Abstract
The enzymic activity of Trichophyton rubrum has been investigated in relation to the plasma-dependent chemotaxis of polymorphonuclear leucocytes (PMNs). In Boyden-type experiments use of a cytoplasmic extract of T. rubrum (CETr) produces neutrophil chemotactic factor (NCF) from plasma. CETr was shown to have activity for eight enzymes: heat treatment of CETr led to a partial loss of activity for seven enzymes and a significant reduction in the number of PMNs migrating. Addition of CETr to plasma and incubation for 18 h at 37°C before use led to complete loss of chemotactic activity. The similar incubation of plasma with trypsin led to a complete loss of chemotactic activity. CETr has greater activity than trypsin in the production of NCF from plasma. The results are discussed in relation to reports on the importance of serine esterases in PMN chemotaxis. The failure of PMNs to migrate into keratinized tissue infected with T. rubrum is noted and it is suggested that the high enzymic activities necessary for the colonization of keratinized tissue effect a breakdown of NCF.