Collagen membrane alleviates peritendinous adhesion in the rat Achilles tendon injury model.

BACKGROUND: Tendon adhesion is one of the most common causes of disability following tendon surgery. Therefore, prevention of peritendinous adhesion after surgical repair of tendon is a major challenge. The aim of this study was to explore the possible application of a collagen membrane for the prevention or attenuation of peritendinous adhesions. METHODS: Sprague-Dawley (SD) rat Achilles tendon was cut and sutured by a modified Kessler's technique with or without the collagen membrane wrapped. Macroscopic, morphological and biomechanical evaluations were applied to examine the recovery of the injured tendon at 4 and 8 weeks after surgery. RESULTS: The surgery group wrapped by collagen membranes had a better outcome than the group with surgery repair only. In the collagen membrane-treated group, less adhesion appeared, stronger tensile strength was detected, and more tendon fibers and collagen I expression were observed morphologically. CONCLUSION: Wrapping the tendon with a collagen membrane may be an efficient approach for tendon repair and preventing tendon adhesion after its ruptures.

[Effects of novel human chemokine-like factor superfamily 8 on proliferation and EGFR expression of HL-60 cells].

This study was aimed to investigate the effect of chemokine-like factor superfamily 8 (CKLFSF8) on proliferation and expression of epidermal growth factor receptor (EGFR) of HL-60 cells. Expression of CKLFSF8 mRNA on HL-60 cell line was assayed by RT-PCR; the target gene was transfected into the cells by lipid vector, cell proliferation was determined by MTT assay, while expression of EGFR in HL-60 was determined by immunocytochemical technique. The results indicated that expression of CKLFSF8 existed in HL-60 cells. After transfection, cell proliferation was inhibited (P < 0.05) and the expression of EGFR in HL-60 cells was also discovered to be inhibited (P < 0.05). It is concluded that the proliferation and expression of EGFR in HL-60 cells can be inhibited by transfection of CKLFSF8. The novel chemokine may provide a new approach in the treatment of leukemia.

[Production of specific CTL induced by exosomes derived from K562 cells].

The aim of this study was to investigate whether exosomes derived from K562 cells and human monocyte-derived dendritic cells (DCs) transfected with total RNA of K562 cells are capable of inducing antigen-specific cytotoxic T lymphocytes (CTL) responses in vitro. DCs were generated from peripheral blood mononuclear cells (PBMNC) of healthy volunteers in the presence of GM-CSF and IL-4, and then were transfected with K562 RNA by using DOTAP lipofection. Exosomes was extracted from the supernatant of DCs and K562 cells. The T cell were activated to be tumor specific CTL after DCs and exosomes were co-cultured with autologous T cells derived from healthy volunteers' PBMNC. The effect of CTL on K562 cells was detected by MTT assay. The results showed that treatment of T cells with exosomes derived from K562 cells or DCs transfected with total RNA of K562 cells could significantly promote their killing ability on K562 cells as compared with untreated T cells (P < 0.05). The killing ability of T cells treated with exosomes on K562 cells was stronger than on HL-60 cells (P < 0.05). It is concluded that the specific CTL immune response to leukemia cells can be induced by exosomes derived from K562 cells.