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H Slor

Publications and source records attributed to H Slor.

At least 37 records · Page 2Linked to original sources
PubMed1989

Detection of antimitochondrial antibodies: characterization by enzyme immunoassay and immunoblotting.

Mitochondrial antigens were purified from rat liver and characterized by immunoblotting. Sera from 19 well defined patients with primary biliary cirrhosis (PBC) reacted with two mitochondrial polypeptides of 68 Kd and 45 Kd. Antibodies to these antigens were not detected in any of the sera of patients with cirrhosis of the liver, chronic active hepatitis or other autoimmune diseases. The two polypeptides were derived from the soluble fraction of the mitochondrial matrix. An enzyme-linked immunosorbent assay (ELISA) employing these rat liver mitochondrial antigens is described. Positive results were obtained with all except one PBC sera (95%), five out of 47 patients with cirrhosis (11%), one out of 20 patients with chronic active hepatitis (5%), and two out of 19 patients with various autoimmune disorders (11%). The titers detected in PBC were markedly higher than those recorded in patients with other liver and autoimmune diseases. Strong correlation was found between immunoblotting and the ELISA in determining antimitochondrial antibodies. The ELISA presented is easily performed and seems to be a useful diagnostic tool for antimitochondrial antibodies in patients with PBC.

Adolescent↗
PubMed1989

The detection of anti-Sm-RNP activity in sera of patients with monoclonal gammopathies.

The sera of 141 patients with monoclonal gammopathies were examined for the presence of anti-RNP and anti-Sm activities. An enzyme-linked immunosorbent assay (ELISA) was employed. Thirty-two sera were found to bind RNP while 16 bound to Sm. The anti-Sm and anti-RNP antibodies were found in sera of patients with IgG, IgM and IgA gammopathies. The activity against RNP and/or Sm was confirmed further by using purified immunoglobulins, employing competition assays and immunoblotting. Anti-Sm antibodies are regarded as being highly specific for SLE, yet none of the patients whose serum was found to contain high titres of anti-Sm/anti-RNP antibodies presented with symptoms related to SLE or other rheumatic diseases. Our results of a high incidence of anti-ribonucleoproteins activity in the serum of patients with monoclonal gammopathies support previous reports of autoantibody properties characteristic of these immunoglobulins.

Antibodies, Antinuclear↗
PubMed1989

Natural autoantibodies in the serum of healthy women--a five-year follow-up.

Autoantibodies are often found among healthy individuals. The significance of these findings, regarding the potential development of overt autoimmune disease and the severity of such an eventuality, is as yet unclear. In order to elucidate these issues 506 healthy women were screened and 60 women of child-bearing age were found to posses high titres of various anti-nuclear antibodies. After a 5-year follow-up, 57 of these 60 women were found to have autoantibodies to a variety of autoantigens. Seven of the women had some symptoms that could be associated with the presence of the antibodies (i.e. arthritis, multiple abortions, Raynaud's phenomenon), however, none exhibited overt clinical signs of an autoimmune disease. Our study may point to the fact that in normal subjects (women aged 22-44 years) high titres of natural autoantibodies are not necessarily indicative of a high risk of developing an overt autoimmune condition, at least for a follow-up period of 5 years.

Adult↗
PubMed1989

Autoantibody production by patients infected with Leishmania.

Sera from 29 patients with visceral leishmaniasis and 14 patients with cutaneous leishmaniasis were tested against a panel of nine nuclear antigens employing an enzyme-linked immunosorbent assay (ELISA). Anti- Sm, RNP, SS-A and SS-B antibodies were present in high titres in 83, 86, 36 and 73 per cent of the patients with visceral leishmaniasis and in 7, 14, 25 and 25 per cent of the patients with cutaneous leishmaniasis. One serum from a patient with visceral leishmaniasis which reacted strongly with Sm, RNP, SS-A and SS-B was examined by immunoblotting on extractable nuclear antigen from Hela cells. This serum binds to nine different antigenic bands (16, 23, 29, 30, 40, 50, 58, 100 and 115 kD). These same antigens were recognized by serum from a patient with systemic lupus erythematosus. The binding of visceral leishmaniasis serum antibodies to ribonucleoproteins was inhibited by prior incubation of serum with either leishmanial membrane antigens, from four different species of Leishmania, or intact cells of Leishmania donovani, implying molecular resemblance between common leishmanial antigens and ribonuclear antigens. It seems that appearance of autoantibodies to ribonucleoproteins in sera of patients infected with Leishmania is not only due to simply polyclonal activation of lymphocytes, but is also the result of a molecular mimicry between leishmanial antigens and ribonucleoproteins.

Antibodies, Antinuclear↗
PubMed1986

Concanavalin A receptor capping in mouse myeloma and hybridoma.

Concanavalin A capping was studied in immunoglobulin-secreting hybridomas derived from fusion of mouse myeloma NSO cells with mouse spleen lymphocytes. The cells of the parental populations differed significantly in capping ability (low in myeloma cells and high in the lymphocytes). Among the hybridoma cells tested, several clones showed low capping, similar to that of the myeloma cells, some showed a good degree of capping, similar to that of the lymphocytes and other clones expressed an intermediate capping response. Capping was significantly increased in hybridoma clones of intermediate capping ability following in vivo intraperitoneal growth. A possible relationship of the variation in capping response to cell motility and to metastatic capacity is pointed out.

