The interaction of leukocytes and their hydrolases with bacteria in vitro and in vivo: the modification of the bactericidal and bacteriolytic reactions by cationic and anionic macromolecular substances and by anti-inflammatory agents.

Acid hydrolases from extracts of human blood leucocytes lyse Staph.aureus, Staph.albus and Strep.faecalis in vitro. The leucocyte enzymes can be substituted by a lytic mixture which contains crude trypsin, lysolecithin, phospholipase C and lysozyme, which lyse other bacterial species, e.g. E.coli and Listeria which are resistant to leucocyte enzymes. Bacteriolysis by the lytic agents is strongly inhibited by the anionic polyelectrolytes, heparin, chondroitin sulphate, DNA, dextran sulphate and other sulphated mucopolysaccharides, by the cationic materials, histone, protamine sulphate, leucocyte cationic proteins and polylysine. Other strong inhibitors are trypsan blue and congo red, the phospholipids phosphatidyl serine and ethanolamine, gold thiomalate, extracts of coffee and tea and the anti-inflammatory agents, ultracorten-H, and ultracortenol. Bacteriolysis is also strongly inhibited by normal human serum and by synovial fluids from patients with a variety of joint diseases. The inhibitors in these body fluids are associated with the globulin fractions. Since mixtures of anionic and cationic polyelectrolytes, at equimolar concentrations, failed to inhibit bacteriolysis by leucocyte enzymes, it is postulated that a delicate balance between positively and negatively charged inhibitors control the degradation of cell wall components of bacteria in inflamed areas. Such bacterial components, induce 'storage type' granulomas. The possible role played by polyelectrolytes in the control of the inflammatory process induced by leucocyte hydrolases will be discussed.