摘要:

A human-mouse hybridoma has been produced by fusion of Hashimoto thyroid lymphocytes with the mouse myeloma line X63-Ag8.653. The cloned hybridoma secreted 2.5µg per 106cells per day of an IgG kappa thyroid peroxidase (TPO) autoantibody (2G4) with high affinity (2.5×109molar−1) and specificity for human TPO. 2G4 did not react with lactoperoxidase, horseradish peroxidase or human myeloperoxidase or with porcine TPO or with human thyroglobulin. Plastic tubes coated with 2G4 bound about 50% of125I-labelled human TPO added and the binding was inhibited by IgGs prepared from 18/18 TPO autoantibody-positive sera. This indicated that all 18 sera contained autoantibodies which recognised the same (or closely related) epitope as 2′34. Plastic tubes coated with IgGs from different TPO autoantibody-positive patient sera also bound125I-labelled TPO but inhibition by 2G4 in this system was not complete. This suggested that the sera contained at least 2 types of TPO autoantibodies. with only one type of autoantibody reactive with the same epitope as 2G4.

ISSN:0891-6934    

DOI:10.3109/08916939309077350

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor

摘要:

To investigate the prevalence of antibody against rat eye muscle membrane antigen, as determined from SDS-polyacrylamide gel electrophoresis and western blotting, in sera from patients with thyroid-associated ophthalmopathy (TAO). we quantitatively analyzed the binding activity with a rat eye muscle membrane 64 kDa protein using chromato-scanner. Eye muscle antibody activity was expressed as ratio of density of the 64 kDa band to that at 66 kDa found with all normal sera and phosphate buffered saline. The mean (±SD) eye muscle antibody activity was 2.7±2.7 in TAO (P<0.01 V.S. normal). 1.5±1.7 in Graves' disease without evident eye disease. 1.6±2.5 in Hashimoto's thyroiditis and 0.45±0.26 in normal subjects. A positive band at 64 kDa was found in 71 % of patients with TAO. 36% of those of Graves' disease without evident eye disease and in 35% of patients with Hashimoto's thyroiditis without eye disease. The prevalence of this antibody activity tended to correlate to the severity of ophthalmopathy. Furthermore. the level of eye muscle antibody activity decreased in parallel with the improvement of eye signs in two patients. Sera reactive with rat eye muscle membrane 64 kDa protein reacted also with a human eye muscle membrane 64 kDa protein but not with human thyroid, liver, spleen or pancreas membrane preparations. In conclusion, antibody to rat eye muscle membrane 64 kDa protein is present in TAO and may be a useful clinical marker of ophthalmopathy.

ISSN:0891-6934    

DOI:10.3109/08916939309077351

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor

摘要:

The accumulation of desialylated radiolabelled normal spleen cells and non-neuroantigen specific CD4 T-lymphocytes was measured in the lumbosacral spinal cord of Lewis rats with autoimmune encephalomyelitis (EAE) induced with myelin basic protein in Freund's adjuvant. The labelled cells were preincubated with sialidase and thoroughly washed prior to intravenous injection into rats exhibiting early clinical signs of EAE. Four hours later, the rats were killed and blood and spinal cord samples were radioassayed. Compared with untreated cells, desialylation markedly reduced the accumulation of both normal spleen cells and memory T-lymphocytes in the spinal cord, despite similar levels of cells being present in the blood. In another experiment, the accumulation of desialylated, macrophage-depleted spleen lymphocytes was measured during the onset, recovery and short-term“relapse”phases of acute EAE. Again, compared with controls the accumulation of desialylated lymphocytes was always significantly less, despite similar numbers of cells in the circulation. Lastly, intravenous injections of sialidase produced delayed onset of both clinical and histological signs in rats with passively-transferred EAE. These data confirm and extend previous findings, using a different animal model, that sialyl residues on the lymphocyte surface are important to the accumulation of such cells at inflammatory sites in the central nervous system. The possible relevance of these findings to human demyelinating disease is discussed.

