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J Longley

Publications and source records attributed to J Longley.

At least 19 recordsLinked to original sources
PubMed2001

Ultraviolet B(UVB)-induced cox-2 expression in murine skin: an immunohistochemical study.

Cyclooxygenase (COX) is the rate-limiting enzyme in the production of prostaglandins from arachidonic acid. This enzyme exists in at least two isoforms, COX-1 and COX-2. COX-1 is constitutively expressed in most tissues and plays various physiological roles. However, COX-2 expression is induced by a variety of agents, which include pro-inflammatory agents and mitogens. Evidence exists to indicate that increased expression of COX-2 occurs in several types of epithelial neoplasms. In this study, we show the effect of chronic exposure of murine skin to carcinogenic UVB on cutaneous COX-2 expression. SKH-1 mice were irradiated with 180 mJ/cm(2) UVB daily for five days a week for periods ranging from 1 to 20 weeks. Nontumor bearing skin areas of irradiated mice, skin of age-matched controls and benign papillomas and malignant tumors were assessed immunohistochemically for COX-2 expression in these mice. No epidermal staining occurred in any of the non-UVB-treated controls throughout the experiment. Epidermal COX-2 expression only occurred in UVB-irradiated mice. After 1 and 5 weeks of irradiation, patchy epidermal staining mostly confined to the granular layer and stratum corneum was observed. At week 9, staining intensity had increased, particularly in the granular layer. At week 13, staining was uniformly seen in all epidermal layers with particular prominence in the basal cell layer underlying areas of visible epidermal hyperplasia. It is of interest that the most intense staining was seen in the perinuclear region of keratinocytes and at the plasma membrane. At week 20, COX-2 staining was predominant in the granular layer, although in some tissue sections, the entire epidermis was positive. In benign papillomas, staining was confined to the superficial layers of the epidermis and in squamous cell carcinomas (SCCs), patchy staining in the granular and spinous layers predominated. In general, COX-2 expression was more intense in well-differentiated SCCs than in papillomas. In summary, our results indicate that COX-2 serves as an early marker of epidermal UVB exposure and its expression increases in benign papillomas and in SCCs. These results suggest that pharmacological intervention using specific COX-2 inhibitors could have anticarcinogenic effects in UVB-induced human skin cancer.

Animals↗
PubMed2001

The clonotypic T cell receptor is a source of tumor-associated antigens in cutaneous T cell lymphoma.

To develop cancer vaccines for the treatment of cutaneous T cell lymphoma (CTCL), immunogenic peptides were identified by two approaches. First, through the use of "reverse immunology" the peptide sequence of the idiotypic region of the beta chain of the T cell receptor (TCR) was determined and a series of overlapping peptides synthesized and tested for CD8 T cell recognition. In two patients, the idiotypic CDR3 region provided immunogenic epitopes that were recognized in a class I-restricted fashion by autologous CD8 T cell lines. In a second strategy, peptides were isolated directly from class I MHC molecules on the CTCL surface and sequenced. A peptide with partial homology to sequences contained in the conserved variable portion of the clonotypic TCR beta chain was recognized as immunogenic by autologous CD8 T cells. Therefore, both approaches demonstrated that the clonotypic TCR in CTCL is a source of immunogenic tumor epitopes. To confirm that recognition of TCR-derived sequences provides immunoprotection against tumor growth, a murine model of T cell lymphoma was studied. The immunogenicity of a thymoma, which lacks cell surface TCR expression, was enhanced by transfection of the beta chain of the TCR. The studies reviewed in this paper demonstrate that the TCR can serve as one source for immunogenic tumor peptides in T cell lymphoma in vitro and in vivo. Presentation of TCR epitopes on dendritic cells that express high levels of MHC, costimulatory, and adhesion molecules may provide an effective means for immunization against T cell malignancy.

Amino Acid Sequence↗
PubMed1997

Psychosocial Aspects of Diabetes: The Diabetologists' Perspective.

