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Biomedical subjects

R van der Zee

Publications and source records attributed to R van der Zee.

At least 73 records · Page 4Linked to original sources
PubMed1993

Successful primate immunization with peptides conjugated to purified protein derivative or mycobacterial heat shock proteins in the absence of adjuvants.

We have previously shown in mice that antibodies can be induced to synthetic malaria peptides conjugated to mycobacterial antigens, such as purified protein derivative (PPD) or heat shock proteins (hsp), and given in the absence of adjuvants after a previous priming with bacille Calmette-Guérin (BCG). In the present study we investigated this model of immunization in the non-human primates, Saimiri sciureus monkeys. Monkeys primed with BCG subcutaneously and then immunized subcutaneously with the Plasmodium falciparum sporozoite (NANP)40 synthetic peptide conjugated to PPD or mycobacterial hsp of 65 or 70 kD, in the absence of adjuvants, produced antipeptide and anti-sporozoite IgG antibodies. Interestingly, the carrier effect of the hsp of 70 kD for the induction of anti-(NANP)40 antibodies was also observed in the absence of a previous priming with BCG. These data suggest that such a vaccination strategy may be applied to humans.

Adjuvants, Immunologic↗
PubMed1993

Antibodies to human HSP60 in patients with juvenile chronic arthritis, diabetes mellitus, and cystic fibrosis.

The 60-kD heat shock protein (hsp60) has been implicated in the etiology and pathogenesis of both experimental and naturally occurring autoimmune diseases such as juvenile chronic arthritis (JCA). Human hsp60 is expressed in inflamed synovial tissue, and T lymphocytes both from peripheral blood and synovial fluid show reactivity to human hsp60. Because the anti-hsp60 B lymphocyte response has been less well studied, we have determined the occurrence of IgG anti-human hsp60 antibodies in patients with JCA and various other autoimmune diseases of childhood. Serum IgG anti-human hsp60 antibodies in JCA patients were significantly higher compared with control children (358 and 163 U/mL, respectively). Within the group of JCA patients, the highest antibody titers were found in the subgroup with a polyarticular onset of JCA. IgG anti-human hsp60 antibody levels in synovial fluid were 3- to 4-fold higher compared with paired serum samples. Because this difference was not found for total IgG or for irrelevant antibodies (anti-polyribosylribitol phosphate), this suggests local anti-hsp60 antibody production in the synovial compartment. The occurrence of anti-hsp60 antibodies is not specific for JCA but also is found in children with systemic lupus erythematosus and in cystic fibrosis, whereas mixed connective tissue disease and insulin-dependent diabetes are negative in this respect. Whether the anti-human hsp60 antibodies are directed toward species-specific sequences or to conserved sequences of the hsp60 molecule remains to be determined.

Adolescent↗
PubMed1992

Disease inhibition by major histocompatibility complex binding peptide analogues of disease-associated epitopes: more than blocking alone.

Peptide analogues of disease-associated epitopes were studied for inhibition of experimental allergic encephalomyelitis (EAE) and adjuvant arthritis (AA) in Lewis rats. EAE- and AA-associated analogues were selected as competitors because of their in vitro inhibitory activity on proliferation of encephalitogenic and arthritogenic T cells. Although the EAE-associated competitor had a superior major histocompatibility complex (MHC) binding affinity, the AA-associated competitor was a better inhibitor of the in vitro proliferation of arthritogenic T cells. Furthermore, although in vivo EAE was inhibited by both competitors, AA was only inhibited by the AA-associated competitor. Remarkably, in contrast to what was expected of a regular MHC competitor peptide, the AA-associated peptide analogue also prevented AA upon immunization before disease induction and appeared to induce T cell responses that crossreacted with the original disease-associated epitope. Therefore, it is concluded that antigen-specific regulatory mechanisms were involved in synergy with MHC competition. The integration of both qualities into a single "competitor-modulator" analogue peptide may lead to the development of novel, more effective, disease-specific immunomodulatory peptides.

Alanine↗
PubMed1992

Two monoclonal antibodies generated against human hsp60 show reactivity with synovial membranes of patients with juvenile chronic arthritis.