ISSN:0891-6934    

DOI:10.3109/08916939309077352

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor

摘要:

Microbial superantigens (SA) activate a significant portion of the T cell repertoire based on their dual avidity for MHC class II antigens and T cell receptor (TCR) epitopes common to products of one or several TCRβchain variable gene families. While SA that induce massive T cell proliferation and cytokine secretion have been implicated in clinical syndromes characterized by shock and generalized immunosuppression, SA activation of a more restricted T cell response may also have significant, perhaps immunostimulatory, effects on the immune system. To investigate this issue, we measured3H-thymidine incorporation and polyclonal IgM and IgG secretion by normal human peripheral blood mononuclear cells (PBMC) cultured with a panel of microbial SA, including theStaphylococcus aureus-derivedSA. SEA, SEB, SEC-1, SEC-2. SEC-3, SEE, TSST-1, and theMycoplasma arthritidis-derivedSA. MAM. The S.aureus-derivedSA induce vigorous proliferation by PBMC. while optimal MAM-induced proliferation is significantly lower in magnitude. In all 12 subjects tested, mitogenic concentrations of MAM reproducibly stimulate unselected PBMC to secrete polyclonal IgM and IgG. In contrast, theS. aureus-derivedSA induce Ig production only in cultures containing isolated B cell populations and either very low numbers of untreated autologous T cells, larger numbers of X-irradiated autologous T cells, or very low concentrations of the SA. No difference in the activation of helper (CD4) versus suppressor/cytotoxic (CD8) T cells by MAM and the S.aureus-derived SA was noted. Taken together, these data suggest that MAM's capacity to induce B cell differentiation correlates with its induction of a relatively weak proliferative response by unselected human T cells. MAM-like SA. when encounteredin vivo, may result in a significant perturbation of the human immune system and potentially contribute to clinical syndromes characterized by immunostimulation and hypergammaglobulinemia.

ISSN:0891-6934    

DOI:10.3109/08916939309077353

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor

摘要:

A high prevalence of antibodies to double-stranded DNA (AbDNAds) has been recently reported in serum of patients with autoimmune thyroid disorders, but the specificity of this finding has been questioned. For this reason, the prevalence of several antibodies to DNA-related nuclear antigens (AbDRENA) has been evaluated in sera of patients with autoimmune and non-autoimmune thyroid disease. The study group included: 46 Graves’disease patients, 28 Hashimoto's thyroiditis patients, 25 patients with toxic nodular goitre and 11 with non-toxic nodular goitre. Twenty-eight Graves' patients were retested during methimazole (MMI) therapy, and 5 after radioiodine administration. Twenty-two patients with systemic lupus erythematosus and 28 normal subjects served as positive and negative controls, respectively. AbDRENA included: AbDNAds by RIA or immunofluorescence (IF); antibodies to single-stranded DNA (AbDNAss) and antibodies to histone (AbHist) by ELISA methods; antibodies to nuclear antigens (ANA) by immunofluorescence. RIA values were considered to be abnormal when 2 SD above the mean of normal controls. In our study 13% of Graves' patients were positive for AbDNAds by RIA: all of them had negative tests by IF; 11% were positive for AbDNAss. 2% for AbHist and 7% for ANA. A comparable prevalence of positive results for AbDNAds by RIA. with negative IF tests, was found in Hashimoto's thyroiditis patients. No significant changes of antibody levels were observed in Graves' patients during MMI treatment or after radioiodine administration. A positivity for AbDNAds or AbDNAss was found in 8% of patients with toxic nodular goitre, but in none of those with non-toxic goitre. All patients with systemic lupus erythematosus had positive tests for AbDNAds by both RIA and IF.In conclusion, the results of the present study indicate that: (i) the prevalence of anti-DNA antibodies is low and does not differ in the different groups of thyroid patients, irrespective of the presence of thyroid auto-immunity and/or thyroid hyperfunction; and (ii) different techniques (e.g. RIA vs. IF) may provide discrepant results, thus at least partially explaining differences among various series.