Diabetes mellitus is a multisystem disorder characterized by abnormalities in glucose, fat, and protein metabolism. The long-term microvascular complications of diabetes such as retinopathy, nephropathy, and neuropathy are the same in both forms of the disease. In both types of the disease, diabetes education, frequent monitoring of blood glucose, and regular screening to detect and treat complications at an early stage are an integral part of diabetes management. Patients have to emotionally accept the diagnosis of diabetes and also face the fact that they may already have potentially debilitating complications. Lack of compliance by patients may be a sign of frustration; it signals that goals of treatment and the approach to therapy should be reevaluated. This evaluation should include attention to possible social and psychological issues that may not be immediately apparent. These issues include fear of diabetes and its complications, stress with family or in the workplace and underlying psychiatric conditions. Conversely, both hyperglycemia and hypoglycemia can be very stressful. The relationship between stress and blood glucose control is further complicated by the fact that patients under psychological stress often change their behavior in ways that impact on glucose control. Despite the tremendous progress already made in our understanding of pathophysiology of diabetes and treatment of hyperglycemia, one thing remains unchanged. Life with diabetes continues to be a significant effort and often an overwhelming burden. The disease is complicated, treatments can be complex and prescriptions for patient regimens are often confusing. Diabetes treatment is dependent to a large extent on the individual's ability to practice adequate daily self care, a skill that requires critical support by the health care team. A multidisciplinary approach that includes professionals experienced in psychosocial problems is invaluable in helping these patients.

Journal Article↗
PubMed1996

The immune response to class I-associated tumor-specific cutaneous T-cell lymphoma antigens.

In order to determine whether the neoplastic T cells from patients with cutaneous T-cell lymphoma express tumor-specific antigens that can serve as the targets of an immune response, we took advantage of family-specific monoclonal antibodies, magnetic bead technology, and recombinant cytokines, which provided the previously precluded ability to isolate and expand populations of purified tumor and autologous CD8 cytotoxic T cells. Four patients with advanced cutaneous T-cell lymphoma had CD8 cells that specifically killed autologous tumor in a class I limited fashion. Tumor cell cytolysis could be specifically enhanced by pre-culture with autologous gamma-irradiated tumor. The cytolytic T cells produced tumor necrosis factor-alpha in response to stimulation with autologous tumor. The presence of tumor-specific cytotoxic T cells recognizing distinctive class I associated molecules on cutaneous T-cell lymphoma tumor cells suggests that infiltration of early lesions by CD8 cells reflects host immunity to the neoplasm. These studies provide the foundation for the development of tumor vaccines through the use of cytotoxic T cells to isolate and characterize tumor-associated cutaneous T-cell lymphoma peptides.

Antibody Formation↗
PubMed1995

The mast cell and mast cell disease.

Mast cell disease or mastocytosis is a heterogeneous group of clinical disorders characterized by the proliferation and accumulation of mast cells in a variety of tissues, most often the skin. The signs and symptoms of mast cell disease are varied, dependent on the localization of mast cells in different organs and the local and systemic effects of mediators released from these cells. Although mast cell disease is most commonly identified in the skin, involvement of the skeletal, hematopoietic, gastrointestinal, cardiopulmonary, and central nervous systems may be seen. Clinical management of mastocytosis depends most heavily on knowledge of the diverse effects of mast cell mediators on various tissues and organs, the stimuli that can cause their release, and the different methods available for blocking the effects of these mediators.

Bone Diseases↗
PubMed1995

Detection of specific mRNAs in routinely processed dermatopathology specimens.