Heat-shock proteins have been shown to be critical antigens in a number of autoimmune diseases. In human arthritis and in experimentally induced arthritis in animals, disease development was seen to coincide with development of immune reactivity directed against not only bacterial hsp60, but also against its mammalian homologue. We have developed murine monoclonal antibodies after immunization with recombinant human hsp60. Antibodies with unique specificity for mammalian hsp60, not crossreactive with the bacterial counterpart (LK1), and antibodies recognizing both human and bacterial hsp60 (LK2) were selected. Both antibodies recognize epitopes located between amino acid positions 383 and 447 of human hsp60. In immunogold electron microscopy, the mitochondrial localization of hsp60 in HepG2 cells was shown. Furthermore, both LK1 and LK2 showed a raised level of staining in light microscopy immunohistochemistry of synovial membranes in patients with juvenile chronic arthritis. The increased staining for LK1, with a unique specificity for mammalian hsp60, thus unequivocally demonstrates that this is due to a raised level of expression of endogenously produced host hsp60 and not to deposition of bacterial antigens.

Antibodies, Monoclonal↗
PubMed1992

Juvenile rheumatoid arthritis patients manifest immune reactivity to the mycobacterial 65-kDa heat shock protein, to its 180-188 peptide, and to a partially homologous peptide of the proteoglycan link protein.

Immune reactivity to the 65-kDa mycobacterial heat shock protein (hsp65) has been associated with arthritis in rats and humans. In this report we evaluated patients with juvenile rheumatoid arthritis for such immunity. A high proportion of affected children showed both antibody and T lymphocyte responses to hsp65 and to two related peptides: the nonapeptide 180-188 sequence of hsp65 and a partially homologous peptide of the cartilage proteoglycan link protein. The titer of circulating antibodies was generally higher in patients with clinically active disease. In contrast to the juvenile rheumatoid arthritis patients, patients with adult rheumatoid arthritis tended to have lower responses of their peripheral blood T lymphocytes to the whole hsp65 molecule. Moreover, the adult rheumatoid arthritis patients did not respond to the peptides. Thus, there appear to be immunological differences between juvenile and adult forms of rheumatoid arthritis related to hsp65 reactivity.

Adolescent↗
PubMed1992

Towards peptide immunotherapy in rheumatoid arthritis: competitor-modulator concept.

By the introduction of single-amino acid substitutions in well-defined T cell epitopes of autoimmunogenic proteins, e.g., mycobacterial heat shock protein (hsp60) in adjuvant arthritis (AA) and myelin basic protein (MBP) in experimental allergic encephalomyelitis (EAE), efficiently blocking MHC binding peptides were selected. Despite the finding that a substituted variant of epitope 180-188 of hsp60 was 'blocking' not only responses of the 180-188 specific arthritogenic T cell A2b, but also responses of the MBP specific encephalitogenic T cell Z1a, in vivo testing of this competitor peptide revealed a very prominent disease inhibitory activity in AA but not in MBP-induced EAE. The selectivity of this peptide in suppressing the disease in which native 180-188 appears to be of critical relevance, offers the possibility of achieving disease specific immunological intervention. Based on the results collected so far, it seems that, in vivo in addition to blocking activity, a variant peptide itself could trigger responses that confer protective activity in AA. Such combined activities may well be required for achieving full in vivo inhibition of a disease in which multiple distinct epitopes may play a role, possibly through presentation by more than one MHC product.

Animals↗
PubMed1992

Adjuvant arthritis and immunity to the mycobacterial 65 kDa heat shock protein.

The mycobacterial 65 kDa heat shock protein (HSP65) is of critical significance in the model of adjuvant arthritis (AA). Arthritogenic and protective T cell clones obtained from arthritic rats recognized the 180-188 sequence of HSP65. Previous reports have shown that administration of HSP65 prior to disease induction led to resistance to arthritis in the AA model and in several other models of experimental arthritis. Here, we report the development of immunity to HSP65 and the critical 180-188 epitope during the course of AA. Following Mycobacterium tuberculosis (MT) immunization both antibodies and T cell responses to HSP65 were detected. Proliferative responses to the 180-188 epitope were seen exclusively in the local draining lymph node cells at day 14 after immunization. The anatomical distribution and course of T cell responses to HSP65 and its 180-188 epitope are compatible with T cell regulated control of the disease. Although lower HSP65 antibody levels were observed in the animals with severe arthritis, in individual animals no evidence was obtained for a relationship between development of HSP65 humoral immunity and arthritis severity. Nevertheless, during disease exacerbation, elicited by HSP65 immunization during disease development, elevated T cell responses against HSP65 and its 180-188 epitope were found. In contrast, we obtained evidence that successful transfer of arthritis resistance to naive recipients depends on the transfer of HSP65 specific T cells. On the basis of these results, it seems that HSP65 plays a crucial role in the T cell regulatory events involved in both the induction of, and protection against, AA.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Stimulation of synovial fluid mononuclear cells with the human 65-kD heat shock protein or with live enterobacteria leads to preferential expansion of TCR-gamma delta+ lymphocytes.

