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J C Ansel

Publications and source records attributed to J C Ansel.

At least 37 records · Page 2Linked to original sources
PubMed1999

Proteinase-activated receptor-2 in human skin: tissue distribution and activation of keratinocytes by mast cell tryptase.

Proteinase-activated receptor-2 (PAR-2) is a G-protein coupled receptor. Tryptic proteases cleave PAR-2 exposing a tethered ligand (SLIGKV), which binds and activates the receptor. Although PAR-2 is highly expressed by cultured keratinocytes and is an inflammatory mediator, its precise localization in the normal and inflamed human skin is unknown, and the proteases that activate PAR-2 in the skin have not been identified. We localized PAR-2 in human skin by immunohistochemistry, examined PAR-2 expression by RT-PCR and RNA blotting, and investigated PAR-2 activation by mast cell tryptase. PAR-2 was localized to keratinocytes, especially in the granular layer, to endothelial cells, hair follicles, myoepithelial cells of sweat glands, and dermal dendritic-like cells. PAR-2 was also highly expressed in keratinocytes and endothelial cells of inflamed skin. PAR-2 mRNA was detected in normal human skin by RT-PCR, and in cultured human keratinocytes and dermal microvascular endothelial cells by Northern hybridization. Trypsin, tryptase and a peptide corresponding to the tethered ligand (SLIGKVNH2) increased [Ca2+]i in keratinocytes, measured using Fura-2/AM. Although tryptase-containing mast cells were sparsely scattered in the normal dermis, they were numerous in the dermis in atopic dermatitis, and in the dermis, dermal-epidermal border, and occasionally within the lower epidermis in psoriasis. Tryptase may activate PAR-2 on keratinocytes and endothelial cells during inflammation.

Biological Transport↗
PubMed1998

Protein gene product 9.5 is expressed by fibroblasts in human cutaneous wounds.

In a study initially designed to evaluate reinnervation of human cutaneous wounds using an antibody to the neuroneal marker protein gene product (PGP) 9.5, we observed marked immunostaining of cells with morphologic features of fibroblasts in the wounds. PGP 9.5 has recently been shown to be an important enzyme in the highly conserved ubiquitin system of proteolysis. Because the ubiquitin system is known to play an important role in regulating the cell cycle, the presence of PGP 9.5 in cells at a wound site was of considerable interest. Our objectives were to clarify the time frame for the appearance of PGP 9.5 and ubiquitin in wounds, to verify that PGP 9.5 is produced by wound fibroblasts, and to evaluate a potential role for these proteins in the tissue repair process. Standard incisional human wounds were stained with antibodies specific for PGP 9.5 and ubiquitin. At 7 d, stellate cells with morphologic features of fibroblasts stained for PGP 9.5, whereas earlier wounds were generally negative. In 14 and 21 d incised wounds and in chronic granulation tissue from nonhealing ulcers there was strong cellular staining for PGP 9.5 and for ubiquitin. These stellate cells also showed expression of mRNA for PGP 9.5 by reverse transcriptase-polymerase chain reaction in situ hybridization. PGP 9.5 was detected in cultured fibroblasts both by reverse transcriptase-polymerase chain reaction and by northern blot analysis. Confocal microscopy showed colocalization of antibodies to PGP 9.5 and prolyl-4-hydroxylase (a fibroblast marker) as well as colocalization of PGP 9.5 and the platelet derived growth factor beta receptor. We conclude that ubiquitin and PGP 9.5 were expressed by fibroblasts during the granulation tissue and remodeling phases wound healing. The mRNA for PGP 9.5 was demonstrated in stellate cells in chronic wounds and in fibroblasts in culture. The appearance of these degradative proteins in later wounds suggests a downregulation function in the wound healing response.

Apoptosis↗
PubMed1998

Inhibition of murine melanoma growth by granulocyte-macrophage colony stimulating factor gene transfection is not haplotype specific.