To determine the effect of different fixatives on the recovery and detection of mRNAs from archival histopathology specimens, biopsies of normal skin were fixed in neutral and alcohol-buffered formalin, acetone, Carnoy's fixative, methacarn, and Bouin's solution. Tissue was routinely processed, and sections were either mounted for in situ hybridization or deparaffinized for RNA extraction. Extracted mRNA was reverse-transcribed using random hexamers, and the resulting cDNA was amplified by the polymerase chain reaction using primers specific for glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and beta-actin. Amplification products of both GAPDH and actin could be detected by gel electrophoresis from tissues processed in all fixatives except Bouin's. A parallel study of formalin-fixed, paraffin-embedded archival biopsies accessioned since 1990 gave similar results. Less abundant mRNAs, such as those encoding interleukin-11 or the T-cell receptor beta-chain, could be detected by Southern blotting and hybridization with labeled oligonucleotide probes or by cloning and sequencing. In situ hybridization studies using oligonucleotide probes were most successful with tissue fixed in formalin, including both the experimentally fixed tissues and the archival biopsy samples. Thus, mRNAs may be isolated from and localized in formalin-fixed, paraffin-embedded archival material. Because dermatopathology laboratory archives typically contain samples from a wide spectrum of diseases that can be accessed without Human Investigation Committee approval, these laboratories represent a logical starting point for studying gene regulation and expression in skin.

Acetates↗
PubMed1995

Malignant and normal T cells show random use of T-cell receptor alpha chain variable regions in patients with cutaneous T-cell lymphoma.

Cutaneous T-cell lymphoma (CTCL) is a malignancy of mature T lymphocytes, most of which express alpha/beta type T-cell receptors (TCRs). The cause of CTCL is unknown, but hypotheses postulating chronic stimulation of TCRs by superantigen or by a leukemogenic virus have been proposed. Either mechanism might produce bias in the TCR variable (V) region types used by the malignant cells. To determine if TCR alpha use is restricted in CTCL, we used reverse transcription and the polymerase chain reaction to determine V alpha and V beta usage by malignant cells purified from the peripheral blood of leukemic patients with CTCL. Usage of alpha chain V region segments appeared totally random; malignant lymphocytes isolated from each of six patients used different V alpha regions. As has been previously reported, no bias was found in beta chain V region usage either. In addition to productive (in frame) TCR V region mRNAs in malignant cells from each patient, we detected non-productive (out of frame) beta chain transcripts in these cells in two of six patients, and non-productive alpha chain transcripts in five of six. Residual normal peripheral blood lymphocytes from these patients showed a random, polyclonal or oligoclonal pattern of V region usage. We conclude that there is no bias in V region usage in CTCL, making it unlikely that interactions between superantigen or virus and the TCR V regions play a role in the pathogenesis of CTCL.

Aged↗
PubMed1995

Human dermal endothelial cells express membrane-associated mast cell growth factor.

Mast cell growth factor (MGF), a molecule that serves as a ligand for the receptor tyrosine kinase c-kit, is important in mast cell differentiation, migration, and activation. Previous studies of paraffin-embedded human skin using antibody to murine MGF and reverse transcription-polymerase chain reaction have demonstrated MGF protein and mRNA expression in keratinocytes and isolated dermal cells. We utilized a monoclonal antibody to human MGF to further define patterns of immunoreactivity in frozen specimens of neonatal and adult skin from normal individuals and from patients with urticaria pigmentosa. In addition to keratinocytes and isolated dermal cells in normal and urticaria pigmentosa skin, MGF was detected in cells lining superficial and mid-dermal vessels. Co-expression of MGF and the vascular antigen CD31, and immunoelectron microscopy, identified MGF-positive cells as endothelial cells. Patterns of endothelial MGF expression were not influenced by mast cell degranulation and endothelial E-selectin induction in vitro. By ultrastructure, unfixed specimens demonstrated MGF expression both within the endothelial cytoplasm and in association with lumenal, but not ablumenal, surfaces. Specimens fixed with Nakane's solution had diminished endothelial cytoplasmic MGF reactivity, but lumenal expression was maintained, suggesting persistence of a membrane-associated reactivity. MGF mRNA was also detected in cultured dermal microvascular endothelial cells using reverse transcription-polymerase chain reaction. These data establish human dermal endothelial cells as sites of MGF production and expression in human skin. Mast cell precursors must home to skin via vascular channels and differentiate in the immediate perivascular space. Thus, endothelial MGF may be an important determinant of adhesion and differentiation of mast cell progenitors expressing receptors for MGF.

