Objective:To establish an immortalized human keloid fibroblasts(KFbs) cell line and identify its characteristics and functions.Methods:The specimen was obtained from a 32-year-old female patient who underwent surgical resection of an earlobe keloid at Peking University Third Hospital in November 2019. The keloid tissue obtained was removed from the subcutaneous fat and epidermis. It was then separated and cultured using the tissue sticking method to obtain primary KFbs, which were passaged using the trypsin digestion method. After the primary KFbs were infected with an SV40 lentivirus, purified by puromycin, and passaged, a human KFbs cell line was established. Chromosomal karyotype analysis, short tandem repeat (STR) profiling, and gender gene detection were conducted to identify the primary KFbs and the cell line. The CCK-8 method was used to assess the proliferation ability of the cells. Quantitative real-time PCR (qRT-PCR) and Western blotting were used to detect the mRNA and protein expression levels of specific genes (PGK1, ENO1, LDHA, GLUT1, TGF-β1, COL1, COL3, FN). The comparative analysis of relevant data between primary KFbs and the cell line was conducted using t-test, and P<0.05 indicated statistical significance. Results:The morphology of both the primary KFbs and the cell line was typically spindle-shaped. The cell line morphology was basically similar to that of the primary KFbs, which were continuously cultured and passaged for 20 generations. The gender gene(Amelogenin) detection showed both were females. The chromosome karyotyping of the primary KFbs and cell line was satisfactory, maintaining the fundamental characteristics of normal cells without undergoing malignant transformation. The STR identification results showed that no multiple alleles were found in the cell line, indicating a normal cell genotype. Furthermore, the cell line did not match any entries in known cell databases. After 24, 48, and 72 hours of culture, the proliferation ability of the cell line increased by 76.1%, 125.8%, and 60.3% compared to primary KFbs. The proliferation rates of the cell line were significantly faster than those of primary KFbs ( P<0.05). The mRNA and protein expression levels of the aforementioned genes in the cell line showed no significant changes compared to the primary KFbs ( P>0.05). Conclusion:An immortalized human KFbs cell line was successfully established, showing no significant changes in morphology, characterization, and function, while exhibiting a faster proliferation rate compared to that of primary KFbs.

Objective:To establish an immortalized human keloid fibroblasts(KFbs) cell line and identify its characteristics and functions.Methods:The specimen was obtained from a 32-year-old female patient who underwent surgical resection of an earlobe keloid at Peking University Third Hospital in November 2019. The keloid tissue obtained was removed from the subcutaneous fat and epidermis. It was then separated and cultured using the tissue sticking method to obtain primary KFbs, which were passaged using the trypsin digestion method. After the primary KFbs were infected with an SV40 lentivirus, purified by puromycin, and passaged, a human KFbs cell line was established. Chromosomal karyotype analysis, short tandem repeat (STR) profiling, and gender gene detection were conducted to identify the primary KFbs and the cell line. The CCK-8 method was used to assess the proliferation ability of the cells. Quantitative real-time PCR (qRT-PCR) and Western blotting were used to detect the mRNA and protein expression levels of specific genes (PGK1, ENO1, LDHA, GLUT1, TGF-β1, COL1, COL3, FN). The comparative analysis of relevant data between primary KFbs and the cell line was conducted using t-test, and P<0.05 indicated statistical significance. Results:The morphology of both the primary KFbs and the cell line was typically spindle-shaped. The cell line morphology was basically similar to that of the primary KFbs, which were continuously cultured and passaged for 20 generations. The gender gene(Amelogenin) detection showed both were females. The chromosome karyotyping of the primary KFbs and cell line was satisfactory, maintaining the fundamental characteristics of normal cells without undergoing malignant transformation. The STR identification results showed that no multiple alleles were found in the cell line, indicating a normal cell genotype. Furthermore, the cell line did not match any entries in known cell databases. After 24, 48, and 72 hours of culture, the proliferation ability of the cell line increased by 76.1%, 125.8%, and 60.3% compared to primary KFbs. The proliferation rates of the cell line were significantly faster than those of primary KFbs ( P<0.05). The mRNA and protein expression levels of the aforementioned genes in the cell line showed no significant changes compared to the primary KFbs ( P>0.05). Conclusion:An immortalized human KFbs cell line was successfully established, showing no significant changes in morphology, characterization, and function, while exhibiting a faster proliferation rate compared to that of primary KFbs.

