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T H Rea

Publications and source records attributed to T H Rea.

At least 73 records · Page 4Linked to original sources
PubMed1987

Treatment of chronic erythema nodosum leprosum with cyclosporine A produces clinical and immunohistologic remission.

We have treated three leprosy patients suffering from chronic, steroid-dependent erythema nodosum leprosum (ENL) with cyclosporine A (CsA). Excellent results were obtained in two patients. Extra-cutaneous manifestations of the reactional state were completely suppressed, and the development of new skin lesions was sharply curtailed. Immunohistologic abnormalities characteristic of active ENL were corrected. Lymphocyte subpopulations and anti-mycobacterial antibody levels in peripheral blood were unaffected. The third patient showed only a partial response to CsA, but satisfactory blood levels were never obtained in this individual because of dose-related gastrointestinal toxicity. The effectiveness of CsA in the treatment of ENL is consistent with the hypothesis that aberrant activation of a subset of T-helper cells is involved in the pathogenesis of this reaction. CsA may have a role in the treatment of chronic ENL that has failed to respond to conventional therapeutic modalities.

Adult↗
PubMed1986

Effect of cyclosporine A in erythema nodosum leprosum.

Erythema nodosum leprosum (ENL) is a reactional state of lepromatous leprosy in which the loss of suppressor cell function, decrease in suppressor cell numbers, and increase of interleukin 2 production are observed. We reasoned that cyclosporine A (CsA), by opposing these immune responses, could suppress the ENL reaction and restore patients to the quiescent lepromatous state. We tested this hypothesis in vitro by measuring the effect of CsA on M. leprae-triggered suppressor cells. In 24 of 25 patients with ENL, suppressor cell activity was restored by CsA. The target of CsA appeared to be macrophages. These findings are significant in that they provide the first evidence for the potential efficacy of CsA in the treatment of ENL. Preliminary clinical trials indicate a beneficial therapeutic effect associated with increased T suppressor cells in lesions.

Cyclosporins↗
PubMed1986

Suppressor T lymphocytes from lepromatous leprosy skin lesions.

The immune response in leprosy forms a spectrum with lepromatous leprosy patients exhibiting specific unresponsiveness to antigens of Mycobacterium leprae. This unresponsiveness is thought to be related to the prevalence of T8-positive lymphocyte in these lepromatous lesions. To analyze the immunoregulatory function of these T8 cells, we developed simple procedures to extract lymphocytes from skin biopsy specimens of patients with leprosy. These lymphocytes were sorted for T8 and T4 positive cells, and cell lines were established by expansion with interleukin 2 (IL 2) and irradiated feeder cells. All T8 positive lines tested were positive for IL 2 receptors and HLA-DR determinants. These lines were additionally assayed for lepromin-induced suppression of the normal peripheral blood lymphocyte Con A proliferative response. Thirteen of 32 lines from six lepromatous patients showed significant suppressor activity, whereas nine lines from six tuberculoid patients and one line from normal peripheral blood failed to show suppression (p less than 0.001). Taken together, the finding of M. leprae-triggered suppressor cells within lepromatous skin lesions may in part explain the M. leprae unresponsiveness of lepromatous leprosy patients.

Antigens↗
PubMed1986

In situ and in vitro characterization of the cellular immune response in erythema nodosum leprosum.

We sought to evaluate cell-mediated immune responses in erythema nodosum leprosum (ENL), a reactional state occurring in lepromatous leprosy. Skin biopsies from patients with leprosy were studied with monoclonal antibodies against T lymphocyte antigenic determinants, interleukin 2 (IL 2), and IL 2 receptors (Tac) by using immunoperoxidase staining of frozen sections. Peripheral blood lymphocytes from 18 ENL patients were tested in vitro for lepromin-induced suppression of Con A stimulation. Serial studies of seven lepromatous patients who developed ENL during the course of the study showed increases in both the Leu-3a:Leu-2a ratio and the number of IL 2-positive cells. IL 2-positive cells comprised 0.3% of the cells in all of the ENL lesions studied as compared with the 0.03% found in nonreactional lepromatous lesions (P less than 0.001). Lepromin-induced suppression of the Con A response, present in nonreactional lepromatous patients, significantly decreased in patients developing the ENL reaction, but returned after recovery from ENL. These changes in tissues and peripheral blood suggest that the pathogenesis of ENL is related to cell-mediated immune processes. Despite these immunologic changes, however, ENL patients do not recover antigen-specific skin tests or eliminate Mycobacterium leprae.

Antibodies, Monoclonal↗
PubMed1986

Quantitation of the phenolic glycolipid of Mycobacterium leprae and relevance to glycolipid antigenemia in leprosy.

