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PubMed1984

Macrophages of athymic nude mice: Fc receptors, C receptors, phagocytic and pinocytic activities.

Expression of Fc receptors (FcR) for IgG1, IgG2A, IgG2B, IgM, IgA and IgE, binding of C3 and C5 complement components and phagocytic and pinocytic activities were determined in peritoneal and omental macrophages of nu/nu, nu/+ and +/+ Balb/c mice. nu/nu mice showed a higher proportion of FcR and complement receptor-bearing peritoneal macrophages along with a significantly higher phagocytic activity of peritoneal macrophages both in vitro and in vivo. Tests of pinocytic activity in these cells and phagocytic activity in omental phagocytes yielded similar results. We conclude that athymic mice compensate their immune defects by a higher phagocytic activity of their professional phagocytes and a higher expression of receptors mediating this process.

Animals↗
PubMed1984

Polymorphonuclear leucocyte locomotion and aggregation in patients with alcoholic liver disease.

Defects in stimulated movement of polymorphonuclear (PMN) leucocytes was detected in 57% of patients with alcoholic liver disease. Serum from patients with the cellular defect had no effect on the function of normal PMN leucocytes. Aggregation responses of patients' PMN leucocytes suggest that the cellular defect may be related to specific abnormalities in the response to the C5a chemotactic factor. Defective serum attractant activity was found in 65% of the patients tested and the presence in the patients serum of humoral directed antagonists appeared to be responsible for the defect in majority of cases. Further analysis pointed to the presence of at least two distinct antagonists and the possible involvement of proteases in this serum abnormality. The activity of the serum antagonists or the severity of the cellular defect were unrelated to the presence of bacterial infection or elevations in serum IgA or IgG. The high frequency of cellular defects, possibly as a result of in vivo activation, in conjunction with serum abnormalities could account for the increased susceptibility of patients with alcoholic liver disease to bacterial infection.

Adult↗
PubMed1977

Complement-induced histamine release from human basophils. III. Effect of pharmacologic agents.

Human serum activated with zymosan generates a factor (C5a) that releases histamine from autologous basophils. Previously we have presented evidence that this mechanism for C5a-induced release differs from IgE-mediated reactions. The effect of several pharmacologic agents known to alter IgE-mediated release was studied to determine whether they have a similar action on serum-induced release. Deuterium oxide (D2O), which enhances allergic release, inhibited in a concentration-dependent fashion the serum-induced reaction at incubation temperatures of 25 and 32 degrees C. The colchicine-induced inhibition was not reversed by D2O. Cytochalasin B, which gives a variable enhancement of IgE-mediated release, had a marked enhancing effect on the serum-induced reaction in all subjects tested. The following agents known to inhibit the IgE-mediated reaction also inhibited serum-induced release at 25 degrees C: colchicine, dibutyryl cyclic AMP, aminophylline, isoproterenol, cholera toxin, chlorphenesin, diethylcarbamazine, and 2-deoxy-D-glucose. These results suggest that the serum-induced release is modulated by intracellular cyclic AMP, requires energy, and is enhanced by the disruption of microfilaments. The lack of an effect by D2O would suggest that microtubular stabilization is not required. The data can be interpreted to indicate that IgE- and C5a-mediated reactions diverge at a late stage in the histamine release pathway.

Aminophylline↗
PubMed1983

Anaphylatoxin-mediated regulation of the immune response. II. C5a-mediated enhancement of human humoral and T cell-mediated immune responses.

C5a derived from the fifth component of human complement was found to potentiate both specific and non-specific human in vitro humoral immune responses. In addition, C5a is capable of potentiating antigen- and alloantigen-induced T cell proliferative responses. In contrast to these results, C5a was unable to modulate mitogen-induced B and T cell proliferative responses. The carboxyterminal arginine of C5a is not essential in order for C5a to enhance immune responses. C5ades Arg was found to augment the immune response to the level of C5a-mediated enhancement. The serum carboxypeptidase inhibitor, 2-mercaptomethyl-5-quanodinopentanoic acid, which prevents cleavage of the terminal arginine, allowed us to assay the effects of C5a on in vitro immune responses in the presence of serum. Helper T cells are involved in C5a-mediated immuno-potentiation. Substitution of T cells by soluble T cell-replacing factors, (Fc)TRF, rendered lymphocyte cultures refractory to the enhancing properties of C5a.

Adult↗
PubMed1984

Plasma lactoferrin reflects granulocyte activation via complement in burn patients.

