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K Hannestad

Publications and source records attributed to K Hannestad.

At least 55 records · Page 3Linked to original sources
PubMed1987

Simple rosette assay for HLA-B27 typing of whole blood samples.

Two human IgM monoclonal antibodies (TrBH12 and Tr3B6) specific for HLA-B27 were coupled to magnetic monodisperse polymer beads by spontaneous adsorption. A few minutes after mixing the beads with 50 microliter of whole blood, rosettes had formed specifically with leucocytes from HLA-B27 positive individuals. In this simple way, reliable typing for HLA-B27 could be conducted rapidly (in about 20 min) by evaluation of rosettes with an inverted microscope and ordinary light. The method requires purified monoclonal antibodies.

Antibodies, Monoclonal↗
PubMed1986

The T lymphocyte response to syngeneic lambda 2 light chain idiotopes. Significance of individual amino acids revealed by variant lambda 2 chains and idiotope-mimicking chemically synthesized peptides.

In the present study we have investigated the structure of the helper T cell (Th)-defined idiotope (Id) of myeloma protein 315 lambda 2 light chain (lambda 2(315] in BALB/c (H-2d) mice which carry a high-responder immune response gene for this Id. Three peptides were synthesized which spanned the third hypervariable region (HV3) of lambda 2(315): peptides 88-99, 94-108 and 91-108. Only peptide 91-108 was capable of eliciting carrier-specific Th that recognized M315 or free lambda 2(315). These Th did not recognize lambda 2(5-7) chain which differs from lambda 2(315) at 4 positions in this region; these are Tyr94, Ser95, Thr96, Tyr98 for lambda 2(5-7) and Phe94, Arg95, Asn96, Phe98 for lambda 2(315). Immunization with peptide analogues revealed that substitution of Tyr for Phe94 was compatible with Id-lambda 2(315) mimicry, but substitution of Ser for Arg95 or Thr for Asn96 destroyed the Th-recognized Id. Furthermore, Th primed with lambda 2(5-7) chain did not cross-react with lambda 2T952; these lambda 2 chains only differ from each other at positions 98 and 99 at the V lambda 2-J lambda 2 junction. The data indicate that individual amino acids of short peptide segments are critical for Th-recognized Id of the lambda 2 HV3 loop and V lambda 2-J lambda 2 junction. Furthermore, the immunogenicity of a small peptide suggests that the carrier (lambda 2)-specific Th recognize Id that have been processed by antigen-presenting cells (APC). This implies the existence of two categories of "internal images" of foreign or of self antigens: (a) serologically defined and (b) T lymphocyte defined. We propose that as a rule, Id processing by APC, including B cells, destroys the first and reveals the second category. The possible physiological function of these Id-specific T cells in network interactions with B cells is discussed.

Amino Acids↗
PubMed1986

Synthetic peptides and beta-chain gene rearrangements reveal a diversified T cell repertoire for a lambda light chain third hypervariable region.

Twelve L3T4+ Ly-2.2- subclones, derived from 4 independent BALB/c T cell lines, responded to a combination of the I-Ed molecule and a synthetic peptide corresponding to residues 91-108 of the lambda light chain from BALB/c myeloma protein M315 (alpha, lambda 2). Peptide analogues in which the mutated residues Arg95 or Asn96 were exchanged with the corresponding germ-line-encoded Ser95 or Thr96 had an abolished or greatly reduced capacity to stimulate T cell clones. However, responses of subclones to an analogue where the mutated Phe94 was substituted with the germ-line-encoded Tyr94 revealed three specificity patterns: 5 clones reacted only with the lambda 2(315) peptide, 6 clones responded equally well to both peptides and a single clone reacted better with the Tyr94 analogue. Analysis of the T cell receptor beta-chain gene rearrangements disclosed 7 distinct rearrangements, identical rearrangements only being found for subclones originating from the same line. At least 3 different V beta genes were used. Subclones with identical or nearly identical peptide specificity, major histocompatibility complex-restriction and alloreactivity could differ in their V beta or J beta gene segment utilization.

Amino Acid Sequence↗
PubMed1985

T helper cell recognition of idiotopes on lambda 2 light chains of M315 and T952: evidence for dependence on somatic mutations in the third hypervariable region.

