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At least 919 records · Page 51Linked to original sources
PubMed1976

C4 synthesis in C4-deficient guinea pig radiation chimeras: restoration of the classic complement pathway.

Bone marrow transplants from normal Albany strain guinea pigs established a functional classical pathway of complement (C) in C4-deficient (C4D) guinea pigs. Seventeen days after transplant the Albany leads to C4D chimeras had detectable C4 and total hemolytic C activities. Maximum C4 levels (2 to 8% of normal were reachered by day 73 and restored total C to 40% of normal. Classical pathway function persisted for about 150 days and, thereafter, declined to undetectable levels by day 385. In contrast, Albany guinea pigs transplanted with C4D marrow maintained normal C4 levels throughout the experiment, suggesting that the C4-producing cells are radioresistant and long-lived. Unlike unmanipulated C4D animals, Albany leads to C4D chimeras were unable to produce antibodies to guinea pig C4 when immunized with normal guinea pig serum. These experiments suggest that bone marrow cell progeny produce C4 in vivo.

Animals↗
PubMed1978

Circulating immune complexes in syphilis.

13 patients with syphilis were investigated regarding the presence of circulating immune complexes by the methods of C 1q-binding-activity and anticomplementarity. Elevated C1q-binding-activity was demonstrated in 6 of 7 patients with secondary syphilis, a significantly greater incidence than among patients with primary syphilis and neurosyphilis. Anticomplementarity was demonstrated in five of seven patients with secondary syphilis and in two patients with neurosyphilis. Anticomplementarity was found in only one of four patients with primary syphilis. The presence of immune complexes may be of importance in the aetiology of some of the lesions of secondary and perhaps tertiary syphilis.

Antigen-Antibody Complex↗
PubMed1976

Immunofluorescent studies on the trabecular meshwork in open-angle glaucoma.

The trabecular meshwork of eyes with open-angle glaucoma has been demonstrated to have an increase in gamma globulin and plasma cells, raising the question of an immunogenic mechanism in this disorder. In the present study, however, immunofluorescence assays on the trabecular meshwork of eyes with open-angle glaucoma were negative for specific immunoglobulins and for complement components that would result specifically from an antigen-antibody reaction. The study fails to provide any evidence in support of an immunogenic mechanism in open-angle glaucoma.

Adult↗
PubMed1975

In vitro synthesis of some complement components (C1q, C3 and C4) by lymphoid tissues and circulating leucocytes in man.

Human lymphoid tissues and peripheral blood leucocytes and monocytes were studies with respect to the synthesis of complement components (C1q, C3 and C4) using an in vitro culture technique. All of the lymphoid tissues investigated (bone marrow, thymus, lymph node, spleen, tonsil, adenoid) synthesize complement components in different patterns. C3 was produced by all lymphoid tissues except the spleen, which was the only lymphoid tissue in which C4 production was regularly found. C1q synthesis was demonstrated in the spleen and adenoid cultures, and occasionally also in those of lymph node tissue. Lymphocytes in peripheral blood from normal individuals and in thoracic duct lymph, and also from patients suffering from chronic lymphatic leukaemia, do not synthesize any of these complement components. Peripheral blood leucocyte samples from normal individuals, containing 60 per cent lymphocytes and 40 per cent monocytes, do synthesize C3, however. Separation of the monocytes from these samples showed that it was in these cells that the synthesis of C3 occurred. Production of C3 by mononuclear phagocytes is also supported by the finding that peripheral blood leucocytes from patients suffering from acute monocytic leukaemia synthesize C3. C1q and C4 synthesis could not be demonstrated in any of the cultures of circulating leucocytes.

Adenoids↗
PubMed1975

Deficiencies of the complement system in man.

Deficiencies of components of the complement system in man are described. Clq was reconstituted in patients with severe combined immunodeficiency after bone marrow transplantation. Clr deficiency is associated with vascular disease and upper respiratory infections. Reconstitution of complement occurred in one patient with Clr deficiency after kidney transplantation. Our C2-deficient patient who developed systemic lupus erythematosus had elevated levels of C3. Following blood transfusion, ie by providing C2, dramatic activation of complement occurred in vivo.

