Biomedical subjects

M Agusti

Publications and source records attributed to M Agusti.

7 recordsLinked to original sources

PubMed1994

Autoantibodies against a novel DNA-binding protein: DNA-protein interaction as a requisite for expression of antigenic reactivity.

A novel DNA-binding protein complex, the HB complex, has been characterized by means of autoantibodies. Three proteins of 9000, 7500, and 7000 Da constitute the HB complex. The 9000- and 7500-Da proteins are phosphorylated. Autoantibodies recognize the 7000-Da protein when it is bound to DNA. No reactivity against any protein was observed when the complex was dissociated from DNA. The three proteins are acidic (pI 5-6.2), and the complex was able to bind to synthetic double-stranded DNAs of different composition.

Animals↗

PubMed1991

Effect of intraventricular injection of an anti-Purkinje cell antibody (anti-Yo) in a guinea pig model.

Female guinea pigs had intraventricular injections of either IgG from a patient with paraneoplastic cerebellar degeneration (PCD) and anti-Purkinje cell antibodies (anti-Yo IgG) or control IgG. In animals that received a single injection of control or anti-Yo IgG and were killed at different time intervals, IgG immunoreactivity was present in the cytoplasm of Purkinje cells at 2 h and persisted at 24 h. In guinea pigs injected for 15 days with control or anti-Yo IgG and sacrificed 24 h after the last injection, IgG was detected into the Purkinje cells in both groups, whereas animals killed 7 and 30 days after the last injection had no staining for IgG in the Purkinje cells. Clinical or pathologic evidence of cerebellar involvement was not seen in any of the animals. This study suggests that anti-Yo antibody alone may not be the cause of the Purkinje cell loss in PCD.

Animals↗

PubMed1988

Characterization of the CB antigen, a DNA-binding protein recognized by autoantibodies and which has a differential expression in lymphoid cells.

We have analyzed the characteristics of the CB Ag, a nuclear protein recognized by autoantibodies. Approximately 4% (12 out of 280) of the antinuclear-positive sera examined contained anti-CB antibodies. By immunofluorescence, these sera brightly stained the nuclei of most cells analyzed, including peripheral lymphocytes, but only dull or no staining was observed in thymocytes or B cells of the bursa of Fabricius. The CB Ag has been characterized as a DNA-binding protein, dissociable from DNA at 1.5 M NaCl, and with a Mr of 40,000 Da. Moreover, the ability of the extracted Ag to bind back to DNA has enabled us to design an ELISA system for its detection.

Adult↗

PubMed1988

Characterization of the antigen reactive with anti-Scl-70 antibodies and its application in an enzyme-linked immunosorbent assay.

The characteristics of the Scl-70 antigen (topoisomerase I) have been analyzed by means of autoantibodies. This antigen is a DNA-binding protein, dissociable from DNA at 0.3M NaCl and bound to a fraction of DNA that is very sensitive to nucleases. The molecular weight of the antigen is 105,000 daltons, whether dissociation conditions are used or not. Using chicken erythrocytes, and taking advantage of the strong interaction of the antigen with hydroxyapatite, we have designed a simple and fast purification protocol that allows the determination of anti-topoisomerase I antibodies by enzyme-linked immunosorbent assay.

Antibodies, Antinuclear↗

PubMed1987

Autoantibodies against the H1(0) subtype of histone H1.

The specificity of antinuclear autoantibodies in a patient with a sensory neuropathy associated with cancer has been analyzed. The autoantibodies recognize the histone H1(0) as shown by its dissociation from DNA, perchloric solubility, electrophoretic mobility in SDS or urea/acid polyacrylamide gels, and by the capacity of purified H1(0) to block the reactivity of these autoantibodies. Almost no reactivity was observed with other subtypes of H1. To our knowledge, this is the first autoantibody described with such specific reactivity for the H1(0) subtype.

Aged↗

PubMed1987

Effect of enzymatic treatments on RNP and Sm antigenic reactivities--I. Loss of RNP but increase of Sm antigenic reactivity after RNase treatment of nuclear extract.

Changes of RNP and Sm antigenic reactivities of a nuclear extract after enzymatic treatments were studied and quantified by the ELISA test. After RNase treatment of the nuclear extract, about a 300% increase of the Sm antigenic reactivity and more than a 95% decrease of RNP antigenic reactivity was found. Data from RNP-depleted nuclear extracts and column fractionation show that the increase in Sm antigenic reactivity after RNase treatment mainly comes from the RNP-Sm complex.

Antibodies, Antinuclear↗

PubMed1987

[Isolated macronodular sarcoidosis].

A particular case of macronodular isolated sarcoidosis with neurological and ocular involvement is presented, associated with pseudo-balding. A revision of the most important aspects of the diagnostic of this multifaceted disease is realized. The benefits of a surgical treatment for the cases of isolated nodes are pointed out.

Abscess↗