T lymphocyte responses to heterologous or self 65-kD heat shock protein (hsp) have been implicated in the pathogenesis of various forms of arthritis. To delineate the relationship of 65-kD hsp to different synovial fluid (SF) T cell subsets, we stimulated synovial fluid (SFMC) and peripheral blood mononuclear cells (PBMC) from patients with different inflammatory rheumatic diseases and from healthy controls with human or mycobacterial 65-kD hsp, tetanus toxoid (TT), heat-killed or live Yersinia enterocolitica. Phenotyping of the resulting T cell lines revealed an increase of up to 97% TCR-gamma delta+ lymphocytes in the 65-kD hsp-stimulated SF-derived lines. This expansion of TCR-gamma delta+ cells was less pronounced with cultures of PBMC. A preferential expansion of TCR-gamma delta+ cells was also shown after SFMC stimulation with live, but not with heat-killed Yersinia or with TT. We conclude that a common mechanism is involved in the selective expansion of TCR-gamma delta+ lymphocytes upon SFMC infection with live Yersinia or upon contact with 65-kD hsp. Out of a panel of TCR-gamma delta+ T lymphocyte clones (TLC) derived from a human 65-kD hsp-stimulated line, only a minority of TLC proliferated weakly upon restimulation with this antigen in the presence of autologous monocytes, whereas TCR-alpha beta+ TLC responded vigorously to the human 65-kD hsp and in some cases also cross-recognized the mycobacterial hsp homologue and/or heat-killed Yersinia. This implies that additional factors or cells may be present in the milieu of SFMC cultures that propagate the expansion of TCR-gamma delta+ cells in response to 65-kD hsp or live bacteria.

Cell Line↗
PubMed1992

Antigen-activated T cells inhibit cartilage proteoglycan synthesis independently of T-cell proliferation.

Previously we have shown that blood mononuclear cells (MNC) obtained from patients with rheumatoid arthritis (RA) have the capacity to induce depletion of proteoglycans (PG) in human cartilage explants. This was observed especially after stimulating MNC with mycobacterial antigens, rather than with the mitogen Concanavalin A (Con A). We have now co-cultured cartilage explants in the presence of T-cell clone A2b obtained from the rat model of adjuvant arthritis (AA). We show that inhibition of the cartilage PG synthesis is a consequence of antigen-specific T-cell activation and that it is mediated by a humoral factor. This seems to be a cytokine rather than an enzyme. Moreover, at the level of polyclonally responding T cells, inhibition of PG synthesis due to T-cell activation by mycobacterial antigens was shown to depend on prior mycobacterial immunization. Arthritogenic T-cell clone A2b also showed PG synthesis inhibitory effects when co-cultured with cartilage alone. The inhibitory activity was shown to be unrelated to the degree of T-cell proliferation. We conclude that antigen-specific T-cell activation may be one of the initiating events leading to cartilage damage in arthritic processes. The measurement of T-cell-mediated PG synthesis inhibition may be a more sensitive and relevant assay for the detection of pathogenic T cells than T-cell proliferation.

Animals↗
PubMed1991

A systematic molecular analysis of the T cell-stimulating antigens from Mycobacterium leprae with T cell clones of leprosy patients. Identification of a novel M. leprae HSP 70 fragment by M. leprae-specific T cells.

