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PubMed1998

[Immunocytochemical analysis of the inflammatory infiltrate in inclusion body myositis and other neuromuscular disorders with rimmed vacuoles].

Among 1400 muscle biopsies, we found 16 cases with rimmed vacuoles whose diagnosis were sporadic inclusion body myositis (IBM) (4 cases), juvenile spinal muscular atrophy (6 cases), distal myopathies (3 cases), limb-girdle muscular dystrophy (2 cases), and peripheral neuropathy (1 case). Monoclonal antibodies reactive for T lymphocytes and subsets, B lymphocytes, macrophages, natural killer cells, immunoglobulins, and complement were used to analyze the inflammatory infiltrate. The analysis was quantitative and according to the site of accumulation (interstitial, endomysial, and perivascular). The immunocytochemical analysis showed CD8+ lymphocytes in the interstitial in most cases, occasionally inside of muscle fibers, and rarely in the perivascular region. The IBM cases had an increased number of CD8+ lymphocytes comparing with the other diseases. CD8+/CD4+ ratio was increased in IBM compared with the other diseases. Macrophages were frequent in IBM, distal myopathy, and one case of limb-girdle muscular dystrophy. Natural killer cells were frequent at interstitial.

Adolescent↗
PubMed2000

[Isotyping of human C4 complement using differences in the functional activity of C4A and C4B isotypes].

The difference in the functional activity of the isotypes A and B of component C4 of human complement was used to determine their ratio and to detect the inherited deficiency of the isotypes. ELISA methods were developed for the quantitative assay of component C4 (conventional sandwich method) and its functional activity. When determining the functional activity, the classic pathway of the complement and therefore of component C4 was activated by activators sorbed on ELISA microplates (immunoglobulin IgG3 or liposaccharide of the Shigella sonnei cell walls, which activates the complement by binding component C1). The nascent fragment C4b is covalently bound to the target activator; C4Ab binds better to the target protein (immunoglobulin), and C4Bb to the target carbohydrate (liposaccharide). Therefore, when immunoglobulin is a target activator, isotype C4A is bound and determined; and when the complement is activated by liposaccharide, isotype C4B is determined. The ratio of the activities determined by the two methods indicates a deficiency in the individual isotypes of component C4 or its absence. The rabbit polyclonal monospecific antibodies against the human component C4 and the conjugates of these antibodies with horseradish peroxidase were used in the methods described.

Animals↗
PubMed1992

Induction of arthritis with monoclonal antibodies to collagen.

mAb were developed from DBA/1 mice immunized with chick type II collagen. A total of 69 IgG antibodies was isolated and characterized. The majority (36%) reacted with a CNBr-derived peptide CB11 previously identified as containing a major immunogenic and arthritogenic epitope(s). Seven of the antibodies reactive with CB11 crossreacted strongly with mouse type II collagen. These were administered to DBA/1 mice in an attempt to induce arthritis. Individual antibodies were able to induce mild lesions consisting of minimal synovial proliferation but not overt arthritis. However, a combination of antibodies induced severe arthritis with marked destruction of articular cartilage. The minimal effective combination consisted of three antibodies. Arthritis developed within 48 to 72 h after injection of the antibodies and persisted for the duration of the observation period of 3 wk. Antibody levels were measured at intervals and persisted for the 3 wk observation period although at diminishing levels. Competitive binding assays demonstrated that each of the effective antibodies bound independently suggesting that some spatial or quantitative relationship was important possibly related to their ability to activate complement.

Animals↗
PubMed1992

The effects of cardiopulmonary bypass on thyroid function in infants weighing less than five kilograms.

Triiodothyronine is an important regulator of cellular metabolism and may have potential use as an inotropic agent. The aim of this study was to determine the effects of cardiopulmonary bypass on thyroid function in infants weighing less than 5 kg. Serial measurements of triiodothyronine, thyroxine, and thyroid-stimulating hormone were made in 10 infants and corrected for the effects of hemodilution. We demonstrated a fall in triiodothyronine and thyroxine levels, with some recovery after 3 to 6 hours. An additional decrease then occurred, reaching a trough at 48 hours (representing a fall of 78% for triiodothyronine and 57% for thyroxine) before hormone levels returned to normal at 5 to 7 days. Thyroid-stimulating hormone concentrations increased and decreased, predating and complementing exactly the changes in triiodothyronine and thyroxine. These results are quantitatively and, for thyroid-stimulating hormone, qualitatively different from those previously reported in adults. In two patients who died, however, and in one who had a particularly difficult postoperative course, no increase in triiodothyronine, thyroxine, or thyroid-stimulating hormone concentrations was found after a trough had been reached at 48 to 72 hours, which suggests abnormal function at the hypothalamopituitary level.

