Cell invasiveness of Proteus mirabilis and Proteus vulgaris strains.

Cell penetration ability of haemolytic and non haemolytic Proteus rods was compared. Among four Proteus strains all were able to invade the tested cells (Vero 135, HeLa, L-929 and human blood lymphocytes) but the expression of this feature by haemolytic strains was markedly higher. The survival and multiplication of intracellular bacteria, especially in the case of fresh human blood lymphocytes may be of importance for the development of infection in higher organisms.