Immunologic correlates of protection against rotavirus challenge after intramuscular immunization of mice

The capacity of intramuscular (i.m.) inoculation of mice with homologous or heterologous host rotaviruses to induce protection from challenge was evaluated, i.m. inoculation with live, wild-type rotavirus (murine strain EDIM) induced complete protection from viral shedding after challenge for at least 6 weeks after inoculation; protection was correlated with production of virus-specific immunoglobulin A (IgA) by lamina propria (LP) lymphocytes. i.m. inoculation with inactivated EDIM, cell culture-adapted EDIM, or simian strain RRV was associated with partial protection, characterized by reduced viral shedding after challenge, Partial protection after challenge was not associated with production of virus-specific IgA by LP lymphocytes, The mechanisms by which i.m. inoculation induces virus-specific humoral immune responses in the small intestinal LP were examined.