Body Weight↗
PubMedDate not supplied

Current problems and future requirements for 5-hydroxytryptamine receptor classification.

The present scheme for classifying and naming 5-hydroxytryptamine (5-HT) receptors is being challenged by a growing number of reports that describe receptor types that fail to meet the criteria for admission into the "5-HT1-like," 5-HT2 or, 5-HT3 classes. Consequently, there is an increasing tendency for authors to make unilateral designations for new receptor classes in the absence of any formal criteria for their classification. This hinders rather than helps in establishing the minimum safe criteria for receptor definition and emphasizes the need to update the current scheme. In this article a number of factors are considered that might contribute to instability in 5-HT receptor classification and attention is drawn in particular to the generally unreliable behavior of available chemically heterogeneous antagonists. Experiments with tryptamine agonists and antagonists, although limited in number, suggest that close chemical analogs of the natural receptor agonist 5-HT provide a quantitatively stable and therefore more secure basis for classification, which usefully complements and extends the currently accepted proposals. Furthermore, an approach based on hormone analogs focuses attention on the objectives of the classification process as well as a definition for the term receptor. These issues are germane to the development of a unifying scheme for receptor taxonomy and have been considered here in terms of the current problems and future requirements of 5-HT receptor classification.

Animals↗
PubMed1979

Forssman-like antibody levels in sera of patients with lung cancer.

Sera of normal individuals or patients with lung cancer were assayed for Forssman-like antibody by a quantitative and specific method using ethylenediaminetetraacetate-containing buffer to inactivate complement in the test serum. It was shown that although Forssman-like antibody levels were distributed widely, (a) the levels of young (20 to 45 years of age) normal subjects of Blood Groups A and AB were lower than those of Blood Groups O and B, (b) the levels of old (60 to 80 years of age) normal subjects were lower than those of young normal subjects of Blood Groups O and B, and (c) the levels of old lung cancer patients were lower when compared to age-matched normal individuals of their blood group.

ABO Blood-Group System↗
PubMed1982

Cross-reacting antigens on L5178Y cells which serve as targets for cytotoxic T-lymphocyte lysis during establishment of the tumor dormant state.

We have attempted to identify the antigen on L5178Y cells that is the target for peritoneal cytotoxic T-lymphocytes (CTL) generated in L5178Y-O (original) immunized and challenged DBA/2 mice during establishment of the L5178Y cell tumor dormant state. These CTL exhibited in vitro lytic activity against methylcholanthrene-induced L5178Y and P815Y cells as well as Gross virus-induced BALB/c cells but not against a variety of other H-2d-tumor cell lines. The pattern of susceptibility to cell-mediated immune cytolysis was identical to the pattern of AB-dependent complement-mediated cytolysis produced by a rabbit anti-L5178Y antiserum. Quantitative expression of surface H-2d determinants was not a limiting factor in tumor cell lysis by CTL. The degree of CTL lysis of the susceptible cell lines was directly related to the amount of tumor-associated antigen expressed on the cell surface. The pattern of in vitro susceptibility to CTL lysis correlated well with in vivo transplantation resistance. The L5178Y cell antigen target for both CTL and Ra-anti-L5178Y serum lysis is likely to be either an endogenous AKR ecotropic viral glycoprotein with a molecular weight of 71,000 or one of two cell surface determinants, at Mr 85,000 and 135,000. These higher-molecular-weight antigens are neither endogenous AKR ecotropic viral-induced nor murine leukemia virus group-specific precursor structural proteins but may be transformation antigens shared by the susceptible tumor cell lines.

Animals↗
PubMed1995

[Techniques for the diagnosis of kidney diseases. Is there a role for the immunoperoxidase method in the evaluation of immunologic glomerulopathy on biopsy specimens, including those in paraffin? Our experience: preliminary results].

