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PubMed1982

Direct immunofluorescence in oral lichen planus.

Direct immunofluorescent staining (DIF) was performed on biopsy specimens from thirty-five patients with oral lichen planus. The results showed fibrin deposition in all cases at the mucosal-submucosal interface, within colloid bodies (fourteen of thirty-five) and within vascular walls (five of thirty-five). Deposition of IgG, IgA and IgM was detected to a lesser extent, while complement (C3) could not be identified in any case. The significance of these findings was assessed by comparison with the IF results obtained in thirty-five biopsies from various oral diseases other than lichen planus and ten healty persons. Although the presence of fibrin deposition at the mucosal-submucosal junction, within vessels and cytoid bodies, was found to be highly characteristic of lichen planus, these findings were not specifically diagnostic. Morphologically identical deposits were also seen in lupus erythematosus. It is known at present whether immunologic reactions may play a role in the pathogenesis of lichen planus. However, the immunopathologic findings may occasionally be additional suggestive markers in the diagnosis of the disease.

Complement C3↗

PubMed1984

Renal histopathology in the hemolytic-uremic syndrome following shigellosis.

The hemolytic-uremic syndrome (HUS) following dysentery caused by S. dysenteriae Type 1, characterized by microangiopathic hemolytic anemia and acute renal insufficiency, is clinically similar but not identical to the idiopathic HUS. We studied renal necropsy specimens of nine children who died of HUS following shigellosis by light and immunofluorescent microscopy and compared them to 12 controls: six cases with severe shigellosis without HUS, and six with pneumonia or sepsis. Eight of nine HUS cases showed cortical necrosis, extensive glomerular thrombosis or arterial thrombosis. Cases without HUS showed only scattered glomerular fibrin thrombin and widening of the mesangium. Among seven HUS cases studied by immunofluorescent microscopy, three demonstrated deposition of glomerular IgM and complement (C3) and one of the three had IgG and IgA as well; four cases had neither immunoglobulin or complement deposits. Among nine controls, two demonstrated IgM and three IgG, but none had C3. Both HUS and non-HUS cases had fibrin deposition. In the three HUS cases studied by electron microscopy intracapillary material (fibrin and platelets) was seen in all three, and sparse electron-dense deposits in mesangial matrix in one. The data indicate that the renal histopathology in the HUS following shigellosis consistently presents as a severe thrombotic microangiopathy, but lacks the characteristic endothelial and mesangial lesions of idiopathic HUS. The infrequent demonstration of glomerular immunoglobulin deposition fails to support an immunoglobulin-mediated pathogenesis.

Anemia, Hemolytic↗

PubMed2006

Warm ischemia-induced alterations in oxidative and inflammatory proteins in hepatic Kupffer cells in rats.

The aim of the study was to investigate the impact of ischemia/reperfusion injury on the proteome of Kupffer cells. Lean Zucker rats (n = 6 each group) were randomized to 75 min of warm ischemia or sham operation. After reperfusion for 8 h, Kupffer cells were isolated by enzymatic perfusion and density gradient centrifugation. Proteins were tryptically digested into peptides and differentially labeled with iTRAQ (isobaric tags for relative and absolute quantitation) reagent. After fractionation by cation exchange chromatography, peptides were identified by mass spectrometry (ESI-LC-MS/MS). Spectra were interrogated against the Swiss-Prot database and quantified using ProteinProspector. The results for heat shock protein 70 and myeloperoxidase were validated by ELISA. Quantitative information for more than 1559 proteins was obtained. In the ischemia group proteins involved in inflammation were significantly up-regulated. The ratio for calgranulin B in the ischemia/sham group was 1.81 +/- 0.97 (p < 0.0001), for complement C3 the ratio was 1.81 +/- 0.49 (p < 0.0001), and for myeloperoxidase the ratio was 1.30 +/- 0.32. Myeloperoxidase was only recently documented in Kupffer cells. The antioxidative proteins Cu,Zn-superoxide dismutase (1.34 +/- 0.19; p < 0.001) and catalase (1.23 +/- 0.43; p < 0.001) were also elevated. In conclusion, ischemia/reperfusion injury induces alterations in the Kupffer cell proteome. Isotope ratio mass spectrometry is a powerful tool to investigate these reactions. The ability to simultaneously monitor several pathways involved in reperfusion stress may result in important mechanistic insight and possibly new treatment options.

