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K Hannestad

Publications and source records attributed to K Hannestad.

At least 73 records · Page 4Linked to original sources
PubMed1979

Properties of antinuclear antibodies that cross-react with plasma membranes.

Certain human antinuclear antibodies (ANA) cross-react specifically with the surface membrane of human leucocytes. In the present work these cross-reacting (X) ANA could be eluted directly from viable leucocytes isolated from three patients. The plasma membrane antigen recognized by X-ANA appeared phylogenetically highly conserved since it was present on viable HeLa cells and cells from mouse and rabbit spleen, rat liver, and the slime mould Physarum polycephalum. X-ANA did not react with the plasma membrane of nucleated bird erythrocytes or human erythrocytes or thrombocytes. The same X-ANA subset reacted with the various cells. The presence of X-ANA correlated strongly (P less than 0.01) with antibodies against a HeLa cell surface antigen. The nuclear antigen recognized by X-ANA was present in all species examined, including bird erythrocyte nuclei and nuclei of Physarum polycephalum. Native or denatured DNA, RNA or a saline extract of nuclei did not inhibit the binding of X-ANA to cell nuclei.

Animals↗
PubMed1979

The plasma cell differentiation antigen PC.1 is absent in CH3/Tif and present in C3H/HeJ.

(C3H/TifxDBA/2)F1 mice, immunized with viable BALB/c plasmacytoma MOPC315 cells, produce antibodies directed against a cell-surface antigen. The strain and tissue distribution of this antigen was identical to that of the plasma cell differentiation alloantigen PC.1. The antigen is absent in the mouse strain C3H/Tif but is present in the closely related substrain C3H/HeJ. This is the third difference between surface structures of the B-cell lineage of C3H/Tif and C3H/HeJ mice.

Animals↗
PubMed1979

The specificity of human autoantibodies that react with both cell nuclei and plasma membranes: the nuclear antigen is present on core mononucleosomes.

We have examined the nature of the nuclear antigen recognized by certain natural human antibodies that react specifically with both cell nuclei and plasma membranes from many species. Partial purification of these antibodies, called X-ANA, is achieved by binding to and rapid elution from the surface of viable human leukocytes. Chicken erythrocyte chromatin was solubilized by digestion with staphylococcal nuclease and fractionated into a 0.15 M NaCl soluble fraction that consisted of core mononucleosomes lacking H1/H5, and a 0.15 M NaCl insoluble fraction composed of polynucleosomes with H1/H5 present. No proteins other than histones were detected. Native and reconstituted mononucleosomes displaced IgG of the leukocyte eluates from nuclei of frozen mouse kidney sections and from the walls of plastic tubes coated with polynucleosomes. The reconstituted core mononucleosomes were 4- 10-fold less efficient inhibitors than native mononucleosomes. Trypsin digested mononucleosomes, free high m.w. DNA, and free histones displayed no or very weak inhibitory activity. The data indicate that X-ANA recognize a complex consisting of the core histones H2A, H2B, H3, H4, and DNA of 140 to 200 base pairs in length.

Antibodies, Antinuclear↗
PubMed1978

Certain rheumatoid factors react with both IgG and an antigen associated with cell nuclei.

Rheumatoid factors (RF) were isolated by their affinity for human IgG. RF from three out of twenty-four sera (12%) with a RF-latex titre greater than or equal to 20 and an anti-nuclear antibody (ANA) titre greater than or equal to 250 cross-reacted with nuclei from mouse cells. This antibody which represents an unknown proportion of RF, is designated RF/ANA. Only one of the three sera (Nil) contained large amounts of RF/ANA. A fourth serum (Jos) had 6.6 mg of RF per ml and an ANA-titre of 4096; all the ANA-activity of this serum was absorbed by an IgG-agarose conjugate. Part of the RF-activity of serum Jos was carried by antigenically deficient IgM. The ANA-activity of purified RF/ANA from four sera was inhibited by low concentrations of aggregated human IgG and by higher concentrations of human Fcgamma fragments and non-aggreated mouse anti-DNP antibodies. The data provide strong support for the conclusion that certain antibody molecules can combine with both IgG and an antigen in cell nuclei.

