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G F Murphy

Publications and source records attributed to G F Murphy.

At least 73 records · Page 4Linked to original sources
PubMed1995

Connective tissue mast cells exhibit time-dependent degranulation heterogeneity.

Previous studies have identified two ultrastructurally distinct forms of mast cell (MC) degranulation following activation. Immunoglobulin E (IgE)-mediated reactions are characterized by a very rapid swelling and fusion of MC granules and abrupt mediator release. In certain chronic disease states (e.g., bullous pemphigoid), there is "piecemeal" degranulation with a more-gradual mediator release effected by microvesicular transport of "pieces" of granules to the cell surface. It is unclear whether these two degranulation patterns are determined by the different natures of the stimuli, heterogeneity among responding MC granules, or temporal factors. To investigate these issues, we have carried out electron microscopic studies with skin biopsies obtained from ragweed-sensitive subjects 15 and 30 s and 1, 3, 5, and 10 min after intradermal ragweed injection. "Anaphylactic"-type granule changes began by 15 s after ragweed injection and were complete by 5 min; unaffected granules were juxtaposed with granules that were swollen and fused. The remaining granules subsequently underwent changes in appearance similar to those seen in piecemeal degranulation. However, microvesicular transport of granule components to the surface was not observed. These findings indicate that skin MC changes in sites of IgE-mediated reactions include not only the typical very rapid anaphylactic degranulation but also a slower onset of gradual alteration of other granules, frequently within the same MC. These different patterns could reflect MC granule heterogeneity with attendant different responses to IgE-mediated stimuli.

Anaphylaxis↗
PubMed1995

Serine proteinases are regionally segregated within mast cell granules.

BACKGROUND: By ultrastructure, human skin mast cell granules exhibit amorphous regions situated next to crystalline regions with scroll, lamellar, and grating/lattice-like configurations. The composition and function of these structural domains is unknown. These granules also contain large amounts of three serine proteinases termed tryptase, chymase, and cathepsin G. In this study, subgranular proteinase distribution is correlated with granule ultrastructure. EXPERIMENTAL DESIGN: Human skin sections were immunolabeled for each proteinase, visualized with gold-conjugated antibodies, and then stained with heavy metals to enhance granule features. Both single and double labeling experiments were analyzed. RESULTS: Comparison of the immunogold labeling patterns revealed nonrandom distributions for each proteinase within most granules. At low magnification, chymase and cathepsin G immunoreactivity was found preferentially over more electron-dense granule subregions, whereas tryptase immunoreactivity was found preferentially over less electron-dense subregions. The complimentary staining pattern of the proteinases was also observed in double labeling experiments where tryptase immunoreactivity was compared directly with that of chymase or cathepsin G. Higher magnification of sections revealed that electron-dense granule areas corresponded to amorphous regions, whereas less dense regions most often demonstrated crystalline structures. CONCLUSIONS: These observations correlate the subgranular distribution of serine proteinases with specific granule ultrastructure and suggest that the different morphologic features within granules may be related, in part, to the packaging of serine proteinases. Human mast cells differ from human basophils and rat mast cells by virtue of the presence of high amounts of tryptase and the presence of crystalline substructures. This raises the possibility that association of tryptase with crystalline structures reflects a specialized form of packaging permitting efficient storage of high levels of this proteinase within mast cell granules.

Cathepsin G↗
PubMed1994

Familial paraganglioma.

Extra-adrenal pheochromocytomas and paragangliomas are rare tumors of neural crest origin, most commonly found in the retroperitoneum. Because these tumors are so uncommon, relatively little is known about their natural history. Comparisons between adrenal pheochromocytomas and extra-adrenal pheochromocytomas have appeared in the medical literature. Like pheochromocytomas, paragangliomas may occur as functional or nonfunctional tumors. Furthermore, although the hereditary occurrence of pheochromocytomas is well documented, the familial nature of paragangliomas is unclear. We present the first report of a mother and son with nonfunctional paragangliomas occurring in the same anatomic location and describe their care and treatment.