Granulocyte-macrophage colony stimulating factor (GM-CSF) has been shown to inhibit the growth and progression of murine melanoma cells in syngeneic C57BL/6 (H-2b) recipient animals. We now demonstrate that this effect is not specific to melanomas derived from a single strain of mice by examining the subcutaneous growth of K1735 murine melanoma cells (H-2k) transfected with GM-CSF in a syngeneic mouse model. Non-GM-CSF-secreting melanoma cells (parental K1735 and K1735 cells transfected with the GM-CSF gene in antisense orientation) generated tumours that reached a mean volume of 4000 mm3 30-40 days, with a mean survival of 40 days after tumour cell injection. In contrast, 90% of the mice injected with three different clones of GM-CSF-producing K1735 melanomas developed no measurable tumours and were healthy and tumour-free when followed for over 300 days post-inoculation. Additionally, mice injected with GM-CSF-secreting K1735 cells developed long-lasting immunity to the parental melanoma cell line challenge in vivo. A dense neutrophilic and lymphocytic inflammatory infiltrate as well as large numbers of dendritic cells were detected only at the inoculation sites of the GM-CSF-producing melanoma cells. Thus, these studies demonstrate for the first time that GM-CSF inhibits melanoma growth in a second genetically distinct MHC tumour-host model system and further support the use of GM-CSF in clinical trials in the treatment of advanced malignant melanoma in humans.

Animals↗
PubMed1998

In vivo human melanoma cytokine production: inverse correlation of GM-CSF production with tumor depth.

Melanomas produce multiple cytokines which may influence their growth in vivo. Experimental evidence suggests that granulocyte macrophage-colony stimulating factor (GM-CSF) can induce a potent anti-melanoma response. whereas interleukin-8 (IL-8) may act as a growth factor in human melanoma. Little is currently known regarding the production of these cytokines by human melanoma in vivo. In this study we tested the hypothesis that endogenous production of GM-CSF and IL-8 can be correlated with the depth of human malignant melanoma surgical specimens. We examined 45 melanocytic human tissue samples consisting of 27 primary cutaneous melanomas, 9 metastatic melanomas, and 9 dysplastic nevi for in vivo GM-CSF and IL-8 production using immunohistochemistry. The majority of thin melanomas (< or = 0.76 mm) stained highly positive for GM-CSF with little or no staining for IL-8 whereas the medium (>0.76- < or = 4.0 mm) and thick (>4.0 mm) melanoma specimens showed little or no staining for GM-CSF and significant amounts of IL-8 staining. Metastatic melanoma as well as dysplastic nevi specimens had little or no GM-CSF and IL-8 staining. These results support the hypothesis that endogenous melanoma cytokines such as GM-CSF and IL-8 with opposing effects on tumor progression play an important role in melanoma growth and regulation.

Biomarkers, Tumor↗
PubMed1998

Neuropeptide regulation of human dermal microvascular endothelial cell ICAM-1 expression and function.

There is increasing evidence that sensory nerves may participate in cutaneous inflammatory responses by the release of neuropeptides such as substance P (SP). We examined the direct effect of SP on human dermal microvascular endothelial cell (HDMEC) intercellular adhesion molecule 1 (ICAM-1) expression and function. Our results indicated that, although cultured HDMEC expressed mRNA for neurokinin receptors 1, 2, and 3 (NK-1R, NK-2R, and NK-3R), SP initiated a rapid increase in HDMEC intracellular Ca2+ levels, primarily by the activation of NK-1R. Immunohistochemistry studies likewise demonstrated that HDMEC predominantly expressed NK-1R. The addition of SP to HDMEC resulted in a rapid increase in cellular ICAM-1 mRNA levels, followed by a fivefold increase in ICAM-1 cell surface expression. This functionally resulted in a threefold increase in 51Cr-labeled binding of J-Y lymphoblastoid cells to HDMEC. In vivo studies demonstrated a marked increase in microvascular ICAM-1 immunostaining 24 and 48 h after application of capsaicin to the skin. These results indicate that neuropeptides such as SP are capable of directly activating HDMEC to express increased levels of functional ICAM-1 and further support the role of the cutaneous neurological system in modulating inflammatory processes in the skin.