Firstly an extensive summary of the diagnostic power and limits in renal glomerular pathology of light microscopy even corroborated by all the special histochemical stains is made. Secondly a complete list of all those renal glomerular diseases in which electron microscopy is unanimously considered necessary for the diagnosis is given as well as the main and most updated references pertinent to those rare and recently recognized pathological entities in which EM proved as a fundamental diagnostic tool are provided. Thirdly the authors focus on the importance of immunohistochemistry (IIC) in the diagnosis of immune-mediated renal glomerular diseases. The advantages and disadvantages of immunofluorescence microscopy (IF) and immunoperoxidase method (I-perox) are respectively discussed. The value of I-perox staining method applied to sections from paraffin blocks is emphasized and some technical suggestions in order to optimize results are given. Among the latter the choice of the used fixative for the purpose of preserving antigenicity of immunoglobulins and complement fractions, the timing of tissue fixation as well as the quantitation of enzymatic pretreatment relative to the duration of fixation, and the repeated washings with phosphate-buffer saline to minimize background staining. Ultimately the authors report on their preliminary personal results with the use of I-perox staining on sections from paraffin embedded renal core biopsies. Although if is their favourite diagnostic microscopy for evaluating renal immunopathology the authors underline I-perox method as a helpful tool to rely on at least in those circumstances when frozen material for IF is not available due to the scarcity of core biopsy, when glomeruli are absent in frozen sections, or when due to a technical lab accident the frozen tissue devoted to IF has been ruined or lost, and the only available material is the one which lies embedded in paraffin. The LSAB ("labelled streptavidin biotin") complex and PAP ("peroxidase-antiperoxidase") working procedures are provided in detail.

Biomarkers↗
PubMed2006

Quantitative analysis of La Crosse virus transcription and replication in cell cultures and mosquitoes.

La Crosse (LAC) virus (family Bunyaviridae, genus Orthobunyavirus) small (S) segment negative-sense RNA genome (vRNA), positive-sense full-length RNA complement (vcRNA), and subgenomic mRNA were assayed in infected cell cultures and female Aedes (Ochlerotatus) triseriatus mosquito tissues using quantitative PCR (Q-PCR). During persistent infection of C6/36 (Aedes albopictus) and MAT (Aedes triseriatus) cultured cells and cytolytic infection of BHK-21 cultured cells, LAC vRNA was the most abundant RNA species, followed by mRNA and vcRNA. RNA copy numbers per cell were quantified and vRNA correlated to virus titer in cell culture medium. The Q-PCR assay proved more sensitive than reverse transcription (RT)-PCR and immunofluorescence assays (IFA) for detecting LAC virus infection of mosquitoes. After infection of female mosquitoes orally, quantities of LAC RNA increased in ovaries for 6 days, and as ovarian biosynthetic activity quiesced, LAC RNA quantities decreased then remained detectable at a low level. After a second, noninfectious blood meal, quantities of LAC RNA in ovaries increased significantly, quantitatively confirming correlation of LAC virus RNA synthesis with vector metabolic activity. Coregulation of viral replication and mosquito ovary metabolic activity may condition efficient transovarial transmission.

Aedes↗
PubMed1978

Evidence for quantitative variability of bacterial opsonic requirements.

We studied human serum opsonins by using combinations of heat inactivation and chelation to inhibit complement, adsorption to remove antibody, and trypan blue to inactivate the C3 receptor of human polymorphonuclear leukocytes. Streptococcus pneumoniae, serotype 25, required both complement and immunoglobulin for opsonization, even though that strain activated the alternative complement pathway. Both strains of Escherichia coli required antibody and complement, but varied in the degree of dependence on the C3 opsonin, since trypan blue moderately inhibited the killing of E. coli-1 and markedly inhibited the killing of E. coli-2. Serratia marcescens was opsonized in heat-inactivated serum (limited complement) or serum absorbed at 0 degrees C with S. marcescens (limited antibody), but depended on the C3 receptor in absorbed serum. S. marcescens activated the alternative pathway. Thus, opsonic requirements varied with the availability of opsonins. Requirements for bacterial opsonization vary with species and strains within species, perhaps reflecting quantitative relationships among alternative and classical pathway activation of C3, efficiency of adsorption of C3 or immunoglobulin G to bacterial surfaces, and efficiency of attachment of these ligands to polymorphonuclear leukocyte receptors. Furthermore, although not always sufficient for opsonization, the C3 opsonin (activated through either the classical or alternative pathway) appears necessary for effective phagocytosis and killing of all strains studied.

