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Biomedical subjects

H H Peter

Publications and source records attributed to H H Peter.

At least 55 records · Page 3Linked to original sources

Successful IL-2 therapy for relapsing herpes zoster infection in a patient with idiopathic CD4+ T lymphocytopenia.

Idiopathic CD4+ T lymphocytopenia (ICL) has been defined by the center of disease control as a rare cause of immunodeficiency with a variable clinical course and an unknown aetiology. Here we describe a 65-year old patient with relapsing generalized herpes zoster infection due to ICL and a severe panlymphocytopenia. In vitro assays revealed an enhanced activation of CD8+ T cells and an increased sensitivity of activated CD4+ T cells for cell death. The clinical outcome was substantially improved after starting the patient on a subcutaneous therapy with IL-2.

Adult↗

Different regulation of factor H and FHL-1/reconectin by inflammatory mediators and expression of the two proteins in rheumatoid arthritis (RA).

Factor H and the FHL-1/reconectin protein are two human plasma proteins that act as important regulators of the alternative complement pathway. Each protein is encoded by a unique transcript, but both mRNAs are derived from the factor H gene by means of alternative processing. In order to address potential functional differences between the two proteins we analysed their expression in hepatic and non-hepatic cells and studied their regulation by inflammatory mediators. We demonstrate that factor H and FHL-1/reconectin transcripts which are regulated by the same gene promoter and are initiated at the same transcription start site are differently expressed. Expression of the molecules is induced and regulated by the inflammatory mediators interferon-gamma (IFN-gamma) and the anti-inflammatory glucocorticoid dexamethasone. Both factor H and FHL-1/reconectin are expressed and secreted by synovial fibroblasts and are present in synovial fluid derived from patients suffering from rheumatoid or reactive arthritis. The local synthesis in synovial fibroblasts and their induction by IFN-gamma and dexamethasone, but not by tumour necrosis factor-alpha, suggests for each of the two complement regulators a protective role in RA.

Alternative Splicing↗

Reduced expression of the complement receptor type 2 (CR2, CD21) by synovial fluid B and T lymphocytes.

The expression of CR2 (CD21) by synovial B and T lymphocytes of patients suffering from various forms of arthritis was analysed with cytofluorometry and with reverse transcriptase-polymerase chain reaction. CR2 (CD21) cell surface protein was detected in normal quantities on peripheral B cells, but was almost absent on synovial B lymphocytes of the same patients. This reduction was most severe in patients with rheumatoid arthritis, but also observed in all other cases. CR2 (CD21) did not reappear after in vitro culture. CR2 (CD21) mRNA was also strongly reduced in synovial B and T lymphocytes. Synovial fluid B lymphocytes were larger than peripheral blood B lymphocytes, while T cells from the same patients showed no size differences. We conclude that synovial fluid B lymphocytes have undergone an irreversible step towards terminal differentiation. The presence or absence of CR2 (CD21) mRNA in peripheral versus synovial T cells indicates that CR2 (CD21) is also differentially expressed by T lymphocytes.

Adult↗

Comparison of fresh frozen plasma with a standardized serum protein solution following therapeutic plasma exchange in patients with autoimmune disease: a prospective controlled clinical trial.

The aim of the study was the comparison of the influence of fresh frozen plasma (FFP) (Freiburg, Germany) and Biseko, Biotest Pharma GmbH (Dreieich, Germany), as a plasma substitute (a standardized, virus inactivated human serum protein solution) on the coagulation factors, inhibitors, proteins, and complement factors in the plasma of autoimmune disease patients following membrane plasma separation. Patients (n = 24) with autoimmune disease were randomized to receive either FFP or Biseko for membrane plasma separation therapy. During each plasma exchange, 100% of the plasma volume was replaced by the respective substitute. Plasma exchange volume was performed once daily for 3 days. Target test parameters of the coagulation system were fibrinogen, fibrinopeptide A, factor VIII (FVIIIC), von Willebrand factor antigen (vWFAg), partial thromboplastin time (PTT), thromboplastin time (Quick value), and antithrombin (AT III). The immunoglobulins were IgG, IgA, and IgM and C-reactive protein (CRP). The thrombocytes were platelet factor 4 (PF4), and complement factors were C3 and C4. Biseko was well tolerated with 1 mild adverse drug reaction (ADR) (n = 1) while FFP gave rise to ADR on 7 occasions (n = 4). Statistically significant differences in the 2 groups were observed for fibrinogen, PTT, Quick value, and AT III. From the clinical point of view, all fluctuations and differences in parameter levels remained clinically silent. The differences had no clinical consequences. Reflecting on a potential decrease in the risk of infections in comparison to FFP therapy and the lower rate of adverse drug reactions, it is possible to postulate an advantage of Biseko for plasma exchange therapy.

