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F Gaskin

Publications and source records attributed to F Gaskin.

At least 19 recordsLinked to original sources
PubMed2003

Autoantibodies and glomerulonephritis in systemic lupus erythematosus.

Autoantibody diversification to a variety of autoantigens is a hallmark for systemic autoimmunity. SLE represents a prototype. In this article the roots of the important questions probed by the Kunkel laboratory in SLE research are traced. Data from the recent animal work by the laboratory of Shu Man Fu are summarized to emphasize the importance of further exploration of autoantibody specificities in lupus with a special emphasis on nephritis and to suggest a broader perspective regarding lupus autoantibody reactivities in addition to those against nuclear components.

Animals↗
PubMed2001

NZM2328: a new mouse model of systemic lupus erythematosus with unique genetic susceptibility loci.

Among NZB/W-derived New Zealand mixed (NZM) strains, only NZM/Aeg2410 (NZM2410) has been well characterized. In contrast to NZM2410, NZM2328 mice develop autoantibodies and acute and severe chronic glomerulonephritis (GN) with female predominance similarly to NZB/WF1 and humans with systemic lupus erythematosus (SLE). Chronic GN with glomerular sclerosis and tubular atrophy but not acute GN was correlated with severe proteinuria. In a backcross analysis of (NZM2328 X C57L/J) F1 X NZM2328, four SLE susceptibility genomic intervals were identified. One of them (Cgnz1) is on the telomeric end of chromosome 1 and close to Sle1. It was significantly linked to chronic GN. A locus (Agnz1) distinct from Cgnz1 on this interval was suggestively linked to acute GN. Two genetic intervals on chromosome 17 were also suggestively linked to acute GN, one of which is the H-2-Tnf complex, while the other (Agnz2) is on the distal end of the chromosome. A single locus (Adaz1) identified in the midregion of chromosome 4 in NZM2328 mice was suggestively linked to plasma levels of IgG anti-dsDNA autoantibodies. These results differ significantly from those in the backcross analysis of (NZM2410 X C57BL/6)F1 X NZM2410 by other investigators. They support the concept that different sets of genes are involved in acute and chronic GN. The genomic differences between the NZM strains and between C57L/J and C57BL/6 account for the differences between our analysis and that on NZM 2410. These results provide evidence for the importance of background genes on the expression of SLE, with implications for genetic studies of human SLE.

Animals↗
PubMed2000

Ro60 peptides induce antibodies to similar epitopes shared among lupus-related autoantigens.

The coexistence of autoantibodies to ribonucleoproteins (RNP) in sera of patients with systemic lupus erythematosus has been attributed to intermolecular determinant spreading among physically associated proteins. Recently, we showed that murine Ab responses to rRo60 or Ro60 peptides were diversified unexpectedly to small nuclear RNP. In this investigation, the mechanisms for this autoantibody diversification were examined. Intramolecular determinant spreading was demonstrated in mice immunized with human or mouse Ro60316-335. Immune sera depleted of anti-peptide Ab immunoprecipitated Ro60-associated mY1 and mY3 RNA and remained reactive to a determinant on Ro60128-285. Absorption with the immunogen depleted the immune sera completely of anti-Golgi complex Ab (inducible only with human Ro60316-335) and anti-La Ab, and reduced substantially Ab to SmD and 70-kDa U1RNP. Mouse rRo60 completely inhibited the immune sera reactivity to La, SmD, and 70-kDa U1RNP. However, La, SmD, and 70-kDa U1RNP preferentially inhibited the antiserum reactivities to these Ags, respectively. Affinity-purified anti-La Ab were reactive with Ro60, La, SmD, and 70-kDa U1RNP. These results provide evidence that a population of the induced autoantibodies recognized determinants shared by these autoantigens. Lack of sequence homology between Ro60316-335 and La, SmD, or 70-kDa U1RNP suggests that these determinants are conformational. Interestingly, similar cross-reactive autoantibodies were found in NZB/NZW F1 sera. Thus, a single molecular mimic may generate Ab to multiple RNP Ags. Furthermore, cross-reactive determinants shared between antigenic systems that are not associated physically (Ro/La RNP and small nuclear RNP) may be important in the generation of autoantibody diversity in systemic lupus erythematosus.