Complement activation and neutropenia have been observed in thermally injured animals. In burn patients, granulocyte chemotaxis and morphological loss of specific granules occur. We conjectured that complement is activated in humans and, in turn, induces granulocytes to secrete lactoferrin (LF), a marker of granulocyte activation. Twenty burn patients were evaluated for absolute granulocyte count (AGC), plasma levels of anaphylatoxins (C3a, C4a, C5a), and lactoferrin. The AGC directly correlated with the extent of the burn on day 1. Similarly, plasma LF on day 1 correlated with the percent burn. Those with greater than 30% burn had plasma LF between 10 and 40 micrograms/ml (normal LF = 1.5 +/- 1.8 micrograms/ml). In five patients without further complications followed serially, plasma LF did not return to normal until 2 to 5 weeks. In all patients, there was evidence of complement activation; C4a ranged between 283 and 13,064 ng/ml and C3a between 19 and 852 ng/ml. In some patients, C5a was detectable, but the values correlated inversely with the extent of burn. On the other hand C3a and C4a levels did not correlate with the extent of burn but threefold to fivefold rises of C3a levels on days 7 and 9 predicted gram-negative sepsis. Although plasma LF did not predict sepsis, levels greater than 12 micrograms/ml on day 1 heralded the onset of neutropenia on day 3 in 60% of patients with 30% burn. Six of 20 patients developed pulmonary radiographic changes and, in five of the six, the changes occurred by day 3. Plasma LF in all six patients on day 1 was greater than 17 micrograms/ml. In two patients with greater than 50% burn, depletion of granulocyte LF was demonstrated histochemically. These studies indicate that complement is activated in burn patients, which is associated with granulocyte secretion. Measurement of plasma anaphylatoxins and LF may serve as useful aides in clinical management of these patients.

Adult↗
PubMed1984

Role of complement in the immune response.

Evidence has accumulated that shows that fragments of C3 are potent inhibitors of immune responses. A low-molecular-weight fragment of C3 and fragments possessing leukocyte-mobilizing activity have been shown to block both antigen- and mitogen-induced human T cell proliferation, and to block mixed lymphocyte culture responses and the generation of cytotoxic lymphocytes. The same fragments inhibit the development of secondary in vitro antibody responses of rat lymphocytes. C3b can be shown to inhibit the polyclonal activation of human lymphocytes by pokeweed mitogen, but it has no effect on T cell proliferation or on the generation of cytotoxic T cells. We now propose that different C3 fragments selectively act on various lymphocyte subsets and thus play a profound role in regulating both immune effector functions and the intensity of the immune response.

Animals↗
PubMed1983

Abnormalities of lymphocyte locomotion in immunodeficiency disease.

Lymphocyte and neutrophil locomotion were studied in 23 patients with well defined, primary immunodeficiencies. These included eight patients with common variable immune deficiency, three patients with X-linked agammaglobulinaemia, two patients with the Wiskott-Aldrich syndrome, three patients with ataxia telangiectasia, three patients with immunodeficiency and normal serum immunoglobulin concentrations, one patient with immune deficiency and hyper-IgM syndrome, two patients with Job syndrome and one patient with a granulocyte adherence defect. Random and stimulated lymphocyte and neutrophil migration were evaluated. C5a and casein were used to stimulate lymphocyte migration and C5a and formyl-methionyl-leucyl-phenylalanine (f-MLP) were used to stimulate neutrophil migration. Significantly depressed lymphocyte migration in response to casein and C5a was observed in patients with common variable immune deficiency, patients with immune deficiency and normal immunoglobulin concentration, and patients with Job syndrome. No consistent defect in lymphocyte locomotion was observed in the other patients studied. Neutrophil migration in response to C5a and f-MLP was depressed in Job syndrome, the patient with a granulocyte adherence defect, one of the six patients with common variable immune deficiency and none of the remaining patients. No significant correlation of skin test reactivity and lymphocyte migration was noted, but a correlation between the degree of lymphocyte proliferation in response to phytohaemagglutinin and lymphocyte migration in response to casein was observed. The results presented indicate that aberrations in lymphocyte migration occur in several types of immunodeficiency diseases and that defects in lymphocyte and neutrophil migration can occur simultaneously or totally independent of each other.

Adolescent↗
PubMed1984

Chemotactic factors induced vimentin phosphorylation in rabbit peritoneal neutrophil.

Rabbit peritoneal neutrophils were reacted for 5-10 s with the chemotactic factors, fMet-Leu-Phe or (5S),(12R)-dihydroxy-6,8,11,14-(cis,trans,trans,cis)-eicosatetraenoic acid and then lysed with a solution of Triton X-100 and [gamma-32P]ATP. They showed an enhanced incorporation of 32P in Mr = 60,000- and 67,000-dalton polypeptides compared to control cells treated similarly. Another chemotactic factor, C5a, produced a similar but much lesser effect. The enhancement was not affected by the addition of the purified catalytic subunit of cAMP-dependent protein kinase, the inhibitor of cAMP-dependent protein kinase, or CaCl2, suggesting that the effect was not mediated by a cAMP-dependent or a Ca2+-dependent protein kinase. When analyzed by two-dimensional gel electrophoresis, the Mr = 60,000 phosphoprotein contained several phosphoproteins with different isoelectric points. The isoelectric point and molecular weight of one of them was similar to those of the intermediate filament protein, vimentin, purified from Chinese hamster ovary cells. Addition of the purified Chinese hamster ovary vimentin and [gamma-32P]ATP to the Triton X-100 lysate of fMet-Leu-Phe-treated neutrophils resulted as an enhanced incorporation of 32P into the vimentin. Addition of fMet-Leu-Phe to 32P-labeled intact neutrophils also enhanced incorporation of 32P into the vimentin of neutrophils. The results suggest that chemotactic factors stimulate vimentin phosphorylation in rabbit neutrophils.