Adult↗
PubMed1995

Regulation of transgenic class II major histocompatibility genes in murine Langerhans cells.

I-E is a class II major histocompatibility complex molecule normally expressed by Langerhans cells. A series of transgenic mice were developed previously that carry E alpha d gene constructs with promoter-region deletions that cause expression of I-E by different cell types when maintained on a B6 (I-E[-]) genetic background. To study cis-acting gene sequences that regulate expression of class II proteins by Langerhans cells, we identified transgenic I-E expression by tissue immunoperoxidase staining and by epidermal cell suspension immunofluorescence cytometry. Mice with a transgene containing 1.4 kilobase pairs (kb) of flanking sequence 5' to the E alpha initiation site expressed barely detectable levels of I-E on a tiny percentage of Langerhans cells, indicating that sequences promoting Langerhans cell expression of E alpha exist between 2.0 and 1.4 kb 5' of the E alpha initiation site. Removal of an additional 170 bp of 5' flanking sequence caused near-normal levels of expression by approximately one third of epidermal Langerhans cells, which contrasts with studies that showed minimal transgene expression by splenic dendritic cells in these animals. Thus, sequences between 1.4 and 1.23 kb 5' of the E alpha initiation site decrease expression of I-E by epidermal Langerhans cells, but enable I-E expression by splenic dendritic cells. These studies identify Langerhans cell-specific regulatory sequences and genetic regions controlling major histocompatibility complex class II gene expression in Langerhans cells and splenic dendritic cells. The genetic regions identified may be particularly important because differential regulation of class II major histocompatibility complex protein synthesis by Langerhans cells and dendritic cells may be crucial to immune functions of intact animals.

Animals↗
PubMed1995

Inflammatory cutaneous metastases from cloacogenic carcinoma of the anus.

BACKGROUND: There are a few tumors that exhibit inflammatory cutaneous metastases. This pattern is particularly difficult to diagnose since it can mimic erysipelas or lymphangitis. OBJECTIVE: This is a presentation of a 69-year-old woman diagnosed with poorly differentiated cloacogenic carcinoma who simultaneously was noted to have an abdominal rash. A biopsy confirmed cutaneous metastasis of her carcinoma. METHODS: Previously published literature on cutaneous metastases were reviewed and summarized. RESULTS: This is the first reported case of an inflammatory cutaneous metastasis arising from cloacogenic carcinoma. CONCLUSION: Cutaneous metastases can present in various forms, including the inflammatory pattern. Because this form mimics other conditions, it is prudent to biopsy any suspicious skin lesion in cancer patients, as it may considerably affect prognosis.

Aged↗
PubMed1993

Clonal deletion of V beta 5+ T cells by transgenic I-E restricted to thymic medullary epithelium.

A variety of cell types expressing MHC class II molecules is known to function as APC in vitro. We employed the Ig kappa gene enhancer and promoter to target the class II E alpha gene, and thereby I-E, exclusively to B cells to address their APC function in vivo. Although transgenic I-E was expressed on B lymphocytes, we unexpectedly obtained I-E on thymic medullary epithelium but not macrophages and at low frequency on dendritic cells. Using these transgenic mice, we constructed bone marrow irradiation chimeras with I-E expressed only on medullary epithelium, in order to determine the role of this cell type in tolerance by clonal deletion in the thymus. Although it is accepted that bm-derived cells play a primary role in deletion, and thymic epithelium can delete clones to a lesser degree, the role of cortical vs medullary thymic epithelium has not been directly dissected. We demonstrate that medullary epithelium alone can tolerize by partial deletion of I-E-reactive V beta 5+ T cells. These results indicate a role for medullary epithelium in deletion during the later stages of thymic development, and support the notion that positive and negative selection of developing T cells can occur in distinct temporal and anatomic compartments.

Animals↗
PubMed1991

Isolation, detection, and amplification of intact mRNA from dermatome strips, epidermal sheets, and sorted epidermal cells.