Blood Bactericidal Activity↗
PubMed1975

Hereditary C2 deficiency in systemic lupus erythematosus and acquired complement abnormalities in an unusual SLE-related syndrome.

Early study of kindreds with C2 deficiency indicated that absence of C2 had no detrimental effect on affected individuals. Studies of additional kindreds, however, show a high incidence of SLE and other connective tissue diseases among homozygous C2-deficient members. A group of patients with an unusual SLE-related syndrome is described. In common with certain SLE patients they have marked depression of early complement components and presence of circulating Clq precipitins. It is suggested that early complement components are involved in specific host defense mechanisms and deficiencies of these components may predispose to such diseases.

Antibodies, Antinuclear↗
PubMed1975

Pemphigus and myasthenia gravis.

Various forms of true pemphigus have been reported to occur with myasthenia gravis, with and without thymoma, more frequently than can be ascribed to chance. A57-year-old woman with myasthenia gravis in remission developed pemphigus foliaceus. No roentgenologic evidence of a thymoma was present. Antinuclear antibodies caused interference with indirect immunofluorescent determination of pemphigus antibody. Indirect immunofluorescent studies showed no evidence for cross-reactivity between intercellular substance antibody and thymic components, as is found in the case of antiskeletal muscle antibodies with thymic myoid cells. The concurrence of these two diseases may involve the failure of a subgroup of thymic-dependent lymphocytes to suppress underlying autoimmune phenomena.

Animals↗
PubMed1976

The chemoattraction of neutrophils by heterologous and homologous cytotoxic sera.

Neutrophils (PMN) migrated in vitro chemotactically along concentration gradients of heterologous and homologous leukocytotoxic, complement-active sera. The heterologous systems consisted of normal, non-immune nurse shark or dog serum and human PMN; the homologous systems consisted of human or dog immune sera and human or dog PMN, respectively. Chemotaxis was induced 1) by fresh cytotoxic sera, 2) by complement alone if the cytotoxic antibodies were with the responding cells or if the cells were passively sensitized with the antibodies, and 3) by individual and combined complement components if the corresponding intermediate PMN-antibody-complement component complexes were the migrating cells. These observations represent a new mechanism of immune chemotaxis: the chemotactic stimulation is a direct consequence of a gradient-controlled immune reaction occuring at and involving the surface of the chemoattracted cell. This mechanism is distinctly different from that which depends on chemotactic factors produced or released independent of and at a distance from the responding cells.

Animals↗
PubMed1976

In vitro activation of C1s in plasma of patients with hereditary angioneurotic oedema.

The serum of patients with hereditary angioneurotic oedema contains small amounts of inhibitor of Cl-esterase (Cl-s) which is usually present in appreciable amounts in the serum of healthy individuals. In the citrated plasma of these patients in remission Cl-s activity was not detectable, but prolonged incubation with various alcohols, detergents, acetone, phenols and metal chelating agents generated the enzyme. Normal plasma did not respond to these reagents. The generation of Cl-s by alcohol and EDTA was inhibited by addition of natural inhibitor of Cl-s but not by soyabean trypsin inhibitor, trasylol and hexadimethrine bromide. Hexadimethrine bromide did not block the generation when experiments were carried out in silicon coated glassware. Incubation with kaolin and kallikrein generated Cl-s in remission plasma. Density gradient centrifugation studies showed that alcohol caused at least partial dissociation of Cl in remission plasma but not in normal plasma. This effect was similar to that of EDTA described in earlier reports. The possible explanations for the findings are discussed.

Alcohols↗
PubMed1977

Immunosuppression of T lymphocyte function by fractionated serum from tumor-bearing mice.

