Lack of adherence of IgG-, IgM-, and C3b-sensitized erythrocytes to human heart valves

In a search for receptors for immunoglobulin Fc fragment and activated complement component C3 (C3b) in normal or rheumatic heart valve tissues, sheep erythrocytes sensitized with IgM (IgM EA), IgG (IgG EA) and IgM plus activated complement (IgM EA C3b) were used in a closed-chamber immune adherence technique. Neither this method nor a separate immunofluorescence technique revealed the presence of such immunologic receptors in frozen sections of heart valves.

A serum antibody in patients with rheumatoid arthritis stimulates cathepsin B activity in peritoneal mouse macrophages

Mouse peritoneal macrophages were stimulated by sera from patients with active rheumatoid arthritis (RA) to increased intracellular cathepsin B activity. By gel filtration of three RA sera, the stimulatory activity was found in the IgG and to a lesser extent in the IgM containing fraction. The DEAE-cellulose purified IgG preparations of five additional RA patients stimulated intracellular cathepsin B activity significantly above IgG from healthy controls. IgG and IgM antibodies to macrophages were detected in sera from RA patients but not from controls by indirect immunofluorescence (IIF) technique. Pepsin F (ab')2 fragments of IgG from the RA patients also gave clearcut membrane fluorescent staining of the macrophages which demonstrated the antibody nature of the binding. A good correlation between the cathepsin B assay and the IIF was found when serial dilutions of serum were compared.

Amyloid-related serum protein (SAA) as an indicator of lung infection in cystic fibrosis

Amyloid-related serum protein (SAA) was analysed by radioimmunoassay in 32 patients with cystic fibrosis, and compared with other acute phase reactants and lung function. The level of SAA showed significant correlation with impaired lung function due to active Pseudomonas aeruginosa infection, and also to C-reactive protein. SAA seemed to correlate better to the presence of bacteria in sputum than C-reactive protein. Ten of the patients received extensive antibiotic treatment for their pulmonary infection, and falling serum levels of SAA paralleled the clinical response to treatment. Thus the concentration of SAA in these patients was a valuable guide for the selection of patients for antibiotic treatment as well as a good parameter of the response to therapy.

Immunoglobulin-related (AL) amyloidosis

The amyloid fibril is the unique component of amyloid substances. Some amyloid fibrils (i.e. AL amyloid) are made up by homogeneous immunoglobulin light chains, and such fibrils are related to systemic and localized primary amyloidosis and amyloidosis associated with myelomatosis and Waldenstrøm's macroglobulinaemia. More lambda than kappa light chain proteins make up the amyloid in these cases, and it appears that lambda-chains are more prone to fibril formation than kappa-chains. Immunoglobulins are thus the precursor protein for AL amyloid, which shows that primary amyloidosis belongs to the plasma cell dyscrasias. Amyloid infiltration of the heart and the kidneys accounts for the most severe clinical consequences of AL amyloidosis. In addition, peripheral neuropathy, carpal tunnel syndrome, macroglossia, skin affections, amyloid arthropathy and autonomic disturbances (i.e. orthostatic hypotension) are characteristic features of the disease. Involvement of parenchymal organs (kidneys, liver, spleen, gastrointestinal tract and endocrine glands) are common to systemic AL amyloidosis and secondary amyloidosis. As protein AA is the major fibril constituent of secondary amyloid, this form of amyloid disease is not related to immunoglobulins. Like other forms of plasma cell dyscrasia, patients with AL amyloidosis are usually treated with cytotoxic drugs and corticosteroids, however, the prognosis is very poor with a reported survival time after diagnosis of less than two years.

The covalent structure of amyloid-related serum protein SAA from two patients with inflammatory disease

The complete covalent structure of an amyloid-related serum protein SAA from a patient (Jen.) with severe rheumatoid arthritis, is presented. The structure was elucidated by N-terminal analyses of the protein as well as on peptides derived from tryptic digestion and after cleaving the protein with BNPS-skatole. The characterization of tryptic peptide T-9 revealed a polymorphism similar to that seen in protein AA. Structural studies performed on another protein SAA, isolated from a patient (Mik.) with acute systemic lupus erythematosus, indicated that this protein is homologous to that from patient Jen. The formation and deposition of the protein AA-containing amyloid fibrils is discussed.

