Elevated antibody response by antigen presentation in immune complexes

Active immunization techniques against exogenous source antigens (ags - such as bacteria, virus) proved to be successful in preventing many acute infectious diseases from occurring in a susceptible population. However, an active immunization technique that could be employed both prophylactically and therapeutically has so far not been described. We have developed a new vaccination technique that employs specific immune complex (IC) containing components which is able to redirect immune-response outcomes in both preventative and curative regimens in an experimental autoimmune kidney disease. The technique with appropriate modifications was assessed using an exogenous ag in our present experiment.

We prepared an exogenous ag on a HiTrap affinity column and injected it by five different vaccination techniques into rats. Antibody (ab) responses against the ag were evaluated by ELISA. Statistical analysis assessed possible significant differences in ab responses.

The most powerful immune response was initiated following intraperitoneal (IP) injections of normal rabbit immunoglobulin G (nRIgG) in Freund's complete adjuvant (FCA). The second most powerful immune response was evoked when the same ag (nRIgG) was injected in the form of IC at ag excess.

1. Induction of a powerful ab response, without the use of an adjuvant, can be achieved in rats injected with ICs. 2. IC is non-toxic, non-irritant, and able to initiate the production of the same class of immunoglobulin with the same specificity/function that resides in the inoculum.