Animals↗
PubMed1985

Effect of DNA conformation on the binding of antibodies to benzo[a]pyrene diol-epoxide DNA adducts.

The effect of the helical conformation of DNA on the binding of antibodies to DNA-carcinogen adducts was evaluated. The efficiency of antibody binding to adducts produced in DNA by treatment with (+)-trans-7 beta, 8 alpha-dihydroxy-9 alpha, 10 alpha-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE) was modulated by varying the winding angle of the DNA helix using heat denaturation, organic solvents, and cations. Unwinding and complete denaturation of the DNA helix increased the binding efficiency of anti-bodies to DNA-BPDE adducts 4- to 8-fold over that to BPDE adducts in the unperturbed double helical DNA. The antibody binding efficiency increased in proportion to the degree of unwinding of the double helix induced by dimethylsulfoxide, ethylene glycol, or glycerol. Conversely, winding of the double helix with monovalent cations (Na+, K+, Rb+, Li+, Cs+ and NH4+) and more effectively with divalent cations (Mg2+, Ca2+, Mn2+, Sn2+ and Ba2+) decreased antibody binding to DNA-BPDE adducts. We suggest that the molecular orientation of BPDE adducts within helical grooves modulates adduct accessibility for binding with antibody molecules. By the opening and/or unwinding of the helix, BPDE adducts (or their immunogenic sites) partially "buried" within the grooves may be exposed to varying degrees for antibody binding. Conversely, winding of the helix shielded the BPDE adducts from antibody recognition and binding.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗
PubMed1983

The binding of a carcinogen to the nucleosomal and non-nucleosomal regions of the simian virus 40 chromosome in vivo.

The effect of chromatin structure on the binding of a chemical carcinogen to the genomic DNA was studied. The binding in vivo of the ultimate carcinogen, benzo-pyrene 7,8,-diol,-9,10-epoxide, to various regions of the SV40 chromosome was revealed by an immunological method. Particular attention was given to restriction fragments which include the origin of replication which is "non-nucleosomal" in a significant fraction of the chromosomes. The distribution of (+/-) trans-7,8-dihydrobenzo[alpha]pyrene-7,8-diol-9,10-epoxide (BPDE) adducts was studied in 1) SV40 DNA modified in vitro to a level of 20 adducts/molecule, 2) DNA from SV40 chromosomes modified in vivo to a level of less than 1 adduct, and 3) DNA from only those chromosomes with an open origin of replication. In other experiments, the binding of BPDE to the origin region was compared to the binding to nucleosome core particle DNA from the viral chromosome. The origin region bound 1.7-fold more BPDE than core DNA, while linker DNA is 3-fold more modified than core DNA. However, the origin region was only about 20% more modified than any other region of the chromosome. We conclude that while the conformation of the DNA in chromatin has a slight effect on its accessibility to the carcinogen, the SV40 chromosome does not contain a particular "hot spot" which is preferentially modified by BPDE.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗
PubMed1983

Immunological detection of carcinogen-modified DNA fragments after in vivo modification of cellular and viral chromatin.

Antibodies specific for DNA modified by (+/-)-trans-7, 8-dihydrobenzo(a)pyrene-7,8-diol-9, 10-epoxide have been used to quantitate the relative modification level in fragments derived from pBR322 DNA from cellular DNA and in the coding and noncoding strands of simian virus 40 DNA. DNA fragments with a covalent molar modification level ranging from less than 1 to over 200 are resolved by agarose gel electrophoresis and transferred to diazobenzyloxymethyl cellulose paper. The paper is incubated with antibodies specific to carcinogen-modified DNA, and the location of the antibody is visualized by autoradiography after incubation with 125I-protein A. The binding of antibodies is directly proportional to the level of DNA modification. Using this technique, we find that linker DNA is about 2.5- to 3-fold more accessible to (+/-)-trans-7,8-dehydrobenzo(a)pyrene-7, 8-diol-9, 10-epoxide than nucleosomal core DNA and that under in vivo conditions the coding and noncoding strands of the simian virus 40 chromosome are equally accessible to trans-7,8-dihydrobenzo[a]pyrene-7,8-diol-9, 10-epoxide. The approach described allows assessment of the relative level of modification in any DNA sequence which can be subjected to gel electrophoresis.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗
PubMed1981

Purification of a nuclease from human serum.

The purification procedure for a nuclease from human serum is described. It includes ammonium sulfate precipitation, chromatography on DEAE-Sephadex and on Sephacryl-S 200, and preparative electrophoresis. The enzyme purified about 2000-fold, is homogeneous in a sodium dodecyl sulfate electrophoretic system, where it has a mol. wt of 78,000. The pH optimum lies around pH 6.5; it is a sugar-nonspecific endonuclease.

Deoxyribonucleases↗