Animals↗

PubMedDate not supplied

Serum protein polymorphism in Papua New Guinea Eastern Highlands.

Four protein polymorphisms: haptoglobin (HP), group specific component (GC), third component of complement (C3) and transferrin (TF), were investigated in Baruya tribes and several other Anga tribes living high in the Wonenara and Marawaka valleys in Papua New Guinea Eastern Highlands. A non-Anga tribe, the Aziana or Kenaze was also sampled. TF*D variant was identified in every group except Usarumpia. A number of anhaptoglobinaemic individuals was noticed. Environmental factors causing hemolysis and haptoglobin consumption are suggested. HP*1 and GC*1 frequencies were high, as usually observed in New Guinea. The Anga tribes are protected from malaria and represent a model of human isolates. The present study confirms this situation.

Black People↗

PubMed1998

Echinococcus granulosus: an intraperitoneal diffusion chamber model of secondary infection in mice.

The present work describes a new experimental model of secondary infection which allows, through the recovery of the parasite together with its local in vivo environment, examination of the local nonadaptive immune response of the infected host and the differentiation of the parasite from protoscoleces to cysts. In this model we administered protoscoleces within silicone diffusion chambers, previously implanted into the peritoneal cavities of mice. The process of designing the model involved, first, determination of the optimal time postimplantation to infect the mice and, second, evaluation of the parasite's ability to establish infection within the chambers. The optimal time for infection was considered to be after the inflammation caused by implantation of the chambers had subsided. Our results showed that by day 20 postsurgery, three parameters used as indications of inflammation (complement C3, serum amyloid P protein, and polymorphonuclear cells in the peritoneum and in the chamber contents) had reverted to their normal levels. In our study of parasite differentiation, we found that 2-3% of the total number of parasites inoculated into the chambers were recovered as viable cysts after 100 days. Throughout the infection period, the population of parasites recovered was heterogeneous; certain parasite morphologies that have not been described previously were observed. In conclusion, the use of intraperitoneal diffusion chambers offers a potential tool for investigating the in vivo differentiation process of secondary cysts of Echinococcus granulosus in mice and the early local interactions between host and parasite during this process.

Animals↗

PubMed2001

Human immunodeficiency virus type 1 Tat binds to Candida albicans, inducing hyphae but augmenting phagocytosis in vitro.

Tat, the human immunodeficiency virus type 1 (HIV-1) transactivating protein, binds through its RGD-motif to human integrin receptors. Candida albicans, the commonest cause of mucosal candidiasis in subjects infected with HIV-1, also possesses RGD-binding capacity. The present study reveals that Tat binds to C. albicans but not to C. tropicalis. Tat binding was markedly reduced by laminin and to a lesser extent by a complement C3 peptide containing the RGD motif, but not by a control peptide. The outgrowth of C. albicans was accelerated following binding of Tat, but phagocytosis of opsonized C. albicans was also increased after Tat binding. Thus, Tat binding promotes fungal virulence by inducing hyphae but may also reduce it by augmenting phagocytosis. The net effect of Tat in vivo is difficult to judge but in view of the many disease-promoting effects of Tat we propose that accelerating the formation of hyphae dominates over the augmentation of phagocytosis.

ATPases Associated with Diverse Cellular Activitie↗

PubMed1984

Genetic markers in renal adenocarcinoma.

