Accelerated tissue repair induced by micrococcus varians.

The present investigation was undertaken to study the effect of inoculated Micrococcus varians organisms on developing granulation tissue in rats. Subcutaneously implanted hollow cylindrical cellulose sponges were used as an inductive matrix for the growth of granulation tissue. The control implants were injected immediately after implantation with 1 milliliter of physiologic saline solution while the experimental implants were injected with a corresponding volume of saline solution containing live micrococci 10(7) microorganisms per milliliter. Cytologic and bacteriologic analyses of wound fluid aspirated from the central dead space of the implants were carried out three, seven and 14 days after implantation. Local blood flow and albumin extravasation were measured on day seven and granulation tissue grown into the implants was analyzed chemically on days seven and 14. No macroscopic infection with pus formation occurred, while Micrococcus varians was cultured from each inoculated implant. In the inoculated implants, the number of wound fluid neutrophils, granulation tissue blood flow and albumin extravasation increased significantly above the control level. Correspondingly, the amounts of granulation tissue deoxyribonucleic acid, nitrogen, collagen hydroxyproline, hexosamines and uronic acids in the inoculated implants exceeded significantly the control value on both days seven and 14. To conclude, inoculation of experimental wounds with nonpathogenic Micrococcus varians organisms enhanced local inflammatory reaction and blood flow, and promoted granulation tissue formation.