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Biomedical subjects

N Abuaf

Publications and source records attributed to N Abuaf.

87 records · Page 5Linked to original sources
PubMedDate not supplied

Chronic active hepatitis associated with antiliver/kidney microsome antibody type 1: a second type of "autoimmune" hepatitis.

Sixty-five patients with histologically proven chronic active hepatitis of unknown cause but associated with the antiliver/kidney microsome antibody type 1, confirmed by immunofluorescence and immunoprecipitation, were selected as forming a special entity. This disease was found to be rare with a prevalence of 5/1,000,000. The female to male ratio was 8:1. The condition occurred at all ages but was most common between the ages of 2 and 14 years. In 22 of the 65 cases, the hepatitis was associated with an autoimmune disease, most commonly insulin-dependent diabetes, autoimmune thyroid disease and vitiligo. The same autoimmune diseases were present in first-degree relatives from seven families. In 36 cases, the onset of disease resembled acute viral hepatitis. Serum biochemical tests showed marked elevation in aminotransaminases and hypergammaglobulinemia. Paradoxically, serum and salivary IgA levels were often normal or low. Histologic findings were multifocal hepatic necrosis with bridging in the acute stage, and aggressive hepatitis with mononuclear cell infiltration or macronodular cirrhosis in the late stages. Serologically, apart from the presence of antiliver/kidney microsome antibody type 1, the disease was characterized by the absence of antiactin, antimitochondria and antinucleus antibodies; however, organ-specific autoantibodies were often present. The clinical course was usually severe: six patients in the acute stage presented with fulminant hepatitis, and all, except two, other patients progressed to cirrhosis. Prolonged treatment with corticosteroids and immunosuppressants was usually effective in rendering the cirrhosis inactive. The cumulative survival rate was 51% at 14 years. We propose to call this entity "anti-LKM1 chronic active hepatitis" or "autoimmune hepatitis type II" to differentiate it from classical "lupoid hepatitis" or autoimmune hepatitis type I.

Autoantibodies↗
PubMedDate not supplied

Antibody to liver cytosol (anti-LC1) in patients with autoimmune chronic active hepatitis type 2.

A new autoantibody was detected by immunoprecipitation in the serum of 21 patients with chronic active hepatitis. The antibody reacted against a soluble cytosolic antigen in liver. The antibody was organ specific but not species specific and was therefore called anti-liver cytosol antibody Type 1 (anti-LC1). In seven of 21 cases, no other autoantibody was found; the remaining 14 cases had anti-liver/kidney microsome antibody Type 1 (anti-LKM1). With indirect immunofluorescence, a distinctive staining pattern was observed with the seven sera with anti-LC1 and without anti-LKM1. The antibody stained the cytoplasm of hepatocytes from four different animal species and spared the cellular layer around the central veins of mouse and rat liver that we have called juxtavenous hepatocytes. The immunofluorescence pattern disappeared after absorption of sera by a liver cytosol fraction. The 14 sera with both antibodies displayed anti-LC1 immunofluorescent pattern after absorption of anti-LKM1 by the liver microsomal fraction. The anti-LC1 was found in the serum only in patients with chronic active hepatitis of unknown cause. Anti-LC1 antibody was not found in sera from 100 patients with chronic active hepatitis associated with anti-actin antibody classic chronic active hepatitis Type 1, 100 patients with primary biliary cirrhosis, 157 patients with drug-induced hepatitis and a large number of patients with liver and nonliver diseases. This new antibody was considered a second marker of chronic active hepatitis associated with anti-LKM1 (anti-LKM1 chronic active hepatitis) or autoimmune chronic active hepatitis Type 2.

Antibodies↗
PubMedDate not supplied

[The diagnostic value of anti-DNA antibodies depends on the technic used for their detection].

Three anti-native DNA antibody detecting assays were compared using sera from 948 patients with clinical symptoms of connective tissue disease and 55 definite systemic lupus erythematosus patients. The Farr assay was more effective than the two other assays in the diagnosis of lupus. Anti-DNA antibody detection by ELISA was as sensitive as the Farr assay; in contrast indirect immunofluorescence on Crithidia luciliae had a significantly lower sensitivity, detecting less than one out of two cases of lupus detected. Particularly ELISA but also indirect immunofluorescence may give positive results in the absence of lupus, so that results obtained by each of these assays must be confirmed by the Farr assay if they are used in the diagnosis of lupus. The significance of antibodies detected by one assay but not by the others is discussed.

Antibodies, Antinuclear↗
PubMedDate not supplied

[Eosinophilia and respiratory function in the asthmatic (author's transl)].

Total eosinophil count (TEC) was done in 13 normal subjects, in 8 subjects before and 90 mn after a "French" breakfast and in 29 asthmatic patients. The geometric mean is higher (p less than 0,001) in asthmatic than in normal subjects: 304 (231--391) versus 144 (101--197). The breakfast does not interfer with the result of the TEC. In asthmatic subjects, a significant inverse correlation appears (r = 0,57, p less than 0,01) between the logarithm of TEC and the quotient: formula; see text. This correlation persists whatever may be the subject's age, the duration of the asthma or age at which he first contracted the illness. Asthma appeared after 40 years in 4 of the subjects: their TEC was higher (p less than 0,01) than in subjects who had become asthmatic before the age of forty. The respiratory function was lowered more in these 4 patients than in others who had been ill for the same time (p less than 0,001). The TEC is not related to results of skin testine with usuel inhalant allergens (grass pollen, house dust, cat's or dog's dander) or by result of a provocation test (by inhalation of allergen). Eosinophilia and bronchial obstruction are connected by one (or more) factors that may be inhalant allergens in extrinsec asthma and circulating immune complexes in intrinsec asthma.

