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We measured sICAM-1 in paired samples of serum and cerebrospinal fluid (CSF) from patients with an attack of multiple sclerosis (MS) (n = 50) and patients with acute monosymptomatic optic neuritis (ON) as a possible first attack of MS were also included (n = 25). Based on calculations of extended indices we found evidence of intrathecal synthesis of sICAM-1 both in patients with clinically definite MS and in patients with idiopathic ON compared to neurological control subjects. The amount of intrathecally synthesized sICAM-1 correlated significantly to the CSF leukocyte count and to the concentration of myelin basic protein in the CSF. The serum concentrations of sICAM-1 were not increased in patients with demyelinating disease compared to the neurological control subjects.

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The genes encoding the T-cell receptor (TCR) variable beta (TCRBV) regions were studied in skin biopsy samples from 24 patients with cutaneous T-cell lymphomas (CTCL), i.e. mycosis fungoides (n = 7), Sézary syndrome (n = 4), lymphomatoid papulosis (n = 3) and large cell CTCL with (n = 3) or without (n = 7) CD30 expression. A panel of 24 primers specific for TCRBV families 1-24 was designed and applied to cDNA using a semiquantitative reverse transcriptase coupled polymerase chain reaction (PCR) method. Three patients showed restricted expression of a limited number (1-3) of TCRBV families. In the remaining patients, an average of 17 (range: 13-22) different families was expressed. All patients showed elevated (> 10%) expression of individual families significantly higher than that seen in normal blood lymphocytes, but no preferential usage of particular gene families was observed. Direct sequence analysis of more than 60 PCR products revealed clonal TCR transcripts in 18 patients. A single T-cell clone, constituting 9-100% (mean: 26%) of the TCRBV mRNA, was present in 12 patients; two T-cell clones, constituting 13-72% (mean: 21.5%) of the TCRBV mRNA, were present in five patients; and three T-cell clones, accounting for < 0.5-13% of the TCRBV mRNA, were present in one patient. In the remaining six patients, clonal TCR transcripts could not be identified. It is concluded that most CTCL contain both clonal and non-clonal (reactive) T cells, and that the latter cells are more numerous than anticipated. These cells may be engaged in tumour immune reactions, although prospective studies and/or serial investigations are needed to elucidate this issue fully.

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BACKGROUND: The exacerbation of atopic dermatitis may be associated with infection of the skin with Staphylococcus aureus (S.aureus). S. aureus isolated from the skin of patients with atopic dermatitis secretes enterotoxin A, B, and toxic shock syndrome toxin 1. This is of interest because these patients may develop specific IgE antibodies against components from staphylococci. OBJECTIVE: The objective was to demonstrate IgE-sensitization to components of Staphylococcus aureus enterotoxins A and B (purified and partially purified), toxic shock syndrome toxin 1, and the bacterial cell component lipoteichoic acid, in patients with atopic dermatitis. METHODS: Blood samples from 34 patients with atopic dermatitis and 10 controls were tested by leukocyte histamine release to the enterotoxins and lipoteichoic acid. The toxins were separated by sodium dodecylsulfate polyacrylamide gel electrophoresis and analyzed by IgE-immunoblotting with sera from the same patients. RESULTS: The majority of patients (96%) with clinical signs of skin infection produced specific IgE-antibodies to all three toxins. Nearly half of the patients produced IgE to enterotoxin A and B. Only 63% of the patients with atopic dermatitis showed cellular response judged by the release of histamine from patient basophils when challenged in vitro with the toxins. This may indicate clinically unimportant sensitization in a number of patients. The immunoblotting revealed that the major allergens of the toxins were 24 and 28 kD proteins. Partially purified toxins showed a higher frequency of leukocyte histamine release responses than purified toxin. The only obvious difference was a difference in the content of pure toxin of the two preparations. Lipoteichoic acid showed nonspecific activity. CONCLUSION: These findings suggest that staphylococcal enterotoxins may act as specific allergens and induce IgE-antibodies to enterotoxins that may exacerbate the skin inflammation in some patients with atopic dermatitis.