Antibodies, Antinuclear↗
PubMed1977

In vivo growth advantage of the MOPC-315 mouse myeloma over its immunoselected variants.

Myeloma cells of the "wild type" that produce complete immunoglobulin molecules and those of the more usual variant type that display only one kind of chain [either light (L) or heavy (H)] were cocultivated ip and sc in syngeneic BALB/c mice. With each of six deliberately selected variants, a progressive increase in the proportion of wild-type cells was observed; the rate of change suggested that these variants had an approximately 10% slower growth rate than that of the wild-type tumor. In contrast, a variant that arose spontaneously overgrew the wild-type cells. The results may account for a) the stable capacity of most wild-type tumors to produce complete immunoglobulin molecules (L- plus H-chains) over many years, even though they frequently generate variant cells that produce only L- or only H-chains; and b) the occasional spontaneous change of myeloma cell populations from predominantly wild-type to variant cells.

Animals↗
PubMed1977

Ligand-induced redistribution and augmentation of surface-bound myeloma protein on MOPC 315 plasmacytoma cells.

The dinitrophenyl (DNP)- and trinitrophenyl (TNP)-binding IgA(lambda2) myeloma protein M315, bound on the surface of MOPC315 mouse plasmacytoma cells, was redistributed into spots, patches, and, more rarely, into caps by TNP14-BSA and by divalent but not monovalent anti-M315 antibodies. Antiserum to the L-chain of M315 (L315) induced similar redistribution of L315 bound on the surface of variant cells that only produced L315. The spots were much larger and more brilliant when the cells were incubated with the ligands at 37 degrees C than at 4 degrees C. Redistribution of M315 also occurred on M315-producing cells in peritoneal diffusion chambers incubated in BALB/c mice producing antibodies against the M315 idiotype. The clearance of immune aggregates and the regeneration of new surface-bound M315 in diffusion chambers were much slower for MOPC315 cells than that reported for B lymphocytes. The total pool of M315 was 1.9 pg per cell (about 8 x 10(6) 7S molecules), but only an average of 6 x 10(3) [125I]TNP-BSA molecules were bound on the surface of each MOPC cell at 4 degrees C. The amount of surface-bound TNP-BSA increased eightfold when the cells were preincubated at 37 degrees C with rabbit anti-mouse IgA; at 4 degrees C the increase was only twofold. The data indicate that multivalent ligands specific for M315 induce an accumulation of M315 on the cell surface that correlates with secretion; the immediate precursors of secreted myeloma protein may be arrested in their transit through the membrane by the ligands.

Animals↗
PubMed1977

Certain polyclonal antinuclear antibodies cross-react with the surface membrane of human lymphocytes and granulocytes.

Five out of 24 human sera with antinuclear antibody (ANA) titers of 1250 or more contained ANA that bound in vitro to normal viable human mononuclear blood cells and granulocytes, but not to erythrocytes. The antibodies can be eluted off from the cell membranes and shown to possess ANA activity. Antinative DNA antibodies and lupus erythematosus factor were not recovered in eluates, indicating that they did not react with the cells. The cells absorbed 75%-87% of the ANA activity from three sera. ANA reacted with both T-lymphocyte-depleted and -enriched mononuclear cells. No or minimal amounts of ANA bound to mouse spleen cells in suspension; in contrast, the ANA eluted from human cells reacted with nuclei of smeared mouse spleen cells. The cross-reacting antibodies were predominantly IgG that bound well at 37 degrees C, and F(ab')2 fragments carried both activities. The ANA-binding plasma membrane antigen was resistant to trypsin and RNAse but was completely inactivated by glutaraldehyde. The data indicate that human leukocyte plasma membranes and cell nuclei from many species contain a cross-specific antigen. Alternatively, the antigen may be produced in the nucleus and somehow attach to the plasma membrane.

Antibodies, Antinuclear↗
PubMed1977

Production of BALB/c anti-idiotypic antibodies against the BALB/c myeloma protein 315 does not require an intact ligand-binding site.