Adult↗

Efficacy and tolerability of tropisetron in primary fibromyalgia--a highly selective and competitive 5-HT3 receptor antagonist. German Fibromyalgia Study Group.

OBJECTIVE: Based on a potential role for serotonin receptors in fibromyalgia, we investigated the efficacy and tolerability of treatment with tropisetron, a highly selective, competitive inhibitor of the 5-HT3 receptor. METHODS: In this prospective, multicenter, double-blind, parallel-group, dose-finding study, 418 patients suffering from primary fibromyalgia (ACR criteria) were randomly assigned to receive either placebo, 5 mg, 10 mg or 15 mg tropisetron once daily, respectively. The duration of treatment was 10 days. The clinical response was measured by changes in pain-score, visual analog scale (VAS), and the number of painful tender-points. RESULTS: Treatment with 5 mg tropisetron resulted in a significantly higher response rate (39.2%) when compared with placebo (26.2%) (p=0.033). The absolute reduction in pain-score was -13.5% for 5 mg tropisetron, -13.0% for 10 mg tropisetron, and -6.3% for placebo (p<0.05). The effects of 15 mg tropisetron were similar to placebo, thus suggesting a bell-shaped dose-response curve. Compared with placebo, treatment with 5 mg tropisetron led to a significant improvement (p<0.05) in VAS, while a clear trend in terms of clinical benefit was seen with 10 mg tropisetron. The number of painful tender-points was also reduced significantly (p=0.002) in the 5 mg tropisetron group. Of interest, during the 12-month follow-up period, pain intensity of responders on 5 mg and 10 mg tropisetron was still markedly below baseline. The treatment was well tolerated, with gastro-intestinal complaints being the most frequently reported side effects, in keeping with the known safety profile for 5-HT3 receptor antagonists. CONCLUSIONS: This study demonstrates the efficacy of short-term treatment with 5 mg tropisetron once daily in primary fibromyalgia. Treatment was well tolerated and prolonged clinical benefits were seen.

Adolescent↗

Giant cell arteritis is more prevalent in urban than in rural populations: results of an epidemiological study of primary systemic vasculitides in Germany.

OBJECTIVE: To investigate the period prevalences of primary systemic vasculitides (PSV) in urban and rural populations in northern and southern Germany in 1994. METHODS: Questionnaires were sent to all hospital departments, all physicians, health insurance providers and pension funds, reference laboratories for autoimmune diseases, and death registries in two catchment areas in northern and southern Germany (combined population 875 983) to identify patients with PSV between 1 January and 31 December 1994. Each catchment area encompassed both an urban and a rural area. Each case was re-evaluated by the authors by applying the definitions of the 1992 Chapel Hill Consensus Conference on the Nomenclature of Systemic Vasculitis. RESULTS: A total of 180 PSV patients were identified. The overall prevalence of PSV was 216 cases per 1 000 000 inhabitants (95% confidence interval (CI) 173-259) in northern Germany vs 195 (95% CI 153-236) in southern Germany. The prevalence of PSV was two-fold higher in women than in men, and five-fold higher in people aged > or =50 yr than in people aged <50 yr. The most frequent type of PSV was giant cell arteritis (GCA), with 87 cases per 1 000 000 in northern and 94 in southern Germany, followed by Wegener's granulomatosis, with 58 and 42 cases respectively. In the population aged > or =50 yr the prevalence of GCA was 240 per 1 000 000 in northern and 300 in southern Germany. In both northern and southern Germany the prevalence of GCA in this older population was significantly higher in urban than in rural populations (355 per 1 000 000 vs 115 in northern Germany (P<0.01) and 395 vs 220 (P<0.05) in southern Germany). The relative risk for the older urban population having GCA was 2.25-fold higher (95% CI 1.4-3.6) than in the rural population, and for the female population it was 4.7-fold higher in the urban than in the rural areas (95% CI 2.4-9.3). CONCLUSION: In both northern and southern Germany, GCA was significantly more prevalent in urban than in rural populations, especially among people aged > or =50 yr and in women. It remains unclear whether this disparity was due to underdiagnosis of GCA in the rural regions associated with differences in the German health-care system in cities vs rural areas. Further studies must examine the role of (chronic) exposure to the environmental factors characteristic of cities.