Adolescent↗
PubMed1994

Chronic nephrotoxicity in psoriatic patients treated with low-dose cyclosporine.

Chronic nephrotoxicity is a major complication in high-dose cyclosporine treatment. We examined the glomerular filtration rate, renal plasma flow, and kidney biopsies of 15 psoriatic patients treated with low-dose cyclosporine (< or = 5 mg/kg/d) for 30 months (25 to 35 months) 1 month after drug withdrawal. The mean (95% confidence interval) age of the patients in the study was 44 years (38 to 50 years). Their serum creatinine levels pretreatment and at the time of the study were 0.94 mg/dL (0.85 to 1.0 mg/dL) and 1.2 mg/dL (1.1 to 1.3 mg/dL). Seven patients had a decreased glomerular filtration rate and four of them also had a reduced renal plasma flow, below the 2.5 percentile of normal. Four patients had moderate tubulointerstitial scarring and arteriolopathy, while the remaining patients had mild structural abnormalities. The severity of acute nephrotoxicity during treatment and chronic structural injury were highly correlated (r = 0.81; P < 0.0003). Recurrent episodes of severe acute nephrotoxicity (defined as reversible increase of serum creatinine > 90% of baseline value) was a marker for moderate chronic nephrotoxicity. No correlation was found between chronic structural injury and patient age, sex, pretreatment creatinine level, blood pressure (pretreatment or during treatment), cyclosporine dose and treatment duration, and cyclosporine blood levels. In seven patients continued on cyclosporine for another 12 months (10 to 14 months), repeat studies showed no interval changes. Despite 40 months (30 to 51 months) of treatment, all but one of these seven patients (with previous hypertension and atherosclerotic vascular disease) had mild functional and structural abnormalities. None had any severe acute nephrotoxicity at any time.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Role of mast cells in early epithelial target cell injury in experimental acute graft-versus-host disease.

The skin is a major target organ for graft-versus-host disease (GVHD), the principal complication of allogeneic bone marrow transplantation. The purpose of the present study was to test whether mast cell degranulation might be related to early target cell injury in the development of acute GVHD. We employed two irradiated murine strain combinations, one in which disease was mediated by CD4+ effector T cells (B10.D2-->DBA/2), and the other by CD8+ effector T cells (B10.BR-->CBA). As compared to controls, both models exhibited mast cell degranulation of differing extents and patterns, as well as dyskeratosis in the epidermis before the influx of effector lymphocytes. These results suggested that factors produced and released by degranulated dermal mast cells might contribute to early target cell injury. Accordingly, the possible role of tumor necrosis factor (TNF)-alpha, a cytokine recently discovered in mast cell granules, was investigated by the injection of anti-TNF-alpha antibody during the course of disease mediated by either CD4+ or CD8+ T cells. Although overall survival of recipients undergoing CD4+ T-cell-mediated GVHD was only slightly improved and the extent of mast cell degranulation was not affected by anti-TNF-alpha antibody treatment, the skin exhibited a significant diminution in the number of dyskeratotic cells/linear mm at 3-4 weeks post-transplantation. In contrast, anti-TNF-alpha antibody failed to enhance survival or reduce the number of dyskeratotic cells in the skin during CD8+ T-cell-mediated disease. Finally, to determine whether CD8+ T-cell-mediated GVHD was at all dependent upon mast cell involvement, the C3H.SW-->B6WWv strain combination was utilized, in which recipients were genetically deficient in mast cells. Onset of GVHD was significantly delayed in B6WWv mice and was clearly correlated to the appearance and increase of de novo mast cells at later time points.

Animals↗
PubMed1993

Cutaneous lymphosarcoma and leukemia in a cat.

A cat with cutaneous lymphosarcoma and leukemia, similar to Sézary syndrome in human beings, had initial clinical signs that included pruritus and exfoliative dermatosis, associated with weight loss and lymphadenopathy. Dermatopathologic findings and ultrastructural morphologic features of the circulating cells and cellular infiltrate were consistent with Sézary cells. Cutaneous lymphosarcoma and leukemia should be considered in cats with chronic pruritic exfoliative dermatoses.

