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Structural and immunological properties were determined for sixteen IgG and one Bence-Jones, human monoclonal cryoglobulins. The heavy chain subclass percentages were 47% IgG,, 14% IgG2 and 29% IgG3, and were different from previously reported distributions of myeloma proteins. In addition, 69% (eleven out of fifteen) of the cryoglobulins and 100% (seven out of seven) of the IgG1, cryos contained type lambda light chains. Electrofocussing of the cryoproteins by analytical liquid gradient column showed the isoelectric points to be included in the range of pH 6.3-8.9. The pI of six light chains and five out of six heavy chains were at acidic and slightly basic pH, respectively. The pi of the intact cryoglobulins were thus close to those of their constituent heavy chains. Six out of seven of the heavy chains were subjected to automated Edman degradation and were classified as containing vH-i or vH-ii variable region subgroups on the basis of their blocked amino termini. One type lambda light chain was unusual in that it contained an amino terminal sequence initially described in an amyloid fibril protein and is the first instance in which light chains with this sequence have been isolated from IgG. The data support the notion that the cryoglobulins are IgGs with unique structural and immunological properties which separate them from non-cryoprecipitable IgGs. [ABSTRACT FROM AUTHOR]

The metabolism of a monoclonal IgG crynglobulin was studied in a patient with primary idiopathic cryoglobulinaemia under two different clinical conditions. Early in the illness, cryoprotein levels were diminished to 770 mg% by plasmapheresis and plasma disappearance assayed while serum levels of cryoprotein increased to 1100 mg%, i.e. the study was performed during a period of unstable cryoprotein synthesis. A second study was performed 1 year later when serum levels of cryoglobulin were stable at 1500 mg% which allowed a synthetic rate of 64 mg/kg of body weight per day to be computed. This was the upper limit of normal IgG synthesis. The final slopes of the plasma disappearance curves were nearly identical for both studies, indicating that the same fractional percentage of the cryoglobulin serum pool was degraded regardless of its serum level. Tl/2 of 15.5 and 17.0 days were obtained when plasma levels were unstable and stable, respectively. For comparative purposes, the plasma disappearance of pooled normal IgG, IgG3 myeloma proteins and a highly aggregated IgG3 myeloma were also studied when cryoprotein levels wore 1500 mg%. Normal IgG synthesis was suppressed and only 8.5 mg/kg body weight per day, but its plasma disappearance curve showed a final slope nearly identical to those for the cryoprotein, indicating that the ability to catabolize normal IgG was unimpaired. IgGg myelomas were cleared at their normal accelerated rate, while aggregated IgG3 was totally cleared from the circulation within 2 days, indicating that the patient was able to catabolize circulating immune complexes. As controls, the catabolism of cryoprotein was shown to be identical to that of pooled normal IgG in two volunteers. The data support the concept that the build up of circulating IgG cryoprotein in the patient studied was due to an increase in cryoprotein synthesis and not to a lack of ability to catabolize it. [ABSTRACT FROM AUTHOR]

The Kappa chain variable region subgroup restriction of immunoglobulin (Ig) from patients with acquired hypogammaglobulinaemia, agammaglobulinaemia and drug-induced immunosuppression has been studied. The percent of K chain-containing Ig which expresses the VKIIIb variable region sub-subgroup was determined with a previously characterized murine monoclonal anti-VKIIIb antibody. The VKIIIb sub-subgroup percent was increased in sera from patients with idiopathic hypogammaglobulinaemia, as well as patients who became hypogammaglobulinaemic following immunosuppression. The implications of the results to the regulation of the human immune and autoimmune response are discussed. [ABSTRACT FROM AUTHOR]

The serological relatedness of the idiotypic (ID) determinants of one type lambda light chain dimer and fifteen monoclonal IgG cryoglobulins were assayed. Rabbits were immunized with 9/15 IgG cryoglobulins, and twenty-three antisera were obtained and absorbed to render them specific for the ID determinant of the immunizing IgG cryoglobulin. By use of haemagglutination-inhibition, cross-reactivity was detected among five cryoglobulins. This was localized to the Fab region of the IgG, was not related to identity of the variable region subgroups of the heavy and light chains of the cross-reactive cryoglobulins, and was not detected in eighteen non-cryoprecipitable IgG myeloma proteins. The serological relatedness of the ID determinants suggests that a subset of IgG cryoglobulins may possibly have similar variable region structures and/or antigenic specificities. [ABSTRACT FROM AUTHOR]

