), following vaccination with a formol‐inactivated trivalent influenza vaccine (Gripax). Cord blood lymphocytes (controls) did not react with any of the antigens. This excluded the possibility of any nonspecific mitogenicity of viral antigens. Viability of the cells was indicated by their responsiveness to phytohemagglutinin (PHA). Prior to immunization antigenic recognition to circulating strains (A/England (H₃N₂) and B/Hong Kong) was found in about 44% of the vaccinees; recognition of the recent strain A/USSR (H₁N₁) was found in only 10.5%. Following vaccination, approximately 80% of the subjects exhibited cellular response to all three vaccine strains. This includes the negative subjects, who showed an approximate 70% rate of conversion. There was no correlation between the antibody state and cellular response prior to and following vaccination as gathered from matched data of each participant.