Adolescent↗

Diagnosis and monitoring of central nervous system involvement in systemic lupus erythematosus: value of F-18 fluorodeoxyglucose PET.

OBJECTIVE: To investigate prospectively abnormalities of brain glucose utilisation in relation to major or minor neuropsychiatric symptoms in systemic lupus erythematosus (SLE). METHODS: Positron emission tomography (PET) using F-18-labelled fluorodeoxyglucose was performed in 28 patients with SLE. Patients were classified as having severe neuropsychiatric manifestations (seizures, focal neurological deficits, acute confusional states, mood disorders) (n=12), or mild neuropsychiatric manifestations (headache, reactive depression, cognitive dysfunction, anxiety disorders) (n=11) and five patients without signs of central nervous system (CNS) involvement. Ten clinically and neurologically healthy volunteers served as controls. In 26 patients magnetic resonance imaging (MRI) was performed and autoantibodies against CNS tissue, ribosomal P protein and cardiolipin were measured. In 14 patients follow up PET scans were performed after a mean (SD) period of 11.6 (9.5) months. RESULTS: PET scans showed hypometabolism in at least one brain region in all patients with severe or mild CNS symptoms (100%) as compared with patients without cerebral symptoms (40%) (p<0.0025). Parieto-occipital regions were most commonly affected (96%), followed by parietal regions (32%). In contrast, MRI images were abnormal in only 11 of 22 patients (50%) with neuropsychiatric symptoms and in one of four patients (25%) without symptoms. In 12 of 14 patients examined in follow up PET scans persistence, improvement or worsening of cerebral symptoms were associated with unchanged, decreased or increased brain hypometabolism, respectively. No significant correlation was found between PET or MRI findings and autoantibody profiles. CONCLUSIONS: PET imaging represents a sensitive tool to detect manifest or subclinical CNS involvement in SLE and PET findings correlate well with the clinical course of disease.

Adolescent↗

Alterations of cerebral glucose metabolism indicate progress to severe morphological brain lesions in neuropsychiatric systemic lupus erythematosus.

Neuropsychiatric systemic lupus erythematosus (SLE) is frequently associated with deficits in brain glucose metabolism, even if morphological imaging by magnetic resonance imaging (MRI) shows no abnormalities. In these patients it is unclear whether or not the changes of brain metabolism measured by F-18-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) may progress to lesions of cerebral structure. We describe a 20-year-old woman with SLE who presented with depression, headache and impairment of memory. Initially, a cranial MRI was negative, but FDG-PET revealed significant hypometabolism in the frontal and parieto-temporo-occipital regions on both sides as well as hypermetabolism in the nuclei caudati. Within two months the patient developed an acute confusional state, seizures, visual disturbances and cranial MRI became positive showing hyperintensities at the basal ganglia and the temporo-occipital regions. Focal cerebral symptoms responded to treatment with high dose corticosteroids and brain lesions in MRI disappeared. However, a second FDG-PET showed persistent hypometabolism at frontal regions in accordance with the persistence of subclinical depression. To our knowledge, this is the first SLE case report showing that functional brain lesions visualized by FDG-PET may be a risk factor for subsequent structural brain damage seen in MRI. Thus, FDG-PET may help to verify cerebral involvement of SLE earlier than MRI.

Adult↗

IgA and IgG autoantibodies against alpha-fodrin as markers for Sjögren's syndrome. Systemic lupus erythematosus.

OBJECTIVE: To determine the prevalence of IgA and IgG autoantibodies against alpha-fodrin in patients with primary and secondary Sjögren's syndrome (SS) and controls. METHODS: An ELISA detecting IgA and IgG antibodies against alpha-fodrin was developed. We examined the prevalence of IgA and IgG antibodies against alpha-fodrin in patients with primary and secondary SS, systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA) and blood donors. RESULTS: IgA antibodies against alpha-fodrin were detected in 64% of patients with primary SS (n = 85), 47% of patients with secondary SS and SLE (n = 15), and 86% of patients with secondary SS and RA (n = 7). IgA autoantibodies against alpha-fodrin were detected in only one of 160 sera obtained from blood donors and in one of 50 and 2 of 12 sera obtained from SLE and RA patients without sicca syndrome, respectively. The prevalence of IgG antibodies against alpha-fodrin in SS was lower: they were detected in 55% of sera obtained from patients with primary SS, 40% of patients with secondary SS and SLE, and in 43% of patients with secondary SS and RA. Three of 160 sera from blood donors and one of 50 and 5 of 12 sera from SLE and RA patients without sicca syndrome, respectively, contained IgG antibodies against alpha-fodrin. CONCLUSION: IgA rather than IgG antibodies against alpha-fodrin are specific for and frequently observed in primary and secondary SS and are useful markers for this autoimmune disorder.

