Induction of interferon gamma in human gingival fibroblasts challenged with phytohaemagglutinin

Solanum lycopersicum (Tomato)-Derived Nanovesicles Accelerate Wound Healing by Eliciting the Migration of Keratinocytes and Fibroblasts

Plant-derived nanovesicles have been considered interesting in medicine for their breakthrough biological effects, including those relevant to wound healing. However, tomato-derived nanovesicles (TDNVs) have not been studied for their effects on wound closure yet. TDNVs were isolated from Solanum lycopersicum (var. Piccadilly) ripe tomatoes by ultracentrifugation. Extract (collected during the isolation procedure) and NVs (pellet) were characterized by transmission electron microscopy and laser Doppler electrophoresis. Wound healing in the presence of Extract or NVs was analyzed by a scratch assay with monocultures of human keratinocytes (HUKE) or NIH-3T3 mouse fibroblasts. Cell proliferation and migration were studied by MTT and agarose spot assay, respectively. The vesicles in the Extract and NV samples were nanosized with a similar mean diameter of 115 nm and 130 nm, respectively. Both Extract and NVs had already accelerated wound closure of injured HUKE and NIH-3T3 monocultures by 6 h post-injury. Although neither sample exerted a cytotoxic effect on HUKE and NIH-3T3 fibroblasts, they did not augment cell proliferation. NVs and the Extract increased cell migration of both cell types. NVs from tomatoes may accelerate wound healing by increasing keratinocyte and fibroblast migration. These results indicate the potential therapeutic usefulness of TDNVs in the treatment of chronic or hard-to-heal ulcers.

A review of T helper 17 cell-related cytokines in serum and saliva in periodontitis

Periodontitis is a chronic inflammatory disease with a complex underlying immunopathology. Cytokines, as molecular mediators of inflammation, play a role in all stages of disease progression. T helper 17 (Th17) cells are thought to play a role in periodontitis. Th17 cell development and maintenance requires a pro-inflammatory cytokine milieu, with many of the cytokines implicated in the pathogenesis of periodontitis. Serum and saliva are easily accessible biofluids which can represent the systemic and local environment to promote the development of Th17 cells. Here we review human clinical studies that investigate IL-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, sCD40L and TNF-α in serum and saliva in periodontitis. We highlight their putative role in the pathogenesis of periodontitis and place them within a wider context of animal and other clinical studies.

Cytokine Interferon-γ suppresses the function of capsule myofibroblasts and induces cell apoptosis

Myofibroblasts (MFs), a contractile subset of fibroblasts, play a pivotal role in physiological wound healing and in the development of many fibroconnective disorders. The complex cytokine network regulating the function of MFs in joint stiffness is still poorly understood. In this in vitro study, we investigated the effect of the cytokine Interferon-gamma (IFN-γ) on MFs isolated from human joint capsules. MFs were cultivated either in the presence of increasing concentrations of IFN-γ alone or in combination with IFN-γ neutralizing antibodies. Cell viability, cytotoxicity, apoptosis, and mRNA gene expression of the MF markers alpha-smooth muscle actin (α-SMA) and collagen type I were analyzed in MF cultures. Contraction potential was analyzed in an established collagen gel contraction assay simulating the extracellular matrix. Using immunofluorescence staining, we could verify that MFs express IFN-γ-receptor (R)-1 on their membrane. IFN-γ decreased MF viability and significantly elevated the apoptosis rate in a dose-dependent manner. IFN-γ down-regulated α-SMA and collagen type I mRNA expression which was associated with a diminished MF mediated contraction of the gel matrices. These effects were suppressed by simultaneous treatment of cells with a neutralizing IFN-γ antibody. Our experiments confirm the hypothesis that the cytokine IFN-γ is a crucial component of the regulatory network of capsule MFs. IFN-γ notably influences the ability of MFs to contract collagen matrices by suppressing α-SMA gene expression. IFN-γ is toxic for MFs in high concentrations and may negatively regulate the number of pro-fibrotic MFs during the healing process via induction of cell apoptosis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2524-2533, 2017.