Previous work has indicated that BALB/c T helper cells (Th) recognize an idiotope expressed on a 88-114/117 fragment of V lambda 2 of BALB/c myeloma protein 315. In the present study the antigenic structure of this idiotope was further analyzed. Conventional carrier-specific Th elicited by immunization of BALB/c mice with free lambda 2(315) did not cross-react with the free lambda 2 chain of the BALB/c myeloma protein T952 which differs from lambda 2(315) in five amino acid positions (38, 94, 95, 96, 99). Similarly, Th primed with free lambda 2T952 did not respond to a boost with free lambda 2(315). Thus, BALB/c lambda 2(315)-specific Th recognize an idiotope that depends on some or all of the residues at positions 94, 95, 96 and 99. Furthermore, free lambda 2T952 contains an idiotope immunogenic to Th that depends on some or all of residues 38, 94, 95, 96 and 99. Th recognition of the free lambda 2T952 idiotope was quenched upon H + L chain assembly because Th elicited by free lambda 2T952 did not respond to a boost with the complete T952 myeloma protein. In contrast to the lack of Th cell cross-reactivity, some of the antisera from BALB/c mice immunized with free lambda 2T952 cross-reacted with free lambda 2(315), free lambda lJ558 and free lambda 3CBPC49 but not with free kappa W3129 or polyclonal L chains. The H chain of T952 (alpha, kappa 2) myeloma protein was abnormally short (Mr = 48 000) and T952 existed as a halfmere probably due to this H chain deletion. Furthermore, H and L chains were disulfide bonded to each other.

Animals↗
PubMed1985

H-2-linked Ir genes have a striking influence on the immunogenicity of idiotopes of myeloma protein 315 for T helper cells.

H-2-linked immune response (Ir) genes control T helper cells (Th) that recognize idiotopes of the V domains of myeloma protein 315 as carriers; Th recognition was detected by augmentation of antibody responses of hapten (4-hydroxy-3-iodo-5-nitrophenylacetyl (NIP]-primed B cells boosted with NIP conjugated to Fab315. The present study indicates that the responder k allele of the Ir VH315 gene maps to the I-A subregion of H-2. A responder s allele of the Ir V lambda 2(315) gene on an A-strain background was identified, which also most likely maps to I-A. Although the d allele of the Ir V lambda 2(315) gene is a responder allele on DBA/2 background, the D2.GD strain (with I-region haplotype AdBbJbEbCb) was non-responder to V lambda 2(315), suggesting either that the responder d allele maps to I-E or that the b allele of a second Ir V lambda 2(315) gene located to the right of I-A exerts a strong suppressive influence. The H-2b haplotype conferred non-responsiveness to VH315, V lambda 2(315), and Fv315.

Animals↗
PubMed1984

Determinant-specific regulation of T helper cell responses to murine lambda light chains by both H-2 and non-H-2 genes.

Previous work has revealed that the T helper cell (Th) responses to an antigenic determinant of V lambda 2(315) (called lambda 2.1) is regulated by both H-2 and non-H-2 genes. In the present study this was confirmed and extended to two other determinants, one shared between free lambda 2(315) and lambda 1(J558) (called lambda 2.2) and one unique for free lambda 1(J558) (called lambda 1.1). H-2 genes regulate the responses to the latter determinants, because BALB.B (H-2b) mice were low responders and BALB/c (H-2d) mice were high responders. Thus, the H-2d haplotype on BALB/c background was associated with high responder status. However, when the H-2d haplotype was examined on other genetic backgrounds than BALB/c, the animals could be classified as either intermediate or low responders, depending upon the non-H-2 background. This demonstrated that non-H-2 genes also influenced Th responses. Furthermore, C3H-H-2o, DBA/2 and B10.D2 mice (all H-2d) responded to only one (lambda 2.1) but not the other (lambda 2.2) of two determinants physically linked on the same polypeptide chain (lambda 2(315)). This indicated that the non-H-2 gene effect is capable of fine discrimination, i.e. the non-H-2 gene-mediated low responder phenotype may at least in part be due to failure of recognition of certain antigenic sites, like the H-2-linked Ir-gene defect. F1 hybrids responded to the same determinants as their parental strains; e.g., the BALB/c non-H-2 background exerted a dominant influence over the low responder background of C3H, B10 and DBA/2 strains.

Animals↗
PubMed1984

Specificity of antibody and helper T-cell responses to the isologous myeloma protein W3129 and its subunits.