Adult↗

Synovial PMN show a coordinated up-regulation of CD66 molecules.

Changes in the expression of various activation-dependent surface markers have been reported for polymorphonuclear neutrophils (PMN) isolated from synovial fluid of patients with inflammatory joint diseases. We extend these findings to the expression of CD66 molecules and several other surface markers. Three members of the CD66 family, namely CD66a, CD66b, and CD66c, showed an up to fourfold up-regulation on synovial fluid PMN compared with peripheral blood PMN (PBG) of the same patients; CD59 was increased twofold, the expression of CD16 did not change, whereas CD62L was reduced by more than 50% on synovial fluid PMN. It is interesting that CD66a, CD66b, and CD66c showed a coordinated expression on PBG of patients and controls and a coordinated up-regulation on synovial neutrophils. In contrast, after in vitro stimulation of peripheral blood PMN with phorbol myristate acetate, CD66c was much less up-regulated compared with CD66a and CD66b. All samples of synovial fluid PMN exhibited an additional increase in the expression of CD66a, CD66b, and CD66c when stimulated with phorbol myristate acetate in vitro. Prostaglandins are known to inhibit various responses of neutrophils to inflammatory stimuli. We could show that prostaglandins inhibit N-formyl-methionyl-leucyl-phenylalanine-induced up-regulation of CD66 on peripheral blood PMN in a concentration-dependent manner.

Adult↗

Thrombomodulin in systemic lupus erythematosus: association with clinical and laboratory parameters.

Thrombomodulin is an endothelial cell membrane glycoprotein and is detected in plasma and serum after endothelial injury. In our study comprising 311 patients with systemic lupus erythematosus (SLE) clinical and laboratory associations of elevated thrombomodulin serum concentrations were examined. Elevated thrombomodulin concentrations were detected in 7.1% of the SLE patients and were associated with nephritis including the laboratory parameters proteinuria and erythrocyte casts, vasculitis and neurological involvement of the central nervous system. These correlations remained significant after consideration of the influence of renal function. In SLE, the serum thrombomodulin concentration may become a marker to monitor damage of endothelial cells and involvement of the central nervous system.

Enzyme-Linked Immunosorbent Assay↗

Methotrexate-induced papular eruption in patients with rheumatic diseases: a distinctive adverse cutaneous reaction produced by methotrexate in patients with collagen vascular diseases.

BACKGROUND: In the past few years, low doses of methotrexate have been used for treatment of patients with rheumatoid arthritis and other collagen vascular diseases, mainly as an immunosuppressive and corticosteroid-sparing drug. Several cutaneous adverse reactions have been described in association with methotrexate therapy. OBJECTIVE: We describe the clinical and the histopathologic features of distinctive cutaneous lesions that appeared in 4 patients with acute bouts of collagen vascular diseases who were receiving methotrexate therapy. METHODS: We clinically and histopathologically evaluated cutaneous lesions caused by methotrexate therapy in 4 patients, 2 with systemic lupus erythematosus, 1 with rheumatoid arthritis, and 1 with Sharp syndrome. RESULTS: Clinically, lesions consisted of erythematous indurated papules most commonly located on proximal areas of the extremities. Histopathologic examination of these papules showed an inflammatory infiltrate mainly composed of histiocytes interstitially arranged between collagen bundles of the dermis, intermingled with few neutrophils. In some foci of deeper reticular dermis, small rosettes composed of clusters of histiocytes surrounding a thick central collagen bundle were seen. Cutaneous lesions showed a direct chronologic relationship with methotrexate therapy, and they disappeared when the drug was tapered or withdrawn and corticosteroids were increased. CONCLUSION: Patients receiving low doses of methotrexate for acute bouts of collagen vascular diseases may experience characteristic cutaneous lesions with distinctive clinical and histopathologic findings shortly after methotrexate administration. We discuss the differential diagnosis with other dermatoses showing similar histopathologic findings that have been described in patients with collagen vascular diseases.