Studies on humoral immunity in pregnancy: immunoglobulins, alloantibodies and autoantibodies in healthy pregnant women and in pregnant women with rheumatoid disease

Levels of immunoglobulins, alloantibodies and the presence of autoantibodies were prospectively studied during and after pregnancy in healthy women and in women suffering from rheumatoid arthritis (RA) and ankylosing spondylitis (AS). A decrease of IgG and IgA during pregnancy was found in all women while levels of IgM and alloantibodies remained stable. Multiparous women had higher levels of IgG during pregnancy when compared to primigravidae. No difference in the frequency of rheumatoid factor (RF) or antinuclear antibodies (ANA) was found when healthy pregnant women were compared to healthy non pregnant controls. None of the RF negative patients conversed to seropositivity during or after pregnancy. Decrease of ANA was correlated to remission of disease activity in the patients with RA.

Comparative studies of the high molecular weight amyloid fibril proteins and similar components from normal tissues

Analysis of purified amyloid fibrils by gel filtration, polyacrylamide gel electrophoresis in SDS and 8 M urea, and immunodiffusion and immunoelectrophoresis showed that, in addition to the specific amyloid proteins AA and AL, the amyloid preparations all contain a high molecular weight complex. The latter protein complex contains fibronectin, a component which reacts with a non-AA specificity of an antiserum to degraded AA amyloid fibrils (termed the 'B' specificity), and a high molecular weight component excluded by a Sepharose 2BCL column. Similar components were found in aqueous extracts of normal tissues prepared by an identical procedure, and these form aggregates of different size in non-dissociating conditions. It is suggested that amyloid fibrils are complexes of a variety of macromolecules in addition to the specific proteins AA and AL.

The association between rheumatoid arthritis and the HLA antigen DR4

One hundred and forty-two patients with 'definite' or 'classical' rheumatoid arthritis (RA) were studied for the frequency and possible prognostic significance of HLA DR4. Of these, 122 were seropositive, while 20 were negative for rheumatoid factor (RF) in serum. The HLA antigen DR4 was significantly increased in the seropositive group (65%) as well as in the seronegative group (55%) in comparison with a frequency of 27% in 116 healthy controls. Among seropositive patients a higher frequency of DR4 was found in females (73%) than in males (50%), the difference being statistically significant (p less than 0.01). DR4 was more frequent among patients with a family history of RA (74%) than among patients without affected relatives (57%). DR4 appeared to be associated with an early onset of RA. No significant differences in general disease activity or functional capacity between DR4-positive and DR4-negative RA patients were found. Patients without the HLA antigen DR4 had a significantly (p less than 0.05) higher mean titre of RF than those with the antigen.

HLA DR antigens and gold toxicity

One hundred and thirty-two patients with rheumatoid arthritis treated with gold have been studied for possible associations between HLA DR antigens and different adverse reactions occurring during such therapy. Patients possessing HLA DR3 had a significantly greater frequency of side effects than patients lacking this antigen. It was particularly noticed that DR3 positive patients on gold treatment had an 11 times higher risk of getting proteinuria than those without DR3. The lowest frequency of side effects was seen in DR7 positives. No significant differences between the DR antigen groups with respect to skin eruptions, liver reactions, or leucopenia were evident.

