The Journal of Medical Microbiology, Vol 24, Issue 3 187-196, Copyright © 1987 by Society for General Microbiology
Properties of equine anti-lipopolysaccharide hyperimmune plasma: binding to lipopolysaccharide and bactericidal activity against gram-negative bacteria
M. T. Wells, S. L. Gaffin, M. Gregory and Y. Coovadia
Department of Physiology, University of Natal Medical School, Durban, South Africa.
Anti-lipopolysaccharide equine hyperimmune plasma (anti-LPS), which has
been used successfully to treat LPS (endotoxin)-mediated disorders, has
been further characterised. IgG present in anti-LPS had the highest
affinity for LPS prepared from Salmonella typhimurium, S. typhi, S. abortus
equi and Shigella flexneri and intermediate affinity for Escherichia coli
O55:B5, E. coli O127:B8 and S. enteritidis. Anti-LPS destroyed by means of
complement activation a wide range of gram-negative bacteria, including
various species and strains of Klebsiella, Enterobacter, E. coli, Sh.
flexneri, Providencia, Salmonella and Pseudomonas. Control plasmas or
saline had little or no effect. Maximum killing occurred within seconds to
minutes. Electronmicroscopy showed that anti-LPS treatment of K. pneumoniae
caused extensive cell wall and cytoplastic membrane disruption, followed by
the appearance of spheroplasts and cell ghosts. Antibodies were required in
100,000-fold excess to inhibit the limulus amoebocyte lysate reaction with
LPS from E. coli. Anti-LPS thus contains IgG that binds to a wide range of
LPS, and can destroy a wide range of gram-negative bacteria by means of
complement activation.