Absorption↗
PubMed1999

Immune responses to Ro60 and its peptides in mice. I. The nature of the immunogen and endogenous autoantigen determine the specificities of the induced autoantibodies.

Anti-Ro60 autoantibodies are found in a variety of autoimmune disorders including systemic lupus erythematosus (SLE), Sjögren's syndrome, primary biliary cirrhosis, and active hepatitis. They are the most prevalent autoantibodies in normal individuals and in asymptomatic mothers of infants afflicted with neonatal lupus. In the present study, immune responses to recombinant human Ro60 (rhRo60) and recombinant mouse Ro60 (rmRo60) and selected Ro60 peptides in non-SLE-prone mice were investigated. Multiple T and B cell epitopes were identified in Ro60. Immunizations with either xenogeneic or autologous Ro60 induced autoantibodies to a diverse group of autoantigens. In addition to La and Ro52, proteins in the small nuclear ribonucleoprotein (snRNP) particles such as SmA, SmB, SmD, and 70-kD U1-RNP were unexpectedly identified as targeted antigens. In the studies involving synthetic Ro60 peptides, both human and mouse Ro60316-335 peptides, which differ in three amino acids, were found to contain dominant cross-reactive T cell determinants. Immunizations with these peptides induced autoantibodies to Ro60, La, SmD, and 70-kD U1-RNP without autoantibodies to Ro52, SmA, or SmB. With human Ro60316-335 as the immunogen, additional autoantibodies reactive with the Golgi complex were found. In contrast to the immunodominance of both human and mouse Ro60316-335 peptides, the T cell determinant in human Ro60441-465 was dominant, whereas that in the mouse peptide was cryptic. Immunization with human Ro60441-465 induced primarily anti-peptide Abs. Mouse Ro60441-465 failed to induce an antibody response. These results show that both the nature of the immunogen and the immunogenicity of the related endogenous antigen are important in determining the specificities of the autoantibodies generated. They have significant implications for proposed mechanisms on the generation of complex patterns of autoantibodies to a diverse group of autoantigens in SLE patients.

Animals↗
PubMed1998

Probing the ATP binding site of tubulin with thiotriphosphate analogues of ATP.

Tubulin assembly studies with GTP alpha S diastereoisomers have shown that there is stereoselectivity at the alpha-phosphate binding region of tubulin. GTP alpha S(Sp) bound tighter than GTP alpha S(Rp) and promoted nucleation and assembly better than GTP and GTP alpha S(Rp). ATP and dATP have been reported to bind weakly to tubulin and to be less effective than GTP and dGTP in promoting tubulin assembly. This study was done to learn if ATP alpha S(Sp) and dATP alpha S(Sp) are good promoters of tubulin assembly and to compare these ATP thiotriphosphate analogues to the corresponding GTP analogues in tubulin assembly. Studies were also done with ATP alpha S(Rp), GTP, ATP beta S(Sp) and ATP gamma S. At least three cycles of tubulin (25 microM) assembly-disassembly were found with 1 mM ATP alpha S(Sp) and dATP alpha S(Sp) and both nucleotides were incorporated and hydrolyzed in the polymers. Less dATP alpha S(Sp) (25 microM) than ATP alpha S(Sp) (100 microM) promoted assembly to 50% of the maximum value. The critical concentrations (Cc) for assembly with 1 mM nucleotide were low for ATP alpha S(Sp) (3 microM) and dATP alpha S(Sp) (2 microM) and compared favorably with GTP (5 microM), GTP alpha S(Sp) (2 microM) and dGTP alpha S(Sp) (1 microM). Both 1 mM ATP and dATP were poor promoters of tubulin assembly and were not detected in the polymers. The predominant structures induced by 1 mM (ATP alpha S(Sp) and dATP alpha S(Sp) were bundles of sheets and microtubules, which were more stable to the cold and to Ca(II) than microtubules assembled with GTP, ATP or dATP. ATP alpha S(Rp) (1 mM) did not promote assembly suggesting that there is stereoselectivity at the ATP alpha S alpha-phosphate binding region of tubulin as there is with GTP alpha S diastereoisomers. ATP alpha S(Sp) and dATP alpha S(Sp) mimic GTP alpha S(Sp) and dGTP alpha S(Sp) in tubulin assembly since all four nucleotides promote bundles of tubulin in buffer with glycerol, and the deoxy nucleotides have lower Cc, shorter lags and faster rates for tubulin assembly.

