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N J Calvanico

Publications and source records attributed to N J Calvanico.

At least 19 recordsLinked to original sources
PubMed1994

A non-desmoglein component of bovine epidermis reactive with pemphigus foliaceus sera.

A component from bovine epidermis has been purified and found to react with sera from patients with pemphigus foliaceus (PF). This component appears to have molecular weight characteristics similar to those of a previously reported component of human and bovine epidermis which was reactive with PF sera, but only detectable by radiolabeling. It is composed of an 80 kD and a 45 kD polypeptide which are thought to be covalently linked. By chromatographic data, the native form appears to be a noncovalently joined dimer of the 80 and 45 kD polypeptides. Amino acid analysis and sequence data indicate that the 80 kD component is not desmoglein (DG) nor any other known protein whose sequence is entered in data banks. Previous studies by Stanley indicate that DG is the major target of autoantibodies in PF sera. Our finding of another epidermal component reactive with PF antibodies raises some questions. It is not yet known if PF anti-DG antibodies cross-react with this new epidermal antigen or if these antibodies constitute separate and non-cross-reacting sets. Both possibilities and their ramifications are discussed.

Amino Acid Sequence↗
PubMed1993

Affinity immunoblotting studies on the restriction of autoantibodies from endemic pemphigus foliaceus patients.

Endemic pemphigus foliaceus or Fogo Selvagem (FS) is an autoimmune blistering skin disease mediated by autoantibodies directed against components on the surface of subcorneal keratinocytes. All patients have high titers of these autoantibodies in the IgG4 subclass as determined by indirect immunofluorescence on frozen skin sections. In addition, patients may also have autoantibodies in other IgG subclasses, particularly IgG1, but the titers in these subclasses are significantly lower than those found in the IgG4 subclass. We have now found that in addition to isotype preference, autoantibodies from FS patients show clonal restriction as evidenced by oligoclonal banding on isoelectric focusing after probing with extracts from both human and bovine epidermis. Both IgG1 and IgG4 exhibit oligoclonal banding, but the distribution of these bands in the pH gradient differs for these two subclasses. Whereas the IgG4 oligoclonal bands are distributed throughout the IgG4 pH range, IgG1 banding appears to be concentrated in the more basic region of the IgG1 pH range. This finding suggests that the IgG1 autoantibodies have undergone selective somatic mutation by a negatively charged autoantigen. Similar findings have been reported for pathogenic DNA autoantibodies associated with SLE. The wide distribution of IgG4 banding suggests that this response may have followed the IgG1 response and has not undergone selective mutation. Both IgG1 and IgG4 appear to be Ca++ dependent autoantibodies.

Adult↗
PubMed1993

The humoral immune response in autoimmunity.

Only within the last 5 years have data on variable region sequences of autoantibodies begun to accumulate. Although it is too early to draw final conclusions, certain principles are beginning to emerge. It is clear that self-recognition by the immune system is normal. This fact is supported by the anti-idiotype network and the presence of natural autoantibody in normal sera. Furthermore, there appears to be a connection between these phenomena because the former may serve to keep the latter in check. Natural autoantibody appears to be primarily IgM polyreactive antibody of low affinity, quite different from the monospecific high-affinity IgG antibody usually associated with autoimmune disease. Natural autoantibodies also exhibit a high degree of cross-reactive idiotypes and are the products of CD5+ B cells, whereas IgG autoantibody is not. This is only a generalization, however, and it must be kept in mind that IgG autoantibody polyreactive with several autoantigens has been reported for normal sera of mice and humans. In Balb/c sera, a significant proportion of natural autoantibody is IgG, but it is apparently masked by inhibitory polyreactive IgM antibody that has affinity for IgG autoantibody, thereby exhibiting a regulatory role. A human CD5+ B-cell clone that secretes a high-affinity IgM anti-idiotype-specific antibody has been reported. Another generalization that is beginning to emerge is that natural autoantibodies are the products of unmutated germline genes, whereas autoantibody associated with autoimmune disease has highly mutated VH and VL segments. Mutations exhibited by pathogenic autoantibody increase the antibody's affinity for autoantigen and therefore represent an antigen-selected or affinity maturation, resulting in more restricted heterogeneity. In contrast to this, polyreactive natural antibodies have variable regions that are essentially identical to germline gene V segments with few amino acid changes. However, it is important to note that pathologic autoantibodies arise from the same fetal genes that give rise to natural autoantibodies and antibodies against foreign antigens. There does not appear to be a set of genes specific for autoantibodies. The key question then becomes whether or not natural autoantibodies are precursors of pathogenic autoantibodies. If not, what is the function of natural autoantibodies and how do pathogenic autoantibodies arise? The answers to these questions are not yet clear and many theories have been offered, but sufficient data are not yet available to reach conclusions. One of the problems in reaching a definitive conclusion is the ability to identify pathogenic antibody.(ABSTRACT TRUNCATED AT 400 WORDS)

Agglutinins↗
PubMed1991

Characterization of pemphigus foliaceus antigen from human epidermis.