Animals↗
PubMed1984

A C5a inhibitor in peritoneal fluid.

Peritoneal fluid was found to contain an inhibitor of neutrophil chemotaxis. The inhibitor was effective only against the chemotactic activity of zymosan-activated serum (including purified C5a) and had no effect when f-met-leu-phe served as chemoattractant. Inhibition was not the result of a direct effect on the neutrophils, since incubation of cells with the peritoneal fluid did not alter their chemotactic response. The inhibitor was found to be a protein with a molecular weight of approximately 40,000 dalton by gel filtration. It resembles the inhibitor previously described by us in synovial fluids, and thus it is proposed to play a role in the regulation of inflammation in serosal tissues.

Ascitic Fluid↗
PubMed1984

A role for sulfhydryl groups in granulocyte aggregation.

Polymorphonuclear leukocytes (PMN) stimulated by high concentrations of the complement component C5A form cellular aggregates, and both the rate and degree of aggregation are influenced by changes in the PMN plasma membrane and cytoskeleton. Since sulfhydryls are important constituents of the plasma membrane and cytoskeleton, we investigated the effect of agents that oxidize and bind sulfhydryls on C5A-induced aggregation. PMN incubated with diamide, a nonspecific sulfhydryl-oxidizing agent, had a marked increase in their aggregation response to C5A. Tertiary butyl hydroperoxide (BHP), which reacts specifically with the soluble sulfhydryl glutathione (GSH), had no effect on aggregation. The enhancement of PMN aggregation by diamide, but not BHP, suggested that oxidation of non-GSH sulfhydryls contributes to the aggregation response. To test the requirement for sulfhydryls in PMN aggregation, PMN were treated with the sulfhydryl-binding agent N-ethylmaleimide (NEM). NEM markedly impaired aggregation without affecting resting or methylene blue-stimulated [14C]-L-glucose oxidation of the granulocytes. P-chloromercuriphenyl sulfonic acid (PCMPSA), an external sulfhydryl-binding agent, had no effect on aggregation. These studies suggest that cellular sulfhydryls are required for optimal PMN aggregation and that oxidation of these sulfhydryls may be one of the biochemical changes that contributes to aggregation.

Cell Aggregation↗
PubMed1982

[Herpes gestationis: clinical and optic immunofluorescence findings].

Reported in this paper are two patients on whom gestational herpes was diagnosed by clinical examination as well as by optico-immunofluorescent checks. Direct immunofluorescence technique has now enabled diagnosis with higher accuracy of gestational herpes, a dermatosis specific of pregnancy, with diagnosis proper being preceded by identification of C3 and C5 complement fixation. In both cases, symptoms had appeared in the second trimester. They had started from the umbilical region and then affected the entire trunk and extremities. In one of the patients, symptoms disappeared immediately after delivery, while exacerbation was recordable from the second in the puerperium. The pathological process was controlled in either case by topical application of corticosteroids. The symptoms of these cases, diagnosed by optico-immunofluorescent methods, are compared with clinical reports about gestational herpes cases in earlier literature.

Adrenal Cortex Hormones↗
PubMed1982

Characterization of three macrophage chemotactic factors from PPD-induced delayed hypersensitivity reaction sites in guinea pigs, with special reference to a chemotactic lymphokine.

Three types of macrophage chemotactic factors (MCFs) were separated from purified protein derivative (PPD)-induced delayed hypersensitivity (DHR) skin lesions in guinea pigs, and MCF-c was purified isotachophoretically. The macrophage chemotactic activity (MCA) of the skin extract was mostly associated with MCF-a and c. MCF-c (mol wt 110,000) seemed more significant for mediating the macrophage reaction than MCF-a (mol wt 150,000), which exhibited common antigenicity with serum IgG. MCF-b (mol wt 14,000), manifesting common antigenicity with the fifth component of complement (C5), was apparently less significant. MCF-c was thermostable and had an isoelectric point (pI) of 5.2 +/- 0.1. The protein exhibited marked macrophage chemotactic activities (MCA) but no neutrophil chemotactic, lymphocyte chemotactic, and MIF activity in excess of that in vitro. Selective accumulation of macrophages was observed in response to intradermal MCF-c injection. Our studies suggest that MCF-c at 24-hour skin sites of DHR may exist as specific lymphokine preparations with high potential for monocyte infiltration.

Animals↗