Capsaicin↗
PubMed1998

A 15-year follow-up of AJCC stage III malignant melanoma patients treated postsurgically with Newcastle disease virus (NDV) oncolysate and determination of alterations in the CD8 T cell repertoire.

BACKGROUND: The development of effective adjuvant therapies for the treatment of high-risk melanoma patients is critical for the prevention of metastatic disease and improvement of patient survival. Active specific immunotherapy has been tested as an adjuvant treatment in numerous clinical trials with overall limited, but occasionally promising, success rates. Newcastle disease virus (NDV) oncolysate has been utilized as an adjunctive immunotherapeutic agent in the postsurgical management of these patients. A phase II study initiated in 1975 using adjuvant vaccine therapy composed of allogeneic and autologous human melanoma cells infected with live NDV (NDV oncolysate) in patients with AJCC stage III melanoma following therapeutic lymph node dissection has shown >60% survival rate at 10 years with no adverse effects. Continued long-term analysis of trials with promising early results as well as assessment of immunologic responses generated in these patients may result in improved therapeutic decisions for clinical trials in the future. MATERIALS AND METHODS: We analyzed the 15-year survival of patients treated postsurgically with NDV oncolysate in the phase II study described above. In an attempt to understand the immunological effects of this treatment, we have also carried out a comprehensive analysis of the peripheral blood T cell repertoire in these patients. RESULTS: The overall 15-year survival of this group of patients is 55%. Previous studies have suggested that improved outcome in patients undergoing immunotherapy is correlated with increased numbers of CD8(+)CD57(+) cells. In surviving patients, we observed a striking oligoclonality in the CD8(+) T cell population in peripheral blood, which reflects clonal expansions in the CD8(+)CD57(+) subset. CONCLUSIONS: The data suggest that adjuvant vaccination with NDV oncolysates is associated with prolonged survival of patients with lymph node-positive malignant melanoma and that CD8(+) T cells may be an important component of therapeutic efficacy.

Adult↗
PubMed1997

Interactions of the skin and nervous system.

There is increasing experimental evidence that the neurologic system can directly participate in cutaneous inflammation and wound healing. Recent studies indicate that neuropeptides released by cutaneous nerves such as c-fibers can activate a number of target cells including keratinocytes, Langerhans cells, mast cells, and endothelial cells. One such neuropeptide, substance P (SP), is able to specifically bind to murine and human keratinocytes and induce the release of cytokines such as interleukin 1 (IL-1). Other studies demonstrate that SP can also activate mast cells to produce the potent pro-inflammatory cytokine tumor necrosis factor alpha (TNF alpha). More recently, we examined the effect of cutaneous neuropeptides on human dermal microvascular endothelial cell (HDMEC) activities. Our studies indicate that the c-fiber-derived calcitonin gene-related peptide (CGRP) is capable of stimulating HDMEC to secrete the neutrophil chemotactic factor interleukin 8 (IL-8). In addition, SP is able to directly activate HDMEC to express high levels of the important cellular adhesion molecule vascular cellular adhesion molecule 1 (VCAM-1). Thus, these studies support the role that the neurologic system may play in mediating the biologic processes that occur during inflammation and wound healing in the skin.

Animals↗
PubMed1997

Trauma and alkali burns induce distinct patterns of cytokine gene expression in the rat cornea.

Cytokines such as the interleukins (IL) and tumor necrosis factor alpha (TNF alpha) have traditionally been associated with paracrine regulation of immune reactions. These proteins also have properties suggestive of functional roles in the inflammatory and reparative responses to tissue injury. In this study, mRNA levels for IL-1 alpha, IL-1 beta, IL-6, TNF alpha, interferon gamma, transforming growth factor beta 1, and CD4 were monitored in rat corneas at times from 1 hour through 2 weeks after incisional trauma or alkali burns. Transcripts for IL-1 alpha, TNF alpha, and TGF beta 1 were present in most corneal samples; whereas those for IFN gamma and CD4 were not detected. As early as 1 hour following either of these non-immunologic forms of injury, expression of IL-6 mRNA levels was induced. Only in corneas with alkali burns did IL-6 induction persist from days 1 through 7. The alkali-injured corneas also had markedly increased IL-1 beta mRNA levels from days 1 through 7. These observations indicate that cytokine mRNA is induced in the cornea by trauma without an apparent immunologic stimulus. Our data are consistent with the hypothesis that corneal tissues respond to different types of injury with different patterns of cytokine gene expression.

