scholarly journals PHAGOCYTOSIS OF IMMUNE COMPLEXES BY MACROPHAGES

1972 ◽  
Vol 135 (4) ◽  
pp. 780-792 ◽  
Author(s):  
B. Mantovani ◽  
M. Rabinovitch ◽  
V. Nussenzweig

Sheep red cells (E) sensitized with IgG antibody (EA) or with antibody and complement (EAC) interact in vitro with mouse peritoneal macrophage monolayers. The role of IgG and of C3 in the attachment and ingestion of the erythrocytes was examined by means of quantitative technique utilizing 51Cr-labeled E. Controlled osmotic lysis permitted the separate measurement of the radioactivity associated with bound or with ingested E. IgG-125I was used to estimate the number of IgG molecules bound per E as a function of the IgG concentration. Control experiments showed that iodination did not influence the extent of binding of IgG to E and that the binding of IgG prepared from immune serum could be essentially ascribed to its anti-E antibody content. Only between 103 and 104 rabbit anti-E IgG molecules per erythrocyte were needed for detectable attachment and ingestion of EA (a maximum number of 6 x 105 IgG antibody molecules could be accomodated on one erythrocyte). Evidence was obtained that C3 is primarily involved in particle attachment, whereas only IgG is able to markedly promote the ingestion of particles attached to macrophages: (a) Addition of complement to the EA substantially increased the binding to the macrophages, whereas ingestion was increased to a smaller extent. Both binding and ingestion of EAC were markedly inhibited by papain fragments of IgG obtained from a rabbit antiserum to mouse C3. (b) Low doses (2 µg/ml) of papain fragments of IgG from a rabbit antiserum to mouse IgG markedly reduced the ingestion of EAC, whereas attachment of EAC to macrophages was inhibited to a much smaller degree. The possible relevance of these findings for the in vivo fate of particulate immune complexes as they interact with macrophages is discussed. It is suggested that in the primary immune response, when the complexes are predominantly in the form of EA (IgM) or EA (IgM) C3, they would tend to remain on the surface of the macrophages and thus be in a position to stimulate immunocompetent cells. In the secondary response, when EA (IgG) or EA (IgG) C3 predominate, the complexes would tend to be more rapidly interiorized and degraded by the mononuclear phagocytes,

1942 ◽  
Vol 75 (3) ◽  
pp. 247-268 ◽  
Author(s):  
Max B. Lurie ◽  

1. Mononuclear phagocytes of immunized animals that had ingested tubercle bacilli in vivo and had subsequently been transplanted and grown in the environment of a normal animal continue to inhibit the multiplication of the microorganism in their cytoplasm in the absence of immune body fluids. 2. Mononuclear phagocytes of immunized animals that had ingested tubercle bacilli in vitro in the presence of immune serum inhibit the multiplication of the microorganism in their cytoplasm to a much greater extent than cells of normal animals that had ingested the bacteria in the same medium and had grown in a similar environment. 3. The presence of immune serum during the in vitro ingestion of tubercle bacilli by mononuclear phagocytes of normal animals does not regularly endow them with increased bacteriostatic properties for the microorganism. Whether or not continued sojourn of normal cells in immune body fluids will confer upon them such properties has not been determined. 4. Mononuclear phagocytes of immunized animals that had ingested tubercle bacilli in vitro in a medium of normal serum and had subsequently grown in an environment devoid of immune body fluids inhibit the multiplication of the microorganism in their cytoplasm to a much greater extent than do normal cells under the same conditions. 5. Active tuberculosis confers on the mononuclear phagocytes themselves increased bacteriostatic properties for the tubercle bacillus which are independent of the immune body fluids or of the organ environment in which they grow.


Blood ◽  
1994 ◽  
Vol 83 (9) ◽  
pp. 2516-2525 ◽  
Author(s):  
K Meszaros ◽  
S Aberle ◽  
R Dedrick ◽  
R Machovich ◽  
A Horwitz ◽  
...  