Chemical and immunologic procedures have been developed for quantitation, in the body fluids of patients with leprosy, of phenolic glycolipid I, the major specific antigen of the leprosy bacillus. Serum samples were extracted with CHCl3/CH3OH and fractionated on columns of silicic acid. Thin-layer chromatography with a sensitivity of about 500 ng allowed detection of the glycolipid in untreated lepromatous and borderline patients, and high-pressure liquid chromatography gave a quantitation of 0.8-3.7 micrograms/ml of serum from four patients. An ELISA-inhibition assay with polyclonal antibodies to glycolipid corroborated these figures. Dot-ELISA on nitrocellulose with polyclonal and monoclonal IgG antibodies allowed for much greater sensitivity (500 pg) and semiquantitative evaluation. Small quantities of glycolipid were present in the urine of patients with lepromatous leprosy. In sera obtained from patients undergoing chemotherapy, the amount of glycolipid declined sooner than did titer of antibody. This experimental approach is applicable to diagnosis of leprosy, bacillary quantification, and standardization of skin-test reagents and vaccines.

Animals↗
PubMed1986

Epidermal keratinocyte Ia expression, Langerhans cell hyperplasia and lymphocytic infiltration in skin lesions of leprosy.

Epidermal changes, Ia expression on keratinocytes, Langerhans cell hyperplasia and lymphocyte infiltration were sought in skin lesions of leprosy: 15 borderline tuberculoid (BT), six borderline lepromatous (BL), 17 lepromatous (LL), 13 erythema nodosum leprosum (ENL), six Lucio reactions and nine reversal reactions. All three changes were well developed in BT and reversal reactions. ENL showed well developed keratinocyte Ia and Langerhans cell hyperplasia, but little lymphocytic infiltration. LL and Lucio tissues had some Langerhans cell hyperplasia but little or no keratinocyte Ia or lymphocytic infiltration. BL tissues were so diverse as to suggest two distinct subgroups. These findings are consistent with the hypothesis that keratinocyte Ia expression is an immunohistological sign of a cell-mediated immune (CMI) response. However, the Ia keratinocyte expression found in BL and ENL tissues appears contrary to the undifferentiated macrophages and numerous bacilli found in the lesions. Thus, if a sign of CMI, keratinocyte Ia expression is not a measure of the effectiveness of the response.

Cell Movement↗
PubMed1986

In situ characterization of T lymphocyte subpopulations in leprosy in the mangabey monkey.

Leprosy in the mangabey monkey is an experimental model which is similar both clinically and histologically to human lepromatous leprosy. The immunopathology of these diseases was compared using monoclonal antibodies against T lymphocyte subpopulations in frozen tissue sections with an immunoperoxidase technique. In both mangabey and human lepromatous granulomas OKT4 (or Leu 3a) and Leu 2a cells were scattered among macrophages with greater numbers of Leu 2a as compared with OKT4 (or Leu 3a) cells. The results suggest that from an immunopathological standpoint experimental leprosy in mangabeys will provide a suitable model for the investigation of the pathogenesis of human lepromatous leprosy and for the evaluation of new antileprosy vaccines.

Animals↗
PubMed1985

Serologic survey for markers of hepatitis B infection in dermatologists.

A serologic survey for markers of hepatitis B virus (HBV) infection was conducted in 593 dermatologists. Serologic evidence for previous infection was found in 15.4%, indicating that dermatologists are an at-risk population comparable to many other specialties of medicine. Dermatologists with a history of blood transfusion, tattoo, and homosexuality had an increased prevalence of serologic markers for HBV. The type of practice, extent of surgery, and glove-wearing practices did not correlate with HBV serologic markers.

Adult↗
PubMed1985

In situ localization of T lymphocytes in disseminated coccidioidomycosis.

Immunohistochemical techniques using monoclonal antibodies to T lymphocyte subpopulations were used to characterize further the granulomas of disseminated coccidioidomycosis. Skin biopsy specimens from patients with disseminated coccidioidomycosis were studied and compared with tissues from experimentally infected mice. In human skin biopsy specimens and infected mouse tissues, discrete granulomata were seen in which T lymphocytes formed a peripheral mantle surrounding central aggregates of macrophages. This unusual pattern of granuloma formation may represent an ineffective host response because these individuals are unable to clear their infection. Because of the close similarity of immunopathology in both human and mouse infections, the mouse model should serve as a useful tool in elucidating the factors contributing to ineffective host responses in systemic fungal infections.

Adolescent↗
PubMed1985

Tissue and blood T-lymphocyte subpopulations in erythema nodosum leprosum.

