Regression of bovine lymphosarcoma by treatment with cell-wall skeleton of Nocardia rubra

Smart thermosensitive poloxamer hydrogels loaded with Nr-CWs for the treatment of diabetic wounds

The treatment of diabetic wound is a focus issue. At present, the Nocardia rubra cell wall skeleton (Nr-CWS) has been proved proven to promote angiogenesis and wound repair. Unfortunately, the high-glucose diabetic wound environment makes many drugs unable to be released effectively, and soon be removed. Smart thermosensitive poloxamer hydrogel (TH) is an ideal and adjustable drug delivery platform compatible with most living tissues. Here, a multifunctional composite thermosensitive hydrogel was developed. A mixture of poloxamers 407 and 188 as the gel matrix, and then it was physically mixed with Nr-CWS. The delivery vehicle not only controlled its release stably, preventing degradation in vitro, but also showed good affinity in vitro. In vivo, compared with thermosensitive poloxamer hydrogel alone or the direct use of Nr-CWS, the thermosensitive poloxamer hydrogel loaded with Nr-CWS promoted the proliferation of vascular endothelial cells effectively, resulting in increased expression of derma-related structural proteins and enhanced angiogenesis and wound healing. This study indicated that the angiogenesis and skin regeneration brought by Nr-CWS hydrogel are related to the activation of phosphatidylinositol 3 kinase and protein kinase B, Janus kinase/signal transducer and activator of transcription, and mitogen-activated protein kinase kinase/extracellular signal-regulated kinase signaling pathways.

Nocardia rubra cell wall skeleton accelerates cutaneous wound healing by enhancing macrophage activation and angiogenesis

Objective

This study was performed to investigate the effect of Nocardia rubra cell wall skeleton (N-CWS) on wound healing of full-thickness skin defects.

Methods

Two 2- × 2-cm full-thickness wounds, one on each side of the midline, were made on the back of 12 rats. One wound was covered with Vaseline gauze soaked in normal saline, whereas the other was covered with Vaseline gauze and N-CWS. Wound dressings were changed every other day from day 0 (wound creation) to day 11. Four of the 12 rats were killed on day 7, and biopsy samples were obtained for biochemical and histopathological analyses. The expression levels of CD31, CD68, and F4/80 in the tissues were examined immunohistologically. The expression of transforming growth factor (TGF)-β1 in the wound was determined by western blot.

Results

N-CWS increased the wound healing rate, reduced the complete wound healing time, and increased the expression levels of CD31, CD68, and F4/80 on day 7. The TGF-β1 expression level in the wound was significantly higher in the N-CWS group than in the control group on day 7.

Conclusions

N-CWS can activate macrophages, increase TGF-β1 expression, and enhance angiogenesis and thus accelerate cutaneous wound healing.

In vitro activation of bovine macrophage and peripheral blood mononuclear cells by Nocardia rubra cell wall skeleton (N-CWS)

Nocardia rubra cell wall skeleton (N-CWS) was used for immunotherapy to bovine leukemia virus (BLV)-positive cattle with enlarged subcutaneous lymphatic nodules. Electron microscopical observations showed the infiltration of macrophage and T cells around N-CWS treated lesions. Antitumor effect induced by N-CWS was examined in vitro. The maximum cytolytic activity of macrophage was observed, when the cells were incubated with 10 micrograms/ml of N-CWS. Chemiluminescence response of peripheral blood mononuclear cells (PBMC) using N-CWS as stimulant was observed with a high level of activity for a long period, 5 hr. Mitogenic effect of N-CWS to PBMC was observed in the presence of macrophages but not without macrophages. Furthermore, interleukin 2 activity was recognized in supernatant of PBMC cultured with N-CWS. Maximum cytotoxic T lymphocyte response was induced when PBMC were cultured with 0.1 micrograms/ml of N-CWS.