Animals↗
PubMed1997

Ultraviolet irradiation induces the production of multiple cytokines by human corneal cells.

PURPOSE: Ultraviolet (UV) irradiation exposure represents a significant environmental and occupational hazard that can cause acute and chronic inflammatory changes in the exposed cornea. Acute exposure to solar UV irradiation or to UV irradiation from such artificial sources as tanning lamps can result in severe pain and inflammation in the cornea. Chronic exposure to solar UV irradiation is associated with several external eye diseases including pterygium and squamous metaplasia or carcinoma. In the skin, inflammatory responses to UV exposure appear to be mediated by the release of inflammatory cytokines. The role of corneal-derived cytokines in UV-mediated corneal inflammation has not been established. In this study, the effect of UV exposure on the production of proinflammatory cytokines by corneal cells was examined. METHODS: Cultured human corneal stroma cells and whole human corneas received UV irradiation (10 to 100 mJ/cm2), and the production of the proinflammatory cytokines interleukin (IL)-1, IL-6, IL-8, and tumor necrosis factor alpha (TNF alpha) was measured by Northern blot analysis, enzyme-linked immunosorbent assay, cytokine bioassays, and immunohistochemical analysis. RESULTS: The results indicate that acute UV exposure leads to a significant increase in the production of IL-1, IL-6, IL-8, and TNF alpha in human corneal stroma cells. Similarly, acute UV irradiation of whole human corneas ex vivo induces a significant increase in the production of IL-1, IL-6, IL-8, and TNF alpha. CONCLUSIONS: Acute UV irradiation exposure results in the induction of cornea-derived proinflammatory cytokines. The local release of these proinflammatory cytokines by cells in the irradiated cornea may be responsible for UV-mediated corneal inflammation.

Blotting, Northern↗
PubMed1996

Antitumor effects of granulocyte-macrophage colony-stimulating factor production by melanoma cells.

The use of immunomodulating gene therapy in the treatment of malignant disease is under intensive investigation. In this study, we examined the potential of melanoma-derived granulocyte-macrophage colony-stimulating factor (GM-CSF) to inhibit melanoma progression in a murine model. The HGH18 murine melanoma cell line was transfected with the murine GM-CSF gene in a SV40 expression vector that resulted in melanoma clones that produced varying amounts of GM-CSF. Syngeneic mice inoculated s.c. with HFH18 parental melanoma cells or HFH18 cells transfected with the GM-CSF gene n the noncoding 3'-5' orientation [HFH18/GM-CSF(-) cells] develop large tumors that reach a mean tumor volume of 3300 mm3 by day 30. In contrast, animals inoculated with two melanoma clones producing high levels of GM-CSF [HFH18/GM-CSF(++) and HFH18/GM-CSF(+ + +)] either completely reject the tumor cells or develop tumors with a mean volume of only 40 mm3. In comparison, animals inoculated with a melanoma clone producing low levels of GM-CSF [HFH18/GM-CSF(+)] develop large tumors averaging 2000 mm3, thus demonstrating a dose-response effect of tumor inhibition by melanoma-derived GM-CSF. Additionally, vaccination with irradiated GM-CSF-producing melanoma cells conferred optimal immunogenicity against a subsequent challenge with HFH18 cells. Tissue sections from excised GM-CSF-producing tumor cell inoculation sites but not from HFH18 parental or HFH18/GM-CSF(-) inoculation sites demonstrate a dense inflammatory infiltrate composed of neutrophils, tissue macrophages, and numerous CD4- and CD8-positive lymphocytes but few melanoma cells. Large numbers of dendritic cells and cells expressing the B7-2 costimulatory molecule are detected only within HFH18/GM-CSF(+ + +) melanoma inoculation sites. Our results lend further support to clinical trials of GM-CSF gene therapy in the treatment of advanced malignant melanoma, possibly by the recruitment of dendritic antigen-presenting cells.

