Objective:To investigate the effect of keloid fibroblasts on the polarization and expression of inflammatory factors of M0 macrophages and possible mechanisms, and provide theoretical basis for new targets for keloid therapy.Methods:Keloids, normal skin tissues and paraffin specimens from patients undergoing plastic surgery in the First Affiliated Hospital of Sun Yat-sen University from November 2020 to September 2021 were collected, and fibroblasts of keloids and normal skins were isolated and co-cultured with M0 cells formed form THP-1 by phorbol ester (PMA)-stimulation to detect the expression of macrophage polarization markers and cytokines. Besides, keloid fibroblasts were treated with exogenous tumor necrosis factor-α(TNF-α) to detect its effect on the proliferation and extracellular matrix expression.Results:Macrophages were dominated by CD163 + (M2) in keloid tissues. Moreover, M0 cells expressed more TNF-α when co-cultured with keloid fibroblasts, compared with those with normal skin fibroblasts, in which, the positive staining rates of TNF-α were 19.32% and 29.52% respectively by flow cytometry. Furthermore, the proliferation was promoted and the expression of extracellular matrix proteins (COL3A1 and FN1)and Vimentin were upregulated in keloid fibroblasts under TNF-α stimulation. However, there was no significant difference in the expression of polarization surface markers CD86 and CD163 in macrophages, when co-cultured with keloid fibroblasts or normal skin fibroblasts. Conclusions:Keloid fibroblasts promote the expression of TNF-α in macrophages, which in turn promotes the proliferation and extracellular matrix secretion of keloid fibroblasts.

Background: Due to the unavailability of an effective vaccine or antiviral drug against the African swine fever virus (ASFV), rapid diagnosis methods are needed to prevent highly contagious African swine fever. Objectives: The objective of this study was to establish the ladder-shape melting temperature isothermal amplification (LMTIA) assay for the detection of ASFV. Methods: LMTIA primers were designed with the p72 gene of ASFV as the target, and plasmid pUC57 was used to clone the gene. The LMTIA reaction system was optimized with the plasmid as the positive control, and the performance of the LMTIA assay was compared with that of the commercial real-time polymerase chain reaction (PCR) kit in terms of sensitivity and detection rate using 200 serum samples. Results: Our results showed that the LMTIA assay could detect the 10 4 dilution of DNA extracted from the positive reference serum sample, which was the same as that of the commercial real-time PCR kit. The coincidence rate between the two assays was 100%. Conclusions The LMTIA assay had high sensitivity, good detection, and simple operation. Thus, it is suitable for facilitating preliminary and cost-effective surveillance for the prevention and control of ASFV.