Antibodies, Bacterial↗
PubMed1992

Rapid complementation assay for anti-HIV-1 drug screening and analysis of envelope protein function.

A complementation assay is described that can be used with relative safety to quantitate rapidly inhibitory effects of potential anti-HIV-1 drugs on virtually any stage of the HIV-1 life cycle by measurements of chloramphenicol acetyltransferase (CAT) activity. Of particular interest is that this system is also capable of detecting inhibition of the viral trans-activator Rev, an important potential target for drug intervention. Other applications of the system may include studies to identify domains of the envelope glycoprotein that determine infectivity and tropism or that define epitopes recognized by neutralization antibodies.

Antiviral Agents↗
PubMed1993

Complement activation by gp160 glycoprotein of HIV-1.

The ability of the gp160 envelope glycoprotein of HIV-1 to activate human complement and to bind C3 fragments was investigated by incubating mammalian-derived recombinant gp160 with seronegative serum and by quantitating the binding of C3b/iC3b to the protein using a biotinylated monoclonal antibody directed against a neoepitope expressed by cleaved human C3. Recombinant gp160 activated complement in a dose- and time-dependent fashion. Complement activation occurred through the classical pathway, independently of antibodies, and required C1q. Binding of anti-HIV IgG to rgp160 prior to exposure of the envelope glycoprotein to serum resulted in enhanced complement activation. Complexes of rgp120 with anti-HIV IgG also cleaved C3 in serum, resulting in deposition of C3b on gp120. These results provide a basis for C3-mediated facilitation of viral entry into target cells expressing receptors for fragments of human C3.

Antibody Specificity↗
PubMed1975

Immunochemical characterization of murine H-2 controlled Ss (serum substance) protein through identification of its human homologue as the fourth component of complement.

The S region of the mouse H-2 complex is genetically defined by a series of alleles, or pseudoalleles, which control the level of a serum globulin, Ss, and of its allotypic vairatn, Slp. In contrast with the products of other genes in the complex, no homologue of the Ss protein has been found in other species, except the rat. In the present study, a component in human plasma was identified which cross-reacts with anti-mouse Ss, and which also displays electrophoretic and size similarities to the mouse Ss protein. This component was isolated and characterized immunochemically as the fourth component of human complement (C'4 or beta1E globulin). Several antisera monospecific for human C'4 cross-react with the mouse Ss protein and detect its genetically determined quantitative variations.

Animals↗
PubMed2005

A wide range of protein isoforms in serum and plasma uncovered by a quantitative intact protein analysis system.

We have implemented an orthogonal 3-D intact protein analysis system (IPAS) to quantitatively profile protein differences between human serum and plasma. Reference specimens consisting of pooled Caucasian-American serum, citrate-anticoagulated plasma, and EDTA-anticoagulated plasma were each depleted of six highly abundant proteins, concentrated, and labeled with a different Cy dye (Cy5, Cy3, or Cy2). A mixture consisting of each of the labeled samples was subjected to three dimensions of separation based on charge, hydrophobicity, and molecular mass. Differences in the abundance of proteins between each of the three samples were determined. More than 5000 bands were found to have greater than two-fold difference in intensity between any pair of labeled specimens by quantitative imaging. As expected, some of the differences in band intensities between serum and plasma were attributable to proteins related to coagulation. Interestingly, many proteins were identified in multiple fractions, each exhibiting different pI, hydrophobicity, or molecular mass. This is likely reflective of the expression of different protein isoforms or specific protein cleavage products, as illustrated by complement component 3 precursor and clusterin. IPAS provides a high resolution, high sensitivity, and quantitative approach for the analysis of serum and plasma proteins, and allows assessment of PTMs as a potential source of biomarkers.

Anticoagulants↗
PubMed1976

Antinuclear factors in sera from healthy blood donors.

