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R E Jordon

Publications and source records attributed to R E Jordon.

At least 37 records · Page 2Linked to original sources
PubMed1988

Expression of pemphigus vulgaris antigen in cultured human keratinocytes: effect of inhibitors, tunicamycin, and lectins.

We have investigated expression of pemphigus vulgaris antigen(s) in cultured human keratinocytes induced by the addition of extracellular calcium. Cycloheximide (10(-4) M) inhibited pemphigus antigen expression and stratification but actinomycin D (2 micrograms/ml) had no effect. Tunicamycin, which inhibits dolichol pyrophosphate-mediated glycosylation of asparaginyl residues specifically, was used to study the role of glycosylation. When calcium switching was carried out in the presence of tunicamycin, human keratinocytes did not stratify, and the expression of pemphigus antigen was partially inhibited and limited to cell-cell contact areas. Analysis of biosynthetically labeled proteins showed that the synthesis of high-molecular-weight proteins was markedly reduced in the tunicamycin-treated cells. A reciprocal blocking test demonstrated that concanavalin A and wheat germ agglutinin receptor share an epitope with pemphigus vulgaris antigen(s). These results suggest that Ca++, newly synthesized protein, and N-asparaginyl glycosylation are required for normal pemphigus antigen expression and epidermal stratification in vitro. Pemphigus vulgaris antigen may have a highly glycosylated, high-molecular-weight protein chain with carbohydrates playing an important role in epidermal cell morphology, adhesion, and stability of cell surface antigens.

Anti-Bacterial Agents↗
PubMed1988

Complement fixation by pemphigus antibody. V. Assembly of the membrane attack complex on cultured human keratinocytes.

Previous studies have shown that pemphigus vulgaris (PV) IgG will fix early complement components (C1q, C4, and C3) to cultured murine epidermal cell surfaces and that PV IgG and complement alter epidermal cell membrane integrity. The present study was undertaken to determine if assembly of terminal complement components (C5, C6, C7, C8, and C9) and expression of C5b-9 neoantigens occur when PV IgG interacts with human keratinocyte (HuK) cell surface antigens in the presence of a source of complement. Monoclonal antibodies specific for C5, C6, C7, C8, C9, and C5b-9 neoantigens were screened for reactivity to the individual complement components in an assembled complex of human C5b-9 on rabbit red blood cell ghosts. Monoclonal antibodies (tissue culture supernatants) that bound to antigenic determinants accessible in the C5b-9 complex were selected for this study using immunofluorescence methods. HuK treated with PV IgG fixed C5, C6, C7, C8, C9, and C5b-9 neoantigens in a characteristic speckled pattern, while normal IgG did not. Heat inactivation or EDTA treatment of the complement source, or substitution of C2-depleted serum abolished C5, C6, C7, C8, C9, and C5b-9 neoantigen staining. PV IgG and complement also resulted in significant cytotoxicity to cell membranes as assessed using an ethidium bromide-fluorescein diacetate assay. These results suggest that PV IgG will activate the membrane attack complex of the complement system on HuK cell surfaces, resulting in cytotoxicity to cell membranes, further implicating complement in the pathogenesis of pemphigus.

Autoantigens↗
PubMed1988

Complement fixation by Brazilian Pemphigus foliaceus autoantibodies.

This study was undertaken to determine if Brazilian Pemphigus foliaceus (BPF) autoantibodies will fix complement as do P. vulgaris (PV) autoantibodies. When sections of human skin were examined following indirect immunofluorescence (IF) staining, BPF autoantibodies reacted with the upper layers of epidermis, while PV autoantibodies were reactive with the lower layers. When tissue culture epidermal cells were used for indirect IF, BPF autoantibodies were not detected after plating until 24 h, while PV autoantibodies reacted within 18 h of plating. Using complement IF staining methods, BPF autoantibodies were found to fix C1q, C4 and C3 to whole skin sections in an intercellular pattern and to the surface of cultured keratinocytes. Although reactive with different epidermal cell surface antigens, autoantibodies in BPF will fix complement in a fashion similar to autoantibodies in PV.

Animals↗
PubMed1988

Complement fixation by pemphigus antibody. IV. Enhanced epidermal cell detachment in the absence of human plasminogen.

