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PubMed1982

Serologic and HLA associations in subacute cutaneous lupus erythematosus, a clinical subset of lupus erythematosus.

We studied the autoimmune serologic features and histocompatibility antigen associations of 27 patients who had a widespread, nonscarring and often photosensitive form of histologically specific cutaneous lupus erythematosus. We designated this disorder as subacute cutaneous lupus erythematosus. Skin lesions from this disorder can be distinguished from scarring discoid lupus erythematosus lesions both on a morphologic and histopathologic basis. Antinuclear and anticytoplasmic antibodies (Ro or Ro and La) and circulating immune complexes were frequently present in patients with subacute cutaneous lupus erythematosus, whereas rheumatoid factor and anti-lymphocyte, anti-DNA, anti-nRNP, and anti-Sm antibodies were found less frequently. Patients having annular skin lesions represented a particularly homogeneous subgroup in which there was a striking concordance of anti-Ro antibodies and the HLA-DR3 phenotype. These studies clearly establish that the presence of these lesions can serve as a cutaneous marker for a distinct subset of patients with lupus erythematosus who share similar clinical, serologic, and genetic features.

Adult↗
PubMed1999

Human brain pericytes as a model system to study the pathogenesis of cerebrovascular amyloidosis in Alzheimer's disease.

Cerebrovascular amyloidosis belongs to the pathological hallmarks of Alzheimer's disease brains. Although definite proof is still lacking, it is very well possible that the amyloid and its associated proteins are produced locally in the brain. In this paper we describe the development of a model system of cultured human brain pericytes to study the mechanisms of microvascular amyloid formation in vitro. These cultured cells may serve to study several aspects of cerebrovascular amyloidosis, which include the production of the amyloid precursor protein and of amyloid beta-protein-associated proteins as well as cytotoxic effects of amyloid beta-protein on perivascular cells. We demonstrated that pericytes produce and metabolize the amyloid precursor protein, and that they produce amyloid beta-protein-associated proteins, such as heparan sulfate proteoglycans, apolipoprotein E, and complement factor C1q. They are also prone to cellular degeneration after treatment with amyloid beta-protein, which is accompanied by increased expression of a number of amyloid beta-protein-associated proteins. This may be an important mechanism to explain the cell death observed in vivo. Our data indicate that this cell culture model of human brain pericytes provides a useful and pathophysiologically relevant tool to study cerebrovascular amyloidosis.

Alzheimer Disease↗
PubMedDate not supplied

Clinicopathological conference: an 11-year-old boy with recurrent infections, hypertension, skin rash, and nephritic syndrome.

In this clinicopathological conference, an 11-year old boy who presented with recurrent pyogenic infections, hypertension, malar rash, various skin lesions and nephritic syndrome since five years of age is discussed. He was hospitalized for clinical investigation with skin and renal biopsies at 10 years of age. Using clinicopathological data obtained from his last admission, a clinical diagnosis was reached, and the disorders of the complement system causing patients to show these signs or symptoms are emphasized. At the end of the discussion, a clinicopathological correlation is given for making the diagnosis.

Child↗
PubMed2003

[Recently discovered hormones with a role in energy homeostasis].

Adipocytal hormones resistin and adiponectin and gastric peptide ghrelin are recently discovered hormones, which are considered to take part in energy metabolism regulation. Resistin is expressed in adipose tissue only and its increased levels could cause insulin resistance and thus link obesity with type 2 diabetes. Adiponectin, as well as resistin, are products of genes, expressed in adipose tissue. Adiponectin could prevent development of aterosclerosis and it could play a role in anti-inflammatory reactions. Ghrelin is produced mainly in the stomach. Beside its role in long-term regulation of energy metabolism, it is involved in the short-term regulation of feeding. Main roles of resistin, adiponectin and ghrelin are summarised in the presented overview.

Adiponectin↗
PubMed1992

[Renal lesions of post-hepatitis cirrhosis].