Epidermal Dysfunction Leads to an Age-Associated Increase in Levels of Serum Inflammatory Cytokines

Even though elderly populations lack visible or other clinical signs of inflammation, their serum cytokine and C-reactive protein levels typically are elevated. However, the origin of age-associated systemic inflammation is unknown. Our previous studies showed that abnormalities in epidermal function provoke cutaneous inflammation, and because intrinsically aged skin displays compromised permeability barrier homeostasis and reduced stratum corneum hydration, we hypothesized here that epidermal dysfunction could contribute to the elevations in serum cytokines in the elderly. Our results show first that acute disruption of the epidermal permeability barrier in young mice leads not only to a rapid increase in cutaneous cytokine mRNA expression but also an increase in serum cytokine levels. Second, cytokine levels in both the skin and serum increase in otherwise normal, aged mice (>12 months). Third, expression of tumor necrosis factor-α and amyloid A mRNA levels increased in the epidermis, but not in the liver, in parallel with a significant elevation in serum levels of cytokines. Fourth, disruption of the permeability barrier induced similar elevations in epidermal and serum cytokine levels in normal and athymic mice, suggesting that T cells play a negligible role in the elevations in cutaneous and serum inflammatory cytokines induced by epidermal dysfunction. Fifth, correction of epidermal function significantly reduced cytokine levels not only in the skin but also in the serum of aged mice. Together, these results indicate that the sustained abnormalities in epidermal function in chronologically aged skin contribute to the elevated serum levels of inflammatory cytokines, potentially predisposing the elderly to the subsequent development or exacerbation of chronic inflammatory disorders.

Cellular sources and inducers of cytokines present in acute wound fluid

Acute wounds contain many biological active molecules, including several cytokines and growth factors. However, the cellular sources of each molecule, as well as the stimuli inducing them, are poorly characterized. We quantified the levels of 27 cytokines, chemokines, and growth factors in acute wound fluid in a luminex-based assay. The acute wound fluid contained particularly high levels of IL-6 and IL-8, as well as elevated levels of MCP-1, IL-1RA, PDGF, IP-10, IFN-γ, and TNF-α. Surprisingly, the amounts of IL-1β and IL-10 were relatively low. To characterize the cellular sources of these molecules, we analyzed supernatants from monocytes, neutrophils, keratinocytes, fibroblasts, and endothelial cells stimulated with pro- and anti inflammatory cytokines, and different Toll-like receptor (TLR) ligands. The different cell types showed overlapping but distinct patterns of production of signal molecules, as well as sensitivity to ligands. Among pro-inflammatory cytokines, IL-1β was the most potent inducer of signal molecule production. Furthermore, keratinocytes and endothelial cells were in particular responsive to the Toll-like receptor-3 ligand poly I:C. New interactions between cytokines and growth factors were revealed, which may have important roles in wound healing, including IL-1β-induced IFN-γ and IL-10-induced VEGF.

Cross-Talk between T Cells and Innate Immune Cells Is Crucial for IFN-γ-Dependent Tumor Rejection

Though the importance of IFN-gamma in tumor immunity has been well-demonstrated, little is known about its source and how it is induced. By using various bone marrow chimeric mice, we show here that IFN-gamma essential for tumor immunity is solely produced by hemopoietic cells. Surprisingly, IFN-gamma derived from T cells was not necessary for tumor immunity in this model. In the immunized mice, in which only innate immune cells have the IFN-gamma-producing potential, tumors were efficiently rejected. The innate immune cells, such as NK1.1(+) cells and CD11b(+) cells, can provide sufficient amounts of IFN-gamma which requires, however, the help of T cells. The close cooperation between T cells and innate immune cells during tumor regression is likely mediated by IL-2. Together, our results clearly illustrate how T cells cooperate with innate immune cells for IFN-gamma-mediated tumor rejection and this may have important indications for clinical trials of tumor immunotherapy.