Abstract Mononuclear phagocytes, stimulated by bacterial lipopolysaccharide (LPS), have been implicated in the activation of coagulation in sepsis and endotoxemia. In monocytes LPS induces the synthesis of tissue factor (TF) which, assembled with factor VII, initiates the blood coagulation cascades. In this study we investigated the mechanism of LPS recognition by monocytes, and the consequent expression of TF mRNA and TF activity. We also studied the inhibition of these effects of LPS by rBPI23, a 23-kD recombinant fragment of bactericidal/permeability increasing protein, which has been shown to antagonize LPS in vitro and in vivo. Human peripheral blood mononuclear cells, or monocytes isolated by adherence, were stimulated with Escherichia coli O113 LPS at physiologically relevant concentrations (> or = 10 pg/mL). The effect of LPS was dependent on the presence of the serum protein LBP (lipopolysaccharide-binding protein), as shown by the potentiating effect of human recombinant LBP or serum. Furthermore, recognition of low amounts of LPS by monocytes was also dependent on CD14 receptors, because monoclonal antibodies against CD14 greatly reduced the LPS sensitivity of monocytes in the presence of serum or rLBP. Induction of TF activity and mRNA expression by LPS were inhibited by rBPI23. The expression of tumor necrosis factor showed qualitatively similar changes. Considering the involvement of LPS-induced TF in the potentially lethal intravascular coagulation in sepsis, inhibition of TF induction by rBPI23 may be of therapeutic benefit.


Blood ◽  
1996 ◽  
Vol 87 (5) ◽  
pp. 1862-1872 ◽  
Author(s):  
M Introna ◽  
VV Alles ◽  
M Castellano ◽  
G Picardi ◽  
L De Gioia ◽  
...  

Abstract Pentraxins, which include C reactive protein (CRP) and serum amyloid P component (SAP), are prototypic acute phase reactants that serve as indicators of inflammatory reactions. Here we report genomic and cDNA cloning of mouse ptx3 (mptx3), a member of the pentraxin gene family and characterize its extrahepatic expression in vitro and in vivo. mptx3 is organized into three exons on chromosome 3: the first (43 aa) and second exon (175 aa) code for the signal peptide and for a protein portion with no high similarity to known sequences the third (203 aa) for a domain related to classical pentraxins, which contains the “pentraxin family signature.” Analysis of the N terminal portion predicts a predominantly alpha helical structure, while the pentraxin domain of ptx3 is accommodated comfortably in the tertiary structure fold of SAP. Normal and transformed fibroblasts, undifferentiated and differentiated myoblasts, normal endothelial cells, and mononuclear phagocytes express mptx3 mRNA and release the protein in vitro on exposure to interleukin-1beta (IL-1beta) and tumor necrosis factor (TNF)alpha. mptx3 was induced by bacterial lipopolysaccharide in vivo in a variety of organs and, most strongly, in the vascular endothelium of skeletal muscle and heart. Thus, mptx3 shows a distinct pattern of in vivo expression indicative of a significant role in cardiovascular and inflammatory pathology.


1918 ◽  
Vol 28 (5) ◽  
pp. 571-583
Author(s):  
Julia T. Parker

1. The livers of rabbits inoculated with cultures of Bacillus typhosus or Bacillus prodigiosus under certain conditions contain a toxic substance extractable with salt solution. When the toxic extracts are injected intravenously into normal rabbits the latter animals develop symptoms resembling those of anaphylactic shock and succumb. The lethal doses of the toxic extracts are far smaller than those of normal liver extract. 2. The livers of rabbits injected with typhoid antigen also yield a toxic extract. 3. Boiling as well as filtration through a Berkefeld filter only partially detoxicates the extract. 4. Tolerance to one to two lethal doses of the poisonous extracts can be induced by cautious immunization. 5. Rabbits actively immunized to Bacillus typhosus or Bacillus prodigiosus usually resist one lethal dose of the homologous liver poison; and animals tolerant to the typhoid liver poison resist one minimum lethal dose at least of Bacillus typhosus. 6. Typhoid immune serum is not detoxicating either in vivo or in vitro for the typhoid liver poison. 7. The liver poisons are specific, since rabbits actively immunized to either Bacillus typhosus or Bacillus prodigiosus withstand at least one minimum lethal dose of the homologous but not of the heterologous-liver poisons.