Monoclonal human anti-IgG preparations purified from mixed IgM-IgG cryoglobulins were tested for their antigenic specificity by haemagglutination-inhibition assay. A panel of fourteen IgG preparations of the four gamma chain subclasses were prepared from myeloma sera and used as inhibitors of haemagglutination. Each of six IgM anti-globulins demonstrated different reactivity profiles with these IgG preparations. In addition, the fraction of the serum IgG which had bound to and cryoprecipitated with the IgM preparations, termed 'antigen-IgG', was purified and assayed for subclass content. The γ chain subclasses found in the 'antigen-IgG' fractions showed that each IgM cryoprecipitated an IgG from serum which had different quantities of the subclasses present. These 'autologous' reactivity patterns were in instances different from the specificities expected from the results obtained with the myeloma proteins. When all antigen-IgG pools were tested with each IgM, some antiglobulins showed stronger reactivity with isologous than with their own, antigen-IgG pools. The IgM anti-IgG preparations were also compared in reactivity with IgG and its subunits in order to localize the antigenic determinant(s) with which these autoantibodies react. Heavy chains showed far greater reactivity than Fc fragment for 5/6 IgM preparations. Light chains, F(ab')2, pFc' and Fab were non-reactive. A relationship between the length of papain digestion and Fc reactivity was demonstrated. Based on the data, possible locations for the antigenic determinant(s) were considered. [ABSTRACT FROM AUTHOR]

The persistence in the structure of IgM anti-IgGs obtained from the serum of a patient (Gil) with Felty's syndrome was studied. Co-isoelectric focusing experiments showed that intact IgM from early (1970) and late (1973) sera, and their heavy and light chains had identical isoelectric points (pI). Light chains from 1970, 1973, and 1974 IgM-Gil had identical amino terminal amino acid sequences and belonged to the v Kappa II light chain subgroup. Specificity studies of IgM-Gil isolated from serum obtained in 1970, 1972 and 1974 showed identical patterns of reactivity with IgG and IgG subunits of all gamma chain subclasses. Finally, by haemagglutination-inhibition, antisera specific for idiotypic determinants of IgM-Gil-1970 were shown to be shared by IgM from 1970, 1972 and 1974 sera. The data support the notion that autoantibody-producing cell clones persist unaltered during the course of an untreated autoimmune disease, in this instance for 4½ years. [ABSTRACT FROM AUTHOR]

The specificity and reactivity patterns of monoclonal IgG, IgA and IgM anti-IgU autoantibodies isolated from the serum of one patient (Gil) have been determined for IgGs of the four gamma chain subclasses. The haemagglutination produced by the interaction of the Gil anti-IgGs and anti-Rh IgG coated erythrocytes was inhibited by a panel of intact IgGs, their polypeptide chains, and enzymatic fragments which included purified heavy chain constant region domains. Intact IgG1, JgG2 and IgG4 produced the same patterns of reactivity with the Gil anti-IgGs. When partially reduced and alkylated IgG1 heavy chains and its tryptic digests were tested, these were much more reactive than Fc fragments isolated from JgG of the four subclasses which were weaker inhibitors, and gamma chain constant region domains which were totally non-reactive. In all instances and by use of two anti-Rh antisera, the specificity patterns obtained for the Gil anti-IgGs were identical. The data combined with previous knowledge of the identity of the Gil light chains suggests that the antibody combining sites of these molecules are very similar if not identical. [ABSTRACT FROM AUTHOR]

Human IgO, IgA and 1gM anti-IgG autoantibodies have been isolated from the serum of an individual with Felty's syndrome. These were initially noted as soluble circulating serum complexes by analytical ultracentrifugation. Isolation was accomplished by solid phase immunoadsorption and each of the three antibody populations obtained was shown to be of restricted heterogeneity by liquid and polyacrylamide gel electrofocussing methods. Type kappa light chains were obtained from each protein. Co-isoelectric focusing experiments of all possible pairs of these light chains showed them to have identical net charge characteristics. Heavy chains obtained from each protein were also monoclonal and of differing isoelectric point. The availability of this serum provides a human model with which to study the changes which may occur in autoantibodies during the autoimmune response. [ABSTRACT FROM AUTHOR]