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Lymphoproliferative disorders are usually characterized by lymphoid infiltrates that demonstrate clonality in contrast to inflammatory or reactive infiltrates of the skin that are polyclonal without detectable monoclonal populations of T-cells. Probably the southern blot analysis of TCR gene rearrangement can help to delineate the reactive from the malignant processes. In this study, we applied the technique on benign reactive processes in the skin. We examined biopsies from positive patch tests from patients with a delayed hypersensitivity reaction. We found the same gene rearrangement configuration in 11 of 17 patients with positive patch tests. The extra band revealed in these cases was situated in the EcoR1 digested DNA lane at the 8.0 Kb, between the 2 germline bands at the 11 Kb and the 4 Kb respectively. This observation was not correlated to the degree of the inflammatory response or to the specific hapten induced reaction. This pattern was not found in any of 107 patients with malignant diagnoses, but also in six of 43 patients with benign diseases. The clinical implication may suggest the presence or development of clonality in benign inflammatory disorders.

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p53 is an oncosuppressor gene located on chromosome 17p. Point mutations of the p53 gene are seen frequently in human malignancies, and are closely associated with malignant transformation under in vitro conditions. Mutated p53 protein shows a slow cell turnover rate, and accumulates in cells at the nuclear and/or cytoplasmic level. As a result, mutated p53 protein can be detected more readily by immunohistology than the wild-type protein. In this study, we used a monoclonal anti-p53 antibody (clone DO7) to examine the expression of p53 protein in 25 cutaneous T-cell lymphomas (CTCL) of low- and high-grade malignancy, i.e. mycosis fungoides (n = 6), Sézary's syndrome (n = 2), and large cell lymphomas of pleomorphic (n = 14) or anaplastic (n = 3) subtype. The results showed that easily detectable p53 protein was present in many of the neoplastic cells in half of the high-grade lymphomas. In contrast, in the low-grade lymphomas no, or only very few, p53-positive neoplastic cells could be detected. These findings suggest that molecular and/or genetic alterations of p53 may be implicated in the pathogenesis of high-grade CTCL, but are unlikely to be of critical importance in low-grade CTCL.

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This paper demonstrates and characterizes naturally occurring antibodies to interferon (IFN) in human IgG preparations. In vitro neutralization of the antiviral effect of IFN alpha and IFN beta, but not IFN gamma, was observed in 12 of 15 normal IgG preparations. The neutralizing capacity was higher against rIFN alpha 2A and rIFN alpha 2C than against lymphoblastoid IFN alpha and IFN beta. Frühsommer meningoencephalitis hyperimmune IgG and hepatitis-B hyperimmune IgG showed potent neutralization, whereas anti-rhesus D-, anti-rabies-, and anti-tetanus IgG showed weak neutralization. Saturable binding of 125I-rIFN alpha 2A was demonstrated only in those IgG preparations found to neutralize the antiviral effect of IFN. Significant correlation between IFN binding and neutralization capacity was observed. The antibodies bound with Fab to rIFN alpha 2A with an avidity of approximately 30 pM; the majority was of the IgG1 subclass. Maximum binding capacity was 490 pg rIFN alpha 2A/mg IgG. Cross-binding of rIFN alpha 2C, lyIFN alpha N1 and IFN beta occurred with 10 and 100-200 times lower activities than that of rIFN alpha 2A. There was no cross-binding with rIFN gamma or rIL-6. IgG preparations containing anti-IFN antibodies blocked the binding of 125I-rIFN alpha 2A to A549 cells. In conclusion, pharmaceutically prepared human IgG preparations contain variable but significant levels of high-avidity IFN alpha and IFN beta neutralizing antibodies.

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Current understanding of the immunological mechanisms involved in the pathogenesis of venous leg ulcers is insufficient. In this study the cellular composition of skin biopsies taken from the center, the edge, and 2 cm distant from the edge of venous leg ulcers was characterized quantitatively by immunohistochemical staining. In the epidermis the mean numbers of Langerhans cells (CD1a+) were four times lower at the edge of the ulcer compared to clinically intact epidermis 2 cm distant from the edge. In the dermis a statistically significant increase in the mean numbers of macrophages (CD68+) and neutrophils (NP57+) from the distant area towards the center of the ulcer was observed. No significant differences were observed in the distribution of T cells nor in the ratio of CD4+/CD8+ T-cell subsets between the different regions of the ulcer. About 30% of T lymphocytes were CD8+ in all microenvironments. The center and the edge of the ulcer were dominated by macrophages comprising 63% and 53% of the cells respectively, while T lymphocytes dominated the distant area. The area 2 cm distant from the edge was also heavily infiltrated by macrophages and neutrophils. B cells (CD22+) and NK cells (CD56+) were relatively rare in all areas, comprising less than 3% of the dermal infiltrate. In conclusion, local microenvironments each with a different cellular composition can be defined within venous leg ulcers.