Animals↗
PubMed1995

Novel production of interleukin-1 receptor antagonist peptides in normal human cornea.

Interleukin-1 receptor antagonist (IL-1ra) is an important modulator of IL-1 activity in a variety of tissues. IL-1ra is differentially produced by different cell types as a 22-26-kD secreted peptide (sIL-1ra) and/or a smaller 16- or 18-kD intracellular peptide (icIL-1ra). This study was undertaken to evaluate the production of IL-1ra in the human cornea. IL-1ra mRNA can be detected in early passage human corneal epithelial cells and corneal stromal fibroblasts and is significantly enhanced by IL-1. Corneal endothelial cells do not express IL-1ra mRNA. Immunohistochemical studies of cultured corneal cells and whole human cornea demonstrate IL-1ra protein production by both the epithelial and stromal cells but not the endothelial cells. Reverse transcriptase polymerase chain reaction, ELISA, and immunoprecipitation studies indicate that corneal epithelial cells are capable of producing both icIL-1ra and sIL-1ra forms of IL-1ra whereas the corneal stromal cells produce only icIL-1ra. In addition to the larger 18-kD icIL-1ra, both corneal epithelial and stromal cells are also capable of producing a smaller recently described 16-kD icIL-1ra. Thus, the differential production of IL-1ra in the human cornea is unique; whereas both epithelial and stromal cells produce icIL-1ra (type 1 and type 2), the epithelial cells appear to also produce sIL-1ra. It is proposed that these IL-1ra proteins may play an important role in regulating IL-1-induced corneal inflammation.

Adult↗
PubMed1995

Mast cells are a major source of basic fibroblast growth factor in chronic inflammation and cutaneous hemangioma.

Mast cells play an essential role during development of inflammation after chemical and immunological insults and have been implicated in tissue fibrosis and angiogenesis. The exact contribution of mast cells to these conditions is largely unknown. In this study, we found that a potent angiogenic and mitogenic polypeptide, basic fibroblast growth factor (bFGF), is localized to the majority of mast cells from normal skin and lung and in tissue samples characterized by fibrosis, hyperplasia, and neovascularization. Using specific antibodies to mast cell tryptase, tissue macrophage, and bFGF, we demonstrate that cytoplasmic bFGF immunoreactivity is localized to 96.8 +/- 9.6% of tryptase-positive cells in human fibrotic lung tissue (n = 10), 82.3 +/- 6.9% of tryptase-positive cells in rheumatoid synovia (n = 6), and 93.1 +/- 4.8% of tryptase-positive cells in skin hemangioma (n = 5). Moreover, these tryptase-positive cells comprise a major portion (86 to 97%) of nonvascular cells exhibiting cytoplasmic bFGF staining in these tissues. In contrast, macrophage-like cells contribute less than 10% of the bFGF-positive cells in the same samples. The specificity of the immunostaining results was supported by the finding that cultured human mast cells (HMC-1) express both bFGF mRNA and protein. Our data indicate that mast cells, a primary source of heparin, also serve as a significant source of a heparin-binding growth factor, bFGF, in these disease processes. These observations suggest that mast cells may contribute to these pathological conditions by releasing this polypeptide.

Arthritis, Rheumatoid↗
PubMed1995

Detection of mRNA for the cytokines, interleukin-1 alpha and interleukin-8, in corneas from patients with pseudophakic bullous keratopathy.

PURPOSE: Cytokines have been implicated in corneal inflammatory diseases. The authors sought to determine if corneal diseases with different patterns of inflammation are accompanied by characteristic patterns of cytokine expression. METHODS: The authors used reverse transcription-polymerase chain reaction to detect mRNA for 12 specific cytokines from patients with Fuch's dystrophy (n = 7), pseudophakic bullous keratopathy (n = 12), or normal corneas (n = 4). RESULTS: Using Wilcoxon rank sum analysis, mRNA for interleukin (IL)-1 alpha or IL-8 was significantly more abundant in corneas from patients with pseudophakic bullous keratopathy relative to either comparison group. mRNA for the T-cell marker, CD4, and for T-cell derived cytokines, IL-2, IL-4, and interferon gamma, could not be detected in any corneal sample. Message for IL-1 receptor antagonist and transforming growth factor-beta 1 or -beta 2 was readily detectable in most corneas regardless of diagnosis. CONCLUSION: The findings indicate that the pattern of cytokine mRNA expression reflects differences in the pathogenesis of these corneal diseases.