The specificity of BALB/c antibodies and Th elicited by BALB/c myeloma protein W3129 (alpha, kappa) and its subunits was studied. Antibodies were detected with RIA and ELISA techniques. Th were demonstrated by their ability to augment a secondary anti-NIP antibody response in a Mitchison type assay of adoptive immunity. The major proportion of antibodies elicited by the complete W3129 was directed to an idiotypic determinant(s) that depended on assembled H + L chains. The determinant(s) was probably located in or near the antibody combining site because binding was hapten-inhibitable. A second minor antibody population bound an idiotypic determinant(s) on VW3129H expressed on isolated H-chain as well as on the complete myeloma protein. A third and very weakly reactive set of antibodies was specific for a C alpha antigenic site(s) which was expressed much more efficiently on free than on assembled alpha-chains. The antibody response to free kappa W3129 was directed to idiotypic determinants that were inaccessible in the complete molecule. By contrast, free kappa W3129 elicited Th that responded to an idiotypic determinant(s) on VW3129K; the determinant(s) was expressed on both the isolated chain and the complete W3129, suggesting that Th responded to an idiotope not recognized by B-cells. Priming with free alpha W3129 failed in four out of five experiments to induce Th that responded to the complete W3129, demonstrating that a major difference existed between VH and VL of W3129 regarding their immunogenicity for Th. Nevertheless, free alpha W3129 did elicit antibody responses that displayed high reactivity with the complete molecule, indicating that certain serologically defined antigenic sites on the surface of W3129 are also expressed on isolated alpha W3129. Thus, certain differences were detected as to the specificities of Th and B-cells for W3129 and its subunits since they recognized separate idiotopes located in the VL- or VH-region, respectively. The pattern of Th recognition of W3129 resembled that of another isologous myeloma protein, M315, but was unlike that of a third, J558, previously described from this laboratory.

Animals↗
PubMed1983

T helper cells recognize an idiotope located on peptide 88-114/117 of the light chain variable domain of an isologous myeloma protein (315).

Isolated variable region light chain 315 (VL-315), the VL domain of a myeloma protein of BALB/c origin, induces T cells of BALB/c (H-2d) mice that help the adoptive secondary anti-4-hydroxy-3-iodo-5-nitrophenylacetyl (NIP) antibody response to NIP-Fab315. The location of the epitope recognized by helper cells was examined with two fragments of VL-315, obtained by cleavage with cyanogen bromide at Met 87. Both N-terminal fragment 1-86 and C-terminal fragment 88-114/117 elicited BALB/c antibodies that bound to the respective fragments and to VL-315. By contrast, only fragment 88-114/117, which consists of the third hypervariable region, J region, and 5-7 amino acids of the C region, induced helper cells that augmented the anti-NIP response to NIP-Fab 315.

Animals↗
PubMed1983

Recognition of lambda 1 and lambda 2 murine light chains by carrier-specific isologous T helper cells; effect of L-H chain assembly.

Previous studies from this laboratory have revealed an antigenic site located on the variable domain of the lambda 2 light chain of BALB/c myeloma protein 315 (the V lambda 2(315) site). This site is recognized by conventional carrier-specific T helper cells (Th) of BALB/c mice and is expressed on both the free and assembled V lambda 2(315) domain. The present work defines two new antigenic sites associated with murine lambda chains. The first site was associated with free lambda 1-chain of myeloma protein J558. It was recognized by splenic Th from animals that had been primed with free lambda 1J558 in complete Freund's adjuvant; when transferred to irradiated animals the primed Th responded to a boost with (4-hydroxy-5-iodo-3-nitro-phenyl)acetate (NIP)-free lambda 1J558 in saline, but did not respond to NIP-complete J558 or NIP-free lambda 2(315). Priming with complete J558 failed to elicit Th that responded to NIP-free lambda 1J558. This determinant was therefore only expressed on the free (as opposed to the assembled) form of lambda 1J558, and it was not shared with free lambda 2(315). The second antigenic site was shared between free lambda 1J558 and free lambda 2(315). It was defined by free lambda 2(315)-primed Th which responded to a boost with NIP-free lambda 1J558. Since priming with free lambda 1J558 did not elicit Th that recognized NIP-free lambda 2(315), the cross-reaction was undirectional. The free lambda 2(315)-primed Th failed to respond to the complete J558, and M315-primed Th failed to respond to NIP-free lambda 1J558, indicating that the second (cross-reactive) antigenic site, like the first, was only expressed on free lambda chains. Completely reduced and alkylated (unfolded) free lambda 1J558 and free lambda 2(315) chains elicited Th that recognized native (folded) free chains. Thus, free lambda 1J558 bears two antigenic determinants recognized by Th, one private and a second shared with free lambda 2(315). Lambda 2(315) also bears two determinants, a cross-reactive one on free lambda 2(315) shared with free lambda 1J558, and a private one located on the V lambda 2(315) domain of the complete M315. The discussion is focused on possible explanations for the quenching of the two new lambda chain determinants upon light-heavy chain assembly and why, by contrast, the private V lambda 2(315) site is maintained in the complete M315.

Animals↗
PubMed1983

Cultured human endothelial cells display an antigen that is recognized by certain human anti-chromatin autoantibodies.