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In this study we have investigated the configuration of the T-cell receptor (TCR) beta-chain genes in benign cutaneous conditions (n = 5) and known (n = 22) or suspected (n = 5) cutaneous T-cell lymphoma (CTCL). Sequential biopsies from skin, lymph node, blood and/or bone marrow were available in 12 cases of the 22 confirmed CTCL, and a total of 67 samples were analysed. In the benign conditions, clonal rearrangements of the TCR beta-chain genes were seen in neither skin nor blood samples. In contrast, in CTCL clonal rearrangements were detected in all skin samples from plaque or tumour lesions of mycosis fungoides. Clonal TCR rearrangements were also present in skin and blood samples from two patients with Sèzary's syndrome, and in skin and blood samples from three of five patients with clinically suspected CTCL. In 10 patients with large cell lymphomas, clonal rearrangements were detected in skin samples in half of the cases. In the remaining patients, clonal TCR rearrangements could not be detected in the skin, but only in the blood and/or bone marrow specimens. Results from the analyses of sequential biopsies showed identical patterns of rearrangement in 11 patients. In the remaining patient, the pattern of rearrangement differed between skin and lymph node. These data confirm and extend previous reports and indicate that analysis of TCR beta-chain genes by Southern blotting forms a useful supplement to other methods for the diagnosis of known and suspected CTCL. They also emphasize the importance of studying not only skin, but also extracutaneous sites.

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CD1+ antigen-presenting cells in involved epidermis of patients with cutaneous T-cell lymphoma exhibit and enhanced functional capacity to activate autologous CD4+ T cells compared with CD1+ antigen-presenting cells from uninvolved and normal epidermis. Class II major histocompatibility complex molecules are involved in antigen presentation, and their expression on CD1+ Langerhans cells is known to vary. The expression of all three class II (HLA-DR, -DQ, -DP) molecules was therefore determined on CD1+ epidermal cells from both involved and uninvolved epidermis, using flow cytometry. The involved CD1+ epidermal cells exhibited a 1.5-1.6-fold, statistically significant increase in fluorescence intensity after staining of the class II molecules (HLA-DR, -DQ, -DP) compared with CD1+ epidermal cells from uninvolved epidermis. The autologous CD4+ T cells, activation was almost completely blocked by anti-HLA-DR, and partly by anti-HLA-DQ and anti-HLA-DP. In contrast, an antibody against class I, and an irrelevant control antibody, had no blocking effect. In a pokeweed mitogen assay it was demonstrated that autologous CD4+ T cells, activated by involved epidermal cells, demonstrated suppressor activity rather than helper activity. The suppressor activity was dependent on the presence of HLA-DR-positive epidermal cells. Thus, in cutaneous T-cell lymphoma, class II molecules on the individual CD1+ antigen-presenting cell are upregulated in clinically involved compared with uninvolved epidermis, and these molecules are crucially involved in activation of CD4+ T cells.

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Forty-one patients with lymphomatoid papulosis have been followed from 1 to 22 years (mean 11.4 years, median 10 years). Six patients developed malignant lymphoma, 3 cutaneous T-cell lymphoma, 2 Ki-1 large cell lymphoma, and 1 Hodgkin's disease. A clinical malignant presentation combined with the finding of aneuploidy in skin lesions seem to be indications of a malignant potential. Treatment with methotrexate in low dosage is an efficient treatment of lymphomatoid papulosis and probably diminishes the risk of malignancy.