Aged↗
PubMed1994

Melanoma-derived interleukin 6 inhibits in vivo melanoma growth.

Malignant melanomas are capable of producing a wide range of cytokines with multiple biologic functions, including interleukin 6 (IL-6). We have observed an inverse relationship between IL-6 production of three B16-derived murine melanoma cell lines (NP133, HFH18, and HFH(M)) and the tumorigenicity of these melanoma cells in syngeneic mice. To further test the effect of IL-6 on melanoma growth, a non-IL-6-producing murine B16-derived melanoma cell line (HFH18) was transfected with a murine IL-6 expression vector, resulting in stable transfectants (HFH18/IL-6(+)) that expressed significant amounts of IL-6 mRNA and secreted high levels of bioactive IL-6. Syngeneic C57BL/6 mice inoculated subcutaneously with HFH18/IL-6(+) cells developed tumors that reached a final mean diameter of less than half the size of tumors that developed in mice inoculated with either HFH18 parental or HFH18 cells transfected with the IL-6 cDNA in the non-coding 3'-5' orientation (HFH18/IL-6(-) cells). In addition, mice bearing IL-6-producing HFH18/IL-6(+) tumors survived twice as long as mice bearing HFH18 parental or HFH18/IL-6(-) tumors. The specificity of melanoma growth inhibition by IL-6 was confirmed by the reversal of the slow-growing phenotype of HFH18/IL-6(+) cells by local peritumoral administration of neutralizing alpha-murine IL-6 antibody. IL-6-producing melanoma cells exerted a growth-inhibitory effect on distant parental tumors in a dose-dependent manner. The growth of HFH18/IL-6(+) melanomas was also decreased in nude mice, suggesting that melanoma-derived IL-6 may mediate this anti-tumor effect independently of a normal host B- and T-cell immune response. Thus, melanoma-derived IL-6 exerts a significant inhibitory effect on cutaneous melanoma growth and progression. These results indicate that melanoma cytokines may have a profound effect on tumor pathogenesis.

Animals↗
PubMed1994

Proopiomelanocortin-derived peptides are synthesized and released by human keratinocytes.

Proopiomelanocortin (POMC), the precursor for melanotropic, corticotropic, and opioid peptides such as alpha-melanocyte-stimulating hormone (alpha MSH), ACTH, and other related peptides, was originally identified as a product of the pituitary gland. However, recent evidence shows that POMC products can also be produced by nonpituitary tissues. Because keratinocytes, the major constituent of the epidermis exhibit the capacity to release a variety of proinflammatory and immunomodulatory mediators, the present study was performed to investigate whether human keratinocytes are able to produce POMC-derived peptides. Supernatants of human normal keratinocytes and an epidermal carcinoma cell line (A431) contained significant levels of immunoreactive alpha MSH and ACTH. Upon immuneprecipitation and size-exclusion chromatography, keratinocyte-derived alpha MSH exhibited a molecular mass of approximately 1 kD and was biologically active as demonstrated in a tyrosinase bioassay. Northern blot analysis revealed the expression of POMC-specific transcripts (1.3 kb) in both normal keratinocytes and A431 cells. The production of alpha MSH and ACTH could be significantly upregulated both at the protein and mRNA level upon treatment with phorbol myristate acetate, ultraviolet light, or interleukin 1. These data provide first evidence that human keratinocytes produce POMC-derived peptides such as alpha MSH and ACTH. Because POMC-derived peptides recently have been recognized as potent immunomodulatory mediators, their presence in the epidermis may have a major impact on the skin immune system.

Adrenocorticotropic Hormone↗