Southern blot analysis with human T-cell receptor (TcR) beta-chain specific cDNA probes revealed two novel allelic forms of the TcR beta-2 gene locus. Three different genotypes were noted based on the presence of polymorphic KpnI restriction fragments: I, 5.7 kb fragment only; II, 3.9 kb and 1.8 kb fragments only; III, all three polymorphic fragments. This hybridization pattern suggested that the presence or absence of a polymorphic KpnI site within the 5.7 kb fragment defines the two different allelic forms of the TcR beta chain locus. By Southern blot analysis of genomic DNA from T-cell lines with deleted C-beta-1 regions and computer-assisted restriction site mapping of germline and cDNA sequences of the C-beta-2 locus, the polymorphic KpnI site was localized at 24 bp 5′ to the third exon of the C-beta-2 gene. It was determined that the polymorphic KpnI site and the earlier described polymorphic BgIII site located 5′ to the C-beta-2 gene are not co-inherited. No difference was noted in distribution of the KpnI genotypes and allelic frequencies between 26 normal individuals and 22 patients with systemic lupus erythematosus. However, this newly characterized polymorphism of the TcR locus should provide a useful tool to analyse the role of inherited genetic variations in the function of T lymphocytes under normal and pathological conditions. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated that the IgM monoclonal anti-IgG autoantibodies (AGAs) characteristic of essential mixed cryoglobulinaemia (EMC) display preferential use of κ light chains of the Vkiiib sub-subgroup. In order to gain insights as to the possible basis for this V region selection, IgM-Vkiiib immunoglobulin was affinity purified from normal human serum, analysed by dissociating two-dimensional gel electrophoresis and compared to the two-dimensional gel patterns of IgM-Vkiiib anti-IgG autoantibodies (AGAs) from patients with essential mixed cryoglobulinaemia (EMC). The results suggest that only part of the available Vkiiib light chain repertoire is selected by EMC AGAs. When AGAs from EMC, rheumatoid arthritis (RA) and primary Sjögren's syndrome (SS) patients were analysed by ELISA, it was found that the association of Vkiiib light chains with anti-IgG autoantibodies differed significantly among the three diseases. In fact, in RA there appeared to be a negative selection against the use of Vkiiib in AGAs. Clearly, the Vkiiib determinant is not required for anti-IgG autoreactivity. The possibility emerges, therefore, that the genesis and perpetuation of AGA synthesis in these diseases may follow quite different pathways. [ABSTRACT FROM AUTHOR]

The VkIIIb sub-subgroup of the human immunoglobulin VkIIIb light chain subgroup has at least two unique properties. First, some IgM monoclonal autoantibodies, in particular cryoprecipitable anti- IgG (Kunkel et at, 1974; Ledford et at, 1983), anti-low density lipoprotein (Ledford et at, 1983) and certain cold agglutinin (Feizi et al., 1976) antibodies predominantly contain VkIIIb light chains. Second, in normal adult human serum, VkIIIb comprises approximately 25% of the IgM but less than 0-4% of the IgG or IgA kappa-chain pools (Moynihan, Looney & Abraham, 1985). Studies have suggested an altered regulation of IgM, IgG, and IgA-VkIIIb in some patients with acquired hypogammaglobulinaemia, a heterogeneous group of immunodeficiencies with low serum levels of Ig. An increase in the serum levels of VkIIIb light chains has been noted in some of these patients (Solomon & Mclaughlin, 1969) which is apparently due to elevated levels of light chains of the VkIIIb sub-subgroup (Greenstein & Abraham, 1984). However, the isotype association of VkIIIb in these patients has not been determined. In order to clarify whether the noted increase in VkIIIb levels is due to its selective expression with IgM or to an abnormality of immunoregulation, the heavy chain isotypes associated with VkIIIb light chains have been determined in a previously studied group of adults with acquired hypogammaglobulinaemia (Greenstein & Abraham, 1984). Further, the isotype distribution of VkIIIb light chains in another group of functional, albeit transient, hypogammaglobu-linaemics (i.e. normal neonates) has also been studied by measuring IgM-VkIIIb levels in cord blood, and compared to the VkIIIb serum levels found in aged adults (mean age 75 years). [ABSTRACT FROM AUTHOR]