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Subcutaneous insertion of expanded polytetrafluoroethylene tubes with local anesthesia constitutes a minimally invasive model permitting quantitative and qualitative studies of the wound healing potential in human beings. Light and electron microscopic examination of these implants in rats showed a normally appearing granulation tissue. The amount of hydroxyproline accumulated in the expanded polytetrafluoroethylene tubes may be assayed and converted to collagen content. In 28 surgical patients, the collagen content increased from 6.6 microg/cm (interquartile range: 5.1 to 9.9) after 5 days to 12.4 microg/cm (7.1 to 16.8) after 10 days (p < 0.05). The median ratio between the higher and lower collagen amount measured in two expanded polytetrafluoroethylene tubes inserted for an identical period within the same patient was 1.25 (1.10 to 1.81). This variability ratio was not related to the amount of collagen accumulated or the duration of implantation. There was a tendency for higher collagen amounts in the middle section than in the ends of the expanded polytetrafluoroethylene tubes, with a median ratio between the two sections equaling 1.12 (0.96 to 1.58); (p > 0.05). No infectious or hemorrhagic complications from the insertion occurred in any of the patients. Increments of collagen deposition with time may be easily assessed by this expanded polytetrafluoroethylene tube model, which is inexpensive and has high patient acceptance. Measurement variability was encountered, which has to be taken into account when designing clinical trials.

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Examination of biopsies from 62 patients with, or suspected of having cutaneous T-cell lymphoma (CTCL) revealed 24 cases in which the neoplastic cells expressed aberrant or suppressor T-cell phenotypes. The clinical records of these patients were reviewed in an attempt to establish whether recognition of these phenotypes has any clinical implications. Twelve patients had mycosis fungoides (MF) with plaques (n = 4) or tumours (n = 8), four had Sézary syndrome, and eight had large-cell lymphomas of pleomorphic (n = 6) or anaplastic subtype (n = 2). Most of the large-cell lymphomas behaved aggressively, as might have been expected from their cytological appearance. Aggressive courses were also seen in Sézary syndrome, and in tumour lesions of MF, whereas the behaviour in cases of plaque lesions was indolent. Again, this might have been anticipated from the clinical staging and routine histological examination. It is suggested that the expression of aberrant or suppressor T-cell phenotypes in CTCL is not of independent prognostic significance, but that the stage and histology are more important. This issue is an important topic for a prospective analysis.

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In this report we have reviewed studies on the clinical effect of the interferon (IFN) treatment of 304 patients suffering from cutaneous T-cell lymphoma (CTCL). Intramuscular, subcutaneous or intralesional administration of recombinant IFN has been used as monotherapy or as part of combination therapy. In general, IFN has proved to be a relatively effective agent in the treatment of CTCL, and the best responses have been achieved in the early stages of the disease. In CTCL the overall response rate to IFN including complete, partial and minor responses is 70%. Neither the doses nor the routes of administration in these studies has any statistically significant influence on the clinical response to IFN treatment. Continuous low-dose IFN therapy, presumably in combination with psoralen and UVA light (PUVA), is recommended. This review concludes that the clinical stage of disease before treatment is the only known predictive parameter concerning the clinical response to IFN treatment in patients with CTCL.

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Antigen-dependent activation of T cells occurs through the T-cell antigen-receptor complex (TCR/CD3). Antigen-independent T-cell activation may occur through the surface molecules CDw60, CD2, and CD28. We wished to determine whether these antigen-independent T-cell-activation pathways could be involved in proliferation of leukemic T cells from patients with cutaneous T-cell lymphoma (CTCL). Whereas CDw60 was only expressed on 28% +/- 7% (mean +/- SEM) of blood T cells obtained from healthy control subjects (n = 4), CDw60 was expressed on 94% +/- 3% of blood T cells obtained from patients with CTCL (n = 4). Dual color immunofluorescence microscopy of the T-cell infiltrate in involved skin of these patients demonstrated that almost 100% of the T cells expressed CDw60. Not only did T cells in the patients with CTCL express CDw60, but triggering of the T cells with anti-CDw60 resulted in enhanced proliferation relative to anti-TCR/CD3 and mitogenic lectins. Other antigen-independent pathways also appeared highly active in the T cells from patients with CTCL because enhanced proliferation relative to anti-TCR/CD3 or mitogenic lectins was found when anti-CD2 or anti-CD28 plus phorbol ester was used as stimulant. Despite the brisk proliferation induced by anti-CDw60, anti-CD2, or anti-CD28, T cells from the patients did not produce detectable amounts of gamma-interferon. The inability to produce gamma-interferon correlates with our finding of absent (n = 3) or weak (n = 1) intercellular adhesion molecule-1 expression in the lesional keratinocytes in these patients. In conclusion, T cells of patients with CTCL demonstrate elevated expression of a T-cell-independent signaling molecule CDw60 and respond to antigen-independent activating signals.

