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PubMed1983

Resistance and susceptibility of mice to bacterial infection. IV. Functional specificity in natural resistance to facultative intracellular bacteria.

The effect of opsonic antibody on resistance of susceptibility of three strains of mice, C57Bl/10, BALB/c, and CBA to the intracellular bacteria Listeria monocytogenes, Salmonella typhimurium, and Brucella abortus was tested. Bacteria were opsonized by serum treatment before their injection into mice, or the mice were preimmunized by injection with alcohol killed bacteria which induces antibody without macrophage activation. Antibody did not increase the rate of clearance of Listeria from the bloodstream, nor did it affect the subsequent growth of that organism in the spleen and liver. Blood clearance of S. typhimurium and of B. abortus was increased by preopsonization with specific antibody, indicating that opsonins were a limiting factor in resistance to these two bacteria. However, neither opsonization before infection nor immunization with alcohol killed vaccines had any effect on the strain distribution of resistance/susceptibility, which differs for each of the three intracellular pathogens. Thus, even in the presence of adequate opsonization the three strains of mice showed different patterns of resistance/susceptibility to Listeria, S. typhimurium, and B. abortus. This implies that each has a unique cellular mechanism of early nonspecific resistance.

Animals↗
PubMed1984

Opsonic activity of immunoglobulin prepared for intravenous use.

The opsonic activity of two immunoglobulin preparations modified for intravenous infusion was tested against Streptococcus pneumoniae types 3, 7F, and 14 and two strains of Staphylococcus aureus by polymorphonuclear leukocyte uptake of 3H-thymidine-labeled bacteria. Reduced and alkylated immunoglobulin (Chem-IgG) and immunoglobulin prepared by chromatography with diethylaminoethyl-Sephadex (DEAE-IgG) were evaluated with and without complement and compared with the opsonic activity of immune serum globulin and heated pooled human serum. Opsonic activity of DEAE-IgG was greater than that of Chem-IgG and equivalent to the activity of immune serum globulin and pooled human serum against S. aureus 502A and type 3 pneumococcus. Both intravenous immunoglobulins had lower opsonic activity than either pooled human serum or immune serum globulin against type 14 pneumococcus. There were no differences in antibody avidity for pneumococcal antigen among the immunoglobulins tested. All four opsonins had similar opsonic activity against the protein A-deficient S. aureus Wood 46. Modification of immunoglobulin for intravenous infusion by chemical alteration may adversely affect opsonic activity by changing the Fc portion of the antibody molecule.

Antigens, Bacterial↗
PubMed1978

Trypan blue inhibits complement-mediated phagocytosis by human polymorphonuclear leukocytes.

Trypan blue completely inhibited attachment of human polymorphonuclear leukocytes (PMN) to Sepharose beads coated with C3 ant to sheep erythrocytes coated with IgM plus C3, but it did not inhibit attachment to erythrocytes coated with IgG. These results suggested that trypan blue inhibited C-mediated attachment to PMN membranes. Corroborative studies were performed with a strain of Staphylococcus aureus that requires C but not antibody, for opsonization and that activates the alternative pathway. Trypan blue was not toxic to PMN or bacteria, did nto interfere with immunoglobulin or C interactions, and did not affect attachment of opsonins to bacteria. However, the dye impaired PMN killing of S. aureus in normal nonimmune serum by inhibiting bacterial attachment to and ingestion by PMN. Further evidence that the inhibition was at the C3 receptor level came from the observations that, 1) once staphylococci were attached to PMN at either 37 degrees C or 0 degrees C, addition of trypan blue did not inhibit killing; and 2) trypan blue inhibited killing of bacteria opsonized with serum sufficient in C but previously absorbed at 0 degrees C with the same strain of organism to deplete specific antibody. Further studies with this agent may elucidate the roles of opsonic receptors on human phagocytes.

Cell Adhesion↗
PubMed1984

Binding of C-reactive protein to the pneumococcal capsule or cell wall results in differential localization of C3 and stimulation of phagocytosis.