To study T lymphocytes in erythema nodosum leprosum (ENL), monoclonal antibodies were used to identify T-lymphocyte subpopulations in the blood and skin lesions of patients with ENL and patients with nonreactional lepromatous leprosy. The blood of nonreactional lepromatous patients had a lymphopenia and a proportionate reduction in pan T cells, helper-inducer, and suppressor-cytotoxic subsets, but a normal helper-suppressor ratio, as compared with controls. Patients with ENL did not differ significantly from the controls. In skin lesions, an admixture of helper and suppressor phenotypes among foamy histiocytes was found. The ENL tissue had more numerous cells of the helper-inducer phenotype and fewer of the suppressor-cytotoxic phenotype, as compared with nonreaction lepromatous tissues. In 22 patients with simultaneous examination of tissue and blood T-cell subsets, there was no correlation between tissue and blood helper-suppressor ratios, indicating that some sort of selection process brings lymphocytes into tissues from peripheral blood.

Cell Count↗
PubMed1985

In situ characterization of the cellular immune response in American cutaneous leishmaniasis.

American cutaneous leishmaniasis is a spectrum of granulomatous disease caused by related species of an intracellular parasite. The host response in localized cutaneous leishmaniasis (LCL) is effective in that few organisms can be found in tissue lesions. In contrast, diffuse cutaneous leishmaniasis (DCL) patients mount a poor response with numerous parasites present in multiple skin lesions. Immunopathological correlates were sought in LCL and DCL with immunoperoxidase techniques using monoclonal antibodies directed against T lymphocyte subpopulations and interleukin-2 in tissue lesions. Both LCL and DCL granulomas showed a mixture of T lymphocyte subpopulations with the ratio of helper:suppressor phenotypes less than one. This ratio and localization of cells is more similar to the ineffective lepromatous leprosy granuloma than the effective tuberculoid leprosy granuloma. In contrast, interleukin-2 was identified in equivalent numbers of cells in LCL and tuberculoid leprosy, an order of magnitude greater than DCL and lepromatous leprosy lesions. Cells expressing Tac, the receptor for interleukin-2, were present in approximately equal numbers in all disorders. The immunological effectiveness of granulomas appear to related less to the numbers and location of T cell phenotypes than to the functional aspects of these cells, particularly the ability to generate lymphokines.

Granuloma↗
PubMed1985

An in situ immunohistological study of Mitsuda reactions.

In an attempt to further define their immunopathogenesis, the cellular infiltrates of Mitsuda reactions were studied in situ using immunoperoxidase techniques and monoclonal antibodies. Lepromin A-elicited Mitsuda reactions from six patients with borderline tuberculoid leprosy (TT/BT or BT) and three healthy kindred and contacts of lepromatous patients were examined. In the dermis, cells bearing the Leu4 phenotype comprised a mean of 61% of the infiltrate; the Leu3a, 47%; the Leu2a, 17%; anti-IL-2, 0.2%; anti-Tac, 1.5%; and cells bearing the Ia phenotype were virtually universal; OKT6 positive cells were present. The Leu2 phenotype was sequestered to the periphery of epithelioid tubercules. In the epidermis, there were mild, focal lymphocytic infiltrates, hyperplasia of epidermal Langerhans' cells, and well-developed expression of Ia upon nucleated keratinocytes. These findings, when compared with those of a better-defined reaction, tuberculin, are further evidence that the Mitsuda response may be a delayed-type hypersensitivity phenomenon.

Humans↗
PubMed1984

Use of an artificial antigen containing the 3,6-di-O-methyl-beta-D-glucopyranosyl epitope for the serodiagnosis of leprosy.

The coupling of synthetic 3,6-di-O-methyl-beta-D-glucopyranosyl-(1----4)-2,3-di-O-methyl-alpha-L -rhamnopyranose, the hapten determinant of phenolic glycolipid I from Mycobacterium leprae, to bovine serum albumin (BSA) by reductive amination produced the antigen epsilon-N-1-[1-deoxy-2,3-di-O-methyl-4-O-(3',6'-di-O-methyl-beta -D-glucopyranosyl)-rhamnitol]-lysyl-BSA, which proved highly sensitive in ELISA and showed good concordance with the native glycolipid in analysis of serum samples from 223 leprosy patients. Conjugates prepared from 6-O-methyl-beta-D-glucopyranosyl- or beta-D-glucopyranosyl-containing disaccharides were inactive and those containing noncyclic 3,6-di-O-methyl-glucitol showed little activity. Thus 3,6-di-O-methyl-beta-D-glucopyranose in its cyclic hemiacetal form is necessary for binding anti-glycolipid IgM from leprosy patients. Analysis of serum samples from healthy subjects showed a false-positive rate of 2.4% (four of 169) against the glycolipid and 3.6% (six of 169) against the glycoconjugate. Comparable figures for samples of sera of tuberculosis patients were 3.0% (two of 66) and 9.0% (six of 66), respectively. Alternative synthesizing strategies may diminish this cross-reactivity. The prospects of a fully synthetic specific antigen for the worldwide serodiagnosis of leprosy look promising.