Pemphigus foliaceus (PF) and its endemic form, Fogo Selvagem (FS), are characterized by subcorneal vesicles and pathogenic IgG autoantibodies directed against keratinocyte surface antigens. A major pool of FS antigen(s) remains bound to the insoluble epidermal envelope fraction. In this paper we demonstrate that this antigen(s) can be released from the envelope fraction by sonication. By immune precipitation four components can be detected, having molecular weights (MW) of 260, 80, 62, and 45 kD. The 260-kD component is lost by boiling or extraction with glycine HCl at pH 2.8. The major components appear to be the 80- and 62-kD poly-peptides. They chromatograph as a unit by gel filtration in 0.1% SDS, in the MW range of 115-120 kD. The FS antigen(s) appears to be cationic, forming insoluble complexes at low pH with SDS, and is labile to ammonium sulfate and freezing and thawing. It is unaffected by positive pressure concentration, 50% acetone precipitation, and reduction/alkylation. The FS antigen(s) is precipitated by all FS and nonendemic PF sera except those in complete clinical and serologic remission. The FS antigen(s) is also precipitated by 50% of pemphigus vulgaris but none of the bullous pemphigoid sera tested. All FS antigenic components are immunoprecipitated by IgG4 autoantibodies, but the IgG1 subclass from the same patients appear to immunoprecipitate only the 62-kD polypeptide. The FS antigen(s) is able to adsorb human autoantibodies against human desmoglein 1 (DG1), but not rabbit antisera against bovine DG1 or 2. This paper shows that physical stress, i.e., sonication, may be able to solubilize sufficient FS antigen(s) from the epidermal envelope fractions for further chemical characterization. The relationship of these FS antigen(s) to other reported FS antigens is presently unknown.

Autoantigens↗
PubMed1987

Splenic regulation of the murine pulmonary lymph node response.

Exposure to intratracheal immunization and aerosolization with soluble antigen plus murmayl-dipeptide (MDP) induces the development of plaque-forming cells in the pulmonary draining lymph nodes of two of three inbred mouse strains. Splenectomy before immunization led to a heightened plaque-forming cell response in the two responder mouse strains. Adoptive transfer of spleen cells from one strain exposed to sperm whale myoglobin via the respiratory tract revealed the presence of antigen-specific suppressor cells. These observations suggest that the spleen may play a role in the down-regulation of an immune response elicited in the pulmonary draining lymph nodes by exposure of the respiratory tract to soluble antigens plus MDP.

Animals↗
PubMed1986

A component of pigeon dropping extract that reacts specifically with sera of individuals with pigeon breeder's disease.

A component of pigeon droppings has been demonstrated to react with sera of individuals with pigeon breeder's disease, a form of hypersensitivity pneumonitis, by crossed isoelectric focusing. Similarly, exposed but asymptomatic pigeon breeders do not exhibit antibody to this component, even though they possess significant levels of antibody to other components of pigeon droppings. Purification of this disease-specific component of pigeon dropping was attempted by preparative isoelectric focusing, gel filtration, and affinity chromatography on an immunoadsorbent prepared with asymptomatic antibody. After repeated passage over the affinity column, complete purification could not be achieved. A rabbit antiserum made against the partially purified component revealed the presence of at least one other component that did not react with either symptomatic or asymptomatic sera. Despite these contaminants, the disease-specific component was characterized as a single polypeptide having a molecular weight of approximately 50,000 daltons and having an isoelectric point between 3.5 and 5.1.

Alveolitis, Extrinsic Allergic↗
PubMed1986

Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on IgA serum and bile levels in rats.