C-reactive protein (CRP) is a serum protein that shows rapid increases of as much as 1000-fold in concentration in response to infection, traumatic injury, or inflammation. CRP reacts with the phosphocholine moiety of pneumococcal cell wall C-polysaccharide, and this reaction can lead to complement activation in vitro and protection against pneumococcal infection in vivo. We have previously studied the chemiluminescence response of human neutrophils to Streptococcus pneumoniae as a measure of in vitro opsonophagocytosis by CRP and complement. CRP in the presence of complement was an effective opsonin for S. pneumoniae serotype 27 (Pn27), but not for serotypes 3 or 6. Because Pn27 differs from most serotypes of S. pneumoniae in containing phosphocholine in its capsular polysaccharide, we have determined the sites of CRP and C3 fixation to Pn27 and S. pneumoniae serotype 4 (Pn4), and related these to the ability of CRP and complement to opsonize these serotypes in vitro. By using a chemiluminescence (CL) assay to measure opsonophagocytosis, CRP was shown to enhance the response of human neutrophils and monocytes to Pn27 in the presence of normal human serum. The CL response of neutrophils and monocytes to Pn4 was not affected by the addition of CRP to serum. The addition of anti-capsular antibody to Pn4 and Pn27 enhanced the CL responses of both neutrophils and monocytes to both bacteria. The localization of bound CRP and C3 on Pn4 and Pn27 was determined by immunoelectron microscopy. CRP bound to Pn4 only in the cell wall region and C3 was located in this area whether or not CRP was present. Anti-capsular antibody deposited C3 in the capsule of Pn4. In contrast, Pn27 bound CRP throughout the capsule and cell wall areas. C3 was deposited in the cell wall region of Pn27 by serum alone and in the cell wall region and capsule when CRP or anti-capsular antibody was present. Because C3 fixation to the capsule was consistently associated with enhanced responses by phagocytic cells, it appears that the site of CRP binding and subsequent complement activation may be critical in the opsonophagocytosis of S. pneumoniae. These findings extend the correlation between capsular C3 and opsonization to a nonimmune system. By using CRP and different pneumococcal serotypes we have shown that the same molecules that are effective in the stimulation of phagocytic cells when bound to the capsule are not effective when bound to the cell wall.

Animals↗
PubMed1982

[The biological importance of C-reactive proteins in non-specific defense mechanisms].

The C-reactive serum protein (CRP) is a classical acute-phase reactant of increasing diagnostical value in clinical practice. It is drastically elevated during reactions of inflammation and tissue destruction, and it binds selectively to necrotic cells of inflamed tissue. The phylogenetically rather ancient protein displays a cyclic pentameric symmetry (pentraxin). CRP undergoes specific binding to phosphocholine esters, polycations and galactans (lectin character). Aggregated CRP activates complement, has opsonin properties and interacts with lymphocytes and thrombocytes. Probably CRP is part of an early unspecific protective mechanism, whereby potentially toxic materials can be detected and eliminated.

Animals↗
PubMed1980

Defective opsonization in multiple myeloma.

The mechanisms responsible for the unusual susceptibility of multiple myeloma (MM) patients to infections are incompletely defined. Since MM is associated with decreased production of normal serum proteins, we investigated the possibility that the production of opsonins might also be impaired. The neutrophil chemiluminescence assay of opsonization was used to evaluate the ability of serum from patients with MM to opsonize zymosan. It was found that sera from 18 MM patients exerted only 50% +/- 2.5% (mean +/- SEM) of the opsonic activity found in 18 control sera (p less than 0.001). In mixture experiments, untreated normal serum completely restored the opsonic activity of MM serum, suggesting a deficiency of opsonic factors rather than an inhibitor. In other mixture experiments, heat-inactivated normal serum only partially corrected the opsonic defect in MM serum. Serum from three patients had low C3 levels, and treatment of particles with these resulted in a greater opsonic defect than the patient population as a whole (p less than 0.02). No correlation between the opsonic defect and infections was established over an 18-mo period. These data suggest that MM serum lacks both heat-stable and heat-labile opsonic activity, the direct clinical significance of which remains to be clarified. However, these studies support the concept that defective host resistance in MM may be multifactoral, combining opsonic abnormalities with other defects previously described.