Certain human anti-nucleosome autoantibodies cross-reacted specifically with an antigen on the surface of human vascular endothelial cells. This was shown by two different techniques. First, antibodies eluted from the surface of cultured endothelial cells bound to cell nuclei; this binding was inhibited by soluble mononucleosomes. Second, X-ANA, specifically isolated by their affinity to polynucleosomes, stained the plasma membranes of single cell suspensions of endothelial cells in the indirect immunofluorescence test. Several lines of evidence excluded Fc receptor-mediated binding of Ig to the cells. Thus, plasma membranes of vascular endothelial cells and chromatin bear an antigen that is serologically related.

Antibodies, Antinuclear↗
PubMed1982

Helper T cell recognition of the variable domains of a mouse myeloma protein (315). Effect of the major histocompatibility complex and domain conformation.

We have examined the recognition of the variable (V) domain of the heavy (VH) and light (V lambda 2) chains of mouse myeloma protein 315 by helper T cells. Mice were primed with the isolated V domain in complete Freund's adjuvant, and carrier (V domain)-primed spleen cells were transferred together with hapten (NIP)-primed spleen cells to recipient mice that were boosted with NIP3-Fab-315. The helper cell response to both domains was governed by H-2-linked immune response (Ir) genes, and VH-315 and V lambda 2 displayed different Ir phenotypes. H-2k conferred high responsiveness to VH on three different genetic backgrounds, BALB/c, C3H, and B10; mice of the d and b haplotypes were low responders. Conversely, H-2d conferred high responsiveness to V lambda 2 on two backgrounds, BALB/c and C3H, whereas mice of the k haplotype were low responders to this domain. Non-H-2 genes of the B10 background extinguished the helper cell response to V lambda 2 in animals with the high responder d haplotype. The VH Ir gene mapped to the K-A interval of the H-2 complex. Unfolded (completely reduced and alkylated) V domains primed helper cells as efficiently as folded domains for responses to NIP3-Fab-315, indicating that the helper cells recognized an antigenic determinant that was not conformation-dependent. The data indicate that there exists helper T cells which recognize each member of the M315 pair of V domains independent of the other, and that these V domains are recognized like conventional extrinsic protein antigens.

Animals↗
PubMed1982

Histones synthesized for use in early development of Xenopus laevis are stored as a complex with antigenic properties similar to those of the octamer core of nucleosomes.

Serum of patients with systemic lupus erythematosus (SLE) contains crossreacting autoantibodies which recognize histones in nucleosomes or when they are induced to form octamers in solution in the presence of 2 M NaCl, but not when they are dissociated free in solution at physiological ionic strength. We have found that histones stored in eggs of Xenopus laevis for use in rapid nuclear synthesis during early development react with this antibody. This reaction has been observed by radioimmunoassay, inhibition of chromatin assembly by the extracts in the presence of antibody, and, in a preliminary result, by identification of a histone-antibody complex bound to protein A-sepharose. Further evidence that the extract antigen corresponds to the stored histone pool comes from sedimentation and charge fractionation experiments where the chromatin assembly activity and antigen (measured by radioimmunoassay) were found to cofractionate. BEcause the extract histones are not bound to DNA, our results suggest that they are stored as a soluble complex in a conformation similar or identical to the octameric core of the nucleosome. Our data suggest that the histones in this complex are bound to an anionic factor or factors which presumably replaces the DNA in shielding the positive charges on the histones.

Animals↗
PubMed1981

Lupus erythematosus (LE) factors recognize both nucleosomes and viable human leucocytes.

The morphological LE test was completely inhibited by mixing LE-factor-positive sera with core mononucleosomes, the basic histone-DNA subunit of chromatin. Free DNA and free histones at physiological ionic strength were not inhibitory. The LE-factor-binding antigen was virtually completely regained by mixing DNA and the inner histones H2A, H2B, H3 and H4 in 2 M NaCl, followed by step dialysis to 0.15 M salt. Trypsin-digested core mononucleosomes did not inhibit the LE test, indicating that the antigenic site is located on the N-terminal region of the histones. Twenty-six out of twenty-seven LE-factor-positive sera contained antinuclear antibodies that cross-reacted with plasma membranes of viable leucocytes (referred to as X-ANA). By contrast, weak X-ANA activity was found in only two out of twenty-five LE-factor-negative sera with high ANA titres. Three LE-factor-positive sera were subjected to absorption with viable human leucocytes, which led to the complete disappearance of LE factor activity of all three sera. The data indicate that antibodies with LE factor activity recognize core mononucleosomes and a plasma membrane antigen of viable human leucocytes.