Adenosine Triphosphate↗
PubMed1997

Increased incidence of anti-beta-amyloid autoantibodies secreted by Epstein-Barr virus transformed B cell lines from patients with Alzheimer's disease.

During the past several years, evidence has been accumulated to support the thesis that immunological factors may play some role in Alzheimer's disease (AD). We have characterized the reactive antigens detected by certain monoclonal antibodies secreted by Epstein-Barr virus (EBV)-transformed B cell lines from the peripheral blood of AD patients and controls. Autoantibodies against beta-amyloid protein beta-amyloid protein (beta-A) in amyloid plaques and blood vessels and in enzyme-linked immunosorbent assays (ELISA) have been reported in four cell lines derived from an AD patient. In this study, over 3300 EBV-transformed B cell lines from thirteen individuals were tested in ELISAs for antibodies against beta-A peptides. Significantly more autoantibodies against beta-A (1-40) were found in the AD group, 2.26 +/- 0.62% (39/1794 cell lines) than in the control group, 0.28 +/- 0.36% (5/1552 cell lines) with P < 0.005. These new antibodies did not react with plaques or amyloid deposits in blood vessels. In contrast to the four plaque-reactive autoantibodies which reacted better with beta-A (1-40) than with beta-A (1-28), 70% of these anti-beta-A (1-40) antibodies reacted as well or better with beta-A (1-28). Many of them were also reactive with beta-A (1-16). Tested against a panel of cytoskeletal proteins and Hela cells, many of these anti-beta-A (1-40) antibodies appear to be polyreactive. The higher incidence of anti-beta-A antibody secreting B cells in AD patients provides further evidence that autoimmunity may play a role in AD.

Adult↗
PubMed1997

Bcl-2 and c-myc expression, cell cycle kinetics and apoptosis during the progression of chronic myelogenous leukemia from diagnosis to blastic phase.

Chronic myelogenous leukemia (CML) has a progressive course but little is known about the biologic characteristics of disease progression. This study was designed to assess the changes in cell proliferative characteristics, apoptosis, the expression of the bcl-2 and c-myc genes between the time of initial diagnosis and entrance into the blastic phase of the disease. We observed that the rate of cell proliferation decreased and the cell death rate did not significantly change as the disease accelerated. The level of bcl-2 expression was significantly higher in accelerated/blastic phase cells than in the chronic phase cells in the population as a whole, however, the bcl-2 expression level did not change in blast cell subpopulation. c-myc Expression was significantly higher in the blast cell subpopulation of accelerated/blastic phase than in that of earlier phases of the disease. In conclusion, the characteristics of CML cells, namely proliferation rate, c-myc and bcl-2 change during the course of the disease. It is possible that the change in c-myc expression plays a causative role in evolution of the blastic phase from the chronic phase.

Adult↗
PubMed1995

VH and VL gene usage by anti-beta-amyloid autoantibodies in Alzheimer's disease: detection of highly mutated V regions in both heavy and light chains.

