Role of Immune Complex Size and Complement Binding in Regulating Monocyte Responses to Immune Complexes • 1982

The possibility that immune complexes cause otitis media with effusion (OME) has been previously proposed. In order to test this hypothesis we developed an animal model in which immune complexes were injected into the middle ears of chinchillas and the animals killed at various time intervals thereafter. Moderate inflammatory changes were seen in animals killed four hours postinjection, whereas intense inflammation was observed in those killed at 24 hours. Inflammatory changes observed included capillary dilatation with increased capillary permeability, migration of polymorphonuclear leukocytes into the submucosa, hemorrhage, and damage to and actual disruption of the subepithelial basement membrane. These changes are consistent with a complement-mediated acute inflammatory reaction. Although no definite conclusion can be made concerning the etiologic role of immune complex in OME, our findings show that immune complexes can cause acute inflammatory changes in the middle ear of the experimental animal.

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Apolipoprotein J/Clusterin Prevents a Progressive Glomerulopathy of Aging

Molecular and Cellular Biology ◽

10.1128/mcb.22.6.1893-1902.2002 ◽

2002 ◽

Vol 22 (6) ◽

pp. 1893-1902 ◽

Cited By ~ 74

Author(s):

Mark E. Rosenberg ◽

Richard Girton ◽

David Finkel ◽

David Chmielewski ◽

Arthur Barrie ◽

...

Keyword(s):

Immune Complex ◽

Immune Complexes ◽

Protective Role ◽

Multiple Injury ◽

Wild Type ◽

Apolipoprotein J ◽

Age Dependent ◽

Deficient Mice ◽

Complex Lesions

ABSTRACT Apoliprotein J (apoJ)/clusterin has attracted considerable interest based on its inducibility in multiple injury processes and accumulation at sites of remodeling, regression, and degeneration. We therefore sought to investigate apoJ/clusterin's role in kidney aging, as this may reveal the accumulated effects of diminished protection. Aging mice deficient in apoJ/clusterin developed a progressive glomerulopathy characterized by the deposition of immune complexes in the mesangium. Up to 75% of glomeruli in apoJ/clusterin-deficient mice exhibited moderate to severe mesangial lesions by 21 months of age. Wild-type and hemizygous mice exhibited little or no glomerular pathology. In the apoJ/clusterin-deficient mice, immune complexes of immunoglobulin G (IgG), IgM, IgA, and in some cases C1q, C3, and C9 were detectable as early as 4 weeks of age. Electron microscopy revealed the accumulation of electron-dense material in the mesangial matrix and age-dependent formation of intramesangial tubulo-fibrillary structures. Even the most extensively damaged glomeruli showed no evidence of inflammation or necrosis. In young apoJ/clusterin-deficient animals, the development of immune complex lesions was accelerated by unilateral nephrectomy-induced hyperfiltration. Injected immune complexes localized to the mesangium of apoJ/clusterin-deficient but not wild-type mice. These results establish a protective role of apoJ/clusterin against chronic glomerular kidney disease and support the hypothesis that apoJ/clusterin modifies immune complex metabolism and disposal.

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Pseudomonas syringae effector HopZ3 suppresses the bacterial AvrPto1–tomato PTO immune complex via acetylation

PLoS Pathogens ◽

10.1371/journal.ppat.1010017 ◽

2021 ◽

Vol 17 (11) ◽

pp. e1010017

Author(s):

Joanna Jeleńska ◽

Jiyoung Lee ◽

Andrew J. Manning ◽

Donald J. Wolfgeher ◽

Youngjoo Ahn ◽

...

