Circulating monoclonal IgM lambda cryoglobulin with collagen type I affinity in vasculitis.

A previously fit 66-years-old male primarily presented symptoms compatible with Henock-Schönlein's purpura, from which he seemingly recovered. Shortly hereafter he relapsed with an IgM lambda essential monoclonal cryoglobulinemia type I, presenting a systemic, necrotizing vasculitis, with low titer of circulating immune complexes and complement consumption. Glucocorticoid treatment and plasmapheresis did not prevent an ultimately lethal course. An indirect immunoperoxidase technique showed that the cryo-IgM bound to the interstitial connective tissue corresponding to the localization of collagen type I. In addition it bound to affinity purified human procollagen type I. These results indicate, that the IgM lambda of the proband was an autoantibody with collagen type I specificity.

Immune-induced vascular connective tissue alterations in rabbits chronically immunized with bovine serum albumin: biochemical studies on collagen, glycosaminoglycans, RNA, and DNA in normal and injured aorta.

Repeated intravenous injections of bovine serum albumin in rabbits caused a significant reduction in the aortic in vivo biosynthesis of chondroitin-4,6-sulfate, whereas no changes were observed in the synthesis of other glycosaminoglycans nor in the content of collagen. This contrasts the biochemical changes generally seen in acute vascular injury. When experimentally elicited vascular injury and repair processes were induced in chronically immunized rabbits, the proliferative response was greatly inhibited, as reflected by a significant diminution of the DNA amount. Also, the vascular connective tissue matrix repair was restrained: the aortic content of collagen and the collagen type III/I ratio was repressed, and the in vivo biosynthesis of sulfated glycosaminoglycans was markedly reduced. All immunized rabbits developed antibodies to bovine albumin, but in only a few were circulating immune complexes detected. The inhibitory effect of persistent immunostimulation on the nonspecific processes of repair in vascular connective tissue may be of significance as to chronicity of vasculitis, as well as inflammation and repair in general, in inflammatory connective tissue diseases.

Late-onset rubella syndrome: coexistence of immune complex disease and defective cytotoxic effector cell function.

We studied a classical case of late-onset rubella syndrome characterized by multi-organ disease and persistence of live rubella virus in spite of high titres of specific antirubella antibodies and presence of large amounts of circulating immune complexes. When first studied at the age of 5 months there was a low proportion of T8+ lymphocytes. Functional studies revealed decreased activity of K and NK cells as well as alloreactive direct cytotoxic cells (CTL). Removal of cell-bound immunoglobulin and immune complexes tended to improve K and NK cell function in vitro. Plasma exchange transfusions carried out at 9 months of age resulted in clinical improvement. Normalization of cytotoxic effector cell functions and cessation of viremia accompanied recovery from active disease. The results indicate that defective cytotoxic effector cell function is the primary cause for the defective virus elimination in this syndrome.

Oral administration of grass pollen to hay fever patients. An efficacy study in oral hyposensitization.

Oral hyposensitization is still widely used in the treatment of allergic diseases, but controlled studies proving a beneficial effect are lacking. Fifty-eight hay fever patients were admitted to a double-blind placebo efficacy study in oral hyposensitization. An enterosoluble tablet containing timothy whole pollen or placebo was taken daily. Preseasonally, the actively treated patients received 4,315,000 PNU (880,260 AUR) and totally for 6 months 8,915,000 PNU (1,818,660 AUR). Such high doses have never been tried in similar studies. A new principle has been used - "the pollen count interval method" - in the evaluation of symptom and medication score. The study failed to prove any beneficial effect of oral hyposensitization measured by symptom score, medication score, nasal provocation test or skin prick test. There was no change in timothy specific IgE and IgG which could be caused by the treatment. The possibility that oral hyposensitization might be an effective treatment of hay fever in the future is discussed, but it is concluded that the present regimens cannot be recommended.

Circulating immune complexes in myelofibrosis.

17 patients with idiopathic myelofibrosis were studied for the occurrence of circulating immune complexes (IC), using a polyethylene glycol complement consumption and a polyclonal rheumatoid factor inhibition assay. In 13 patients complement C3d was determined by rocket immunoelectrophoresis. Circulating IC were detected in 6 patients and were primarily found in patients with short duration of disease from time of diagnosis. The median duration of the disease in IC-positive patients was 4 months, compared to 12 months in the IC-negative group (P less than 0.05). 9 of the 13 patients investigated had increased levels of plasma C3d. However, there was no correlation to the occurrence of IC. It is concluded that circulating IC may take part in an immune-mediated bone marrow damage. This may involve deposition of IC in the bone marrow with secondary inflammation responsible for the development of bone marrow fibrosis.

Plasma separation in patients with bronchial asthma, atopic dermatitis and hyperimmunoglobulinaemia E.

