INFLUENCE OF CHAIN-LENGTH OF N-ACETYL-D-GLUCOSAMINE AND D-GLUCOSAMINERESIDUES ON DIRECT AND COMPLEMENT-MEDIATED CHEMOTACTIC ACTIVITIES FORCANINE POLYMORPHONUCLEAR CELLS

The direct and complement-mediated chemotactic activities (CA) of N-ac etyl-D-glucosamine (GlcNAc), D-glucosamine (GlcN), GlcNAc and GlcN oli gomers, chitin and chitosan for canine polymorphonuclear cells (PMNs) were investigated in vitro. GlcNAc6 and GlcN5 similar to 6 provided th e most effective stimulation of CA, with GlcN6 having a seven-fold str onger effect than GlcNAc6. Serum incubated with chitin and chitosan (3 7 degrees C, 30min) had a similar CA to that of zymosan. The total com plement activity (CH50) of serum mixed with chitin and chitosan was lo wer than control level, but monomers and oligomers of GlcNAc or GlcN d id not decrease complement activity. Subcutaneous injection of GlcN6 a nd chitosan enhanced more PMN migration than GlcNAc6 and chitin in viv o. It was demonstrated that GlcN residues induced higher direct CA tha n GlcNAc residues, while complement-mediated CA was only induced by ch itin and chitosan, but not by GlcNAc, GlcN and their oligomers. (C) 19 97 Elsevier Science Ltd.