In a previous study, four human IgM kappa monoclonal antibodies (mAbs) secreted by Epstein-Barr-virus-transformed B cell lines independently derived from the peripheral blood of a patient with Alzheimer's disease (AD) were found to react with a conformational epitope of beta-amyloid protein and to stain amyloid plaques in AD brain. Three of these mAbs were studied further. They did not react with an additional panel of antigens and autoantigens. By a competitive inhibition ELISA, the Kd was determined to be 5.7 x 10(-8) M. The VH and V kappa of these mAbs were sequenced at the cDNA level and found to be identical. The corresponding VH and V kappa germline counterpart genes hsigghvm148 and hsiggkvm148 were identified to be analogous to the previous reported VH3 germline gene humighvf1/dp53 and the V kappa IV germline gene hsigk18. DA1/4 and JH4b were used by the heavy chain and J kappa 4 was used by the light chain. Multiple nucleotide substitutions were seen in both VH and V kappa when their sequences were compared to the germline sequences. High replacement/silent ratios in the CDR regions of both VH and V kappa indicate positive-selective pressure. Of a total of 22 amino acid replacements in VH and V kappa, 12 were nonconservative replacements. Furthermore, 7 of these 12 resulted in charge changes. The monoreactivity, the moderately high affinity constant, the clonal expansion evident by identical VH and VL used by these B cells secreting antibodies of interest, and the excessive replacement mutations in both VH and VL segments lead to the conclusion that these antibodies have been generated due to an antigen-driven process.

Alzheimer Disease↗
PubMed1994

Interaction of tubulin with guanosine 5'-O-(1-thiotriphosphate) diastereoisomers: specificity of the alpha-phosphate binding region.

The exchangeable nucleotide-binding site of tubulin has been studied using diastereoisomers A (Sp) and B (Rp) of guanosine 5'-O-(1-thiotriphosphate) (GTP alpha S) in which the phosphorus atom to which sulfur is attached is chiral. GTP alpha S(A) (10 microM) nucleated assembly of purified tubulin (20 microM) into microtubules in buffer containing 0.1 M 2-(N-morpholino)ethanesulfonic acid with 3 mM Mg2+ and 1 mM EGTA, pH 6.6 at 37 degrees C. With 0.2 mM GTP alpha S(A), the critical concentration (Cc; minimum protein concentration required for assembly) was 8 microM tubulin. Neither 0.2 mM GTP nor GTP alpha S(B) promoted microtubule assembly in buffer with 0.5-6.75 mM Mg2+ and 20-70 microM tubulin. The Cc values for GTP alpha S-(A)-induced assembly of tubulin in buffer with 30% glycerol and of microtubule protein (tubulin and microtubule-associated proteins) in buffer were lower than for GTP. GTP alpha S(A)-induced microtubules were more stable to the cold and to Ca2+. GTP alpha S(A) and GTP but not GTP alpha S(B) bound tightly to tubulin at 4 degrees C. Although GTP alpha S(B) did not nucleate assembly, it did bind to tubulin since it was incorporated into the growing microtubule. Both isomers were hydrolyzed in the microtubules. These studies show that GTP alpha S(A) promotes tubulin assembly better than GTP and GTP alpha S(B) and that there is stereoselectivity at the alpha-phosphate binding region of tubulin. The stereoselectivity may be due to different MgGTP alpha S(A) and -(B) interactions with tubulin.

Animals↗
PubMed1994

CD40 signaling pathway: anti-CD40 monoclonal antibody induces rapid dephosphorylation and phosphorylation of tyrosine-phosphorylated proteins including protein tyrosine kinase Lyn, Fyn, and Syk and the appearance of a 28-kD tyrosine phosphorylated protein.