1980 ◽  
Vol 29 (2) ◽  
pp. 575-582
Author(s):  
Robert E. Baughn ◽  
Kenneth S. K. Tung ◽  
Daniel M. Musher

The in vivo and in vitro immunoglobulin G plaque-forming cell responses to sheep erythrocytes (SRBC) are nearly obliterated during disseminated syphilitic infection (3 to 8 weeks post-intravenous injection) in rabbits. Splenic and lymph node cells obtained from infected rabbits during this time period were capable of suppressing the normal in vitro responses of uninfected, SRBC-primed cells. Cell-free washings of cells from infected animals were also suppressive. This finding coupled with the fact that treatment of infected cells with proteolytic enzymes abrogated the suppressive effect constitute arguments against involvement of a specific suppressor cell population. The incidence of elevated levels of circulating immune complexes in the sera of rabbits with disseminated disease was also significantly different from that of uninfected controls or infected rabbits before the onset or after the regression of lesions. When added to cultures of lymphocytes from uninfected, SRBC-sensitized rabbits, sera containing complexes caused dose-related suppression of the in vitro immunoglobulin responses. Unlike immune complexes, no correlation was found between the presence of mucopolysaccharide materials and the stage of infection or the ability of serum to suppress the immunoglobulin responses to SRBC.


2020 ◽  
Author(s):  
Sophia Michelchen ◽  
Burkhard Micheel ◽  
Katja Hanack

AbstractGenerating monoclonal antibodies to date is a time intense process requiring immunization of laboratory animals. The transfer of the humoral immune response into in vitro settings shortens this process and circumvents the necessity of animal immunization. However, orchestrating the complex interplay of immune cells in vitro is very challenging. We aimed for a simplified approach focusing on the protagonist of antibody production: the B lymphocyte. We activated purified murine B lymphocytes in vitro with combinations of antigen and stimuli. Within ten days of culture we induced specific IgM and IgG antibody responses against a viral coat protein. Permanently antibody-producing hybridomas were generated. Furthermore we used this method to induce a specific antibody response against Legionella pneumophila. We thus established an effective protocol to generate monoclonal antibodies in vitro. By overcoming the necessity of in vivo immunization it may be the first step towards a universal strategy to generate antibodies from various species.


1973 ◽  
Vol 137 (2) ◽  
pp. 411-423 ◽  
Author(s):  
John W. Moorhead ◽  
Curla S. Walters ◽  
Henry N. Claman

Both thymus-derived (T) and bone marrow-derived (B) lymphocytes participate in the response to a hapten 4-hydroxy-3-iodo-5-nitrophenylacetic acid (NIP), coupled to a nonimmunogenic isologous carrier, mouse gamma globulin (MGG). Spleen cells from mice immunized with NIP-MGG show increased DNA synthesis in vitro when cultured with NIP-MGG. The participation of and requirement for T cells in the response was demonstrated by treating the spleen cells with anti-θ serum. This treatment resulted in a 77% inhibition of the antigen response. Furthermore, adoptively transferred normal thymus cells could be specifically "activated" by NIP-MGG in vivo and they responded secondarily to the antigen in vitro. The active participation of B cells in the secondary response was demonstrated by passing the immune spleen cells through a column coated with polyvalent anti-MGG serum. Column filtration reduced the number of NIP-specific plaque-forming cells and NIP-specific rosette-forming cells (both functions of B cells) and produced a 47% inhibition of the NIP-MGG response. The ability of the cells to respond to phytohemagglutinin (PHA) was not affected by column filtration showing that T cells were not being selectively removed. The participation of B cells in the in vitro NIP-MGG response was also shown by treatment of the spleen cells with antiserum specific for MGG and MGG determinants. B cells were removed by treatment with anti-IgM or polyvalent anti-MGG serum plus complement, resulting in a respective 46 and 49% inhibition of the response to NIP-MGG. (Treatment with anti-IgM serum had no effect on T cells.) The contribution of the hapten NIP to stimulation of T cells was investigated using NIP-MGG-activated thymus cells. These activated T cells responded in vitro very well to the NIP-MGG complex but not to the MGG carrier alone demonstrating the requirement of the hapten for T cell stimulation. The response was also partially inhibited (41%) by incubating the activated cells with NIP coupled to a single amino acid (epsilon-aminocaproic acid) before addition of NIP-MGG. These results demonstrated that T cells recognize the hapten NIP when it is coupled to the isologous carrier MGG.