Both protective immunity and immunopathology induced by mycobacteria are dependent on Ag-specific, CD4+ MHC class II-restricted T lymphocytes. The identification of Ag recognized by T cells is fundamental to the understanding of protective and pathologic immunity as well as to the design of effective immunoprophylaxis and immunotherapy strategies. Although some T cell clones are known to respond to recombinant mycobacterial heat shock proteins (hsp) like hsp3 65, the specificity of most T cells has remained unknown. We therefore have undertaken a specificity analysis of 48 well defined Mycobacterium leprae- and/or Mycobacterium tuberculosis-reactive (Th-1-like) T cell clones. Most clones (n = 44) were derived from different leprosy patients, and the remainder from one healthy control. Their HLA restriction molecules were DR2, DR3, DR4, DR5, DR7, DQ, or DP. T cell clones were stimulated with large numbers (n = 20 to 40) of mycobacterial SDS-PAGE-separated fractions bound to nitrocellulose. Each clone recognized a single fraction or peak with a particular Mr range. Some of the clones (n = 7) recognized the fraction that contained the hsp 65 as confirmed with the recombinant Ag. Most clones (n = 41), however, responded to Ag other than the hsp 65. Nine clones responded to a 67- to 80-kDa fraction. Five of them responded also to an ATP-purified, 70-kDa M. leprae protein, but only one of these five (that was HLA-DR2 restricted and cross-reactive with M. tuberculosis) recognized the recombinant C-terminal half (amino acids 278-621) of the M. leprae hsp 70 molecule and also recognized the recombinant M. tuberculosis hsp 70. We therefore have used the 5' part of the M. leprae hsp 70 gene that we have cloned recently. This fragment (that encodes amino acids 6-279) was indeed recognized by the other four M. leprae-specific T cells that were all HLA-DR3 restricted and did not cross-react with the highly homologous (95%) M. tuberculosis hsp 70. These results suggest that this novel fragment is a relevant T cell-stimulating Ag for leprosy patients. A panel of other recombinant Ag, including hsp 18 was tested. The majority of T cell clones appeared to recognize antigenic fractions distinct from hsp. In conclusion, T cells of leprosy patients see a large variety of different Ag including non-hsp, and one newly recognized moiety is the N-terminal M. leprae hsp 70 fragment.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenosine Triphosphate↗
PubMed1991

Recognition of human 60 kD heat shock protein by mononuclear cells from patients with juvenile chronic arthritis.

A postulated mechanism for autoimmune disorders is that the immunoreactivity develops against bacterial antigens which show a high degree of sequence homology with mammalian proteins. The mycobacterial 65 kD heat shock protein (hsp) has been implicated in several forms of arthritis. Substantial amounts of the human 60 kD homologue (hsp60) were produced by insertion of the gene into Escherichia coli. To investigate the hypothesis that T-cell reactivity is directed against the endogenous hsp, T-cell proliferation of synovial-fluid and peripheral-blood mononuclear cells in response to hsp60 was studied in samples from six patients with juvenile chronic arthritis (JCA) and nine adult patients with rheumatoid arthritis (RA). There was no T-lymphocyte proliferative response to purified fractions of hsp60 in mononuclear cells from RA patients or healthy children and young adults. However, both synovial-fluid and peripheral-blood mononuclear cells from JCA patients showed substantial proliferative responses. There was a significant correlation between the stimulation indices for human hsp60 and for mycobacterial hsp65 (r = 0.948, p less than 0.02). A similar correlation for hsp60 and mycobacterial hsp70 did not achieve significance. Immunohistochemistry showed that hsp65 and hsp70 homologues were expressed in the synovial membrane in these patients but not in controls. These findings suggest a sequence of events in which hsps become expressed during synovial inflammation and function as autoantigens. In JCA this may be manifested by specific T-cell reactivity which apparently is lost in the more bone-eroding and non-remitting adult disease.

Adolescent↗
PubMed1991

Vaccination against autoimmune mouse diabetes with a T-cell epitope of the human 65-kDa heat shock protein.

Insulin-dependent diabetes mellitus is caused by autoimmune destruction of the insulin-producing beta cells resident in the pancreatic islets. We recently discovered that the pathogenesis of diabetes in NOD strain mice was associated with T-cell reactivity to an antigen cross-reactive with a mycobacterial 65-kDa heat shock protein. To identify peptide epitopes critical to the insulin-dependent diabetes mellitus of NOD mice, we studied the specificities of helper T-cell clones capable of causing hyperglycemia and diabetes. We now report the identification of a functionally important peptide within the sequence of the human variant of the 65-kDa heat shock protein molecule. T-cell clones recognizing this peptide mediate insulitis and hyperglycemia. Alternatively, the T cells can be attenuated and used as therapeutic T-cell vaccines to abort the diabetogenic process. Moreover, administration of the peptide itself to NOD mice can also down-regulate immunity to the 65-kDa heat shock protein and prevent the development of diabetes. Thus, T-cell vaccination and specific peptide therapy are feasible in spontaneous autoimmune diabetes.

Animals↗
PubMed1991

Natural antibodies to 65 kD mycobacterial heat shock protein in rats do not correlate with susceptibility for Mycobacterium tuberculosis induced adjuvant arthritis.