The VKIII human kappa light chain sub-group has been serologically and structurally divided into two sub-subgroups, VKIIIa and VKIIIb. VKIIIb has been shown by others to be strikingly prevalent in IgM autoantibodies, but no studies have been per- formed to determine heavy chain isotype association with VKIIIb light chain in normal human serum. The VKIIIb sub-subgroup was shown here to be associated with mu heavy chain in normal human serum, but was not detected in association with gamma or alpha heavy chain. Approximately 25 ± 15% of IgM-kappa was determined to be VKIIIb. Both intact IgG and purified light chains from pooled IgG did not bind monoclonal anti-VKIIIb, indicating that the determinants recognized by anti-VKIIIb are not merely masked in intact IgG. These results are the first report of a light chain sub-subgroup showing preferential association with a heavy chain isotype. [ABSTRACT FROM AUTHOR]

Monoclonal antibody JG-B1, specific for the human VκIIIb sub-subgroup of L chains, and JG-B4 specific for an idiotypic determinant on Glo, a monoclonal human IgM-VκIIIb anti-IgG, were produced and characterized. The VκIIIb determinant was detected on L chains alone and intact immunoglobulins with VκIIIb L chains. However, the idiotypic determinant was expressed only on IgM-Glo and required association of H and L chains. Binding of the immunogen Glo, to its antigen-IgG partially inhibited anti-idiotype and anti-VκIIIb binding. Cross-inhibition experiments demonstrated that intact pentameric IgM-Glo expressed one-half the number of idiotypic sites as VκIIIb determinants. However, Glo half-molecules expressed equal numbers of idiotypic and VκIIIb determinants. This is the first described monoclonal antibody produced by hybridoma technology which recognizes an antigenic determinant specific for a single variable region in intact immunoglobulin. [ABSTRACT FROM AUTHOR]

The co-isoelectric focusing characteristics of the antigen-IgG and residual IgG pools in the serum of patients with mixed IgM : IgG cryoglobulinemia have been determined. The antigen IgG purified from five IgM cryoglobulins and the residual IgG purified from serum depleted of cryoglobulin were radiolabelled and co-isoelectric focused in polyacrylamide gels in order to determine if the IgM anti-globulin reacted with IgGs having unique physicochemical properties. Electrofocusing profiles of the IgG from four sera showed only minor differences when the antigen-IgG was compared to residual serum IgG. In one instance, the IEF profile of the antigen-IgG pool was markedly restricted and of a different charge dispersion than the residual serum IgG. This correlated with the limited antigenic specificity previously shown for the autologous IgM antiglobulin. [ABSTRACT FROM AUTHOR]

In essential mixed, type IL cryoglobulinaemia (EMC) monoclonal autoantibodies with rheumatoid factor activity are synthesized at an accelerated rate by non-malignant B lymphocytes. In order to determine if the high cryoglobulin production rate is related to a clonal B cell expansion, ceil surface markers of peripheral blood lymphocytes (PBL) were analysed by flow cytometry and the rearrangement of immunoglobulin (Ig) genes was investigated by Southern blot analysis of DNA extracted from the PBL of 12 EMC patients. Clonal expansion of B cells could be detected using DNA probes specifie for the cκ, c-mu. and JH genes in four out of 12 patients, two of whom also showed specific expansions of mu heavy and kappa light chain bearing cells using flow cytometry. The rearrangement of the c-mye locus was also noted in one of the patients with detectable Ig gene rearrangements. Demonstration of clonal B cell expansions in EMC patients shows that the clonal type of Ig gene rearrangements arc not unique markers of malignant lymphomas but may also occur in autoimmune lymphoproliferative disorders. Since malignant B cell lymphomas can develop in a small number of EMC cases, the follow-up of these patients should be pursued indefinitely. [ABSTRACT FROM AUTHOR]