1987 ◽  
Author(s):  
J Bussel

ITP is an autoantibody-mediated disease which would logically be treated by decreasing the level of autoantibody. However, the most exciting developments in understanding the pathophysiology of the thrombocytopenia and its treatment involve a better understanding of the MPS FcR system and ways in which it can be modulated. This work has focussed on phagocytic paralysis or FcR blockade (FcRBl): the slowing of destruction of antibody-coated platelets despite the persistent presence of antibody on the surface of the platelet.Several areas have been explored in learning about the MPS system. Investigation by Kurlander among others have revealed that at least 2 FcR's exist on mononuclear phagocytes: one with high and one with low affinity for monomeric IgG. Study of the high affinity FcR expressed by circulating monocytes, by Schreiber among others, has explored the effect of Danazol to decrease the expression of this FcR. The clinical relevance of this receptor is uncertain however because it is saturated in vitro by physiologic concentrations of IgG. Unkeless defined the properties of the low affinity "immune complex" FcR, expressed on macrophages and neutrophils, via monoclonal antibody 3G8 (see below) which blocks ligand binding to this FcR. The exact roles of these two, and possibly more, FcR's are being explored. Another still unsolved controversy involves whether the interaction Fc portions of antibodies coating particles with FcR's is mediated by a conformational change of the Fc portion or by a multipoint attachment of several Fc parts.Studies by Mollison in the 60's demonstrated that the MPS had a limited capacity for removal of antibody-coated (red) cells. Shulman pursued MPS modulation by exploring the inhibition of thrombocytopenia caused by infusion of ITP plasma into normals. Kelton demonstrated that "compensated" ITP may be caused by a decreased clearance of antibody-coated cells and that the rate of clearance of antibody-coated cells may be correlated with rate of clearance of antibody-coated cells may be correlated with the intrinsic levels of IgG. Stossel investigated FcRBl as a mechanism of effect of corticosteroids and related it clinically. Subsequently intravenous gammaglobulin (IVGG) was introducedas a treatment of ITP and Fehr et al first demonstrated FcRBl as the mechanism of effect of IVGG. Exploration of the mechanism of the FcRBl caused by IVGGled Salama and Mueller-Eckhardt to demonstrate the therapeutic effect of I anti-D, which apparentlycoats RBC with antibody and causes their destruction atthe coats RBC with antibody and causes their destruction at the expense of antibody-coated platelets. A similar degree of FcRBl has been shown for aldometrelated to the development of antibody on RBC.Our studies, including Drs. Clarkson, Kimberly, Nachman, and Unkeless, have focussed on the role of the low affinity or "Immune complex" FcR by using monoclonal antibody 3G8 in vivo. An infusion of 1 mg/kg of 3G8 in chimpanzees caused a reproducible FcRBl demonstrable by a slowing of the destruction of antibody-coated RBC for > 10 days (JEM, 1986). Less effect of 3G8 to inhibit CIC removal was seen using DNA-anti-DNA as the immune complex. In view of the wel1-documented effects of IVGG infusion to create FcRBl, we infused 3G8 into 6 adults with refractory ITP (NEJM, 1986). Specifically these patients were refractory to all forms of conventional therapy including splenectomy, steroids, vinca alkaloid infusion, immunosuppressives and danazol . 3 of the 6 patients had peak platelet responses to >80,000/ul. The other 3 had short-lived platelet increases from 10 to 30,000/ul. These responses confirmed the effect of FcRBl, specifically of the low affinity FcR, to underlie a dramatic platelet increase in therapy of ITP. Surprisingly 3 of the patients had apparent longterm effects of this therapy demonstrable in 2 cases as a maintenance of the platelet count >20,0C0/ul without any further therapy and in 1 case as a clearly enhanced responsiveness to other therapies following 3G8 infusion. Since Natural Killer activity was (transiently) ablated by 3G8 infusion, we speculate that an alternation of regulation of (auto) antibody production by NK cells may be responsible for this effect and that FcR interactions include regulatory roles in addition to their primary function of removal of CIC.