Natural antibodies to 65 kD heat shock protein (hsp65) of Mycobacterium bovis were found in the sera of Lewis rats. The levels of these natural hsp65 antibodies differed substantially between the individual rats. Each rat was subsequently tested for its susceptibility to develop arthritis following injection of M. tuberculosis in incomplete Freund adjuvant. It was found that the incidence and severity of the induced arthritis did not differ between groups of Lewis rats with relatively high and relatively low natural antibody levels to hsp65. Inoculation of rats without natural antibodies to hsp65 with intestinal contents did not induce hsp65 antibodies, although the rats were able to respond to the antigen.

Animals↗
PubMed1991

Epitope specificity and MHC restriction of rheumatoid arthritis synovial T cell clones which recognize a mycobacterial 65 kDa heat shock protein.

CD4+ T cell clones specific for the mycobacterial hsp 65 were obtained from synovial fluid of a DR4 homozygous rheumatoid arthritis (RA) patient. A stimulatory epitope was defined using both deletion mutants of the mycobacterial hsp 65 and synthetic peptides and proved to be in a highly conserved region of the molecule. Despite this, however, there was no recognition by these clones of either the recombinant human homologue of mycobacterial hsp 65, P60, nor of a synthetic peptide containing an amino acid sequence from P60 corresponding to the epitope defined in the mycobacterial hsp 65. When the pattern of HLA restriction shown by the hsp-65-specific T cell clones was investigated, all clones tested proved to be restricted by HLA-DP rather than the more usual HLA-DR. Inhibition experiments suggested that this restriction also applied to the polyclonal synovial T cell response to hsp 65, but not to other antigens. Exclusive restriction of T cell recognition of an antigen by HLA-DP has not been reported previously, and strongly suggests that in this case the T cell repertoire for recognizing hsp 65 in the context of DR4 is deficient. Such an association between DR4 and the inability to respond to an immunodominant bacterial antigen may have implications for the pathogenesis of RA.

Amino Acid Sequence↗
PubMed1991

Association between the 65-kilodalton heat shock protein, Streptococcus sanguis, and the corresponding antibodies in Behçet's syndrome.

The etiology of Behcet's syndrome (BS) is unknown, but a number of streptococcal species have been implicated. A hypothesis was postulated that a shared antigen, such as a stress protein, might account for some of these findings. Indeed, a rabbit antiserum against a 65-kDa heat shock protein of Mycobacterium tuberculosis revealed a corresponding 65-kDa band with all six Streptococcus sanguis strains examined and S. pyogenes but not with S. salivarius. By applying a panel of nine monoclonal antibodies to the mycobacterial 65-kDa heat shock protein, an approximately 65-kDa antigen was identified in the uncommon serotypes of S. sanguis ST3 and H.83 and one with a different Mr was identified in KTH-1 and S. pyogenes. Monoclonal antibodies Y1.2, C1.1, II H9, and ML30, which reacted with these streptococci, recognize residues 11 to 27, 88 to 123, 107 to 122, and 276 to 297 of the 65-kDa heat shock protein, respectively, suggesting that these residues are conserved among some uncommon serotypes of S. sanguis and S. pyogenes. Immunoblot analyses of sera from patients with BS for immunoglobulin A (IgA) and IgG antibodies revealed bands of 65 to 70 kDa with the mycobacterial heat shock protein, S. sanguis strains, and S. pyogenes, although these reactivities were also found to a lesser extent in controls. A 65- to 70-kDa band was found more frequently with S. sanguis KTH-2 or KTH-3 and IgA in serum from patients with BS than with serum from controls (P less than 0.02). Antibodies in serum were then studied by a radioimmunoassay, and in patients with BS this revealed significantly raised IgA antibodies to the recombinant 65-kDa mycobacterial heat shock protein and to soluble protein extracts of S. sanguis ST3, KTH-1, KTH-2, and KTH-3. Whereas significant anti-65-kDa heat shock protein and anti-S. sanguis ST3 antibodies were also found in sera from patients with rheumatoid arthritis and recurrent oral ulcers, the anti-S. sanguis KTH-1, KTH-2, and KTH-3 antibodies were confined to BS. The results are consistent with the hypothesis that some of the streptococcal antigens are associated with heat shock or stress proteins, which will need to be formally established by isolating heat shock proteins from streptococci.

Amino Acid Sequence↗