concanavalin-a and Wounds--Penetrating

Most chronic wounds are covered by biofilms. However, questions remain about whether biofilms are a causative factor in delayed wound healing and whether the biofilm state contributes to this pathology. The purpose of this study was to develop an experimental model for convenient observation of biofilm formation on skin wounds. Full-thickness wounds were created on the backs of SD rats. Suspensions of Pseudomonas aeruginosa carrying the gene encoding green fluorescent protein were then applied to the wounds. The wounds were harvested at 8 h, and at 1, 3 and 7 days postwounding for histological and immunohistochemical examinations. Fluorescence microscopy confirmed the presence of a biofilm as early as 8 h. Comparing with non-infected wounds, epithelialization was not delayed. In conclusion, wound healing of rat acute wounds was unaffected by biofilm formation.

Topics: Alginates; Animals; Biofilms; Concanavalin A; Disease Models, Animal; Glucuronic Acid; Green Fluorescent Proteins; Hexuronic Acids; Male; Pseudomonas aeruginosa; Rats; Rats, Sprague-Dawley; Wound Healing; Wounds, Penetrating

It has been hypothesized that there are differences between membrane-associated glycoconjugates of wounded (migrating) epithelium and those of nonwounded (stationary) epithelium. To test this hypothesis, wheat germ agglutinin-ferritin (WGA-Fe) and concanaval in A-ferritin (Con A-Fe) binding to apical membranes of wounded and nonwounded rabbit corneal epithelia were compared. Epithelial abrasions of the superior half of the cornea were allowed to heal in vivo for six hours. Fixed corneas were then incubated with lectin-ferritin and prepared for electron microscopy. Measurements (ferritin particles per linear um of membrane) of WGA-Fe indicated that binding to leading cells (40.7 particles/um), to areas 20 to 35 cells behind the leading edge (46.5 particles/um) and to nonwounded epithelium (45.1 particles/um) from contralateral eyes were not significantly different. A competitive inhibitor of WGA, 0.2M N-acetylglucosamine, however, blocked 94 percent of WGA binding on leading cells (2.3 particles/um), while binding persisted in areas behind the leading edge (39.5 particles/um) and on nonwounded epithelium (43.6 particles/um). This indicates that leading cell surfaces have a weak affinity for WGA. Unlike WGA, Con A showed a distinct preference for leading-edge cells (33.9 particles/um) compared to nonwounded epithelium (9 particles/um). In areas 20-35 cells behind the leading edge, Con A binding was intermediate to these two extremes.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Acetylglucosaminidase; Animals; Cell Movement; Concanavalin A; Cornea; Corneal Injuries; Epithelium; Glycoproteins; Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; Rabbits; Wheat Germ Agglutinins; Wound Healing; Wounds, Penetrating