Abstract
The phagocytosis by human polymorphonuclear leucocytes of 37 bacterial strains identified as Streptococcus milleri (10 strains), strictly anaerobic gram-positive cocci (10) Prevotella intermedia (6), Pr. oralis (5) and Fusobacterium nucleatum (6) was investigated in vitro. The ingestion of S. milleri and strictly anaerobic gram-positive cocci was significantly greater (p < 0.001) than that of strains of Prevotella spp. and F. nucleatum. The degree of uptake of capsulate and non-capsulate strains did not differ.