There have been many reports on renal lesions of alcoholic cirrhosis, but not on those of post-hepatitis cirrhosis (PHC) up to present. A clinical and pathological observation on PHC was carried out prospectively in 18 and retrospectively in 34 cases. Renal specimens were examined with light and electron microscopy and immunopathological methods (immunofluorescence and peroxidase anti-peroxidase). Clinically, recurrent gross hematuria was observed in 2 and wild urinary abnormality in 17 cases. One case developed renal failure and the remaining 32 cases had no clinical evidence of renal involvement. Light microscopy showed wild mesangial lesions in 44 cases and glomerular basement membrane (GBM) thickening with segmental splitting in 29 and diffuse splitting in 2 cases. Massive protein deposition was found in the GBM, mesangium (Ms) and tubular basement membrane as well as the epithelium and endothelium. Immunopathological examination showed massive deposition of various immunoglobulins and complements in GBM and Ms, with IgG dominant in 8, IgM dominant in 7, IgA dominant in 6 and "full house" in 11 cases. HBsAg was detectable in GBM and Ms in 5 cases (9.6%) and HBcAg in one. Focal interstitial fibrosis and lymphocytic infiltration were found in 15 (28.3%). Our data revealed that renal lesions of post-hepatitis cirrhosis are different from those of the so-called "cirrhotic glomerulonephritis" in certain aspects. They are characterized by definite GBM involvement and massive deposition of immunoglobulins and complements. Its pathogenesis may be more complicated than that of other types of liver cirrhosis.

Adolescent↗
PubMedDate not supplied

Anti-Clq antibodies in patients with chronic hepatitis C infection.

OBJECTIVE: Extrahepatic autoimmune features of HCV infection include autoantibody production and the development of mixed cryoglobulinemia. Anti-Clq antibody, detected with high frequency in systemic lupus erythematosus and hypocomplementemic urticarial vasculitis, may have a direct pathogenic role in complement mediated autoimmune diseases. In this study, we investigate the prevalence of anti-Clq antibody in a population of patients with chronic HCV infection. METHODS: Serum was obtained from a group of 50 patients with chronic HCV infection and control groups comprised of patients with SLE, rheumatoid arthritis (RA), scleroderma (PSS), Sjögren's syndrome (SS), mixed connective tissue disease (MCTD), and healthy individuals. RESULTS: Anti-Clq antibody was detected in 38% of HCV patients compared with 2% of healthy controls (p < 0.0001). Levels were also significantly elevated in patients with SLE (61%), RA (20%), PSS (15%), SS (15%) and MCTD (15%). CONCLUSION: In addition to numerous other autoantibodies, patients with chronic HCV infection exhibit increased production of anti-Clq IgG antibodies. This observation may have implications for the pathogenesis of the mixed cryoglobulinemic vasculitis syndrome.

Arthritis, Rheumatoid↗
PubMed1991

[Elevated Clq-bearing immune complexes in hemophiliacs with viral infections].

One hundred hemophilia A and 30 hemophilia B patients who had been treated with non-heated and heated factor VIII or prothrombin complex concentrates were examined by immunological tests including Clq-bearing immune complexes assay. Antibodies to human immunodeficiency virus type 1 (HIV-1), hepatitis B virus (HBV), hepatitis C virus (HCV) and human parvovirus B19 (B19) were analyzed by Western blotting, enzyme immunoassay, passive hemagglutination or radio-immunoassay. Clq-bearing immune complexes were assayed by a monoclonal anti-Clq ELISA system (Immunomedics). Seropositivity to HIV-1, HBV, HCV, and B19 was 56.9%, 87.7%, 79.2% and 100% respectively. Clq-bearing immune complexes were positive in 109 of the 130 patients (83.8%). The positivity and the levels were extremely higher than those in normal individuals. Clq-bearing immune complex levels in patient positive for HIV-1, HCV, or HBV were higher than those in the negative group (HIV: P less than 0.001, HCV: P less than 0.005, HBV: P less than 0.05). When the patients were divided into four groups according to seropositivity to HIV-1 and/or HCV, Clq-bearing immune complex levels were the highest in the group positive for both antibodies, and the lowest in the group negative for both antibodies. These results suggested that each viral infection influences the formation of immune complexes and repeated viral infection increased the level of Clq-bearing immune complexes in these patients.

Adolescent↗
PubMed1991

Effect of early synovectomy on the course of rheumatoid arthritis.

Ninety-one patients with rheumatoid arthritis were retrospectively assigned to 3 subsets according to the number of joints with erosion (NJE). The subsets were least erosive (LES); more erosive (MES); most erosive involving multilating disease (MUD). In the early stages of disease the subsets were distinct (p less than 0.001) regarding mean values of annual reduction of carpal height (delta CHR) and serum Clq levels. Patient assessment (radiographic and clinical) continued to deteriorate in the MES and MUD subsets over the 1-5 year interval after synovectomy. Apparent stabilization of knee disease in the LES subset may be a feature of this subset rather than a result of synovectomy. Although synovectomy may offer short term symptomatic relief, we found no evidence that it retards the bony destruction or the disease process.

Adult↗
PubMed1991

[Cryoglobulinemia and fibronectin in systemic lupus erythematosus].

