The Effect of Hybridoma Antibody Administration upon Neutrophil Kinetics during Experimental Type III Group B Streptococcal Sepsis

Lung Antimicrobial Defenses in the Newborn

“…30 In experimental animals provision of monoclonal anti-group B streptococcal antibody protects against lethal neonatal group B streptococcal lung infection. 31 This is mediated in part by effective recruitment of granulocytes to the lungs of antibody recipients. 31…”

“…31 This is mediated in part by effective recruitment of granulocytes to the lungs of antibody recipients. 31…”

“…12,[33][34][35] Lung clearance of S. aureaus and group B streptococci is impaired in 1-day old rabbits and rats. 31,36,37 This appears to reflect the inadequacy of local defenses, including alveolar macrophages. 36,37 In newborn animals challenged with moderate numbers of bacteria, the recruited phagocyte response is also easily overwhelmed, particularly in animals that lack specific antibody.…”

Group B Streptococcal Infections

“…The nearly maximal proliferative rate of granulocytic stem cells in noninfected neonatal animals led to the suggestion that neutrophil transfusion might improve the survival of human neonates with group B streptococcal infection in whom neutrophil storage pool depletion was documented [278,378]. In experimental infection with type III GBS, monoclonal IgM antibody to type III polysaccharide stimulated the release of neutrophils from storage pools into the bloodstream and improved neutrophil migration to the site of infection [387]. This facilitation of neutrophil function by type III-specific antibody improved survival in animals only if the antibody was administered when neutrophil reserves were intact (very early in infection) [388].…”

Treatment of Experimental Group B Streptococcal Infection with Hybridoma Antibody

“…We have previously shown that when type-specific IgM antibody, prepared from hybridoma cell lines, was administered to neonatal animals together with bacteria, the mortality rate decreased from 90% to zero (5). In addition, our previous work demonstrated an important interaction between antibody and the neutrophil system: antibody facilitates rapid release of neutrophils from storage and enhances the efficiency of neutrophil migration toward the site of infection (5). Therefore, antibody may require an intact neutrophil supply for its protective action.…”