Tissue distribution of lymphocytes in rheumatic heart valves as defined by monoclonal anti-T cell antibodies

Fresh cardiac valvular tissues and atrial appendages removed from 106 Indian patients with rheumatic heart disease at the time of corrective cardiac surgery were examined to determine the characteristics of valvular interstitial lymphocytic infiltrates using conventional histologic staining along with indirect immunofluorescent techniques. Precise identification of the phenotypic profiles of inflammatory mononuclear cells was attempted using anti-IgG, anti-Ia, and monoclonal mouse hybridoma reagents identifying T cells (OKT3) as well as T cell subsets (OKT4 helper/inducer and OKT8 suppressor/cytotoxic cells). A similar group of 21 patients undergoing cardiac valvular resection in Albuquerque was studied. The mean age of Indian patients providing valve tissues was 27.7, whereas in those in Albuquerque, it was 52 years. Twenty-five percent of rheumatic heart valves in Indian patients showed significant interstitial lymphoid infiltrates, and one third of the rheumatic valves from patients in Albuquerque showed similar mononuclear cell collections. Lymphoid infiltrates contained a predominance of T cells (70 to 80 percent) and only occasional B cells. Most of the T cells were OKT4-positive, with only a minor representation of suppressor/cytotoxic OKT8-positive T cells. In many instances, OKT4-positive helper T cell collections were closely juxtaposed to fibroblasts and collagen fibrils. These findings suggest that the chronic rheumatic scarring process may involve helper/inducer T cells as an ancillary factor in the indolent contracture and fibrosis of deformed cardiac valvular structures. Attempts to demonstrate residual streptococcal antigens by indirect immunofluorescence using a wide panel of heterologous rabbit F(ab')2 reagents with specificity for group A streptococcal membranes, cell wall mucopeptide, or group A carbohydrate gave negative results.

HLA DR antigens in rheumatoid arthritis

The prevalence and possible prognostic significance of HLA-DR antigens have been studied in 129 patients with seropositive (RF-positive) classical rheumatoid arthritis (RA). HLA-DR4 was increased in RA, whilst HLA-DR2 was decreased, though it was not associated with either low titres of RF or with good prognosis. HLA-DR3-positive patients had the highest prevalence of antibodies to nuclear antigens, and the antigen correlated negatively to the presence of subcutaneous nodules, bony erosions and familial RA. RA patients possessing DR3 thus had some of the characteristics of SLE. HLA-DR5 was not present in male RA patients. An absence of familial RA was observed among DRw8-positive patients.

Stimulation of murine macrophage cathepsin B by serum from patients with rheumatoid arthritis: an indicator of disease activity

Cultures of non-elicited mouse peritoneal macrophages were used as a test system to study the effect of sera from patients with rheumatoid arthritis (RA) on intra-cellular cathepsin B activity of macrophages. Sequential sera obtained during and after pregnancy from six RA patients, and sera from six actively ill, non-pregnant RA patients were compared to six healthy female controls and 3rd trimester healthy women. Sera from actively ill RA patients (both pregnant and non-pregnant) caused macrophage cathepsin B levels significantly above normal controls, while intra-cellular activities of beta-glucuronidase and N-acetyl-glucosaminidase did not differ from the controls. A significant correlation between activity of RA and intracellular cathepsin B was found in pregnant patients. It is suggested that a factor (or factors) present in serum from patients with active RA causes a rise of intracellular cathepsin B in macrophages.

Comparison between serum alpha 2-pregnancy-associated globulin and activity of rheumatoid arthritis and ankylosing spondylitis during pregnancy

A possible association between alpha 2-pregnancy-associated globulin (alpha 2-PAG) and activity of rheumatoid arthritis (RA) during pregnancy was investigated. In a prospective study, the correlation between disease activity and serum alpha 2-PAG levels during and after pregnancy was evaluated in 11 women with RA. For comparison, 12 women with ankylosing spondylitis (AS) and 14 healthy women were also studied. No correlation between improvement of disease activity and serum alpha 2-PAG levels could be detected in pregnant RA or AS patients. In contrast, a positive association between total disease activity score and serum alpha 2-PAG levels was found in pregnant RA and AS patients.