Keyword(s):

Immune Complex ◽

Pseudomonas Syringae ◽

Immune Complexes ◽

Site Directed Mutagenesis ◽

Host Proteins ◽

Susceptibility To Infection ◽

Binding Interface ◽

Lysine Residues ◽

Increased Susceptibility

The plant pathogen Pseudomonas syringae secretes multiple effectors that modulate plant defenses. Some effectors trigger defenses due to specific recognition by plant immune complexes, whereas others can suppress the resulting immune responses. The HopZ3 effector of P. syringae pv. syringae B728a (PsyB728a) is an acetyltransferase that modifies not only components of plant immune complexes, but also the Psy effectors that activate these complexes. In Arabidopsis, HopZ3 acetylates the host RPM1 complex and the Psy effectors AvrRpm1 and AvrB3. This study focuses on the role of HopZ3 during tomato infection. In Psy-resistant tomato, the main immune complex includes PRF and PTO, a RIPK-family kinase that recognizes the AvrPto effector. HopZ3 acts as a virulence factor on tomato by suppressing AvrPto1Psy-triggered immunity. HopZ3 acetylates AvrPto1Psy and the host proteins PTO, SlRIPK and SlRIN4s. Biochemical reconstruction and site-directed mutagenesis experiments suggest that acetylation acts in multiple ways to suppress immune signaling in tomato. First, acetylation disrupts the critical AvrPto1Psy-PTO interaction needed to initiate the immune response. Unmodified residues at the binding interface of both proteins and at other residues needed for binding are acetylated. Second, acetylation occurs at residues important for AvrPto1Psy function but not for binding to PTO. Finally, acetylation reduces specific phosphorylations needed for promoting the immune-inducing activity of HopZ3’s targets such as AvrPto1Psy and PTO. In some cases, acetylation competes with phosphorylation. HopZ3-mediated acetylation suppresses the kinase activity of SlRIPK and the phosphorylation of its SlRIN4 substrate previously implicated in PTO-signaling. Thus, HopZ3 disrupts the functions of multiple immune components and the effectors that trigger them, leading to increased susceptibility to infection. Finally, mass spectrometry used to map specific acetylated residues confirmed HopZ3’s unusual capacity to modify histidine in addition to serine, threonine and lysine residues.

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Experimental Amyloidosis Induced by Immune Complex

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066978 ◽

1971 ◽

Vol 29 ◽

pp. 582-583

Author(s):

A. Kawaoi

Keyword(s):

Immune Complex ◽

Systemic Amyloidosis ◽

Human Diseases ◽

Experimental Amyloidosis ◽

Freund’S Complete Adjuvant ◽

Freund's Complete Adjuvant ◽

Immunological Approach ◽

Experimentally Induced

Numbers of immunological approach have been made to the amyloidosis through the variety of predisposing human diseases and the experimentally induced animals by the greater number of agents. The results suggest an important role of impaired immunity involving both humoral and cell-mediated aspects.Recently the author has succeeded in producing amyloidosis in the rabbits and mice by the injections of immune complex of heat denatured DNA.The aim of this report is to demonstrate the details of the ultrastructure of the amyloidosis induced by heterologous insoluble immune complex. Eleven of twelve mice, dd strain, subcutaneously injected twice a week with Freund's complete adjuvant and four of seven animals intraperitonially injected developed systemic amyloidosis two months later from the initial injections. The spleens were electron microscopically observed.

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Localization of Immune Complexes in the Basement Membrane of the Ductuli Efferentes of the Rhesus Monkey

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001963 ◽

1980 ◽

Vol 38 ◽

pp. 456-457

Author(s):

D. Marsh

Keyword(s):

Basement Membrane ◽

Fluorescence Microscopy ◽

Rhesus Monkey ◽

Immune Complex ◽

Immune Complexes ◽

Vas Deferens ◽

Frozen Sections ◽

Efferent Ducts ◽

Complex Deposition ◽

Sperm Antibodies

As a result of vasectomy, spermatozoa are confined to the epididymis and vas deferens, where they degenerate, releasing antigens that enter the circulation or are engulfed by macrophages. Multiple antigens of the sperm can elicit production of autoantibodies; circulating anti-sperm antibodies are found in a large percentage of vasectomized men, indicating the immunogenicity of the sperm. The increased prevalence of macrophages in the liomen of the rhesus monkey testicular efferent ducts after vasectomy led to further study of this region. Frozen sections were used for evaluation of immunopathological status by fluorescence microscopy with fluorescein-conjugated antibody. Subsequent granular deposits of immune complexes were revealed by positive immunofluorescence staining for complement. The immune complex deposition in the basement membrane surrounding the efferent ducts implies that this region is involved in antigen leakage (Fig. 1).