Complement C3↗
PubMed1983

Effect of erythrocyte stroma on reticuloendothelial system phagocytic function.

Previous studies have demonstrated that intravenous administration of erythrocyte stroma is followed by a depression of RES phagocytic function. The present study evaluated the possibility that depression of hepatic blood flow, activation of the coagulation system, or depletion of opsonic factors mediates the RES depression induced by erythrocyte stroma. Stroma was prepared from washed rat erythrocytes and injected into rats at doses of 0.3, 0.5, 0.75, and 1.0 ml/100 gm. RES depression increased progressively after stroma doses greater than 0.3 ml/100 gm. Hepatic blood flow was decreased only after the 1.0 ml/100 gm dose. Fibrinogen levels were decreased with the 1.0 ml/100 gm dose but were unchanged with the 0.5 ml/100 gm dose of stroma, and the RES depression induced by the 0.5 ml/100 gm dose was not modified by the administration of heparin. Circulating fibronectin levels were not consistently depressed after stroma injection, and in vitro incubation of stroma with serum did not affect fibronectin levels. Erythrocyte stroma decreased hemolytic complement levels but depletion of complement with purified cobra venom factor did not depress RES phagocytic function. Preopsonization of the RES test particle did not modify the stroma-induced RES depression. These results indicate that decreased hepatic blood flow, activation of the coagulation system, or depletion of opsonins did not contribute to the RES depression induced by the 0.5 ml/100 gm dose of stroma. These results suggest that impairment of phagocytic cell function may mediate the effect of erythrocyte debris on RES phagocytic function.

Animals↗
PubMedDate not supplied

Pseudomonas respiratory infection in cystic fibrosis: a possible defect in opsonic IgG antibody?

Chronic Pseudomonas aeruginosa infections of the respiratory tract of people with cystic fibrosis (CF) usually are impossible to eradicate and greatly influence their health and longevity. General mechanisms of host defense are not impaired in this disease, except that serum does not support optimal phagocytosis of pseudomonas bacteria by alveolar macrophages and lung ciliary clearance is diminished, perhaps because of the accumulation of tenacious, purulent secretions in bronchiectatic airways and not by a defect in cilia structure or inhibitors of ciliary function. To investigate the defect in phagocytosis, we postulated that opsonic antibody might not be functioning well. Samples of purified IgG antibody against the typical strain of mucoid pseudomonas were prepared on immunoadsorbents, using CF sera and normal sera from volunteers previously immunized with a pseudomonas vaccine. CF IgG opsonin was found to agglutinate and coat well pseudomonas, but not to adhere or attach well to the surface of human alveolar macrophages, hence a defect in the function of the Fc portion of IgG was noted. In extending this analysis to CF lung secretions obtained by bronchoalveolar lavage, IgG antibody was purified exactly as from serum. Although this IgG had good agglutinating activity, much of it was fragmented (5 S size) and found to lack its Fc portion. It was evident that proteolytic enzymes in the purulent lavage secretions could cleave IgG. This activity was localized to a metallo-proteinase elaborated by the mucoid strain of pseudomonas. Thus, CF IgG may have reduced opsonic antibody function because of a molecular change in the Fc portion; this defect is magnified in the infected CF lung where a bacterial protease can actually fragment IgG and further impair its opsonic activity which is already marginal.

Cystic Fibrosis↗
PubMed1980

[Studies on an extract from Haemophilus influenzae type a. II.--Phagocytic capacity of sera obtained from rabbits immunized by this bacterial extract (author's transl)].