Evidence is provided which supports the concept that a previously characterized monoclonal IgA-λ rheumatoid factor with a medium-binding avidity reacts with a select Fc region antigenic determinant. The interaction between this rheumatoid factor and anti-Rh-coated human erythrocytes is inhibited by IgG1 Fc fragment, IgG1 heavy chains, and a single peptide pool isolated from this tryptic digest by paper chromatography. Cyanogen bromide cleavage of the isolated heavy chains abolishes this reactivity. A methionine residue is assumed to be near, involved in, or necessary for reactivity between the IgA and its antigenic determinant. The data thus provide further evidence for a specific autoantigenic, rheumatoid factor-reactive determinant. [ABSTRACT FROM AUTHOR]

The article presents a discussion related to the immunohaematological cross-allergenicity between penicillin and cephalothin in humans. The immunogenieity of cephalothin and its cross-reactivity with penicillin were studied in a series of 174 adult patients receiving intravenous sodium celphalothin or intravenous penicillin-G. Immunogenieity was indicated by a higher incidence of anti-cephalothin antibody in patients after having received the drug than in controls and by an increase in liter of anti-cephalothin antibody.

Presents a case study of a patient with cyrstaglobulimemia syndrome. Medical history; Results of the physical examination of the patient; Treatment given to the patient.

Influenza epidemics are associated with significant morbidity and mortality in the elderly, with a substantial proportion of deaths due to cardiovascular events. Elevations of acute-phase proteins have been associated with an increased risk of atherosclerotic events. Therefore, serum amyloid A (SAA) and C-reactive protein (CRP) were measured during influenza illness and 4 weeks later in 7 young persons, 15 elderly outpatients, and 36 hospitalized adults. Striking elevations were seen in mean acute SAA and CRP levels in all groups, but hospitalized patients had the highest levels (SAA, 503 vs. 310 microg/mL [P=.006]; CRP, 120 vs. 34 microg/mL [P<.001]). The presence of dyspnea, wheezing, and fever was also associated with high CRP levels. Influenza infection is associated with significant elevations of SAA and CRP levels in elderly patients, especially those who require hospitalization. It is possible that direct effects of CRP may exacerbate preexisting atherosclerotic lesions and may help explain cardiovascular events associated with acute influenza.

The efficacy of granulocyte-macrophage colony-stimulating factor (GM-CSF) to enhance the primary immune response to hepatitis B vaccine was studied in healthy elderly with young volunteers included as controls in this double-blind, placebo-controlled trial of GM-CSF as an immune adjuvant. Naïve T-helper cells (CD4+CD45RA+) were determined at baseline. Forty-five healthy elderly (average age, 74 years) and 37 healthy young controls (average age, 28 years) were randomized. Hepatitis B vaccine was administered at 0, 1, and 6 months. GM-CSF as a single injection of either 80 microg or 250 microg with the first and second doses of hepatitis B vaccine. In this trial GM-CSF did not enhance antibody responses. However, the antibody responses were dramatically different between these two groups: 35/35 young developed a protective titer versus 19/45 elderly (P < 0.0001). In addition, the mean logarithm of anti-hepatitis B antibody level in the 35 young who completed the study was 3.17 (log mIU/ml) but only 2.21 in the 19 elderly responders (P < 0.0001). Naïve T-helper cells differed significantly between the two groups: the mean percentage of CD4+CD45RA+ T cells was 47.9% versus 35.0% (P < 0.0001) in the young and elderly volunteers respectively. Naïve T cells also differed significantly between elderly who did or did not respond to HBV (39.9% vs. 31.7%, P = 0.039). Using linear regression, age, and percent naive, CD4 T cells were determined to significantly influence the anti-hepatitis B antibody response, but sex and dose of GM-CSF did not. For a two-parameter model: logarithm of antibody titer = (-0.038 x age in years) + (0.031 x % naïve CD4T cells) + 2.68; adjusted r2 = 0.605 and P < 0.0001. However, age had a larger effect than naive CD4 T cells, i.e., in comparing young and elderly groups the log antibody titer decreased by 1.73 due to the increase in age but only 0.40 due to the decrease in naive CD4 T cells. Thus, there was a large effect of age that could not be explained by the quantitative change in the naïve T-helper cells.