Adolescent↗
PubMedDate not supplied

[Antinuclear antibodies in primary biliary cirrhosis].

Antinuclear and antinuclear membrane autoantibodies are detected by indirect immunofluorescence in sera of 62 p. 100 of primary biliary cirrhosis patients; when anti-SS-A (Ro) and anti-SS-B (La) autoantibodies were included, 70 percent of patients had at least one type of antinuclear antibody. Of 89 patients with primary biliary cirrhosis, 30 had either Raynaud's phenomenon, Sjögren's syndrome or the CREST syndrome. Some antinuclear antibodies, anticentromere and speckled S1 type, seem to correlate with the associated connective tissue disease. Antibodies showing the S3 pattern (multiple nuclear dots) and antibodies to nuclear membrane may be present independently of an association with connective tissue disease. In the classical technical conditions used to detect anti-tissue and anti-mitochondrial autoantibodies on tissue sections, antinuclear antibodies like anti-centromere or S3 may not be detected and/or identified. Primary biliary cirrhosis patient sera for antinuclear antibodies determination must be screened by at least two assays: indirect immunofluorescence on a human cell line, like HEp-2, and immunodiffusion. The last assay must be performed even if antinuclear antibodies are undetected by immunofluorescence.

Antibodies, Antinuclear↗
PubMedDate not supplied

[Anti-centromere antibody, biological marker of the CREST syndrome as distinct from scleroderma].

Using HEp2 cells to study antinuclear antibodies has resulted in the discovery of the anti-centromere antibody which is thought to separate the CREST syndrome from progressive systemic sclerosis (scleroderma). This antibody seems to be exceptional in healthy subjects and are in patients with connective tissue diseases, except for scleroderma. It has also been found in CREST syndrome associated with other diseases, such as primary cirrhosis and neoplasias. In our study, the sensitivity of the anti-centromere antibody was 89.1% and its specificity 92.3% which shows that it is worth looking for.

Adult↗
PubMedDate not supplied

[Cellular interaction in the pokeweed-mitogen induced terminal differentiation to polyclonal immunoglobulin production in human B lymphocytes in vitro].

The differentiation of human B lymphocytes in vitro into Ig secreting cells, as measured by a radioimmunoassay rendered specific to IgG and IgM, in response to a polyclonal stimulant, requires the participation of several cellular types. Upon poleweed-mitogen stimulation, B-cell enriched and monocyte containing cell suspensions prepared by elution of nylon wool adherent cells, when mixed with various concentrations of T cells purified by filtration through nylon wool column and depletion of EAC-rosette forming cells, synthesize 5 to 20 times more Ig than non separated lymphocytes. These experiments which demonstrate the cooperation of certain T cells also suggest that other cells eliminated by nylon wool adherence act as suppressor cells. The cooperation of these T cells is independent of their proliferation and can be obtained with allogeneic T cell.

B-Lymphocytes↗
PubMedDate not supplied

[Functional studies of T and B lymphocytes].

The means for analysing T-cell activities are very limited. Indeed, the numerical estimation of the changes which take place in human T lymphocytes had to rely solely on the observation of transformed cells (blasts). However, even if various mitogens appear selective for either T of B cells, we know that both types of lymphocytes are ultimately transformed into blasts. This is particularly true in studies conducted on mixtures of T and B cells where stimulated T cells can release substances which act on B cells. On the other hand, studies with purified populations of T or B cells do not express the cellular interactions that occur naturally between these two types of lymphocytes. For all these reasons, it seemed that the estimation of " quanta " of activity unique to T lymphocytes would contribute significantly to our knowledge of this line of cells. We describe a new method of detecting the in vitro stimulation of lymphocytes based on the appearance of cells having the property to cluster several layers of sheep red blood cells (SRBC) around themselves, forming multilayer rosettes (CFC). This formation is temperature-dependent and requires trypanblue-excluding, metabolically active blastoid cells. Non-separated cells as well as purified T cells stimulated with allogeneic leucocytes (MLR), specific antigens or polyclonal mitogens (PWM, ConA) gave rise to CFC. Such multilayer rosettes were not formed by separated B cells. In the MLR, CFC were detected 48 h after beginning of cultures and increased in number thereafter just like thymidine incorporation. The response to ConA and PWM was detected earlier and gave rise to two or three peaks, the first rise in the number of CFC coinciding with the peak of thymidine incorporation, but the maximal increase occurring two or three days later. Treatment of blastoid cells with a serum specific for T cells--but not with an anti-immunoglobulin serum--abolished their ability to form ordinary or multilayer rosettes. When separated, however, on a nylon wool column, CFC were more adherent than the bulk of T cells. It is suggested that CFC form a subpopulation of T cells with distinct characteristics, allowing a direct assessment of membrane changes which take place when T lymphocytes are activated in vitro.

B-Lymphocytes↗
PubMedDate not supplied

Autoantibody formation in D-penicillamine-treated rheumatoid arthritis.

One hundred and two rheumatoid arthritis patients were tested before treatment for the presence of 16 autoantibodies. Low titers of antinuclear factors appeared, but there were no antitissue antibodies. At different intervals during the treatment of a 2nd series of 176 patients, elevations of antinuclear factors were observed that correlated slightly with either autoimmune or toxic side effects. Antitissue antibodies were seen only in pemphigus and myasthenia after the onset of these complications. The practical value of systematic evaluation for autoantibodies in penicillamine-treated rheumatoid patients is questionable.

Adult↗