Opsonins may protect against infections. In this study, the different parameters of opsonization assay are strictly standardized. Results are expressed as percentage of opsonization. 0% and 100% opsonization must be established. The experiment without immunserum is used as the 0% opsonization. To determine the 100% opsonization an excess of reducing capacity is required. This is provided by crushed leukocytes. Rabbits are immunised by bacterial extract from Haemophilus influenzae type a. The hemagglutinins are detected in sera earlier (D + 30) and longer than the opsonic activity. Phagocytosis increases from the second month following the immunization. Percentage of opsonization is maintained at about 50% up to the sixth month. Alternatively, the percentage of phagocytosis is decreasing when heterologous bacteria are used. The serum thermolabile factors are necessary for the response. The phagocytic capacity is not modified whether leukocytes are obtained from immunized rabbits or not.

Animals↗
PubMed1980

Insect erythrocyte agglutinins. In vitro opsonization experiments with Clitumnus extradentatus and Periplaneta americana haemocytes.

The effect of naturally occurring haemagglutinins on the in vitro phagocytosis of sheep erythrocytes by the blood cells (haemocytes) of Clitumnus extradentatus and Periplaneta americana was studied. The results showed that the haemagglutinins in both species failed to act as opsonins. Indeed, in some instances, incubation of erythrocytes in haemolymph resulted in less avid ingestion as compared with the saline-incubated controls. This reduced phagocytosis was probably caused by the clumping of erythrocytes on the haemocyte monolayers, leaving fewer single red cells available for uptake. The possible roles of these erythrocyte agglutinins in the host defence systems of insects are discussed.

Animals↗
PubMed1980

Influence of methylprednisolone on reticuloendothelial phagocytic and opsonic function during traumatic and septic shock.

Previous studies have indicated that resistance to shock is closely related to the phagocytic activity of the reticuloendothelial system (RES). The present study examined the possibility that steroid treatment during shock might alter RES activity. RES phagocytic function was assessed by blood clearance and organ localization of gelatinized lipid colloid; opsonin activity by in vitro bioassay; serum concentration of the opsonic alpha 2-SB-glycoprotein (cold-insoluble globulin or fibronectin) by electroimmunoassay; and hepatic sinusoidal blood flow by the fractional clearance technique. Traumatic shock was induced in anesthetized male rats in a Noble-Collip drum while septic shock developed following cecal ligation and puncture. Both shock groups demonstrated depressed RE clearance function in association with diminished hepatic colloid localization and hepatic blood flow and augmented extrahepatic colloid uptake. The injection of methylprednisolone produced no further alterations in these parameters. Steroid injection resulted in enhancement of circulating opsonic activity in all groups compared to vehicle injection. The increased activity was not accompanied by increased levels of immunoreactive opsonic protein, nor could biological activity be enhanced by addition of steroid to plasma in vitro. It is suggested that the steroid acted either to preserve or to enhance the activity of the circulating protein. The relation of this finding to the suggested beneficial effects of steroids in shock remains unresolved.

Animals↗
PubMed1982

[Sensible immunologic diagnosis and therapy in children with recurrent infections].

This retrospective study of immunological findings in 108 children with various infections shows that the majority of patients were younger than 6 years of age. In the main, the study resulted in the following immunological findings. In children with recurrent infections of the lower respiratory tract, there was the notable selective IgA deficiency, much more common than in the rest of the population. Children with otitis and pyogenic infections of the skin, which are mainly bacterial infections, had in particular a low number of anti-bacterial antibodies and were lacking in opsonins. This missing opsonization was significantly higher (p greater than 0,05) in children with recurrent otitis than in the other patients. Anti-bacterial antibodies and osponization of bacteria are only present in effective numbers from the age of about 3 in 90% of healthy children. Patients over 3 with various recurring infections had, in comparison to healthy children, significantly higher numbers a reduced ability to opsonize (p less than 0,00001) or a lack of antibodies (p less than 0,05). These deficiencies occurred separately. Children with infections of the upper respiratory tract or polytope infections had no characteristic deficiencies. In children with a recurring tendency to infection, there are 3 important factors to consider for a meaningful diagnosis and therapy: age, type of illness and the epidemiological situation of the child. If these factors are taken into consideration, the decision as to whether, when and what kind of an immunological test should be carried, is facilitated. The therapy is then also more effective and more selective.