The distribution of phenotypes and gene frequencies of the 3rd component of complement (C3), group-specific component (Gc), haptoglobin (Hp) and transferrin (Tf) were studied in 50 patients with renal adenocarcinoma. The statistical analysis of our findings in comparison to the frequency of these genes in the general population does not reveal any correlation between the distribution of the Hp and Tf phenotypes and the disease. On the contrary, a statistically significant association was found between renal adenocarcinoma and C3F and Gc2 genes. The relative risk incidence of this malignancy is 2.07 and 1.94 respectively for the carriers of these genes. These data indicate that genetic factors, possibly related to the immune mechanisms and calcium metabolism, play a role in the pathogenesis of renal adenocarcinoma.

Adenocarcinoma↗

PubMed1993

Biochemical and morphological alterations of macrophages and spleen cells produced by antitumor polysaccharide from Acanthopanax obovatus roots.

Acanthopanax obovatus polysaccharide (AOPS) administrated intraperitoneally (i.p.) resulted in the augmentation of phagocytosis and the chemiluminescence in peritoneal macrophages of mice. Binding of the third component of complement (C3) cleavage products to the receptors on peritoneal macrophages was enhanced by AOPS. The C3 conversion in human serum was increased by AOPS in vitro treatment. When given i.p., AOPS led to the enhancement of spleen weight, spleen cell number, and plaque-forming cells. It was also found that after in vivo administration AOPS not only enhanced the synthesis of DNA and protein but also promoted the mitogenic responses of spleen cells. The morphological observation of spleens indicated that AOPS augmented the transformation from lymphocytes to plasma cells. AOPS inhibited the growth of mouse solid Sarcoma-180 and prolonged the survival time significantly. These results suggest that AOPS is an effective biological response modifier and its antitumor activity is related to its immunopotentiating effects.

Animals↗

PubMed1989

[Various immune functions (with particular attention to NK cells) in young people with frequent episodes of pharyngitis].

In four girls, selected during three years of ambulatory observations, the evolution of repeated upper respiratory tract infection events, under the immunologic aspect, has been studied. The group of girls, with age between 13 and 16 years, practically formed a small casuistry, as an experimental recruitment. With the aim to find the causes of the told infectious events, firstly were checked numerous immune functions, successively were evaluated only the ones that had resulted altered (percentage number of "NK" cells, complement "C3" fraction and "T4" lymphocytes). Particularly significative variations, toward diminution, of the "NK" cells number related to the most compelling school attendance periods were recognized. What observed could let hypothesize that stress and emotions , correlated to scholastic events negatively influence some immune functions, peculiarly the number of "NK" cells. To the lowering of these cells could correspond a facilitation and higher frequency of upper respiratory tract infections (with pharynx as an epicenter), likely by viral aetiology. The subsequent vicarious and/or compensatory intervention by other immune functions could allow, however, the spontaneous recovery, without chemotherapeutic recourse, of the infectious events, that could arise with higher frequency but, most likely, with lower seriousness than could happen when "NK" cells normally act.

Adolescent↗

PubMed1980

Demonstration of an antibody to tubular epithelium in glomerulonephritis associated with obstructive uropathy.

It has been postulated that in some patients with obstructive and reflux uropathy proteinuria develops through an intermediate mechanism of immune complex glomerulonephritis involving antigenic material of renal tubular epithelium. A patient with a unilateral ureterocele and nephrotic syndrome underwent bilateral renal biopsies during surgical correction of the obstruction. The obstructed kidney showed mild pyelonephritis, but both kidneys showed a glomerulopathy with electron-dense deposits in the mesangial and paramesangial regions associated with positive immunofluorescence for immunoglobulin M (IgM) and the third component of complement (C3). An IgM antibody was eluted from the biopsy specimens and it reacted by indirect immunofluorescence with normal renal tubular epithelium and with the patient's renal tubular epithelium. The eluate also reacted with pre-eluted glomeruli of the patient, but not with normal glomeruli. All antibody activity could be removed from the eluate by pre-incubation with normal kidney. It is concluded that the unilateral renal obstruction produced tubular injury so that as yet unidentified antigens were recognized by the immune system. The resultant antibody response gave rise to circulating immune complexes which were then deposited in glomeruli with subsequent glomerular damage and nephrotic syndrome.