CD40 plays an important role in B cell activation, proliferation, and Ig class switching. The signal transduction pathway mediated by CD40 was studied using monoclonal antibody (mAb) 626.1 to CD40. Burkitt's lymphoma and Epstein-Barr virus-transformed B cell lines and tonsilar B lymphocytes were treated with the anti-CD40 mAb for various lengths of time. The early events triggered by CD40 were examined by monitoring the changes in tyrosine phosphorylation of cellular proteins with anti-phosphotyrosine mAb. Dephosphorylation of specific proteins ranging between 50-110 kD and the appearance of a 28-kD tyrosine phosphorylated protein were seen within 30 s in human B cell lines. The dephosphorylation was reversed and the 28-kD protein was dephosphorylated in cells stimulated for 1 min. In resting B cells, the appearance of the 28-kD phosphoprotein was observed in 30 s after the addition of the anti-CD40 mAb. The tyrosine phosphorylation of this protein persisted. The patterns of protein tyrosine phosphorylation differed from those induced by an anti-immunoglobulin M mAb. The changes in the state of tyrosine phosphorylation induced by the anti-CD40 mAb were obviated by mAb to CD45, a protein tyrosine phosphatase (PTP) or by the addition of sodium orthovanadate, a broad PTP inhibitor. They were also blocked by protein tyrosine kinase (PTK) inhibitors, herbimycin A and genistein, and PKC and protein serine/threonine kinase inhibitors, H7 and HA1004. In addition, the alteration in the tyrosine phosphorylation of PTKs Lyn, Fyn, and Syk was directly demonstrated. Engagement of CD40 for 30 s induced a transient decrease in tyrosine phosphorylation of these PTKs. These results indicate that the early events in CD40 signaling involve the complex interaction between PTP and protein kinases.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1994

Human rheumatoid factors with restrictive specificity for rabbit immunoglobulin G: auto- and multi-reactivity, diverse VH gene segment usage and preferential usage of V lambda IIIb.

To determine the molecular and functional properties of human rheumatoid factors (RF), we established stable hybridomas and Epstein-Barr virus-transformed B cell lines from the synovial fluid or peripheral blood of three patients with rheumatoid arthritis and one patient with systemic lupus erythematosus. 17 cell lines were obtained that produced high-titer immunoglobulin M (IgM) RF that reacted exclusively with rabbit but not human IgG or IgG of other mammalian species. Certain anti-rabbit IgG RF also had specificity for other mammalian antigens (Ag), including cytoskeletal proteins and intracellular proteins found in HeLa cells, as well as for Ag present in an extract prepared from the cell wall of group A streptococci. 13 of the 17 RF contained lambda-type light (L) chains, of which 12 were classified serologically as members of the lambda-L chain variable region (V lambda) subgroup, designated V lambda III. The heavy chain V region (VH) and V lambda sequences of nine of these IgM lambda RF were determined at the cDNA level. Five VH genes in three VH families were used by these antibodies (Ab), including VH1 (dp21/1-4b and dp10 [51p1]/hv1051), VH3 (dp38/3-15 and dp77/13-21), and VH4 (dp70/4-4b). The deduced V gene-encoded amino acid sequences of the lambda chains of these IgM lambda RF confirmed their serological classification as lambda III, and they were further classified as members of the relatively uncommon V lambda III subgroup, designated V lambda IIIb. Based on cDNA analyses, nine were the product of three different V lambda III b germline genes. Two such genes, designated hsiggll150 and hsiggll295, were cloned and sequenced from genomic DNA. Unique combinations of these VH and V lambda III b genes could be related to distinctive patterns of reactivity among the IgM lambda RF. Although the VH and V lambda regions of these Abs were expressed primarily as germline-encoded sequences, four of nine multireactive Abs had extensive V region mutation, indicative of an Ag-driven process. The finding that lambda IIIb L chains are preferentially found among anti-rabbit IgG RF, and that some of these Ab have specificity for other protein, cellular, and bacterial Ag, provides new insight into the pathogenesis of RA and related diseases.

Animals↗
PubMed1993

Human antibodies reactive with beta-amyloid protein in Alzheimer's disease.