Adolescent↗
PubMed1982

Complementary immunotherapy in the treatment of chronic osteomyelitis.

The authors present a retrospective study of 492 cases of chronic osteomyelitis treated with active immunotherapy to complement surgical and antibiotic treatment. The systematic application of this treatment, which is based on the use of antistaphylococcal vaccines and/or auto-vaccines resulted in the osteomyelitic process being cured in 80 per cent of cases, with complete closure of the fistulae maintained for at least three years. The authors also report the preliminary results obtained with passive immunotherapy in twenty-six patients with chronic osteomyelitis that had proved resistant to all other forms of treatment. Sero-immunological investigations in these patients revealed a deficiency in the opsonifying capacity of the serum. Treatment with opsonin precursors produced complete recession of symptoms and clinical signs, maintained for at least a year, in 50 per cent of these patients.

Adolescent↗
PubMed1981

Resistance of Pasteurella multocida to rabbit neutrophil phagocytosis and killing.

The susceptibilities of several Pasteurella multocida strains to serum bactericidins and to killing by rabbit polymorphonuclear neutrophils (PMN) were investigated, using in vitro assays. Strain Bunia II (serotype 5,12:E) was killed by both immune and normal rabbit sera containing active complement, and strains R1 (serotype 3,12:A) and 656 (serotype 12:B) were serum resistant. Strain R1 opsonized with immune or normal rabbit serum with complement or with immune antibody alone was phagocytized by neutrophils, and strain 656 was ingested only after opsonization with immune antibody in the presence or absence of complement. Complement alone was ineffective as an opsonin for the last 2 serotypes. Neither isolate was resistant to PMN killing. Growth of strain R1 in subcutaneously implanted chambers in rabbits did not increase the resistance of this organism to PMN. Comparison of phagocytosis and killing of this isolate with 2 virulent rabbit strains of P multocida--strains L-A (serotype 12:A) and 7228 (serotype 14:D)--demonstrated that strain L-A was resistant to destruction by neutrophils, whereas strains 7228 and R1 were killed. Resistance of strain L-A was not associated with the hyaluronic acid capsule.

Animals↗
PubMed1994

Vitronectin, fibronectin, and gp120 antibody enhance macrophage release of TNF-alpha in response to Pneumocystis carinii.

Alveolar macrophages (AMS) initiate inflammation during Pneumocystis carinii pneumonia by releasing cytokines including TNF-alpha. Recent studies suggest that macrophage responses to P. carinii are enhanced by serum opsonization, but the mechanisms of enhancement are not well defined. To determine whether macrophage release of TNF-alpha in response to P. carinii was augmented by immune opsonization, alveolar macrophages obtained from rabbits were cultured with P. carinii that had been opsonized with either nonimmune rabbit serum, immune serum generated against P. carinii, or an affinity-purified polyclonal Ab recognizing the major P. carinii surface Ag gp120. Each experiment also included organisms maintained in media alone (nonopsonized P. carinii). Opsonization of P. carinii with immune serum or gp120 Ab significantly enhanced macrophage TNF-alpha release. Interestingly, however, opsonization with nonimmune serum also increased TNF-alpha response to the organism. Because P. carinii is known to interact with the adhesive glycoproteins, vitronectin (VN) and fibronectin (FN), we hypothesized that they might also augment TNF-alpha release. Opsonization of P. carinii with VN or FN resulted in significant potentiation of macrophage TNF-alpha liberation. We further determined that VN and FN were present in increased quantities in the lower respiratory tract of patients with P. carinii pneumonia compared with normal volunteers. Additionally, VN and FN were demonstrated on the surface of freshly isolated P. carinii organisms by immunoblot analysis. Our study suggests that immune and nonimmune opsonins contribute to host defenses during P. carinii pneumonia by enhancing regional TNF-alpha release in response to the organism.