Objective:To explore the interleukin-31 protein expression in the hypertrophic scar of incision tissue after surgery and its underlying pathological impact.Methods:From February 2022 to February 2023, three HS patients scar tissue (HS) and their normal skin tissue (Control, NS) were obtained. Two patients were female and one patient was male. The tissues were fixed in 4% formalin and embedded in paraffin. Haematoxylin-eosin (HE) stain and immunohistochemical stain were used to evaluate the epidermal thickness, myofibroblasts of dermis and the expression level of IL-31 between HS and NS.Results:The epidermis thickness was (303.88±46.03) μm in HS group, while (133.02±17.40) μm in NS group ( t=12.60, P<0.001). The expression level of IL-31 protein was measured by IRS score and positive cell density. The IRS score was 9.89±2.03 of the basal layer in HS group and was 4.33±1.66 of the basal layer in NS group. The positive cell density was 786 343.83±159 627.97 of the basal layer in HS group ( P<0.001) and was 555 457.61±128 097.21 of the basal layer in NS group ( P=0.014). In the dermis layer, the IRS score was 7.11±1.05 in HS group and was 4.33±0.71 in NS group, the positive cell density was 156 760.97±26 046.10 in HS group ( P<0.001) and was 49 576.01±52 369.33 in NS group ( P<0.001). In the dermis layer, the count of myofibroblasts was 120.44±15.75 in HS group while was 27.39±14.89 in NS group ( t=23.79, P<0.001). Conclusions:Our study demonstrates that both myofibroblast count and IL-31 protein expression level are notably increased in HS patients. The expression of IL-31 protein is prominent in the cytoplasm of myofibroblasts, basal cells, macrophages and mast cells which could implicate that IL-31 may be a potential therapeutic target to enhance the resolution of HS.

Regeneration and repair are two different forms of human skin wound healing. Adult wounds can form scars through fibrous repair, while fetal skin wounds heal well without scars, and can even regenerate, completely restoring the structure and function of the original tissue. Understanding the different mechanisms of fetal wound healing is essential for developing new scar prevention therapies. In this review, the author summarized the recent research progress in scarless healing of fetal wounds, especially new discoveries in skin cells such as fibroblasts, mesenchymal stem cells and their exosomes and gene expression, immune cells and inflammation. It will be beneficial to develop new method to promote the development of adult wounds to scarless healing, and to provide new ideas for scar treatment and skin regeneration and repair by learning from the mechanism of fetal wound healing.

Regeneration and repair are two different forms of human skin wound healing. Adult wounds can form scars through fibrous repair, while fetal skin wounds heal well without scars, and can even regenerate, completely restoring the structure and function of the original tissue. Understanding the different mechanisms of fetal wound healing is essential for developing new scar prevention therapies. In this review, the author summarized the recent research progress in scarless healing of fetal wounds, especially new discoveries in skin cells such as fibroblasts, mesenchymal stem cells and their exosomes and gene expression, immune cells and inflammation. It will be beneficial to develop new method to promote the development of adult wounds to scarless healing, and to provide new ideas for scar treatment and skin regeneration and repair by learning from the mechanism of fetal wound healing.

Regeneration and repair are two different forms of human skin wound healing. Adult wounds can form scars through fibrous repair, while fetal skin wounds heal well without scars, and can even regenerate, completely restoring the structure and function of the original tissue. Understanding the different mechanisms of fetal wound healing is essential for developing new scar prevention therapies. In this review, the author summarized the recent research progress in scarless healing of fetal wounds, especially new discoveries in skin cells such as fibroblasts, mesenchymal stem cells and their exosomes and gene expression, immune cells and inflammation. It will be beneficial to develop new method to promote the development of adult wounds to scarless healing, and to provide new ideas for scar treatment and skin regeneration and repair by learning from the mechanism of fetal wound healing.

Regeneration and repair are two different forms of human skin wound healing. Adult wounds can form scars through fibrous repair, while fetal skin wounds heal well without scars, and can even regenerate, completely restoring the structure and function of the original tissue. Understanding the different mechanisms of fetal wound healing is essential for developing new scar prevention therapies. In this review, the author summarized the recent research progress in scarless healing of fetal wounds, especially new discoveries in skin cells such as fibroblasts, mesenchymal stem cells and their exosomes and gene expression, immune cells and inflammation. It will be beneficial to develop new method to promote the development of adult wounds to scarless healing, and to provide new ideas for scar treatment and skin regeneration and repair by learning from the mechanism of fetal wound healing.

Keloid is a hyperplastic pathological scar of body caused by infection, trauma, and surgery or formed spontaneously for unknown reasons. It is an excessive tissue response of body to dermal injury. The paper introduces the research advances on inflammatory responses involved in keloid development and keloid treatment by inhibiting inflammatory responses from the aspects of inflammation inducing factors, inflammatory cells, inflammatory mediators, inflammatory effectors, and influencing factors of inflammatory responses. The research results suggest that inflammatory responses are not only essential process to normal wound healing, but also key factors on keloid formation and development.

Pathological scars mostly result from abnormal remodeling after skin trauma, and they are characterized by dysregulated fibroblast proliferation and extracellular matrix deposition. In recent years, several studies have confirmed that autologous fat injections contain a variety of substances that may be involved in the treatment of scars, such as stromal vascular fraction, adipose-derived mesenchymal stem cells and so on. These substances can inhibit the excessive proliferation of fibroblasts and deposition of collagen through related pathways, so as to slow the progression and improve the prognosis of pathological scars. Clinical studies have demonstrated that fat injections can effectively ameliorate the thickness, color, softness and local symptoms of pathological scars. Further understanding of the anti-fibrosis mechanism of adipose tissues will facilitate the development of therapies for pathological scars.

Severe dermal defects caused by burns, trauma, scars, tumor resection and so on are liable to form scar deformities. Dermal substitutes can reduce the formation of abnormal scars during wound healing, and effectively decrease the incidence of pathological scars after scar resection and repair. This review introduces some commonly used dermal substitutes and their clinical application in wound healing and skin repair after scar resection.