Animals↗
PubMed1993

Regulation of Langerhans cell function by nerves containing calcitonin gene-related peptide.

Several observations suggest interactions between the immune and nervous systems. Psoriasis and atopic dermatitis may worsen with anxiety and have been associated with anomalous neuropeptide regulation. Neurotransmitters affect lymphocyte function and lymphoid organs are innervated. Calcitonin gene-related peptide (CGRP) is a neuropeptide and vasodilator that modulates some macrophage functions, including antigen presentation in vitro. CGRP is associated with Langerhans cells (LC) in oesophageal mucosa, particularly during inflammation, is present in epidermal nerves and is associated with Merkel cells. We examined the ability of CGRP to modulate LC antigen-presenting function and asked if CGRP-containing nerves impinge on LC. We report here that CGRP-containing nerve fibres are intimately associated with LC in human epidermis and CGRP is found at the surface of some LC. In three functional assays CGRP inhibited LC antigen presentation. These findings indicate that CGRP may have immunomodulatory effects in vivo and suggest a locus of interaction between the nervous system and immunological function.

Adult↗
PubMed1993

Delayed type hypersensitivity to human cytomegalovirus.

A skin test for immunity to human cytomegalovirus (HCMV) is described in which skin induration is measured after intradermal injection of antigen derived from heat-inactivated Towne strain HCMV or of envelope prepared from the virus. Randomly selected healthy young adult males and females were prescreened for evidence of past infection with HCMV using serologic tests. Each individual was inoculated with heat inactivated whole virion HCMV antigen prepared from serum-free supernatants of HCMV-infected MRC-5 cells, non-infected MRC-5 cell lysates, and Candida extract. HCMV seropositive individuals developed positive skin reactions to both the Candida extract and the HCMV test antigen. No response was observed at the MRC-5 cell lysate inoculation site. The envelope antigen also elicited a response in seropositive individuals. Seronegative individuals who were negative to the HCMV intradermal antigen at the start of the study developed a positive response 1 week after subcutaneous immunization with live attenuated Towne strain HCMV. This response also correlated with the onset of in vitro proliferation responses to HCMV antigens by peripheral blood lymphocytes obtained from the immunized individuals. Furthermore, skin test and lymphocyte proliferation responses remained positive when tested up to 93 days post-immunization. In guinea pig experiments with HCMV, those animals immunized with purified HCMV or a virus envelope preparation developed strong skin reactions to intradermal injection of each of those antigens. In contrast, no reaction was observed in immune animals, either to viral capsid antigen or uninfected cell-lysate antigen, and no reactions were observed to any HCMV antigen in non-immune animals.

Animals↗
PubMed1993

The use of mineral oil to manage the nondeflating Foley catheter.

The Foley catheter provides for urinary drainage by a self-retaining inflatable balloon mechanism. The morbidity associated with its use is minimal. However, blockage of the balloon port occasionally occurs, making its removal difficult. We discuss the various strategies used for catheter removal and recommend the use of mineral oil as the first line of intervention because of its reliability, safety and cost-effectiveness.

Catheterization↗
PubMed1993

Adenovirus-associated hemorrhagic cystitis treated with intravenous ribavirin.

Adenovirus hemorrhagic cystitis following bone marrow transplantation occurs in 2 to 16% of the patients. While usually self-limiting, this disease can cause significant morbidity and even mortality in the immunocompromised patient. Risk factors include graft versus host disease and pre-transplant seropositivity to adenovirus. Standard treatment of this disorder consists of hydration, diuresis and analgesics. Failure of these measures leads to multiple blood transfusions, severe patient morbidity and possible death. When conservative therapy is unsuccessful, there is no proved standard of care. We recently used ribavirin, a broad-spectrum antiviral agent against adenovirus infection in vitro, to treat refractory adenovirus hemorrhagic cystitis after bone marrow transplantation. The hematuria and urinary symptomatology resolved without demonstrable side effects. We present ribavirin as a therapeutic alternative when conservative treatment for adenovirus hemorrhagic cystitis fails.