Cancers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1420
Author(s):  
Dennis Paul ◽  
Paul Maggi ◽  
Fabio Del Piero ◽  
Steven D. Scahill ◽  
Kelly Jean Sherman ◽  
...  

Concurrent activation of voltage-gated sodium channels (VGSCs) and blockade of Na+ pumps causes a targeted osmotic lysis (TOL) of carcinomas that over-express the VGSCs. Unfortunately, electrical current bypasses tumors or tumor sections because of the variable resistance of the extracellular microenvironment. This study assesses pulsed magnetic fields (PMFs) as a potential source for activating VGSCs to initiate TOL in vitro and in vivo as PMFs are unaffected by nonconductive tissues. In vitro, PMFs (0–80 mT, 10 msec pulses, 15 pps for 10 min) combined with digoxin-lysed (500 nM) MDA-MB-231 breast cancer cells stimulus-dependently. Untreated, stimulation-only, and digoxin-only control cells did not lyse. MCF-10a normal breast cells were also unaffected. MDA-MB-231 cells did not lyse in a Na+-free buffer. In vivo, 30 min of PMF stimulation of MDA-MB-231 xenografts in J/Nu mice or 4T1 homografts in BALB/c mice, concurrently treated with 7 mg/kg digoxin reduced tumor size by 60–100%. Kidney, spleen, skin and muscle from these animals were unaffected. Stimulation-only and digoxin-only controls were similar to untreated tumors. BALB/C mice with 4T1 homografts survived significantly longer than mice in the three control groups. The data presented is evidence that the PMFs to activate VGSCs in TOL provide sufficient energy to lyse highly malignant cells in vitro and to reduce tumor growth of highly malignant grafts and improve host survival in vivo, thus supporting targeted osmotic lysis of cancer as a possible method for treating late-stage carcinomas without compromising noncancerous tissues.


Blood ◽  
1985 ◽  
Vol 65 (6) ◽  
pp. 1391-1395 ◽  
Author(s):  
P Montemurro ◽  
A Lattanzio ◽  
G Chetta ◽  
L Lupo ◽  
L Caputi-Iambrenghi ◽  
...  

Abstract Intralipid, a fat emulsion widely used in parenteral nutrition, can produce marked functional changes of the mononuclear phagocyte system. We investigated the effect of Intralipid administration on the generation of procoagulant activity by rabbit mononuclear phagocytes. Two groups of ten rabbits given either a single infusion of Intralipid 10% or a similar volume of sterile saline were studied before and after infusion. Procoagulant activity was measured on isolated blood mononuclear cells after incubation with and without endotoxin, using a one-stage clotting assay. Cells from animals infused with Intralipid produced significantly more procoagulant activity than controls (P less than .01). Results were similar when freshly collected whole blood was incubated with and without endotoxin, and procoagulant activity was measured on subsequently isolated mononuclear cells (P less than .01). In addition, when rabbits were given a single injection of endotoxin, blood and spleen mononuclear cells harvested 50 to 60 minutes after the injection from animals pretreated with Intralipid expressed five to seven times more procoagulant activity than did cells from animals pretreated with saline. In all instances, procoagulant activity was identified as tissue factor. These findings suggest that Intralipid may cause functional changes in mononuclear phagocytes, resulting in increased production of tissue factor on incubation in short-term culture in vitro and in response to endotoxin in vivo.


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