Adult↗

PubMed1984

The acute phase response in parasite infection. Nippostrongylus brasiliensis in the mouse.

Systemic inflammatory reactions are a prominent feature of many parasitic infections and the cellular and humoral components of the acute phase reaction may have an impact on the host-parasite relationship. We examined serum changes of four acute phase reactants: alpha 1-proteinase inhibition (alpha 1Pi); complement C3; serum amyloid A protein (SAA); and serum amyloid P component (SAP), in mice undergoing a primary infection with Nippostrongylus brasiliensis. SAA and SAP showed changes within the first 2 days of infection indicating the presence of an acute phase response associated with inflammation in the lung. Alpha 1Pi and C3 serum levels were not altered. However, all four acute phase reactants were synthesized in greater amounts by primary cultures of hepatocytes taken from infected animals at this time. Subsequently, as parasite-mediated inflammatory changes occur in the gut, both serum and hepatocyte cultures demonstrate an acute inflammatory response in all four reactants. It is proposed that the early reaction between parasites and macrophage/monocyte lead to the release of a mediator of inflammation which initiates the hepatocyte response. In this infection, at least one of the APR is shown to localize to the site of inflammation influencing the host-parasite relationship.

Acute Disease↗

PubMed2006

Chronic cicatrizing conjunctivitis in a patient with epidermolysis bullosa acquisita.

OBJECTIVE: To describe a nonconventional diagnostic technique used to diagnose a case of cicatrizing conjunctivitis associated with epidermolysis bullosa acquisita. METHODS: Direct immunofluorescence of a biopsy specimen of the patient's conjunctiva was performed using fluorescein-conjugated rabbit antihuman antibodies against IgA, IgG, and IgM; complement C3; and fibrinogen. Immunoblot assay using healthy human skin as substrate was performed to investigate for the presence of antibodies in the patient's serum. After the diagnosis of systemic autoimmune disease was established, intravenous immunoglobulin therapy was administered. RESULTS: Direct immunofluorescence of the conjunctiva revealed linear deposition of IgA and IgG, and C3 at the epithelial basement membrane zone. Immunoblot analysis demonstrated the presence of IgG antibodies in patient serum directed against a 290-kDa protein in human skin. A diagnosis of epidermolysis bullosa acquisita was established. All signs and symptoms improved dramatically 4 months after initiation of intravenous immunoglobulin therapy and remained stable during follow-up. CONCLUSIONS: Epidermolysis bullosa acquisita can manifest in the eye as chronic cicatrizing conjunctivitis indistinguishable from ocular cicatricial pemphigoid. A nonconventional diagnostic tool (immunoblot assay) might be helpful in establishing the diagnosis of an underlying systemic autoimmune disease in patients with chronic cicatrizing conjunctivitis. Intravenous immunoglobulin therapy was effective against chronic cicatrizing conjunctivitis associated with epidermolysis bullosa acquisita.

Adult↗

PubMed1988

Local antibody production and immune complex formation in rats experimentally infected with Angiostrongylus cantonensis.

The systemic humoral immune responses and tissue localization of worm-antigen, antibodies (IgG), and complement (C3) were examined in rats experimentally infected with Angiostrongylus cantonensis. While the worms remained in the subarachnoid space, it was infiltrated with plasma cells and lymphoid cells containing IgM and IgG. When the infiltration of these cells became more pronounced, the serum antibody titer began to increase. At the same time, deposits of IgM, IgG, and C3 were found in the glomeruli of the kidney. A number of eggs were observed in the lungs, enclosed in granulomatous tissues. Infiltrates of plasma cells including IgM and IgG, and deposits of IgM, IgG, and C3 were detected around the eggs and in the granulomatous tissues. A marked increase in serum antibody was observed. A. cantonensis larvae induce local antibody (IgM and IgG) production in the central nervous system prior to an increase of serum antibody titer. Measurement of cerebrospinal fluid antibody titer at an early stage of infection may confirm infection. The larvae showed no evidence of damage in spite of marked local antibody production in the central nervous system. The eggs in the lungs stimulated both local and systemic antibody production, and immune complexes were formed in the lung and the circulatory system. Immune complexes may participate in the formation of granuloma.