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Role of Circulating Immune Complexes in the Pathogenesis of Canine Leishmaniasis: New Players in Vaccine Development

Microorganisms ◽

10.3390/microorganisms9040712 ◽

2021 ◽

Vol 9 (4) ◽

pp. 712

Author(s):

Cristina Cacheiro-Llaguno ◽

Nuria Parody ◽

Marta R. Escutia ◽

Jerónimo Carnés

Keyword(s):

Immune Complexes ◽

Vaccine Development ◽

Correct Diagnosis ◽

Circulating Immune Complexes ◽

Response To Treatment ◽

Canine Leishmaniasis ◽

Leishmania Infection ◽

Serum Samples ◽

Humoral Immune

During canine visceral leishmaniasis (CanL), due to Leishmania infantum (L. infantum), uncontrolled infection leads to a strong humoral immune response. As a consequence of the production of high antibody levels and the prolonged presence of parasite antigens, circulating immune complexes (CIC) are formed, which can be deposited in certain organs and tissues, inducing vasculitis, uveitis, dermatitis and especially glomerulonephritis and renal failure. A method to detect CIC and quantify their levels in serum samples from dogs infected with L. infantum has been recently described. It allowed demonstration of a correlation between CIC levels and disease severity. Thus, CIC measurement may be useful for diagnosis, assessment of disease progression and monitoring response to treatment. This is an interesting finding, considering that there remains an urgent need for identification of novel biomarkers to achieve a correct diagnosis and for optimal disease staging of dogs suffering from Leishmania infection. The objective of the present review is to shed light on the role of CIC in CanL, as well as to highlight their potential use not only as diagnostic and prognostic biomarkers but also as a valuable tool in vaccine development and new immunotherapy strategies to prevent or control disease outcome.

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Evaluation of Serum Immunoglobulins (IgG, IgA, IgM) and Circulating Immune Complexes in Oral Precancer and Cancer Patients

Global Medical Genetics ◽

10.1055/s-0041-1725157 ◽

2021 ◽

Author(s):

Pooja Madki ◽

Mandya Lakshman Avinash Tejasvi ◽

Geetha Paramkusam ◽

Ruheena Khan ◽

Shilpa J.

Keyword(s):

Oral Cancer ◽

Immune Complexes ◽

Serum Levels ◽

Circulating Immune Complexes ◽

Oral Cancers ◽

Cancer Group ◽

Oral Precancer ◽

Serum Iga ◽

The Mean

Abstract Objectives The aim of the present study is to evaluate the role of immunoglobulins (IgA, IgG, and IgM) and circulating immune complexes (CIC) as tumor marker in oral cancer and precancer patients. Materials and Methods The present study was performed on 45 individuals subdivided into three groups, that is, oral precancer, oral cancer and healthy individuals, and levels of immunoglobulins, and CIC was estimated by turbidometry and ELISA method. Results In the present study, the mean serum IgA levels in oral precancer were 161.00 ( ± 118.02) mg/dL, oral cancers were 270.67 ( ± 171.44) mg/dL, and controls were 133.73 ( ± 101.31) mg/dL. Mean serum levels of IgG in oral precancer were 1,430.87 ( ± 316) mg/dL, oral cancers were 1,234.27 ( ± 365.42) mg/dL, and controls were 593.87 ( ± 323.06) mg/dL. Conclusion We found that the levels of serum IgG and IgA were elevated consistently in precancer and cancer group, and Serum IgM levels were increased only in precancer. Also, significant increase in serum CIC levels were seen in oral precancer and cancer group on comparison with control.

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