Cyclophosphamide given systemically to rats leads to impaired wound healing, characterized by decreases in the inflammatory reaction, fibroplasia, neovascularization, reparative collagen accumulation, and wound breaking strength. In contrast, the local application of Staphylococcus aureus peptidoglycan at the time of wounding increases all of these processes in normal rats. Accordingly, we hypothesized that inoculation of S. aureus peptidoglycan into wounds of cyclophosphamide‐treated rats would ameliorate the otherwise impaired healing. Dorsal bilateral skin incisions and subcutaneous implantation of polyvinyl alcohol sponges (two on each side) were performed on male Sprague‐Dawley rats receiving either saline or cyclophosphamide (24 mg/kg) intraperitoneally at the time of operation, on postoperative days 1, 2, 3, 4 (for rats killed on postoperative day 7), and also on day 8 (for rats killed on postoperative day 14). The incisions on one side were inoculated at the time of closure with 0.2 ml of saline solution, and the incisions on the other side with 6 mg S. aureus peptidoglycan in 0.2 ml saline solution (860 µg/cm incision). The sponges were instilled with 0.1 ml saline solution on the saline solution‐instilled incision side or with S. aureus peptidoglycan 0.5 mg/sponge) in 0.1 ml saline solution on the other side. In control rats receiving saline solution intraperitoneally, incisions treated with S. aureus peptidoglycan were significantly stronger than saline solution‐treated incisions by a factor of 1.8 at 1 week (p < 0.001); at 2 weeks the increase was small and not significant. Cardiac blood leukocytes and platelets fell markedly (90%) in cyclophosphamide‐ treated rats, and there was a decrease in wound breaking strength of their saline‐treated incisions at both 7 and 14 days compared with saline solution‐treated incisions of control rats. S. aureus peptidoglycan treatment of the wounds completely prevented this effect at 7 days, and partially at 14 days. Polyvinyl alcohol sponge reparative tissue hydroxyproline, 7 days after surgery, was decreased in cyclophosphamide‐treated rats; this was completely prevented by S. aureus peptidoglycan treatment of the sponges. Histologically, the inflammatory response to the wounding, influx of macrophages and fibroblasts, angiogenesis, and collagen accumulation were all reduced at day 7 and 14 after surgery in the sponge reparative tissue of cyclophosphamide‐ treated rats; this was prevented by S. aureus peptidoglycan treatment of the sponges. In conclusion, a single local application of S. aureus peptidoglycan ameliorates cyclophosphamide‐impaired wound healing.

An antinucleoside immunofluorescence technique (ANIF) facilitated evaluation of labeling index (LI) from frozen sections of 36 upper respiratory and digestive tract squamous cancers (URDTS) from a group of 35 patients. There were 35 URDTS of the larynx, oral cavity, or pharynx and the LIs of this population ranged from 0-39.4%, (mean, 14.7%); 6% of URDTS (2 of 36) were not assessable by ANIF. The administration of nontherapeutic radioactive materials, the establishment of cell cultures, and perturbations in cell growth implicit in the removal of tumor from host prior to assessment are unnecessary in the application of this technique.

The in vivo study of cell kinetics of squamous carcinomas of the head and neck is in its infancy. One cell kinetic parameter, the labelling index (LI), the percentage of cells actively replicating DNA, was estimated in carcinomas of the oral cavity (10), larynx (6) and pharynx (5) by an histochemical immunoglobulin technique developed recently in our laboratory: the antinucleoside antibody technique (ANIP‐LI). Data from earlier experiments using autoradiography (3H‐thymidine) have established that the enzyme‐antibody and isotopic techniques are equivalent.The LI ranged from 1 to 30 with a mean of 13 in this group of tumors. The LI could not be evaluated for 14% (3/21) of the specimens. The 3 patients with tumors not suitable for ANIP‐LI had received a full course of radiotherapy and/or chemotherapy before they had entered our study. The higher the LI of the tumor, the greater the liklihood that the surgical stage would be higher than the clinical stage, most often as a result of clinically unrecognized lymph node metastasis. However, the number of tumors sampled was inadequate for a statistical trend to be identified.The potential for the LI to be useful in the formulation of improved therapeutic strategies awaits the accumulation of more data from studies currently in progress.