The effect of intensive plasma separation performed eight times within 5 weeks in four patients with atopic dermatitis, bronchial asthma and hyperimmunoglobulinaemia E was followed as regards clinical symptoms and changes in the concentrations of serum (S) IgE, S IgG, S IgA, S IgM, plasma complement C3 split products, S transferrin, blood eosinophils, chemotaxis of neutrophil cells and histamine metabolites in urine in samples obtained consecutively during the period of observation. The occurrence of circulating immune complexes (IC) was analysed by a polyclonal rheumatoid factor (pRF) agglutination inhibition assay and an IgE IC specific technique. IgE IC were demonstrated in three of the patients prior to plasma separation, complexed IgE was 2-3% of the total concentration of S IgE. In one patient complexes were detected by the pRF agglutination inhibition assay, also. In the three patients with IgE IC, the complexes disappeared during treatment, but recurred in two of the patients shortly after the last plasma separation. Shortly after eight separations the S IgE was reduced in all patients to a mean level of 46% of the pre-exchange concentrations. During the following 3 weeks the relative increase of S IgE in three of the patients was similar to the values obtained for S IgG. Serum IgG was subnormal in all patients during the period of treatment. Increasing numbers of eosinophils were observed in three of the patients after the fifth separation procedure. The histamine metabolite 1,4-methylimidazoleacetic (1,4- MIAA ) in urine was increased in all patients, but no significant changes were observed during the treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Determination of IgE-containing immune complexes in human sera. Evaluation of polyethylene glycol precipitation of monomeric and complex IgE and of the detectability of IgE in the complexes.

We studied the polyethylene (PEG) precipitability of monomeric human IgE, and of human IgE artificially complexed with rabbit anti-human IgE. At conditions where precipitation of monomeric IgE did not occur, from 0.2 to 20% of the complexed IgE was precipitated. The PEG precipitability of the complexes was inversely related to the IgE/anti-IgE ratio used for preparation of the complexes. From 1.5 to 19.2% of the IgE in the redissolved precipitates could be detected by use of a two-site IgE immunoradiometric assay, the percentage being highest for complexes formed at equivalence. We conclude that exact quantitation of circulating IgE immune complexes (IC) probably is impossible by any PEG precipitation assay. However, the optimized assay was found to be useful for identification of IgE IC in sera with total IgE concentrations below 5,000 U/ml. IgE IC were found in 5/20 sera from patients with Felty's syndrome, in 5/39 sera from patients with extrinsic allergy and high levels of specific IgE, and in 1/17 sera from immunized wasp allergics. No IgE IC were found in 20 normal human sera.

Complement-mediated solubilization of immune complexes. Solubilization inhibition and complement factor levels in SLE patients.

Thirty-two of 36 serum samples from 19 SLE patients showed reduced capacity to mediate complement-dependent solubilization of immune complexes (IC). SLE patients with nephritis exerted the lowest complement-mediated solubilization capacity (CMSC) whereas sera from patients with inactive disease gave the highest CMSC values, with three out of four samples within the normal reference range. Thirty-five of the 36 serum samples showed inhibition of CMSC in a newly developed CMSC inhibition assay. The strongest CMSC inhibition was exerted by sera from newly discovered cases of SLE who received no medical treatment and the lowest inhibition by sera from patients with inactive disease. There was a significant negative correlation between CMSC and CMSC inhibition (r = -0.67, P less than 0.001). Sera with low concentrations of C1q, C3, factor B or high C3d levels showed markedly reduced CMSC values. Pronounced CMSC inhibition was observed only in samples with normal or high factor H values. No significant correlation was found between CMSC or CMSC inhibition and circulating IC levels, but pronounced CMSC inhibition was registered only in strongly IC positive sera.

Complement C3c and C3d in plasma and synovial fluid in rheumatoid arthritis.

By means of recently developed immunochemical assays increased levels of the complement C3c and C3d split products were found in synovial fluids of patients with rheumatoid arthritis (RA) as compared with synovial fluids of patients with traumatic synovitis (TS). In plasma, only the C3d levels were significantly increased compared with plasma levels of patients with TS. Both split products were higher in RA synovial fluids (SF) than in RA plasma. A positive correlation between the C3d concentrations in plasma and the presence of IC in serum was found, and between the C3c levels and the concentration of polymorphonuclear cells in SF of RA patients. Due to differences in turn-over of C3c and C3d determination of plasma C3d levels may be a useful parameter for the evaluation of immunological activity in RA, while measurement of C3c in the synovial fluid may elucidate the actual inflammatory activity in the synovial membranes.

Autoantibodies, immune complexes and HLA-D in thyrogastric autoimmunity.

