[Fibronectin binding to Staphylococcus aureus in experimental staphylococcal skin infection in mice]

Staphylococcus aureus infection of skin was produced in cyclophosphamide-treated mice by intracutaneous inoculation of a strain in this organism clinically isolated from a carbuncle. Deposition and binding of fibronectin in initial stage of the infection were followed by immunohistochemistry and immunoelectron microscopy. Fibronectin began to deposit in a fine granular pattern in the dermis and musculocutaneous layer at 2 minutes after the inoculation and gradually increased with time. Fibronectin binding on the surface of staphylococcal cells was seen after 12 hours of inoculation. At 24 hours two patterns of binding were seen. In one pattern, fibronectin was bound to a part of the cell surface of the microorganisms. The fibronectin binding parts were seen very close or attached to the fibrin-like-structure and dermal connective tissues. This suggests that fibronectin helped staphylococcus cells to attach to fibrin or connective tissues. The other pattern of fibronectin binding was the binding of fibronectin all around the cells. This pattern could be interpreted as inhibition by fibronectin of staphylococcus attachment to the fibrins and the tissues.