Serum IgA is actively transported from blood to bile against a concentration gradient in the liver by the binding of dimeric IgA to secretory component, endocytosis and transport to the bile canaliculus by vesicles. As 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been shown to elicit hepatotoxicity, the effects of TCDD on rat serum and bile IgA levels were investigated. Rats were orally administered 50 micrograms TCDD/kg body weight in 95% corn oil: 5% acetone. At days 5, 10, 15, 20 and 30 after treatment, rats were anesthetized and a cannula inserted into the bile duct for collection of bile. In addition, blood was drawn, and, after euthanasia, the liver and thymus weights were recorded. Enzyme-linked immunosorbent assay (ELISA) techniques were employed to determine IgA in serum and bile and IgG levels in serum. Rocket immunoelectrophoresis was carried out to support ELISA results. It was found that serum IgA increased with time while serum IgG remained unchanged. In addition, while serum IgA levels were increasing, there was a concomitant decrease in biliary IgA. Thymus and liver weight changes were also observed. The data indicate that TCDD affects hepatic clearance of serum dimeric IgA and suggests that liver damage may be reflected by increased serum levels of IgA.

Animals↗
PubMed1986

Immunoglobulin G4 in pigeon breeder's disease.

Immunoglobulin G4 has previously been implicated in the pathogenesis of pigeon breeder's disease (PBD), a form of hypersensitivity pneumonitis associated with inhalation of pigeon antigens. We investigated the presence of IgG4 antibody to antigens in pigeon dropping extracts (PDE) in the lungs of pigeon breeders. Seven of these subjects had symptoms of PBD and eight others had no symptoms. IgG4 antibody to PDE was compared with IgG3 levels because both were relatively minor subclasses, but IgG3 is not considered reaginic whereas IgG4 is. An increase in IgG4 antibody relative to IgG3 would therefore be considered a selective increase and suggest a role for this subclass in the development of PBD. Our results, however, indicated that pigeon breeders without symptoms had significantly higher levels of serum IgG4 and that there were no significant differences with regard to the lavage fluid levels of IgG4, IgG3, or total IgG antibody in the two groups of subjects. A tendency of higher IgG4 antibody levels was found in lavage fluid from subjects without symptoms. These results do not support the hypothesis that IgG4 may act as a reaginic trigger in the development of PBD symptoms.

Adult↗
PubMed1985

Hemolytic plaque inhibition by synthetic antigenic peptides of sperm whale myoglobin.

We have investigated the systemic antibody response to sperm whale myoglobin (SWMb) antigenic sites in three strains of inbred mice using an inhibition of plaque assay. Sperm whale myoglobin was attached to sheep red blood cells (SRBC) via rabbit anti-SRBC Fab' fragments. Inhibition of lysis was obtained with synthetic peptides representing the purported five antigenic sites but not with a peptide whose sequence was unrelated to SWMb and synthetic peptides of SWMb from outside the antigenic sites gave minimal or no inhibition. The results of our studies show that the pattern of response to the five antigenic sites differs in each strain, but that almost total inhibition is obtained in all strains with these five sites. The antigenic dominance of these sites supports the concept of discrete antigenic sites on soluble proteins. They also suggest a reason for contrary reports in the literature based on hybridoma technology.

Animals↗
PubMed1985

Specificity and duration of post-inflammatory suppression in rabbit lungs challenged with aerosolized antigen.

Rabbits immunized and aerosolized with soluble protein antigens develop a short lived pulmonary inflammation. This is followed by a period of non-specific unresponsiveness which lasts approximately 30 weeks after the first exposure to aerosol treatment. This period is characterized by the inability of the rabbit to exhibit another inflammatory reaction either to the same antigen used to induce the first inflammation, or to a new antigenically unrelated antigen. After 30 weeks however, the animals become responsive (develop another pulmonary inflammation) to a second unrelated antigen, but remain unresponsive to the antigen used to elicit the initial inflammatory response. These studies indicate that following challenge with inhaled antigen, rabbits develop a non-specific suppression of pulmonary inflammation which lasts a finite period of time. When this disappears, the animal is left with an antigen specific suppression of pulmonary inflammation. These studies suggest a model for normal individuals who may respond similarly to potentially harmful inhaled allergens. Individuals with hypersensitivity pneumonitis, however, may not develop antigen specific unresponsiveness. The nature of this unresponsiveness is unknown at present, nor is it known when it begins to develop.

Aerosols↗
PubMed1985

Antigens of Aspergillus fumigatus. III. Comparative immunochemical analyses of clinically relevant aspergilli and related fungal taxa.