Adenovirus Infections, Human↗
PubMed1993

Epiligrin, a component of epithelial basement membranes, is an adhesive ligand for alpha 3 beta 1 positive T lymphocytes.

The cutaneous T cell lymphomas (CTCL), typified by mycosis fungoides, and several chronic T cell mediated dermatoses are characterized by the migration of T lymphocytes into the epidermis (epidermotropism). Alternatively, other types of cutaneous inflammation (malignant cutaneous B cell lymphoma, CBCL, or lymphocytoma cutis, non-malignant T or B cell type) do not show evidence of epidermotropism. This suggests that certain T lymphocyte subpopulations are able to interact with and penetrate the epidermal basement membrane. We show here that T lymphocytes derived from patients with CTCL (HUT 78 or HUT 102 cells), adhere to the detergent-insoluble extracellular matrix prepared from cultured basal keratinocytes (HFK ECM). HUT cell adhesion to HFK ECM was inhibitable with monoclonal antibodies (mAbs) directed to the alpha 3 (P1B5) or beta 1 (P4C10) integrin receptors, and could be up-regulated by an activating anti-beta 1 mAb (P4G11). An inhibitory mAb, P3H9-2, raised against keratinocytes identified epiligrin as the ligand for alpha 3 beta 1 positive T cells in HFK ECM. Interestingly, two lymphocyte populations could be clearly distinguished relative to expression of alpha 3 beta 1 by flow cytometry analysis. Lymphokine activated killer cells, alloreactive cytotoxic T cells and T cells derived from patients with CTCL expressed high levels of alpha 3 beta 1 (alpha 3 beta 1high). Non-adherent peripheral blood mononuclear cells, acute T or B lymphocytic leukemias, or non-cutaneous T or B lymphocyte cell lines expressed low levels of alpha 3 beta 1 (alpha 3 beta 1low). Resting PBL or alpha 3 beta 1low T or B cell lines did not adhere to HFK ECM or purified epiligrin. However, adhesion to epiligrin could be up-regulated by mAbs which activate the beta 1 subunit indicating that alpha 3 beta 1 activity is a function of expression and affinity. In skin derived from patients with graft-vs.-host (GVH) disease, experimentally induced delayed hypersensitivity reactions, and CTCL, the infiltrating T cells could be stained with mAbs to alpha 3 or beta 1 and were localized in close proximity to the epiligrin-containing basement membrane. Infiltrating lymphocytes in malignant cutaneous B disease (CBCL) did not express alpha 3 beta 1 by immunohistochemical techniques and did not associate with the epidermal basement membrane. The present findings clearly define a function for alpha 3 beta 1 in T cells and strongly suggest that alpha 3 beta 1 interaction with epiligrin may be involved in the pathogenesis of cutaneous inflammation.

Basement Membrane↗
PubMed1993

Mast cell degranulation upregulates alpha 6 integrins on epidermal Langerhans cells.

The expression of the alpha 6 beta 4 and alpha 6 beta 1 integrins on epidermal Langerhans cells (LC) before and after mast cell degranulation was studied in cultured human neonatal foreskin by immunohistochemistry. Twenty-four hours after addition of mast cell secretagogues, morphine sulfate, or substance P, solitary mid-epidermal cells showed staining for the integrin subunits alpha 6, beta 4, and beta 1. This expression was not observed in cultured control explants, and immunostained cells were confirmed to be non-epithelial, dendritic cells by immuno-electron microscopy. The identity of these cells as LC was further established by coincident staining for alpha 6 and CD1a using double immunofluorescence labeling. Addition of tumor necrosis factor-alpha (TNF alpha), the predominant cytokine in mast cell granules, also induced LC to express alpha 6 integrins. Furthermore, preincubation of skin organ cultures with anti-TNF alpha antibodies or the mast cell inhibitor cromolyn sodium abrogated the ability to induce alpha 6 integrins on LC consequent to experimental mast cell degranulation by substance P. These data implicate a role for mast cell-derived TNF alpha in the regulation of the integrins alpha 6 beta 4 and alpha 6 beta 1 on LC. These findings may have important implications relevant to mechanisms for spatial localization of LC within the cutaneous compartments during immune responses.