ISSN:0891-6934    

DOI:10.3109/08916939309077354

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor

摘要:

1,25-dihydroxyvitamin D3(1,25–(OH)2D3), the biologically active form of vitamin D3, has been shown to modulate lymphocyte functionsin vitro. These effects are exerted through binding to specific receptors that are expressed in activated, but not in resting lymphocytes. 1.25–(OH)2D3inhibits lymphocyte proliferation, immunoglobulin production and the release of cytokines including interleukin-2 (IL-2) and interferonγ(IFNγ) by mitogen driven blood mononuclear cells (MNC). A distinction between CD45RA+ and CD45R0+ subsets of T cells has, however, proven extremely relevant in terms of immunoactivation and immunopathology. The present study was undertaken to evaluate effects of 1,25–(OH)2D3on proliferation and cytokine production by purified CD45RA+ and CD45R0+ T cells.1,25–(OH)2D3caused a dose- and time-dependent reduction in phytohemaglutinin-(PHA) and poke-weed mitogen (PWM)-driven proliferation of purified CD45R0+ T cells. In contrast, proliferation of the CD45RA+ subset was unaffected by this treatment. Comparable levels of lymphotoxin (LT), IFNγand IL-2 were obtained in cultures of both subsets. 1,25–(OH)2D3reduced these levels, but the suppressive effect of the hormone was delayed in cultures of CD45RA+ T cells. The results suggest that the CD45RO+ subset is relatively more sensitive than CD45RA+ subset to the inhibitory effects of 1,25–(OH)2D3. This finding may be of pharmacological interest, because the CD45R0+ subset plays a key role in immune activation and because these cells have been associated with the pathogenesis of autoimmune diseases such as rheumatoid arthritis and multiple sclerosis.

ISSN:0891-6934    

DOI:10.3109/08916939309077355

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor

摘要:

We have tested the hypothesis that some phenotypic characteristics of the lymphocytes from mice with lymphoproliferative disease (Ipr) could be explained by abnormal glycosylation of membrane proteins. Lymph node cells from normal C57 BL/6 and from C57 BL/lpr mice were labelled with tritiated sugars. Membrane proteins were released with trypsin. then with pronase. After complete pronase digestion, glycopeptides were first separated on Bio Gel P-6 and then on Con A-Sepharose. Fractions not binding to Con A (Con A negative) were also separated onLens culinarisagglutinin-Sepharose. Marked differences between normal and Ipr cells were noticed. First, there were more glucosamine-labelled peptides with very high molecular weight (eluting fast on Bio Gel P-6) on Ipr cells than on normal lymphocytes. Second, the proportion of mannose-labelled peptides binding to Con A was smaller in the Ipr cells. Third, among the Con A negative peptides. the proponion binding toLens culinarisagglutinin was higher in Ipr cells. Thus, Ipr cells seem to carry moreα1–6 fucosylated chains and larger size carbohydrates. These alterations were also confirmed by gel electrophoresis of lectin-selected iodinated cell surface antigens and seem to be restricted to a very limited number of peptides. Thus, there may be primary changes in glycosylation in Ipr cells. Alternatively, the glycosylation pattern of Ipr cells may be characteristic for a subpopulation of T-lymphocytes that is expanded in this disease, or for a certain stage of activation. A large proportion of Con A-negative,Lens culinaris-positive peptides is a rather unusual feature in murine cells and requires further investigation.