Cell sap (CS) of the pathogenic fungus Aspergillus fumigatus strain Ag-507 was fractionated by Sephadex G-200 column chromatography. A protein fraction designated CS3 was partially characterized by two dimensional electrophoresis (2-DE) and analytical ultracentrifugation. CS3 consisted mainly of low molecular weight components (14 K-43 K) of the whole CS, and produced one peak in analytical ultracentrifugation with an Sapp of 4.25. CS3 was demonstrated to be different from a previously characterized CS fraction designated as CS2, by 2-DE, and by CS2 and CS3 specific antisera. CS3 gave precipitin reactions with three aspergilloma patient sera and 100% of sera from allergic bronchopulmonary aspergillosis (ABPA) patients. Significantly, three ABPA patient sera reacted with CS3 and not CS2. The CS of A. fumigatus strains Ag-515 and Ag-534, were also examined for the presence of CS3 components as were CS preparations of five additional Aspergillus species; A. flavus, A. fischeri, A. terreus, Neosartorya (Aspergillus) fennelliae, and A. niger, and three fungal taxa; Penicillium notatum, Candida albicans, and Saccharomyces cerevisiae. 2-DE, immunoelectrophoresis and double diffusion (DD) analyses of the CS preparations provided complementary information. The immunochemical similarity of CS2 and CS3 components of different aspergilli appears to reflect the taxonomic relatedness of the aspergilli. Additionally, aspergilli exhibiting CS2 and CS3 components most similar to A. fumigatus strain Ag-507 are more frequently isolated from aspergillosis patients. There may be an association of these components with incidence of involvement of the organisms in aspergillosis. DD analysis of the cross-reactivity of CS of all taxa with ABPA and aspergilloma patient sera supported the 2-DE and absorption data.

Antigens, Fungal↗
PubMed1984

Suppressor macromolecules.

An amazing number of nonspecific and specific suppressor molecules that dampen immune reactivity have been described in the past two decades. This review, however, focuses on both nonspecific and specific endogenous suppressor macromolecules and attempts to group them into biochemically and functionally similar compartments. For the nonspecific inhibitors these groupings include normal serum protein suppressors; suppressor macromolecules found in altered states such as infectious disease, cancer, pregnancy, and malnutrition; and immunosuppressants derived from various tissues including both nonlymphoid and lymphoid tissue. In addition, suppressor macromolecules that display some degree of specificity are also included. The groupings for these proteins include those that are restricted in their response to a certain class of immunoglobulin antibody response, those that are restricted with respect to their actions by the major histocompatibility complex and those that are restricted with respect to antigen. Finally, this review attempts to rationalize the potential advantages and raison d'etre for conserving the plethora of both nonspecific and specific factors and speculates on their potential value in immune responses.

Animals↗
PubMed1984

Analysis of rabbit lung lavage immunoglobulins during the course of pulmonary inflammation induced with aerosolized antigen.

Lung lavage fluids (LLF) from rabbits with pigeon dropping extract (PDE)-induced granulomatous pulmonary inflammation were studied for protein and immunoglobulin (Ig) G and A levels. It was found that the protein levels of the lung fluids of rabbits increased to a maximum after 2-3 weeks of aerosol treatment with PDE during which time inflammation of the lung increases. This is followed by a gradual decrease in protein content as the inflammation wanes and the lung returns to normal. These variations primarily reflect changes in IgG and IgA levels. IgG and IgA levels follow different courses. IgA reaches a maximum in the first week of inflammation and then gradually decreases. In contrast, IgG reaches a maximum level (2-3 weeks) and stays at an elevated level throughout the 12 week period of aerosol treatment with PDE. Antibodies to PDE in these two classes of immunoglobulins do not entirely reflect the immunoglobulin class levels. IgA antibody levels reach a maximum after extended aerosol challenge while IgG antibody reaches a maximum early and then declines to background levels. The specificity of the non-PDE antibody IgG is unknown at present. The distribution of IgA subclass producing cells in the lung is different than in the gut. In the lung the major subclass is g while in the gut it is f. The distribution of subclasses of IgA in the LLF, however, does not appear to reflect the cellular distribution. The reason for this is not clear.

Aerosols↗
PubMed1983

Antigens of Aspergillus fumigatus. II. Electrophoretic and clinical studies.