Forty-one patients with Hashimoto's thyroiditis (HT) and 82 with Pernicious anaemia (PA) were investigated. All 123 patients were HLA-D typed and results correlated to thyroglobulin antibodies (TgAB), microsomal antibodies (MAb), parietal cell antibodies (PCA), circulating immune complexes (IC), and intrinsic factor antibodies (IFA). In PA, TgAb was found less frequently in Dw2 positive patients than in Dw2 negative patients. IFA was rarely found in Dw5 positive PA patients. In HT, patients positive for Dw5 had lower levels of TgAb. IC were present in 67% of patients with HT, but only in 2.5% of patients with PA (p less than 0.01). Dw5 was associated with low levels of IC in HT. In conclusion, HT and PA seem to be related by their association with HLA-D types, but a heterogeneity in the pattern of antibodies and IC could be seen. The organ specific antibodies characteristic for each disease were present in lower levels in patients with Dw5.

Circulating immune complexes in Hashimoto's thyroiditis. Correlation to HLA and autoantibodies.

Circulating immune complexes (IC) were determined in sera from 41 patients with Hashimoto's thyroiditis by a polyclonal rheumatoid factor (pRF) assay based on the inhibition of the agglutination of IgG-coated latex particles. Elevated levels of IC were found in 63% (26/41) of the sera. There was a significant correlation (Rho = 0.91, P less than 0.001) between results obtained before and after treatment of sera with dithiothreitol (DTT). By precipitation with 2.5% polyethylene glycol (PEG) before pRF inhibition assay, the activity of IC was found in only 7% (3/41) of the sera. Size chromatography studies of the sera showed the inhibitory activity predominantly in the intermediary region. When found in the IgM-region the activity was not reduced by DTT. By use of a polyethylene glycol complement consumption test (PEG-CC) the occurrence of IC was 10% (4/41). It was not possible to find any correlation between the detectable IC and the presence of microsomal, thyroglobulin, or thyroid-stimulating antibodies. Based on our studies the sizes of IC seemed to be heterogeneously distributed and the majority were not precipitated by PEG (2.5%), final concentration). The antibodies involved in the formation of complexes seemed to be of IgG or IgA classes. HLA-D typing of the patients showed a non-significant association between HLA-Dw5 and low levels of IC while the presence of HLA-Dw4 was significantly associated with a high level of IC (P less than 0.05).

Discrepancy between haemagglutination and radioimmunological techniques for measurement of serum thyroglobulin autoantibodies.

Recently, it has been suggested that in some patients with autoimmune thyroid diseases the tanned red cell (TRC) method for detection of thyroglobulin autoantibodies (TgAb) is negative where TgAb measured by radioimmunoassay (RIA) show positive values. To investigate this further, patients with thyroid diseases, pernicious anaemia and a control group were studied for serum concentrations of TgAb by TRC and by quantitative RIA, calibrated against MRC Standard A65/93. Antibodies for microsomes (MAb) were measured immunofluoretically. There was in all patient groups (Hashimoto's thyroiditis (n = 41), Graves' disease (n = 50), idiopathic myxoedema (n = 12), euthyroid Graves' disease (n = 7), pernicious anaemia (n = 81) a discrepancy between TgAb measured by TRC and RIA, respectively, whereas there was a reasonable correlation between the presence of TgAb by RIA and the presence of MAb. A possible interference from antinuclear antibodies and rheumatoid factors was ruled out. There was no increased frequency of TgAb measured by RIA in the control group. Fractionation of TRC negative sera revealed macromolecular TRC-activity, whereas TgAb positive sera by both methods had almost exclusively RIA and TRC activity corresponding to IgG. Based on these results and others it seems that the TRC method for measurement of serum TgAb is of limited diagnostic value. Furthermore, the TRC method is in many cases not sensitive enough for screening for TgAb prior to measurement of serum Tg, which is of importance as this method shows false values in the presence of TgAb due to methodological interference.

Studies on hypersensitivity to bacterial antigens in intrinsic asthma.

Twelve children, aged 4 to 14 years, with moderate to severe intrinsic asthma (IA) were studied. Symptom-Score charts were used to confirm the relationship of acute respiratory tract infections to exacerbations of asthma. Hypersensitivity to eight commonly occurring bacteria from the normal flora of the upper respiratory tract was studied by skin test, by crossed immunoelectrophoresis, and by basophil histamine release in vitro, using ultrasonicates of the bacteria as antigens. Skin tests were all negative. All children contained low titers of precipitating antibodies against most of the bacteria, but in this respect they did not differ from normal children. In contrast, release of histamine was induced in leukocytes from the IA children by all, or most sonicates, while such reactions, were less frequent in control children. The pattern of responses indicated an element of specificity. These was no correlation to precipitating antibodies, or to the microbial flora of the children. Positive responses were characterized by low values of maximal histamine release, and by a tendency to fluctuations with time. Because of these fluctuations, and because the IA children and control children were tested on separate occasions, we cannot be certain as to the real difference between these two groups. Our studies do, however, demonstrate that water-soluble constituents of all the bacterial strains tested were capable of causing the release of histamine in vitro, but that this phenomenon is not restricted to IA. The clinical significance of these findings awaits further investigations on the mechanism(s) of release in vitro by such agents.