Angiostrongylus↗

PubMed2000

Ability of xeno- and phytoestrogens to modulate expression of estrogen-sensitive genes in rat uterus: estrogenicity profiles and uterotropic activity.

The function of the uterus is regulated by female sex steroids and it is, therefore, used as the classical target organ to detect estrogenic action. Uterine response to estrogens involves the activation of a large pattern of estrogen-sensitive genes. This fact offers the opportunity to analyze the estrogenic activity of xeno- and phytoestrogens, and the mechanisms of their molecular action by a correlation of the uterotropic activity and their ability to modulate the expression of estrogen-sensitive genes. We have analyzed the expression of androgen receptor (AR), progesterone receptor (PR), estrogen receptor (ER), clusterin (CLU), complement C3 (C3), and GAPDH mRNA in the rat uterus following oral administration of ethinylestradiol (EE), bisphenol A (BPA), o,p'-DDT (DDT), p-tert-octylphenol (OCT) and daidzein (DAI). A significant stimulation of the uterine wet weight could be observed after administration of all the substances. The activity of all analyzed compounds to stimulate uterine weight was low in comparison to EE. DDT has the highest activity to stimulate uterine weight whereas BPA and DAI turned out to be less potent. The analysis of gene expression revealed a very specific profile of molecular action in response to the different compounds which cannot be detected by judging the uterotropic response alone. A dose dependent analysis revealed that C3 mRNA is already modulated at doses where no uterotropic response was detectable. Although DAI and BPA were very weak stimulators of uterine growth, these substances were able to alter the expression of AR, ER and C3 very strongly. Based on these investigations the analyzed compounds can be subdivided into distinct classes: First, compounds which exhibit a similar gene expression fingerprint as EE (e.g. OCT); second, compounds exhibiting a significant uterotropic activity, but inducing a pattern of gene expression different from EE (e.g. DDT); and third, compounds like BPA and especially DAI which exhibit a very low uterotropic activity, but nevertheless modulate the expression of estrogen-sensitive genes. These findings strongly suggest that the fingerprint of uterine gene expression is a very sensitive tool to investigate estrogenicity of natural and synthetic compounds and offers the possibility to get information in regard to the molecular mechanisms involved in the action of the respective compounds.

Animals↗

PubMed1998

Evaluative laboratory testing practices of United States rheumatologists.

OBJECTIVE: Several laboratory tests can be used to monitor disease activity in patients with rheumatic diseases. We sought to learn how rheumatologists use evaluative laboratory tests in the care of patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. METHODS: We surveyed United States rheumatologists by mailed questionnaire. Of the 976 rheumatologists who received the questionnaire, 575 responded, for a response rate of 59%. RESULTS: Eighty-six percent of the respondents reported using either the erythrocyte sedimentation rate (ESR) or C-reactive protein level to monitor patients with RA, 92% used either the anti-DNA antibody level or complement C3 level to monitor patients with SLE, and 95% used either the ESR or ANCA levels to monitor patients with ANCA-associated vasculitis. The frequency of testing was distributed over a broad range, but testing was common. Testing on 50% of the visits or more was reported by 52% of respondents for RA, 59% of respondents for SLE, and 64% of respondents for ANCA-associated vasculitis. Between 7% and 11% of respondents reported testing patients on every visit, regardless of clinical disease activity. The majority of respondents reported not altering the treatment of clinically stable patients based on these test results. CONCLUSION: Evaluative laboratory testing is common, and is rarely used as an independent guide for treatment.

Antibodies, Antineutrophil Cytoplasmic↗

PubMed1996

Antiplatelet antibody testing in thrombocytopenic pregnant women.