Four human B cell lines established by Epstein-Barr viral transformation of B cells from a patient with a clinical diagnosis of Alzheimer's disease (AD) were found to secrete antibodies that react with plaques and cerebrovascular blood vessels in AD brain in a staining profile characteristic of beta-amyloid protein (beta-AP) in AD brain. Two of these antibodies were shown to be reactive with a rare plaque in a normal brain. In these studies, immunofluorescence and avidin-biotin complex immunoperoxidase methodology were used to determine antibody reaction, and thioflavine S was used to double label amyloid and neurofibrillary tangles. The four antibodies also reacted with neurons in normal and AD brain. Absorption studies, dot immunoblots, and enzyme-linked immunosorbent assays with beta-amyloid peptides 1-28 (beta-A1-28) and 1-40 (beta-A1-40) indicate the major determinant of the reactive epitope is located in the region of amino acids 1-28 of beta-AP. However, inhibition studies demonstrate a significant contribution to the antigenic determinant by the 29-40 region of the beta-A1-40. These antibodies represent the first human autoantibodies against beta-AP. The pathological significance of these autoantibodies is discussed.

Aged↗
PubMed1992

Ethacrynic acid inhibition of microtubule assembly in vitro.

Ethacrynic acid (ECA) is a sulfhydryl reactive diuretic drug. Recent studies show that ocular administration of ECA may have potential efficacy for treatment of glaucoma. ECA affects cell shape in cultured cells from the eye outflow pathway and the microtubule system is disrupted. We have studied the effect of ECA on microtubule protein (MTP) (tubulin and microtubule-associated proteins) and purified tubulin assembly. Fifty percent inhibition of MTP (1.8 mg/ml) assembly was found at 70 microM ECA in buffer and 410 microM ECA in 30% glycerol in buffer. If all sulfhydryl groups were attributed to tubulin, then approximately two sulfhydryls were blocked at 50% inhibition. Tubulin (2 mg/ml) assembly showed 50% inhibition at 175 microM ECA and approximately 2 sulfhydryl groups were lost. Increasing ECA preincubation times (0-60 min) with tubulin showed that the longer the preincubation time, the longer the lag time, and the slower the rate of assembly and that the percentage of inhibition was proportional to the ECA preincubation time. The number of blocked sulfhydryls also increased with preincubation time. Approximately two sulfhydryls were blocked at 50% inhibition of assembly. The critical concentration for assembly increased twofold when tubulin was preincubated with 0.1 mM ECA, suggesting a loss of active tubulin. Fifty percent inhibition of taxol-induced MTP and tubulin assembly occurred at 190 and 280 microM ECA, respectively, with 3.6 to 3.8 sulfhydryls blocked, respectively. Taxol protects microtubules from disassembly by ECA, suggesting that the ECA binding key sulfhydryls are blocked in the microtubule. These results suggest that ECA reacts slowly with tubulin and blocks sulfhydryl groups important for assembly. Microtubule-associated proteins and glycerol protect the sulfhydryls and so more ECA is necessary to inhibit assembly. Since the number of blocked sulfhydryls is greater at 50% inhibition for taxol-induced microtubules, sulfhydryl blocked tubulin incompetent to assemble under normal conditions may be induced to do so with taxol.

Alkaloids↗
PubMed1992

A rheumatoid factor from a normal individual encoded by VH2 and V kappa II gene segments.

OBJECTIVE: To gain insight into the immunoglobulin variable-region repertoire of anti-IgG antibodies (rheumatoid factors [RF]), we characterized the VH and V kappa gene segments utilized in an IgM-RF-secreting lymphoblastoid cell line (SSH23) isolated from a normal individual. METHODS: The cell line SSH23 was established by Epstein-Barr virus transformation of peripheral blood non-T mononuclear cells. First-strand complementary DNA (cDNA) was generated and used for polymerase chain reaction amplification of the heavy and light chain variable domains. The amplified variable domains were sequenced and compared with an extensive database of germline and cDNA V gene segments. RESULTS: The VH sequence was found to be identical to a previously described fetal VH2 incomplete cDNA and to differ by only 3 nucleotides from a JH proximal germline VH2 gene segment. To our knowledge, this is the first example of a VH2 rheumatoid factor. The V kappa 2-J kappa 4 light chain contains an uncommon 10-amino acid third complementarity-determining region (CDR 3). CONCLUSION: Utilization of preimmune fetal VH gene segments and unusual light chain junctional diversity appear to be features shared by many physiologic and pathologic rheumatoid factors.

