Local and Systemic Opsonic Adherent, Hemagglutinating and Rosette Forming Activity in Mice induced by Respiratory Immunization with Sheep Red Blood Cells

The humoral response in mice after intranasal (IN) instillation of sheep red blood cells (SRBC) was compared to that produced by intraperitoneal route of immunization. Study of opsonic adherent (passive indirect cytophilic) and hemagglutinating antibody levels in serum and bronchial washings after repeated challenge with SRBC showed that serum antibody titers following respiratory immunization does not differ from the general patterns of a humoral antibody response. The bronchial wash antibody titer was higher than the serum titer as calculated per globulin unit. In contrast, the appearance of measurable antibodies in the bronchial washings after repeated intraperitoneal immunization was delayed and in low titer. B. pertussis vaccine administered in conjunction with SRBC was found to be an excellent adjuvant in the intranasal route of immunization. A single administration of SRBC-Pertussis evoked a considerable adjuvant effect as measured by hemagglutinating and opsonic adherent tests. Monospecific anti-mouse IgG nullified the hemagglutinating and opsonic adherent activity of the bronchial washings, while monospecific anti-mouse IgM had no effect in either activity.

Lung and spleen cells capable of forming rosettes with SRBC of intranasally immunized and control mice were counted. Mean response on day 14 was 6 × 10³ rosettes per million lung lymphoid cells in comparison with less than 10³ in control mice. No difference was found in the number of rosette-forming cells in the spleen of control and intranasally immunized mice.