Cell Degranulation↗
PubMed1993

Autologous melanoma vaccine induces inflammatory responses in melanoma metastases: relevance to immunologic regression and immunotherapy.

Human primary malignant melanoma is often accompanied by a host response of infiltrating lymphocytes suggestive of tumor antigen-induced immunity and correlated in some tumors with prognosis. Whereas metastatic melanoma deposits typically are not inflamed and contain relatively few lymphocytes and dendritic immune cells, immunization with autologous melanoma-cell vaccine may induce a clinical inflammatory response associated with mononuclear-cell infiltration. In this study, we characterize immune responses to dermal and subcutaneous melanoma metastases in dinitrophenyl (DNP)-pre-sensitized patients immunized with DNP-conjugated melanoma cells. Patients so treated develop cutaneous delayed hypersensitivity responses to DNP-conjugated autologous mononuclear cells, and approximately one-half show clinical evidence of inflammation and regression of metastases within 2-4 months. Whereas pre-vaccination biopsies of metastatic melanoma failed to reveal significant infiltration by lymphocytes, biopsies obtained after vaccination and coincident with clinical inflammation were markedly infiltrated preponderantly by T cells with a CD8+ phenotype. Clustering of these cells about individual degenerating melanoma cells in a manner analogous to "satellitosis" was a consistent feature of this reaction. Enhanced expression of intercellular adhesion molecule-1 (ICAM-1) and human leukocyte antigen (HLA)-DR by melanoma cells were invariably associated with zones of T-cell infiltration, whereas diminished or absent expression was observed in relatively unaffected regions of tumors. Numerous HLA-DR+, CD4+, CD1-, Leu-1- dendritic cells were also associated with zones of early T-cell infiltration. These data indicate that clinical inflammation and regression of metastatic melanoma induced by autologous melanoma-cell vaccine involves activated T cells with cytotoxic-suppressor phenotype and dendritic cells putatively capable of local antigen presentation. ICAM-1 upregulation on melanoma cells is a likely mediator of ligand interaction between infiltrating T cells and target cells in this model of antigen-induced host anti-tumor response. Structural alterations identified in this setting (e.g., tumor cell satellitosis) may provide additional insight into identifying features of naturally occurring host immune responses to primary cutaneous melanomas.

Dermatitis, Atopic↗
PubMed1993

Painful tumors of the skin.

BACKGROUND: Several cutaneous tumors are characteristically associated with considerable and sometimes incapacitating pain. OBJECTIVE: A review of the histologic features of these tumors, subjective characteristics of the pain, hypotheses proposed to explain the mechanism of pain production by the tumor, and treatments that have been effective in abolishing or relieving the patient's perception of the stimulus. METHODS: Review of case reports as well as studies that have proposed mechanisms of pain production based on histologic, electron microscopic, and pharmacologic studies. RESULTS: Several hypotheses may be equally valid in explaining the cause of pain of a single tumor type, while no apparent cause is found in other types of tumors. There is variability in the success of a treatment between patients. CONCLUSION: Our understanding of the mechanism of pain production by cutaneous tumors is limited by the small number of studies (and sample size) addressing the issue as well as by our incomplete general understanding of pain production.

Humans↗
PubMed1993

Expression of platelet-endothelial cell adhesion molecule-1 (PECAM-1) during melanoma-induced angiogenesis in vivo.