Amino Acid Sequence↗
PubMed1988

Stereoselectivity of the guanyl-exchangeable nucleotide-binding site of tubulin probed by guanosine 5'-O-(2-thiotriphosphate) diastereoisomers.

The active site of the exchangeable nucleotide-binding site of tubulin was studied by using diastereoisomers A (Sp) and B (Rp) of guanosine 5'-O-(2-thiotriphosphate) (GTP beta S) where the phosphorus atom to which sulfur is attached is chiral. Turbidimetric measurements were used to follow kinetics, and electron microscopy was used to evaluate polymeric forms. Both isomers at 0.5 mM promoted the assembly of tubulin in buffer containing 0.1 M 2-(N-morpholino)ethanesulfonic acid, 30% glycerol, 3 mM MgCl2, and 1 mM EGTA, pH 6.6, 23-37 degrees C. GTP beta S(A) promoted assembly into microtubules, although a few bundles were also found by electron microscopy. However, GTP beta S(B) induced assembly of tubulin into bundles of sheets and microtubules. As expected, 0.5 mM GTP induced tubulin to assemble into microtubules, thin sheets, and a few bundles. Both GTP and GTP beta S(A) were hydrolyzed in the tubulin polymers. However, more than 95% of the bound GTP beta S(B) was not hydrolyzed. Higher concentrations of GTP beta S(B), i.e., 1 mM, also induced bundles of sheets and microtubules, with 86% of the thionucleotide bound as the triphosphate. The GTP beta S(B)-induced polymers were considerably more cold stable than the GTB beta S(A)-induced microtubules, which were more cold stable than GTP-induced polymers. Mg(II) (2-5 mM) had minimal effects on the structures induced by GTP beta S(A) or -(B) isomers in the tubulin assembly system. However, at 1 mM Mg(II), no assembly was found with GTP beta S(A) and tubulin.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Human antibodies to neurofibrillary tangles and astrocytes in Alzheimer's disease.

Multiple B cell lines established by Epstein-Barr viral transformation from six patients with Alzheimer's disease (AD) and six age-matched controls were screened immunocytochemically for their reactivities with AD and normal brains as well as to cell lines such as HeLa, fibroblasts and neuroblastoma. A higher incidence of reactivity with neurofibrillary tangles in situ was found among the cell lines from AD patients (23/866) in comparison with those from normals (6/803). Three cell lines from a patient with a definitive neuropathological diagnosis of AD were shown to secrete antibodies preferentially reactive with astrocytes in the grey matter of AD brain and one cell line from a normal elderly individual was shown to specifically react with neurofibrillary tangles and plaque neurites. These four antibodies were not reactive with normal brains or cell lines. These unique human antibodies may be useful in the diagnosis of AD and offer clues to its pathogenesis.

Alzheimer Disease↗
PubMed1987

Autoantibodies to neurofibrillary tangles and brain tissue in Alzheimer's disease. Establishment of Epstein-Barr virus-transformed antibody-producing cell lines.

Multiple EBV-transformed B cell lines were established from five patients with a clinical diagnosis of Alzheimer's disease (AD) and six age-matched controls. The supernatants were screened for antibody activity against SDS-treated isolated neurofibrillary tangles (NFT). Reactive supernatants were identified from both the AD and control group. The frequencies of anti-NFT antibody-secreting lines were 6.3 and 1.6% for the AD and the control groups, respectively. A proportion of these supernatants also stained NFT in situ and neurons and/or glia in sections of the frontal and the temporal cortexes of autopsied AD and normal brains, as well as cells from three cell lines (HeLa, fibroblast, and neuroblastoma). Several patterns of staining were revealed by these supernatants, indicating different reactive antigens. One supernatant stained NFT and astrocytes in sections from AD brains. It did not stain sections from two normal brains. This cell line is the result of the immortalization of a circulating B cell making antibody specific for an antigen in AD. The present approach may provide new insights in the pathogenesis of AD.

Alzheimer Disease↗