[Secondary immune response of mice immunized with a protein-cellulose complex].

It has been previously established that an intravenous injection of a protein antigen solution into mice primed with the same antigen in the form of a protein-cellulose complex induces an intensive antibody production (up to 10,000 antibody-forming cells/10(6) splenocytes and up to 3 mg of antibodies/ml of serum). The present study has shown that secondary immune response can be considerably enhanced if large amounts of the antigen are administered intraperitoneally in a protein-cellulose complex during secondary immunization. In these experiments the mean number of antibody-forming cells was 50.

Induction of abundant antibody formation with a protein-cellulose complex in mice.

A method is described for immunizing mice with a protein-cellulose complex obtained by covalent coupling of antigenic protein molecules to suspended cellulose particles. Primary immunization of the animals with the complex led to a pronounced immune response persisting for 20-30 days. Subsequent administration of the same antigen in a soluble form resulted in extremely active antibody formation equal to or better than that induced with Freund's complete adjuvant.

[Use of a protein-cellulose complex for inducing intensive antibody formation in mice].

The protein-cellulose complex prepared by covalent immobilization of single protein molecules on insoluble cellulose particles was used for priming C57BL/6 and BALB/c mice. The serum antibody content and the number of spleen AFC were assayed after animals' boosting with the soluble protein. Such a complex was shown to have marked advantages over the same protein injected both in complete Freund's adjuvant and in a soluble form, in particular.

[Effect of Fab-fragments of antibodies against spleen cell surface antigens on the development of antibody formation in cultures of different densities].

The role of surface antigens in the density-dependent inhibition of primary immune response in mouse spleen cell cultures was investigated. For this purpose Fab-fragments of rabbit IgG obtained after immunization with mouse splenocytes were used. Such Fab-fragments alone had no effect on immune response in both optimal and dense cultures.

[Antigen-induced increase in the number of cells producing non-specific immunoglobulins].

The appearance of antibody- and nonspecific immunoglobulin-forming cells (AFC and nIFC) in spleen cell suspensions from normal mice and from those immunized with sheep red blood cells (SRBC) was studied. The cell suspensions were cultivated in the modified Mishell-Dutton system. The induction of the immune response in vitro resulted in a sharp increase of nIFC formation.