Polyclonal lymphocyte activators: adjuvant activity of a crude extract of Streptococcus faecium

A crude extract of Streptococcus faecium, prepared according to Krämer and Bradis method, was utilized to further extend our previous research on polyclonal lymphocyte activators. Experiments were performed using Jerne's PFC method on 12 week-old C3H/FeJ mice immunized with sheep red blood cells to study the adjuvant activity of the crude extract by varying its dose, times of administration, and administration route (intraperitoneal, intravenous, subcutaneous). The extract, containing cell membranes and cytoplasmic fraction, was demonstrated to have adjuvant activity which depend on the dose and time of administration.