Recent ultrastructural data indicate that tumor-induced angiogenesis involves polarized outgrowth of endothelial cells from established vessels into tumor parenchyma and interstitium. Efforts to define the cytoarchitecture of the angiogenic response and to ascertain molecular determinants of polarized endothelial migration have been impeded by lack of sensitive and specific immunologic markers for endothelium and vessel wall components. In this study, we utilized monoclonal antibody to platelet-endothelial cell adhesion molecule-1 (PECAM-1), a cell-cell adhesion molecule belonging to the immunoglobulin superfamily, to determine extent and patterns of angiogenesis in metastatic melanomas before (N = 7) and after (N = 3) induction of tumor-infiltrating lymphocyte responses provoked by administration of experimental melanoma vaccine. PECAM-1 proved to be a more reliable marker for angiogenesis than antibodies to von Willebrand Factor. Although both normal and tumor vessels exhibited prominent staining for PECAM-1, different patterns of endothelial reactivity were observed. Formation of new vessels was associated with i) PECAM-1 redistribution from a constitutive circumferential membrane pattern to a pattern restricted to cell-cell junctions; ii) formation of endothelial cords formed by cell-cell interactions; and iii) eventual development of open lumens. Vessels within inflamed (vaccine-treated) and non-inflamed melanomas did not differ with regard to patterns of PECAM-1 expression. Forming vessels of inflamed melanomas failed to express the cytokine-inducible activation marker, E-selectin. Although normal microvessels and reactive vessels of healing wounds demonstrated prominent staining for alpha 6 laminin receptor, vessels within melanomas showed apparently diminished expression.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Differential induction of intercellular adhesion molecule-1 in human skin by recombinant cytokines.

We examine the effects of the recombinant epidermal cytokines interleukin 1 alpha (IL-1 alpha), interleukin 1 beta (IL-1 beta), interleukin 3 (IL-3), interleukin 6 (IL-6), granulocyte-macrophage colony stimulating factor (GM-CSF), macrophage colony stimulating factor (M-CSF), tumor necrosis factor alpha (TNF), and the effect of the lymphokine gamma interferon (gamma-IFN) on the expression of ICAM-1 in short term organ cultures of newborn human foreskins. In normal skin, ICAM-1 was detected immunohistochemically exclusively on endothelial cells. In addition to enhanced ICAM-1 expression by endothelial cells (at 1 h) and keratinocytes (by 6 h) exposed to gamma-IFN, increased endothelial cell expression also resulted at 24 h after exposure to IL-6 and GM-CSF and at 48 h to M-CSF. Dermal dendritic cell reactivity for ICAM-1 was observed at 24 h after supplementation with IL-1 alpha, IL-1 beta and IL-6, and at 48 h with GM-CSF and M-CSF. Incubation with culture medium alone or with IL-3 resulted in no change in baseline ICAM-1 expression on any cell type, and incubation with TNF resulted in enhanced ICAM-1 expression only by endothelial cells. Thus, in skin explants (as opposed to isolated cell in culture), ICAM-1 is induced on various cell types by a wide range of epidermal cytokines, including IL-6, GM-CSF, M-CSF, IL-1 alpha and IL-1 beta.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Adhesion Molecules↗
PubMed1993

Human/severe combined immunodeficient mouse chimeras. An experimental in vivo model system to study the regulation of human endothelial cell-leukocyte adhesion molecules.

The ability of circulating white blood cells to enter inflamed tissues is mediated by specific cell adhesion molecules thought to be expressed in a programmed and sequential manner to form an "adhesion cascade." Because of the complexity of this process, it is becoming increasingly important to develop in vivo models. Two major problems have limited the utility of current animal models. The first is the inability of many of the antibodies developed against cell adhesion molecules in human cell culture models to cross-react in animals. The second is the uncertainty in extrapolating animal (particularly rodent) findings to humans. To circumvent these problems, full thickness human skin grafts were transplanted onto immunodeficient (severe combined immunodeficient) mice. After 4-6 wk, the transplanted skin grafts closely resembled normal skin histologically and maintained their human vasculature as determined by immunohistochemical staining with human-specific endothelial cell markers. Intradermal injection of tumor necrosis factor-alpha resulted in the reversible upregulation of the leukocyte-endothelial adhesion molecules E-selectin, vascular cell adhesion molecule-1, and intercellular adhesion molecule-1, and in an active inflammatory reaction with migration of murine leukocytes into cytokine-injected areas. These results indicate that the severe combined immunodeficient mouse/human skin transplant model provides a useful in vivo system in which to study human endothelium during the process of inflammation.

Adult↗