Three different strategies for isolating RNA from epidermal cells were compared. Starting with dermatome sections frozen or disaggregated epidermal cells purified by fluorescence activated cell sorting (FACS), RNA was isolated with a guanidinium thiocyanate technique. Specific mRNA were detected by Northern blot analysis (involucrin, keratin 5, actin), or by reverse transcription and amplification with the polymerase chain reaction (PCR), using primers specific for keratinocyte products (keratins 1 and 14) and Langerhans cells (CD1a). Messenger RNA's characteristic of Langerhans cells and of keratinocytes at different stages of differentiation were detected in dermatome and epidermal sheet preparations as well as in FACS-separated cells. The use of snap-frozen dermatome sections allows the isolation of RNA from epidermis that has undergone minimal trauma and is very close to its in vivo state, but that includes RNA from some dermal cells. Extraction of RNA from Dispase-separated sheets involves slightly more manipulation of the epidermis but provides a sample free from dermal contaminants. PCR analysis of sorted epidermal cells is both sensitive and specific, but involves still greater manipulation. This final technique, however, allows the investigation of mRNA produced by small groups of epidermal cells that are still much closer to their in vivo state than if they had been cultured. By combining these techniques it is possible to determine the baseline production of specific mRNA in the skin in vivo and to assign their production to specific groups of cells with a sensitivity and specificity greater than any approach previously described.

Base Sequence↗
PubMed1991

[In situ transcription and determination of mRNA in human thymic antigen 1a positive cells within epidermis].

This paper introduces a method of study on the characteristics of cell surface protein. We used human thymic antigen 1a anti-sense oligonucleotide primer, radiolabeled deoxynucleotide and in situ transcription with cells. The results of in situ transcription and determination of mRNA in CD1a positive cells isolated from the epidermis of the prepuce of normal neonate showed that most of the positive cells contained specific CD1a mRNA, and the specificity and sensitivity of this method were higher and the procedure was relatively simple.

Antigens, CD1↗
PubMed1990

Granulocyte macrophage--colony-stimulating factor (GM-CSF) decreases CD1a expression by human Langerhans cells and increases proliferation in the mixed epidermal cell-lymphocyte reaction (MELR).

Langerhans cells (LC) undergo a variety of phenotypic and functional changes in vitro. To determine the effects of granulocyte macrophage--colony-stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-alpha), and interleukin 1-alpha (IL-1) on LC phenotype in vitro, epidermal cell suspensions were enriched for LC by density-gradient centrifugation and cultured in the presence of 10 ng/ml of these cytokines. The percentage of cells expressing the surface protein CD1a was determined by flow cytometry. This percentage typically dropped after 48 h culture in both control and cytokine-treated medium to less than half that of the starting value. By the fifth day, the percentage of cells expressing CD1a in TNF-alpha and IL-1--treated cultures was still near half of the starting value, slightly above that of control cultures. Treatment with GM-CSF caused large and consistent decreases in the percentage of epidermal cells expressing CD1a. Cell viability in each of the three cytokine-treated cultures was identical to the control cultures, with essentially all cells having died by the sixth day after isolation. To determine the functional effects of these cytokines, the cytokine-containing medium was replaced after 72 h with medium containing purified allogeneic T cells and proliferation measured. Preliminary experiments showed no increased proliferation induced by IL-1 or TNF-alpha--treated epidermal cells. GM-CSF-treated epidermal cells induced 2-3 times more T-cell proliferation than epidermal cells cultured without additional cytokines. We conclude that GM-CSF, a cytokine known to be produced by keratinocytes in vitro, decreases CD1a expression by human LC and increases their ability to stimulate proliferation by allogeneic T cells.

Antigens, CD1↗
PubMed1989

Malignant mesothelioma: diagnosis by skin biopsy.

We report a case of malignant mesothelioma in which the tissue diagnosis was established by examination of a skin biopsy specimen. We also review the cutaneous manifestations of malignant mesothelioma. To our knowledge this is only the second reported case diagnosed primarily by examination of tissue from the skin.

Abdominal Muscles↗