Effect of pregnancy and hormonal changes on the activity of rheumatoid arthritis

The effect of pregnancy on the activity of rheumatoid arthritis (RA) was evaluated in 31 patients who had given birth to 49 infants after the onset of their disease. Pregnancy-associated remission of RA was experienced by 75% of the patients. On the other hand, disease exacerbation after delivery occurred in 62% of them. RA had no harmful effect on pregnancy or on the fetus. Hormonal changes during the menstrual cycle or during the use of hormonal contraceptives did not seem to influence the symptoms of RA. Factors possibly involved in remission of RA during pregnancy are discussed.

Monoclonal hybridoma antibodies to human amyloid related protein SAA

Problems concerning isolation and characterization of the amyloid related serum protein SAA in a pure form prompted us to make monoclonal antibodies to the protein. Protein SAA isolated by gel filtration under dissociating conditions was used for immunization of BALB/c mice, and spleen cells from a mouse producing high titred antiserum to SAA were fused with cells from the mouse plasmacytoma line P3U1. Antibody specificity to various preparations of protein SAA was tested using an indirect enzyme-linked immunosorbent assay. Monoclonal antibodies with specificity for SAA were obtained in addition to antibodies which reacted with both SAA and the related amyloid protein AA. Antibodies specific for one of the apoC proteins of the lipoprotein fraction were also produced showing that the SAA preparation used for immunization was contaminated with apoC proteins.

Characterization of amyloid related protein SAA complexed with serum lipoproteins (apoSAA)

The amyloid related protein SAA was isolated from the serum lipoproteins of three patients with connective tissue disease, one of them having amyloidosis, and from a pool of normal control sera. The bulk of SAA (apoSAA) was complexed to high density lipoprotein (HDL), but significant amounts of apoSAA were also detected in the other lipoprotein fractions. Electrofocusing revealed five-six subspecies of SAA which were distributed in similar proportions in HDL and LDL. Three of these SAA subspecies made up almost all of the apoSAA present in HDL and LDL in the sera from the patients as well as in the control. A small portion of SAA not complexed to lipoproteins was isolated corresponding to a molecular weight higher than 200,000. No particular 'amyloid prone' SAA was found in serum from the patient with amyloidosis.

Immunohistochemical characterization of hepatic tissue lymphocyte subpopulations in liver disease

Liver biopsies from 27 patients were studied by the indirect immunofluorescence and immunoperoxidase technique for relative distribution of B cells and T-cell subpopulations. T-cell subsets were defined for OKT4(+) (helper/inducer) and OKT8(+) (suppressor/cytotoxic) cells by using mouse hybridoma monoclonal antibodies. Patients with chronic active hepatitis and those with primary biliary cirrhosis showed marked relative increments in suppressor/cytotoxic OKT8(+) lymphocytes within hepatic lymphocytic infiltrates. Other patients with acute hepatitis or those with only reactive changes also showed a relative increment in OKT8(+) T lymphocytes within hepatic biopsy material. These findings suggest that tissue lymphocytic subpopulation increments in suppressor/cytotoxic T-cell subpopulations are commonly associated with hepatic lymphocytic infiltrates and may be related to disorders of immune regulation or expression in some of these disorders.

Amyloid A in systemic amyloidosis associated with cancer

Amyloid fibrils from two cases of cancer-associated, systemic amyloidosis with renal cell carcinoma and mesothelioma as the respective underlying disorders were studied. The immunochemical studies suggested strongly that amyloid A comprised a principal fibril component in both cases of cancer-associated amyloidosis. This was definitively proven by amino acid sequence analyses, which revealed structural homology between a purified subcomponent of the amyloid fibrils from both of the two cases of cancer-associated amyloidosis and previously sequenced amyloid A proteins. The chemical composition of the amyloid fibrils from systemic amyloidosis associated with cancer thus corresponded to that seen in amyloidosis reactive to inflammatory diseases and Hodgkin's disease. Amyloid proteins of immunoglobulin light chain type, which are found associated with myelomatosis, macroglobulinemia, and idiopathic (primary) amyloidosis, were not found in the two amyloid preparations. Renal cell carcinoma appears to be an effective stimulator of amyloid formation, while only one case of amyloidosis associated with mesothelioma has been reported previously.