ISSN:0891-6934    

DOI:10.3109/08916939309077356

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor

摘要:

Recent studies have shown that Ro/SSA autoantigen is heterogeneous and the autoanti-Ro/SSA response is correspondingly heterogeneous. There are two isoform families; the 60 kD forms and the 52 kD forms.We studied the antigenic difference between the native and denatured Ro/SSA isoforms and found that the autoanti-Ro/SSA response to the native 60 kD antigen is quite homogeneous. All anti-Ro/SSA sera recognize the native kD antigen regardless of the reactivities to the 60 kD band on the Western blot. Surprisingly, no anti-Ro/SSA sera without anti-La/SSB reacts with the native 52 kD Ro/SSA, although sera with both precipitating anti-Ro/SSA and anti-La/SSB can immunoprecipitate the native 52 kD antigen.Anti-Ro/SSA sera exist which react exclusively with the native 60 kD Ro/SSA protein (10/43. 232) while no anti-Ro/SSA sera have been found which react exclusively with the denatured 52 kD Ro/SSA antigen. In sera with anti-Ro/SSA precipitins alone, only antibody to the denatured 52 kD Ro/SSA molecule is found! In sera with anti-Ro/SSA and anti-U1RNP precipitins, no antibody to either native or denatured 52 kD Ro/SSA is found, while in sera with both anti-Ro/SSA and anti-La/SSB precipitins. antibodies to both the native and denatured forms of 52 kD Ro/SSA are present.These data suggest that the anti-Ro/SSA response to the 60 kD molecule is driven by the native 60 kD Ro/SSA molecule while the molecular identification of the antigen drive in the anti-52 kD Ro/SSA response is unknown.

ISSN:0891-6934    

DOI:10.3109/08916939309077357

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor

摘要:

Small stature is associated with low growth hormone secretion, but in most cases the reason is unknown. The commonest cause of hormone insufficiency is autoimmunity. and autoantibodies to hormones are often found where there is autoimmune disease of the corresponding gland.Displaceable growth hormone binding by the sera of 125 short (<3rd centile) but otherwise normal school entrants was significantly higher (P<0.05) than by the sera of 100 age-matched children of normal height (10th-90th centile), and binding in 21 (17%) of the small children exceeded the upper limit of 95% of the normal population. Furthermore, urinary growth hormone excretion was significantly lower in the small children (total overnight output 0.6–1.7 ng) compared with controls (1.5–3.7 ng) (P<0.05) even when corrected for body surface area. Thus, growth hormone binding and growth hormone excretion discriminated between two groups of children selected only on the basis of height. The assay used for growth hormone binding was specific for IgG. suggesting that the binding factor was antibody. Autoimmunity merits further investigation as a basis for poor growth.

ISSN:0891-6934    

DOI:10.3109/08916939309077358

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor

摘要:

The effects of preimmunisation with the 65 kD mycobacterial heat shock protein (hsp65) on 2 murine models of autoimmunity were compared. Experimental autoimmune haemolytic anaemia (AIHA) can be provoked in mice by repeated injection with rat red blood cells (RBC). In this model, preimmunisation with hsp65 10 days before induction of disease resulted in a partial. but significant, reduction in RBC-bound autoantibody levels measured by Coombs' test. However, preimmunisation with human IgG (hIgG) was associated with a similar suppressive effect. Administration of neither hsp65 nor hIgG affected the direct or indirect anti-rat agglutinin titres of mice subsequently injected with rat RBC. Injection of hsp65 or hIgG prior to induction of AIHA elicited the production of IgG antibodies against the respective immunogen, as judged by enzyme-linked immunosorbent assays. In contrast to the results in experimental AIHA, pristane-induced arthritis (PIA) was effectively prevented by preimmunisation with hsp65, but not with hIgG. It is considered that, whilst hsp65 injection may slightly reduce subsequent anti-RBC autoantibody production in AIHA by antigenic competition, such a mechanism cannot account for the substantial protection against PIA afforded by hsp65 preimmunisation. We suggest that the high, sustained production of anti-hsp65 antibodies observed in mice given hsp65 and pristane may play a role in specifically suppressing mhritogenic immune responses in PIA.

ISSN:0891-6934    

DOI:10.3109/08916939309077359

出版商:Taylor&Francis    

年代:1993

数据来源: Taylor