Sera from mice with transplanted 3-methylcholantrene-induced tumors have been shown previously to inhibit the function of normal lymphoid cells. When chromatographed on Sephadex G-150, the fraction eluting with immunoglobulin has been shown to inhibit the proliferative response of normal spleen cells to concanavalin A and to inhibit the in vitro antibody response to a T-dependent antigen, but has a lesser effect on the antibody response to a T-independent antigen. This paper deals with studies on the mode of action of the serum factor. The immunoglobulin containing fraction of serum from tumor-bearing mice inhibited the in vitro generation of both allogeneic and syngeneic cytotoxic lymphocytes. Time course studies demonstrate that the serum fraction inhibits the generation of antibody-producing and cytotoxic lymphocytes if added during the first 2 days of a 5-day culture. Serum fractions added after day 2 had no effect on the in vitro response. The serum factor appears to inhibit the generation of specific T cell function during the proliferative stage of development but has no effect on the differentiation stage which leads to either antibody-producing cells or cytotoxic lymphocytes.

Chemical Precipitation↗
PubMed1979

Immunobiological aspects of Clq in sera of patients with cutaneous vasculitis and collagen diseases.

Clq was comparatively quantified with CH50 or C3 in sera of patients with various types of cutaneous vasculitis and collagen diseases. The following results were found: 1) Elevated levels of Clq were seen much more frequently in cutaneous vasculitis and PSS. 2) No significant correlations were found between Clq and CH50 or C3, except for a moderate rank correlation between Clq and C3 in SLE. 3) The amount of hydroxyproline in serum (collagen-like protein) is nearly identical with the calculated value of that present in Clq.

Adolescent↗
PubMed1977

Functional affinity constants of the reaction between 125I-labelled C1q and C1q binders and their use in the measurement of plasma C1q concentrations.

Purified 125I-labelled C1q has been found to react with glutaraldehyde-treated red cells (glut-RBC), with a value for the functional affinity constant, K, of 1-3 X 10(8) M-1, based on measurement of concentrations of bound and free reactants at equilibrium. Values of K obtained for other C1q-binders were as follows: diaminopropane, 2 X 10(2) M-1; monomer IgG, 5 X 10(4) M-1; heat-aggregated IgG, 0-5-2-5 X 10(8) M-1; IgG-anti-IgG complexes, 0-31 X 10(8) M-1. The functional rate constant for association (ka) between 125I-labelled C1q and glut-RBC was 5 X 10(5) M-1 S-1 at 37 degrees in 0-17 M NaC1. The rate of dissociation of the C1q-glut-RBC complex was biphasic with rate constants (kd) of 2 X 10(2) S-1 and 2 X 10(5) S-1. Calculated values of K from the ration ka/kd gave values of 2-5 X 10(7) M-1 and 2-5 X 10(10) M-1. It is suggested that the range of values of K reflects the involvement of 1,2 or more binding sites on the C1q molecule. Reduction of the ionic strength of the medium from 0-17 M to 0-14 M increases the rate of association of C1q and glut-RBC eleven-fold, indicating involvement of ionized groups at the binding site. A method is described for measuring plasma C1q concentrations by saturation assay, using 125I-labelled C1q and glut-RBC. Plasma C1q concentrations fell in the range 170-250 microng/ml.

Binding Sites↗
PubMed1977

[Adult papular acrodermatitis (Gianotti's disease). Report of 3 cases].

The authors report three cases of adult papular acrodermatitis with circulating HBs antigen. The eruption was followed by a benign icteric hepatitis which lasted from 30 to 45 days. In two cases, HBs antigen disappeared in a one month period, in one case the antigen has been present for more than three months. Direct immunofluorescence staining exhibits c3 deposits in the vessels of the dermal lesions, without any deposition of immunoglobulins or fibrinogen. We were unable to demonstrate the presence of HBs and " e " antigens in the skin lesions (using FITC conjugated specific antiserums). Serum protein concentrations of complement components C1q, C4,C3, C3PA were normal as measured by radial immunodiffusion. The percentage of circulating B and T cells was normal, as essayed by E-RFC, EAC-RFC and sIg. Thus, adult papular acrodermatitis, as well as the infantile form, does represent a sign of invasion of a benign viral hepatitis.

Acrodermatitis↗