Characterization of human lung tumor-associated fibroblasts and their ability to modulate the activation of tumor-associated T cells

The tumor microenvironment of human non-small cell lung cancer (NSCLC) is composed largely of stromal cells, including fibroblasts, yet these cells have been the focus of few studies. In this study, we established stromal cell cultures from primary NSCLC through isolation of adherent cells. Characterization of these cells by flow cytometry demonstrated a population which expressed a human fibroblast-specific 112-kDa surface molecule, Thy1, alpha-smooth muscle actin, and fibroblast activation protein, but failed to express CD45 and CD11b, a phenotype consistent with that of an activated myofibroblast. A subset of the tumor-associated fibroblasts (TAF) was found to express B7H1 (PD-L1) and B7DC (PD-L2) constitutively, and this expression was up-regulated by IFN-gamma. Production of cytokines and chemokines, including IFN-gamma, monokine induced by IFN-gamma, IFN-gamma-inducible protein-10, RANTES, and TGF-beta1 was also demonstrated in these cells. Together, these characteristics provide multiple opportunities for the TAF to influence cellular interactions within the tumor microenvironment. To evaluate the ability of TAF to modulate tumor-associated T cell (TAT) activation, we conducted coculture experiments between autologous TAF and TAT. In five of eight tumors, TAF elicited a contact-dependent enhancement of TAT activation, even in the presence of a TGF-beta1-mediated suppressive effect. In the three other tumors, TAF had a net suppressive effect upon TAT activation, and, in one of these cases, blockade of B7H1 or B7DC was able to completely abrogate the TAF-mediated suppression. We conclude that TAF in human NSCLC are functionally and phenotypically heterogeneous and provide multiple complex regulatory signals that have the potential to enhance or suppress TAT function in the tumor microenvironment.

Gene expression profiles of periodontal ligament cells treated with enamel matrix proteins in vitro: analysis using cDNA arrays

BACKGROUND

A number of procedures have been used to achieve periodontal regeneration. Recently, enamel matrix derivative (EMD) has been the subject of significant basic and clinical investigations. The precise molecular events involved in EMD modulation of periodontal wound healing are not completely understood; however, cDNA microarray technology may enable rapid and accurate examination of EMD-mediated changes in gene expression in periodontal ligament (PDL) cells in vitro. The present study was undertaken to explore the selective effects of EMD on the activities of 268 cytokine, growth factor, and receptor genes in PDL.

METHODS

PDL cells were cultured in the absence and presence of EMD at a concentration of 100 microg/ml for 4 days. RNA was extracted and used to generate labeled cDNA probes. These were hybridized to cDNA arrays comprising 268 genes and exposed to x-ray films. Autoradiographs were digitized and analyzed.

RESULTS

Forty-six percent (125 of 268) of the tested genes were found to be expressed by the PDL cells. Of these 125 genes, 38 were differentially expressed by PDL cells which had been cultured in the presence of EMD. Among the 38, 12 were found to be downregulated, notably mostly inflammatory genes, whereas 26 genes demonstrated upregulation, many of these coding for growth factors and growth factor receptors.

CONCLUSIONS

The present study has shown that EMD down-regulates the expression of genes involved in the early inflammatory phases of wound healing while simultaneously upregulating genes encoding growth and repair-promoting molecules. This may partly explain the apparent efficacy of EMD application in periodontal regeneration.

Production of Rantes/CCL5 in human gingival fibroblasts challenged with tumor necrosis factor alpha

Chemokines are small-secreted proteins that stimulate the directional migration of leukocytes and thereby mediate the inflammatory process. The present study investigates the capacity of human gingival fibroblasts to produce the beta chemokine Rantes/CCL5. In situ hybridization, immunohistochemistry and ELISA were used to measure the induction of Rantes/CCL5 at the mRNA and protein levels, both in unstimulated gingival fibroblasts as well as in fibroblasts treated with the proinflammatory cytokines tumor necrosis factor (TNF)alpha or interleukin (IL)-1beta. TNFalpha in different concentrations (0.1-10 ng/ml) induced Rantes/CCL5 mRNA expression and protein production in 24-h cultures of human gingival fibroblasts. The expression of Rantes/CCL5-mRNA and protein production, induced by TNFalpha, was evident at 6 h and thereafter increased continuously during the study period (24 h). IL-1beta (3-300 pg/ml) also enhanced the production of Rantes/CCL5 in gingival fibroblasts. The amount of Rantes/CCL5 induced by IL-1beta (300 pg/ml), however, was less than that induced by TNFalpha (10 ng/ml). The study suggests that human gingival fibroblasts, by producing the chemokine Rantes/CCL5, participate in the regulation of the host response during the inflammatory process in the periodontal tissue.