Absorption↗
PubMed1980

Human autoantibodies that react with both cell nuclei and plasma membranes display specificity for the octamer of histones H2A, H2B, H3, and H4 in high salt.

Sera of some patients with systemic lupus erythematosus and related diseases contain a polyclonal antibody population (cross-reactive antinuclear antibodies [X-ANA]) that react specifically with both core mononucleosomes and plasma membranes of viable nucleated cells. Native mononucleosomes and nucleosome cores assembled from long DNA and the inner histones were indistinguishable in terms of inhibition of binding of X-ANA to nuclei of tissue sections and to polynucleosomes on the walls of plastic tubes. In contrast, mononucleosomes selectively depleted of histones H2A and H2B did not inhibit these reactions. A method was developed for isolation of X-ANA from serum that took advantage of the dual specificity of these antibodies. Immunosedimentation in sucrose density gradients revealed that 125I-labeled Fab' fragments of highly pure X-ANA formed complexes with the inner histones H2A, H2B, H3, and H4 in 2 M NaCL, but not in 0.15 M salt. These results indicate that X-ANA recognize an epitope of the inner histone in 2 M salt, and that in 0.15 M NaCL this epitope is not formed unless the histones interact with DNA to generate a nucleosome structure. Furthermore, in light of the previous demonstration that the epitope is destroyed by trypsin, it may be localized in the N-terminal region of histone H2A or H2B.

Antibodies, Antinuclear↗
PubMed1980

H--2-linked genes control immune response to V-domains of myeloma protein 315.

Immunoglobulins function as antigen receptors of B lymphocytes and as effector molecules for elimination of foreign antigens. Recently, other functions have been revealed: for example, idiotypes (antigenic sites of variable (V) domains) bound on the surface of plasmacytomas can act as tumour-specific transplantation antigens. Moreover, optimal maturation of B lymphocytes of a given idiotype into antibody-secreting cells seems to require assistance from two different kinds of helper T cells (Th), one bearing receptors complementary or similar to that idiotype, and another that recognizes the antigen. To learn more about recognition of V regions by Th, we have used V-domains of the immunoglobulin A (IgA) (lambda 2) myeloma protein M315 produced by the BALB/c plasmacytoma MOPC315 (ref. 7) as carriers for anti-hapten responses. We report here that the Th response to the V-domain of the heavy chain (VH) and the light chain (VL) of M315 seems to be under H--2-linked immune response (IR) gene control.

Animals↗
PubMed1980

Immunization with the light chain and the VL domain of the isologous myeloma protein 315 inhibits growth of mouse plasmacytoma MOPC315.

Prior immunization of BALB/c mice with free light chains from myeloma protein 315 (L315) and its variable domain (VL315) inhibited the growth of subcutaneously injected MOPC315 tumour cells. The growth suppression observed after immunization with L315 was equivalent to that which resulted from immunization with the complete M315. VL315 and non-polymerized L315 did not elicit specific antibodies. Polymerized L315 induced both suppression of MOPC315 growth and antibodies specific for free L315; however, these antibodies did not react with the complete M315, nor were they absorbed by MOPC315 tumour cells. The data indicate that the suppression of tumour growth was mediated by specifically sensitized cells acting in the absence of antibodies against M315 or L315. Immunization with the variable domain of the heavy chain from M315 (VH315) had no effect on the growth of MOPC315. The M315 fragments and subunits that induced growth suppression were thus identical with those capable of inducing T helper cells in BALB/c mice.

Animals↗
PubMed1979

T helper lymphocytes recognize the VL domain of the isologous mouse myeloma protein 315.

The localization of a major determinant on an isologous myeloma protein (M315) which stimulates BALB/c helper T cells was investigated. Augmentation of the adoptive secondary antibody response to NIP-M315 and the idiotype of M315 (Id315) was used as an indicator of helper effects. Spleen cells primed with the light chain of M315 (L315) and its V-domain (VL315) were highly efficient helpers; priming with the fragment containing the two V-domains of M315 (FV315) induced a somewhat weaker helper effect than L315 or VL315. The helper effect was abolished or markedly reduced by treating the primed cells with rabbit anti-brain theta + C. Cells primed with the heavy chain of M315 (H315) effected weak but significant help. The V-domain of H315 (VH315) was incapable of eliciting cells with detectable helper effect. The data indicate that the VL315 embodies a major determinant for T helper lymphocytes. This determinant is expressed on the free VL315 as well as on the complete M315. In contrast, previous studies have shown that BALB/c antibodies produced against Id315 recognize antigenic sites that are only displayed on associated (VL315 + VH315) domains.

Animals↗