Cell sap (CS) and culture filtrate (CF) preparations of Aspergillus fumigatus strains Ag-507, Ag-515, and Ag-534 were analysed by two dimensional electrophoresis (2-DE; i.e., first dimension isoelectric focusing, second dimension sodium dodecyl sulphate gradient pore gel), which enabled detection of strain- and species-specific components. In CS preparations it was shown that CS2, a fraction isolated from strain Ag-507 by gel filtration, consists of the major protein components in the CS of the three A. fumigatus strains tested. Culture filtrate preparations of the three A. fumigatus strains analysed by 2-DE exhibited patterns dissimilar to the CS patterns, as well as to each other, presumably due to proteolysis. Culture filtrate preparations are therefore a less reliable source of standardized antigens than CS preparations. CS2 has a major component with a mol. wt. of approximately 150,000 and an sapp of 6.3 S. CS2 reacts on immunoelectrophoresis, producing one major precipitin arc with aspergilloma or allergic bronchopulmonary aspergillosis (ABPA) patient sera. Antibody titres of the IgG and IgA classes to CS2, as measured by enzyme-linked immunosorbent assay (ELISA), were demonstrated to be similar in aspergilloma and ABPA patients; IgG titres were higher than IgA. Similar titres were also obtained utilizing sera of patients that did or did not exhibit precipitating antibodies to CS2. In the diagnosis of ABPA, skin tests with CS2 were comparable in specificity to currently available commercial preparations. Importantly, CS2 is a standardized major antigenic preparation of the CS of three A. fumigatus strains which has been shown to be diagnostically useful.

Antigens, Fungal↗
PubMed1982

Hypersensitivity pneumonitis in nonhuman primates. I. Studies on the relationship of immunoregulation and disease activity.

We investigated the relationship of immunoregulation to disease activity in a nonhuman primate model of pigeon breeder's disease. Two Macaca arctoides monkeys developed classical symptoms of hypersensitivity pneumonitis after sensitization and prolonged bronchial challenge, whereas 2 other monkeys remained asymptomatic after in vivo challenge. There were no differences in the percentages of T cells, B cells, monocytes, or FC gamma-bearing T cells between symptomatic and asymptomatic animals. Nonetheless, we found a population of concanavalin A-induced, pigeon serum- (PS) induced, and spontaneous T cells that functioned as suppressor cells in autologous in vitro co-cultures in asymptomatic animals that were missing or nonfunctional in symptomatic animals. Monocyte suppressors functioned in both groups. We used low-dose total body irradiation (TBI) to inactivate T suppressor cells. Fifteen radiation units of TBI caused no change in the physical activity, routine chemistries, or blood counts of the 4 animals. After TBI, however, the previously asymptomatic animals developed fever, tachypnea, and signs of pulmonary congestion after in vivo challenge with PS. There was no change in the response to challenge in the symptomatic group. This altered response to in vivo challenge in the previously asymptomatic group persisted for 2 wk after TBI. During this period the difference in vitro immunoregulatory activity between Con A-induced, PS-induced, and spontaneous T cells in symptomatic and asymptomatic animals disappeared. Monocyte suppressors, however, continued to function in both groups after TBI. These data suggest that the monkey is an appropriate model for studies of human HP and that T cell immunoregulation may be an important element in the pathogenesis and disease activity of HP.

Alveolitis, Extrinsic Allergic↗
PubMed1982

The antigens of pigeon breeder's disease. VII. Isoelectric focusing studies on unfractionated pigeon dropping extract.

Isoelectric focusing (IEF) studies on pigeon dropping extracts (PDE) revealed that it is a complex mixture of components that are acidic in nature. Chromatographically purified antigens PDEB, PDE1, and PDE3 showed multiple bands in IEF, indicating a microheterogeneity of these components, with peak concentrations focusing at pH 6.1, 4.6, and 3.8, respectively. The isoelectric points are compatible with the chromatographic behavior of these antigens on DEAE-cellulose. Crossed immunoelectrofocusing (CRIF) resolved PDE into seven precipitin lines with rabbit antiserum in a pH gradient from 3.5 to 9.5, and into nine precipitable components in a pH gradient from 2.5 to 7.0. The complexity of this antigen source appears to reside in the heterogeneity of immunologically related antigens. A comparison of pigeon breeder's sera by CRIF of PDE revealed a qualitative difference in precipitation patterns obtained with symptomatic and asymptomatic individuals. Sera from all (eight out of eight) of the symptomatic breeders tested precipitated an unidentified component of PDE, whereas none (zero out of four) of the sera from asymptomatic breeders detected this antigen. These results suggest that CRIF of PDE is useful as a diagnostic tool and that some specific component of PDE may be involved in the pathogenesis of the disease.

Alveolitis, Extrinsic Allergic↗