OBJECTIVE: The purpose of the study was to attempt to distinguish pregnant women with gestational thrombocytopenia from those with idiopathic immune thrombocytopenia by eight different platelet antibody assays. STUDY DESIGN: Sera from pregnant women with presumed gestational thrombocytopenia (n = 160) and idiopathic immune thrombocytopenia (n=90) were prospectively tested for indirect and platelet-associated immunoglobulins G and M and complement C3, as well as for serotonin release. After the results were analyzed, a subset of patients were subsequently analyzed for circulating antiplatelet antibody directed against platelet membrane glycoprotein GPIIb/IIIa. RESULTS: Indirect immunoglobulin G was significantly greater in the 85 women with idiopathic immune thrombocytopenia than in the 129 women with gestational thrombocytopenia (p<0.001). Platelet-associated immunoglobulin G was elevated in the majority of women, both those with gestational thrombocytopenia and those with idiopathic immune thrombocytopenia. There were also no statistically significant difference in the values for platelet-associated C3 or indirect immunoglobulin M and C3. Levels of platelet-associated immunoglobulin M showed a tendency to be higher in women with gestational thrombocytopenia (p=0.04), as did the values in the serotonin release assay (p=0.06). CONCLUSION: Our data demonstrate that patients with gestational thrombocytopenia had surprisingly high levels of platelet-associated immunoglobulin despite mild thrombocytopenia. Comparison of a relatively large number of patients with idiopathic immune thrombocytopenia and gestational thrombocytopenia indicates that women with idiopathic immune thrombocytopenia cannot be distinguished from those with gestational thrombocytopenia by means of one or more of the prototypic platelet antiglobulin tests currently in use. Our preliminary data with glycoprotein-specific assays indicate that they may be more useful.

Autoantibodies↗

PubMed1999

Uteroglobin is essential in preventing immunoglobulin A nephropathy in mice.

The molecular mechanism(s) of immunoglobulin A (IgA) nephropathy, the most common primary renal glomerular disease worldwide, is unknown. Its pathologic features include hematuria, high levels of circulating IgA-fibronectin (Fn) complexes, and glomerular deposition of IgA, complement C3, Fn and collagen. We report here that two independent mouse models (gene knockout and antisense transgenic), both manifesting deficiency of an anti-inflammatory protein, uteroglobin (UG), develop almost all of the pathologic features of human IgA nephropathy. We further demonstrate that Fn-UG heteromerization, reported to prevent abnormal glomerular deposition of Fn and collagen, also abrogates both the formation of IgA-Fn complexes and their binding to glomerular cells. Moreover, UG prevents glomerular accumulation of exogenous IgA in UG-null mice. These results define an essential role for UG in preventing mouse IgA nephropathy and warrant further studies to determine if a similar mechanism(s) underlies the human disease.

Animals↗

PubMed1980

Leukocyte migration enhancement as an indicator of immunologic enhancement. III. Common denominators of pregnancy and malignancy.

Leukocyte migration enhancement (LME), a common denominator of pregnancy and malignancy, was investigated in order to determine the immunologic factors and processes involved in this in vitro assay. Reproducibility of results was confirmed by parallel investigations of single patients in an independent laboratory. Preliminary evidence also suggests that the phenomenon of LME is observable not only with the leukocyte migration assay, as performed in the present study, but also with the "indirect" migration inhibitory factor (MIF) assay. Highly significant correlation between results obtained with plasma (PL) and amniotic fluid (AF) was observed (p less than 0.00089). No significant correlation between LME and IgG concentrations as well as complement (C3) concentrations in AF and PL could be detected. C3 concentrations correlated significantly to gravity (p less than 0.007) and parity (p less than 0.003). No immune complexes were detected in either AF or PL samples. An unspecific protein effect as the cause of LME was ruled out in showing no significant correlation between LME and protein concentrations of AF and PL. A highly significant correlation between antigen concentration in PL and migration area was demonstrated (p less than 0.00001). It is suggested that leukocyte migration inhibition (LMI) represents a state of antigen excess, while LME represents antibody excess. Through selective removal of the IgG immunoglobulins LME could be converted into LMI, indicating an IgG subfraction as the responsible immunoglobulin in the phenomenon of LME.

Amniotic Fluid↗