Abstract
Mild hydrolysis of Haemophilus influenzae type a lipopolysaccharide by ion exchangers in the presence of chloroform, to remove the lipid moiety, yielded a nontoxic and immunogenic polysaccharide fraction. This polysaccharide selectively triggered murine B lymphocytes in vitro: (i) it induced enhancement of thymidine incorporation and stimulated antibody secretion in cultures of normal and nude mouse spleen cells; (ii) it did not stimulate splenic T lymphocytes; (iii) the activation of B lymphocytes was not absolutely dependent on the presence of macrophages. Sepharose 4B gel filtration showed that this polysaccharide consisted at least of two fractions: PS I (molecular weight [MW] 10(6)) and PS II (MW 10(4)). Only PS I was found to act as a polyclonal B cell activator. EDTA treatment dissociated the polysaccharide into PS III (MW 10(6)) and PS IV (MW 10(4)), which was not reassembled after the addition of 0.02 M CaCl2. Both fractions PS III and PS IV were unable to stimulate B lymphocytes. The immunological active fraction of H. influenzae polysaccharide is PS I. This fraction consists of a high-molecular-weight group (10(6)) and an association of 10(4)-MW aggregated units.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