Antigens, Bacterial↗
PubMed1984

Demonstration in situ of subsets of T-lymphocytes in sarcoidosis.

Five biopsy specimens of skin, four of lung, and one of a lymph node were taken from nine patients with sarcoidosis. Monoclonal antibodies were applied to frozen sections of the specimens by an immunoperoxidase technique to test for the presence and distribution of subsets of T-lymphocytes. T-cells expressing the suppressor/cytotoxic phenotype were found predominantly in lymphocytic mantles surrounding sarcoidal granulomas, whereas cells displaying the helper/inducer phenotype were distributed diffusely throughout granulomas. The ratio of helper to suppressor phenotypes in cutaneous sarcoidosis was 5.1 +/- 1.8. The microanatomic location of subpopulations of T-lymphocytes may be important in the pathogenesis of the granulomatous response of sarcoidosis.

Antibodies, Monoclonal↗
PubMed1984

Comparison of S-100 and OKT6 antisera in human skin.

The monoclonal antibody OKT6 and antisera against S-100 protein have both been advocated as immunologic markers of Langerhans cells in the skin. S-100 antiserum has an advantage in its ability to stain Langerhans cells in paraffin tissues. In order to evaluate whether these antibodies stain equivalent numbers of Langerhans cells in skin, we compared the staining patterns of S-100 antiserum and OKT6 antibody on biopsy specimens from 40 patients with leprosy using immunoperoxidase techniques. Utilizing OKT6 antibody, greater numbers of positive Langerhans cells were found in the epidermis in tuberculoid leprosy, reversal reaction, and erythema nodosum leprosum than in lepromatous leprosy. However, these differences were not observed with the S-100 antiserum and, overall, fewer cells were found as compared with the OKT6 antibody. In the dermis both antibodies stained "dendritic cells" that were found encircling granulomas in tuberculoid leprosy and reversal reaction. Staining in lepromatous leprosy granulomas, in contrast to the epidermal staining pattern, revealed rare OKT6-positive cells, while S-100 cells were numerous and were more diffusely distributed throughout the granuloma. Our results indicate that antiserum to S-100 protein and OKT6 antibody stain morphologically similar cells (dendritic cells), but do not provide comparable results concerning distribution and frequency of these cells.

Antibodies, Monoclonal↗
PubMed1984

Immunopathologic demonstration of T lymphocyte subpopulations and interleukin 2 in granuloma annulare.

Immunopathologic aspects of granuloma annulare were studied in frozen sections of nine skin biopsy specimens with monoclonal antibodies directed against T lymphocytes, Langerhans' cells, interleukin 2, and interleukin 2 receptors in conjunction with immunoperoxidase techniques. The predominant lymphocyte was an activated T lymphocyte (Leu 1+, HLA-DR+) with an excess of helper/inducer phenotype (Leu 3a+) as compared with suppressor/cytotoxic phenotype (Leu 2a+). Langerhans' cells were increased in the epidermis and numerous OKT6+ cells were observed in the perivascular and granulomatous infiltrate. Both interleukin 2-positive cells and interleukin 2 receptor-positive cells were identified in the dermal lesions according to observed reactivity with the corresponding monoclonal antibodies. These findings suggest that a cell-mediated immune response producing cytokines may be important in the pathogenesis of granuloma annulare. Comparison of these results with skin specimens from patients with sarcoidosis and from a patient with granuloma annulare having some of the histologic features of sarcoidosis, suggests that the cutaneous infiltrate in granuloma annulare represents a response distinct from that of sarcoidosis.

Antibodies, Monoclonal↗
PubMed1984

Kaposi's sarcoma and autoimmune thrombocytopenia.

Outbreaks of Kaposi's sarcoma, opportunistic infections, and autoimmune thrombocytopenia among homosexual men have recently been described. We report here a case with the combination of Kaposi's sarcoma and autoimmune thrombocytopenia. Our patient presented with Kaposi's sarcoma limited to the integument and autoimmune thrombocytopenia diagnosed by elevated platelet bound IgG. Characteristics of immunosuppression included lymphocytopenia and a reversed blood helper:suppressor T lymphocyte ratio. Immunohistochemical evaluation of skin biopsy specimens revealed tumor cells to contain Factor VIII-related antigen (a vascular endothelial cell marker). In addition some tumor cells stained positively with a monoclonal antibody directed against a cytomegalovirus antigen.

Adult↗