Animals↗
PubMed1995

Lung macrophage uptake of unopsonized environmental particulates. Role of scavenger-type receptors.

The receptors responsible for avid alveolar macrophage (AM) phagocytosis of unopsonized environmental particulates have not been well defined. This study used flow cytometry to quantitate the effects of a panel of soluble ligands for macrophage adhesion receptors on AM binding of unopsonized environmental dusts (titanium dioxide, TiO2; iron oxide, Fe2O3; alpha-quartz, SiO2; diesel engine exhaust dust) or fluorescent latex beads. Polyanionic ligands of the macrophage scavenger receptor (SR) for acetylated-LDL caused marked inhibition of AM binding of the oxide particles and latex beads (e.g., TiO2 binding; polyinosinic acid (polyl), 10 micrograms/ml: 70.2 +/- 1.5% inhibition, mean +/- SE, n = 11). In contrast, no inhibition was seen with the polyanions heparin and chondroitin sulfate (chond-S), or dextran, consistent with the known inhibitor profile of macrophage SRs for acetylated-LDL AM uptake of latex or SiO2 beads instilled into lungs of hamsters was inhibited by administration of polyl but not chondroitin sulfate (AM beads per cell: control, 6.1 +/- 0.7; polyl, 3.5 +/- 0.2; chond-S, 5.1 +/- 0.7, n > or = 4, p < 0.05 for control vs polyl) indicating macrophages SRs operate in vivo as well as in vitro. In contrast, AM binding of the carbonaceous diesel dust particles was not inhibited by any ligand tested. AM uptake of unopsonized TiO2, SR ligands or acetylated LDL caused no significant activation of AM respiratory burst or TNF production, consistent with past observations that opsonin-independent phagocytosis of inert particles by normal AMs is not accompanied by pro-inflammatory activation. These data implicate macrophage-type SRs in AM binding of charged environmental particles and indicate that distinct mechanisms mediate binding of carbonaceous dusts.

Air Pollutants↗
PubMed1976

Complex surveillance of Streptococcus pyogenes. III. Immunological characteristics of streptococcal resistance in blood and new aspects of type nonspecific protection.

The influence of nonspecific immunity factors in indifferent human blood on the resistance of M non-typable field streptococci and collection M strains in the absence of anti-M antibodies was studied. The experimental results indicate that primary resistance is conditioned on balanced equipment of the strain with M protein and the nonspecific cofactor receptor [R]. Disbalanced strains were strongly phagocytized, with participation by nonspecific opsonins (complement C3 and nonspecific cofactor), irrespective of their M protein content. M + R--disbalance (selected collection strains) and M--R + disbalance (field strains on artificial media) were observed. The M and R resistance factor equipment of the streptococci probably represents plus and minus variants in the diverse process of the asymptomatic dissemination and pathogenic activity of streptococci in the human population. The given results are manifestly related to the general manner of existence of streptococci, to questions of conditional pathogenicity and to the concept of nonspecific defence against streptococci.

Antibody Specificity↗
PubMed1978

Protection against fulminant sepsis in splenectomized mice by implantation of autochthonous splenic tissue.

Infection of splenectomized mice with Diplococcus pneumoniae, type III, resulted in a fourfold higher mortality rate than did infection of normal mice. Splenectomized animals were protected against fulminant, fatal sepsis by subcutaneous transplantation of autochthonous splenic tissue at the time of splenectomy. Animals with ectopic splenic tissue, and sham-splenectomized control mice, exhibited normal serum opsonin and leukophilic gamma-globulin activity, with respect to pneumococcus, that was lacking in splenectomized animals.

Animals↗