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Examination of biopsy samples from 62 patients with--or with suspected--cutaneous T-cell lymphoma (CTCL) revealed 2 cases in which the neoplastic cells were positive for the T-cell receptor (TCR) gamma delta complex. One patient had mycosis fungoides and 1 patient had a pleomorphic lymphoma of medium and large-cell type. Both cases showed aggressive courses with dissemination to internal organs and short survival times. The phenotypic examination showed that the neoplastic cells were positive with TCR delta 1, CD3, CD25, CD29, CD45R0 and CD54. No staining was seen with antibodies against framework determinants or variable regions on the TCR alpha beta heterodimer. Negative reactions were also seen with CD4, CD8, CD5, CD7, CD16, CD30 and CD57. It is concluded that rare CTCL express TCR gamma delta chains. These malignancies may originate from the TCR gamma delta-positive T cells seen in normal skin, and it is possible that their recognition may be important for clinical reasons.

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In this study we have tried to take advantage of the high genetic homology between conserved regions of human T-cell lymphotropic virus (HTLV) types I and II, hoping that a possible retrovirus in patients with cutaneous T-cell lymphoma (CTCL) would have regions with homology to types I/II. DNA was extracted from punch skin biopsies from 21 patients and subjected to the polymerase chain reaction (PCR), using primer sets designed to match conserved regions in the HTLV-I/II genome. The PCR products were subjected to agarose gel electrophoresis with subsequent Southern blotting and hybridization to an HTLV-I probe. No bands of exogenous origin were seen on the agarose gel or by hybridization. If a retrovirus is present in the skin in CTCL patients, it is either not related to HTLV-I/II, present at a copy number below the PCR detection limit, or has been cleared from the skin before the clinical symptoms appear.

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The mortality rate of nonmelanoma skin cancer is higher than generally considered. An actual nonmelanoma skin cancer is a risk factor not only for other skin cancers but also for cancers in other organs. The recurrence rate can, according to the method of calculation, yield surprisingly diverging results. Statistical mapping of subclinical tumor growth in basal cell carcinoma supplies the margins for tumor-free excision. An even better but more expensive tool for therapy planning is tumor imaging with magnetic resonance imaging. Psoralen plus ultraviolet light of the A wavelength-treated patients run a dose-dependent risk of developing squamous cell carcinoma of the skin but also cancers in other organs. Human papilloma virus-16 seems not to be associated with squamous cell carcinoma of the skin except for the anogenital region and possibly the finger. The finding of retroviruslike particles in endemic non-acquired immunodeficiency syndrome Kaposi's sarcoma strongly suggests that a virus other than human immunodeficiency virus may play a role in the pathogenesis of this disease.

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Recent studies have suggested that antibodies against the variable (V) regions of the T-cell antigen receptor (TCR) may be used as markers for clonality and malignancy in T-cell infiltrates. We have investigated this by examining biopsy samples from 45 patients with cutaneous T-cell lymphomas (CTCL) for reactivity with seven antibodies against different V-gene families on the TCR alpha/beta heterodimer, i.e. ICI (V beta 5a), W112 (V beta 5b), OT145 (V beta 6a), 16G8 (V beta 8a), S511 (V beta 12a), F1 (V alpha 2a) and LC4 (alpha beta Va). Serial biopsies were available in 13 patients and a total of 62 samples were studied. The neoplastic cells in five cases were positive for either V beta 5 (one case), V beta 6 (one case), V beta 8 (two cases) or V beta 12 (one case). In the remaining 40 cases, no staining was seen of the neoplastic cells. These findings indicate that while antibodies against the TCR V-regions may be used as clonotypic markers for certain T-cell neoplasms, there is as yet not a sufficient number of anti-TCR V-region antibodies available for the routine diagnosis of these conditions.

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