EIA was used to measure the concentration of fibronectin in plasma and cryoprecipitates of 37 patients suffering from systemic lupus erythematosus coupled with cryoglobulinemia. A definite relationship was discovered between the level of cryoglobulins and the activity of SLE, the concentration of fibronectin in plasma and liver damage. A tendency was revealed towards increase of the fibronectin content in plasma of patients with a high level of antibodies to native DNA and CIC as was a significant correlation between the concentration of cryoglobulin protein and the concentration of fibronectin in cryoprecipitates.

Adolescent↗
PubMed1990

Changes in peripheral blood lymphocytes and immune complexes in splenectomized patients: lack of correlation with residual splenic function.

In 47 patients who had undergone splenectomy (31 post-trauma and 16 elective), the percentage levels of T and B lymphocytes, and the T lymphocyte subsets and circulating immune complexes were studied in peripheral blood and correlated with residual splenic function evaluated by means of the pitted red cell count. The T and B lymphocyte levels in splenectomized patients did not differ significantly from those in controls, while OKT8+ lymphocyte levels were significantly higher both after post-trauma and elective splenectomy; there was no significant difference between the two groups of splenectomized patients. Circulating immune complexes were significantly higher both after post-trauma and elective splenectomy only with the C1qBA and C1qSP methods, while there were no differences between splenectomized patients and controls with the KgBSP method. None of the three methods showed significant differences between post-trauma and electively splenectomized individuals. The pitted red cell levels were significantly lower in post-trauma splenectomized patients with respect to electively splenectomized individuals and 22% of post-trauma splenectomized patients had pitted red cell values within the range compatible with the presence of splenosis. The immunological alterations detected did not correlate with the pitted red cell levels, nor were they less evident after post-trauma splenectomy or in patients with pitted red cells compatible with splenosis: this suggests that the occurrence of splenosis is not sufficient to prevent these alterations. Finally, since in our study the average distance from the operation was 5 yr, it is likely that these alterations can be considered as being stable.

Adult↗
PubMed1991

Primary structure of bovine conglutinin, a member of the C-type animal lectin family.

We report the complete amino acid sequence of bovine conglutinin obtained by structural characterization of peptides derived from the protein by various chemical and enzymatic fragmentation methods. The protein consists of 351 amino acid residues including 55 apparent Gly-X-Y repeats with two interruptions. This 171-residue-long collagenous domain separates a short noncollagenous NH2-terminal region of 25 residues from the 155-residue-long globular COOH terminus revealing the structural relation of conglutinin with mannose-binding proteins, pulmonary surfactant-associated proteins, and a complement component C1q. Eight hydroxylysine residues were found in the collagenous domain. All of these hydroxylysine residues which occupy a Y position in a Gly-X-Y triplet are possible glycosylation sites since no phenylthiohydantoin amino acid was identified in automated Edman degradation cycles corresponding to these sites. The noncollagenous COOH domain of conglutinin, on the other hand, contains a carbohydrate recognition domain which shares substantial sequence homology with C-type animal lectins. Conglutinin has the greatest sequence similarity with mannose-binding proteins and pulmonary surfactant-associated proteins.

Amino Acid Sequence↗
PubMed1990

[The immunomodulating properties of a macro glycopeptide isolated from serum. II. The activation of macrophages and polymorphonuclear cells].

The stimulating properties of three fractions of a glucomacropeptide consisting of different carbohydrate and peptide components were studied. The phagocytic activity of polymorphonuclears was increased on the 24th hour and of macrophages on the 3rd day after application of the preparations to mice. In vitro fraction 3 stimulates the lysozyme activity and the synthesis of proteins and Clq of the macrophages complement. These properties of the cells are collaborated by the established ultrastructural changes. The different composition of the fractions determines their immunostimulating effect.

Adjuvants, Immunologic↗
PubMed1990

IgA nephropathy in Pakistan.

A light, electron and immunofluorescence microscopy study was performed on 102 consecutive patients on whom suitable percutaneous renal biopsies were obtained. In this selected group of patients primary IgA glomerulonephritis was diagnosed in 6 (5.9%) cases. On light microscopy the glomerular lesions were predominantly focal (WHO class III) and diffuse mesangial proliferative glomerulonephritis (Class IV). The mesangial deposits showed high association with IgM deposits and presence of early complement components (C1q, C4) indicative of both classical and alternative pathways of C3 activation in our patients. The high incidence of nephrotic syndrome with microhaematuria (5 cases) is due to patient selection when compared to other studies. This study shows the existence of IgA nephropathy in Pakistan and larger number of cases need to be investigated to determine the true prevalence of this disease and its clinical manifestations and importance in Pakistan.

Adolescent↗