Adult↗

Autologous haematopoietic stem cell transplants for autoimmune disease--feasibility and transplant-related mortality. Autoimmune Disease and Lymphoma Working Parties of the European Group for Blood and Marrow Transplantation, the European League Against Rheumatism and the International Stem Cell Project for Autoimmune Disease.

This ongoing multicentre prospective phase I/II trial enrolled 74 consecutive patients from 22 centres worldwide with severe autoimmune disease, 35 with rheumatological disorders, 31 with neurological, five with haematological and three with vasculitides. They were treated with autologous peripheral blood or bone marrow transplants according to predetermined criteria. Two patients died after mobilisation before transplant. Seventy-two patients were given 73 transplants, seven bone marrow, and 66 mobilised peripheral blood stem cell transplants. The graft was manipulated to remove T and/or B cells in 43 cases. All 73 transplants engrafted. Five patients died of transplant-related complications: two from bleeding, three from infections. Two patients died of progressive disease. The transplant-related mortality at 1 year of 9% (1-17%; 95% CI) is comparable to the transplant-related mortality of 6% (3-9%; 95% CI) in patients transplanted during the same period in Europe for non-Hodgkin's lymphoma in sensitive relapse (P = 0.39). Sixty patients are evaluable for response, 40 patients (65%) showed some improvement in their disease. Haematopoietic stem cell transplants are feasible for patients with severe refractory autoimmune disease. Transplant-related mortality is comparable to results in patients with non-Hodgkin's lymphoma in responsive relapse. Two-thirds of the patients show at least some response. These preliminary data are promising. Although associated with considerable risk, randomised trials comparing autologous stem cell transplants to conventional therapy are warranted.

Adolescent↗

Serum response elements activate and cAMP responsive elements inhibit expression of transcription factor Egr-1 in synovial fibroblasts of rheumatoid arthritis patients.

Analyzing the induction kinetics and promoter elements regulating the expression of the transcription factor Egr-1, we found elevated levels of Egr-1-encoding mRNA in synovial fibroblasts of rheumatoid arthritis (RA) patients when compared to controls. By contrast, synovial lymphocytes and macrophages do not show an elevated Egr-1 transcription. Therefore, the overexpression of Egr-1 may serve as a diagnostic marker to characterize synovial fibroblasts of RA patients. To study the regulatory mechanisms controlling Egr-1 expression we analyzed the function of transcription factor binding sites located in the Egr-1 promoter. Individual transcription factor binding sites within the Egr-1 promoter were specifically mutated and Egr-1 promoter activity was tested using reporter gene constructs. Our experiments demonstrate that serum response elements are the main positive regulators and binding to a cAMP responsive element represents the major negative regulator for Egr-1 expression in synovial fibroblasts. In addition, we functionally defined a new element, which was not yet described in the human Egr-1 promoter and which serves as a second negative regulatory element for Egr-1 expression. Therefore increased serum response factor activity or failure of Egr-1 repressing signals may account for Egr-1 overexpression in RA synovial fibroblasts.

Arthritis, Rheumatoid↗

Autoreactive human T cell lines recognizing ribosomal protein L7.

Sera of patients suffering from systemic lupus erythematosus (SLE) frequently contain oligoclonal IgG autoantibodies with high affinity for the ribosomal protein L7 (rpL7). The humoral autoimmune response to rpL7 apparently is driven by antigen and T cell dependent. In order to analyze the T cell response to rpL7 we cultured peripheral blood lymphocytes of healthy individuals and SLE patients in the presence of recombinant rpL7. After 10 days, the cytokine response to re-stimulation with rpL7 was examined using a spot-ELISA. Measuring IFN-gamma secretion, the T cells of two patients and four healthy donors showed a significant increase in the number of spots as compared to control cells. Secretion of IL-4 or IL-10 was not detected. From the antigen-stimulated primary cultures we established by limiting dilution cloning six rpL7-reactive, IFN-gamma-secreting T cell lines which show a CD3+CD4+CD8- phenotype. One line additionally was shown to be positive for HLA-DR and CD45R0, but negative for CD27 and CD31. The cell lines carry alphabeta TCR chains which differ from each other in sequence and specificity. rpL7 fragments rich in basic amino acids could be identified as epitopes recognized by the TCR of three cell lines. Recognition of rpL7 is HLA-DR6 restricted or respectively HLA-DP restricted in the two cell lines analyzed.

Amino Acid Sequence↗