To determine whether the ligand-binding site of the BALB/c myeloma protein 315 is essential for the anti-idiotypic response in syngeneic animals, 17 BALB/c mice were immunized with M315 that had been affinity-labeled with bromo-acetyl-DNP-L-lysine (BADL). Essentially all the active sites of M315 were blocked by the affinity label. Fourteen mice produced antibodies that reacted with an idiotypic determinant localized in the Fv fragment of M315, but this idiotype was not part of the DNP-lysine-binding site, and it was absent from L315 and H315 chains. Two groups of BALB/c mice were immunized with nonaffinity-labeled M315, to determine whether the same idiotype was recognized with this immunogen. All animals in the group that received the most prolonged immunization produced antibodies that could be divided in two populations: about 75% were directed against the site-associated idiotype, and the rest reacted with the nonsite idiotype. The other group produced antibodies exclusively specific for the site. Thus, the site-associated idiotype of M315 is not essential for the antibody response of BALB/c mice against M315, and M315 carries at least two different idiotypes that can be recognized by B cells of syngeneic animals.

Animals↗
PubMed1977

Acid elution of blood group antibodies from intact erythrocytes.

Human IgM and IgG antibodies against blood group antigens (A, B, D, C, c, E, e, Fya, K), autoantibodies and mouse IgM and IgG antibodies against sheep erythrocytes have been eluted from intact human and sheep red cells by glycine-HCl buffer, pH 3.0. The yield of human antibodies was higher with acid than with heat and ether elution, and the contamination of hemoglobin in the eluate was negligible. The acid elution method is very simple and rapid and, therefore, highly suitable for experimental as well as routine immunohematological work.

ABO Blood-Group System↗
PubMed1976

Polyclonal human antibodies to IgG (rheumatoid factors) which cross-react with cell nuclei.

Antibodies to human IgG (rheumatoid factors (RF) from serum Han resembled the 'intermediate' complexes of sera from some patients with rheumatoid arthritis. These RF were isolated from heat-inactivated serum by affinity chromatography on agarose-coupled human IgG. Indirect immunofluorescence revealed that the isolated RF cross-reacted with cell nuclei from many species. Virtually all the antinuclear factor (ANF) activity of this serum was extracted by IgG-agarose. Alternative explanations of this phenomenon, such as nonspecific binding of a separate population of ANF, binding of ANF to the immunosorbent via an IgG RF-IgG ANF immune complex, or presence of nuclear antigens on the immunosorbent, were ruled out. The cross-reacting antibodies possessed both kappa and lambda light chains and predominantly gamma and some mu heavy chains, indicating that they were of polyclonal origin. The antinuclear activity was present in the F(ab')2 fragments. The interpretation of this strange cross-reaction is briefly discussed.

Antibodies, Antinuclear↗
PubMed1972

Cell-bound myeloma proteins on the surface of myeloma cells: potential targets for the immune system.

Rosette formation with 2,4,6-trinitrophenylated (Tnp)-sheep erythrocytes was used to demonstrate cell-bound myeloma proteins on cells from each of the eleven mouse plasmacytomas tested. Tnp-erythrocytes were bound directly by cells from two tumors (MOPC-315 and MOPC-460) that formed myeloma proteins with antihapten combining sites; rosette formation with cells from the other tumors required hybrid antibody fragments with one site specific for Tnp and the other specific for an appropriate immunoglobulin on the tumor cell surface. The cell-bound immunoglobulin of MOPC-315 and of MOPC-460 had the same heavy and light chains, idiotypic determinants, and ligand-binding specificities as the respective myeloma proteins secreted by these tumors. A variant tumor (MOC-315 NR) was grown from the small proportion of MOPC-315 cells (5-10%) that did not bind Tnp-erythrocytes directly: this tumor secreted only the light chain of protein 315, carried this chain on the cell surface, and resembled the variant tumors that arose, probably by immunoselection, in BALB/c mice challenged with MOPC-315 cells while making an immune response to the idiotype of protein 315.

Animals↗