Sera obtained from 466 healthy blood donors were investigated for presence of granulocyte-specific and organ-nonspecific antinuclear factors of the IgM, IgA and IgG classes, 110 sera also for complement-fixing and IgD class antinuclear factors. When undiluted sera were studied, most sera were found to contain antinuclear factors of one or more immunoglobulin classes (77 per cent). IgM, IgA and IgG antinuclear factors were found in 53, 44 and 14 per cent, respectively. At dilution 1:16, antinuclear factors of the IgM class were still detected in 16 per cent of the sera, while IgA and IgC antinuclear factors wre demonstrated in 6 and 2 per cent, respectively. Organ-nonspecific antinuclear factors were clearly more common than granulocyte-specific antinuclear factors. No serum contained complement-fixing or IgD class antinuclear factors. This study indicates the importance of using qualitative as well as quantitative techniques to distinguish between antinuclear factors in health and disease.

Adult↗
PubMed1978

Complement-mediated immune mechanisms in renal infection.

The belief that the inactivation of complement by renal ammonia enhances the susceptibility of renal tissue to infection has been held for some years. This thesis has been investigated in the present experiments using cultures of renal tissue maintained in vitro under physiological conditions. The experiments have confirmed that exposure of normal serum to renal issue in culture does result in the rapid loss of complement activity, but that the inactivation was not due to renal ammonia. Furthermore, in quantitative experiments, the liver was found to have even greater anti-complementary activity than renal tissue. In experiments where the biological significance of this phenomenon was examined, it was shown that the bactericidal capacity of serum was maintained even after exposure to renal tissue. The results of these investigations suggest that the biological significance of the inactivation of complement by renal tissue in vitro has been over-emphasized and requires further studies in vivo.

Ammonia↗
PubMed1990

Demyelination induced in aggregating brain cell cultures by a monoclonal antibody against myelin/oligodendrocyte glycoprotein.

A monoclonal antibody (8-18C5) directed against myelin/oligodendrocyte glycoprotein (MOG) induced demyelination in aggregating brain cell cultures. With increasing doses of anti-MOG antibody in the presence of complement, myelin basic protein (MBP) concentration decreased in a dose-related manner. A similar, albeit less pronounced, effect was observed on specific activity of 2',3'-cyclic nucleotide 3'-phosphohydrolase. In the absence of complement, anti-MOG antibody did not induce detectable demyelination. In contrast to the effect of anti-MOG antibody and as expected, anti-MBP antibody did not demyelinate aggregating brain cell cultures in the presence of complement. These results provide additional support to the suggestion that MOG, a quantitatively minor myelin component located on the external side of the myelin membrane, is a good target antigen for antibody-induced demyelination. Indeed, they show that a purified anti-MOG antibody directed against a single epitope on the glycoprotein can produce demyelination, not only in vivo as previously shown, but also in cultures. Such an observation has not been made with polyclonal antisera raised against purified myelin proteins like MBP and proteolipid protein, the major protein components of the myelin membrane, or myelin-associated glycoprotein. These observations may have important implications regarding the possible role of anti-MOG antibodies in demyelinating diseases.

2',3'-Cyclic Nucleotide 3'-Phosphodiesterase↗
PubMed1978

Assembly of the cytolytic alternative pathway of complement from 11 isolated plasma proteins.

The known cytolytic function of the alternative pathway in serum was quantitatively reproduced by combining 11 isolated plasma proteins at their respective serum concentrations. These proteins are: C3, Factor B, Factor D, C3b inactivator, beta1H, native properdin, C5, C6, C7, C8, and C9. In absence of activators of the alternative pathway, this mixture was stable at 37 degrees C as evidenced by lack of consumption of Factor B, C3, and C5. Upon addition of either rabbit erythrocytes or neuraminidase-treated sheep erythrocytes, cell lysis ensued and the extent of lysis was dependent on dose of the component mixture. The dose-response curves obtained with the isolated component mixture and with C4-depleted serum were virtually indistinguishable. Nonactivator erythrocytes (untreated sheep erythrocytes) were not lysed by the component mixture. Deletion of properdin resulted only in a twofold diminution of the hemolytic activity of the component mixture. No immunoglobulin requirement was apparent. These results indicate that the cytolytic systems studied are internally sufficient and capable of coupling the initiation and amplification sequence with the cytolytic membrane attack sequence.

Cell-Free System↗