It has been reportedly previously that complement enhances pemphigus vulgaris antibody-induced epidermal cell detachment. The present studies were designed to eliminate the possibility of the human plasminogen-plasmin system contributing to the cell detachment observed in previous complement-mediated studies. To assay for the presence of protease contamination in the reagents, a simple, sensitive, caseinolytic-fluorometric assay was used. Confluent murine or human epidermal cell cultures were incubated with pemphigus IgG with and without complement and plasminogen. Detached epidermal cells, as determined by light microscopy and cell-counter analysis, were enumerated at 48 hours. Incubating pemphigus IgG with complement resulted in marked cell detachment, compared with minimal cell detachment when pemphigus IgG was incubated with plasminogen. Culture media were collected after 48 hours and assayed for activation of plasminogen. It was determined that the added plasminogen had not been activated, particularly in experiments where significant detachment was observed. The plasminogen could still be activated by streptokinase and urokinase. These studies suggest that epidermal cell detachment in pemphigus appears to be mediated at least in part by complement activation.

Acantholysis↗
PubMed1987

The particulate (speckled-like thread) nuclear staining pattern: species and cellular distribution of Ro/SSA antigen.

Anti-Ro/SSA antibodies are associated with a particulate (speckled-like thread) nuclear immunofluorescence (IF) staining pattern when human spleen imprints are employed as substrate. The present study was undertaken to determine if these antibodies would yield a similar IF pattern with splenic imprints from other species, and with other human cell lines. All splenic imprints (mammalian, avian, amphibian and fish origin) demonstrated a particulate nuclear pattern when treated with anti-Ro/SSA antibody positive serum samples. Cytospin preparations of a variety of peripheral blood cells also demonstrated this particulate pattern when treated with anti-Ro/SSA antibodies. Similar findings were noted when cytospin preparations of cultured keratinocyte cell lines were used as substrate. The antigen, associated with the particulate IF staining pattern when treated with anti-Ro/SSA antibody positive serum samples, is expressed in a variety of tissues and species.

Animals↗
PubMed1986

The application of glucose oxidase-labeled antibodies for the detection of proteins on nitrocellulose.

We have evaluated the sensitivity of immunostaining with glucose oxidase for the detection of monomeric human serum albumin (HSA) and monomeric human immunoglobulin G (IgG). A modification of a histochemical procedure was utilized by replacing phenazine methosulfate (PMS) with 1-methoxyphenazine methosulfate (mPMS) and by replacing Tris-HCl with Tris-citrate to improve the solubility of the tetrazolium compounds tested. mPMS is less sensitive to light, and may be stored for long periods in solution; it is now used routinely by histochemists in place of PMS in dehydrogenase cytochemistry. pH values of 6.3-8.3 were tested, with the reaction at pH 8.3 providing a slight increase in sensitivity. The reaction rate increased markedly as the pH became more alkaline. The minimum quantity of HSA detected was 3 ng applied directly to nitrocellulose and 10 ng when blotted. Human IgG was routinely detected at 250 pg and occasionally at 100 pg when dotted on the nitrocellulose.

Collodion↗
PubMed1986

Complement fixation by pemphigus antibody. III. Altered epidermal cell membrane integrity mediated by pemphigus antibody and complement.

The present study investigates the effects of pemphigus IgG and complement upon cell viability and/or membrane integrity using trypan blue exclusion, ethidium bromide (EB) staining, and fluorescein diacetate (FDA) conversion by living cells. Forty-eight-hour cultivated epidermal monolayers of neonatal BALB/c mice were incubated in media containing 1 mg/ml purified pemphigus IgG for 48 h in either the presence or absence of complement (absorbed AB sera). Adherent and detached cells were examined by both phase and fluorescence microscopy. Results from trypan blue exclusion showed that pemphigus IgG plus complement produced a modest decrease in exclusion of the dye compared to pemphigus IgG without complement. When FDA/EB comparisons were made, however, the differences were more substantial. When complement plus pemphigus IgG was added to cultures, the number of FDA-positive adherent cells decreased significantly and the number of EB-positive detached cells increased significantly. The effects of complement were inhibited by the use of heat-inactivated AB sera or by C1q depletion of AB sera. No significant effect on the cells was observed in the presence or absence of complement when pemphigus F(ab')2 fragments or when normal IgG was used. Plasminogen depletion of the complement source did not interfere with complement and pemphigus IgG effects as judged by the FDA/EB assay. These studies suggest that pemphigus antibody in the presence of complement alters cell membrane integrity and supports the contention that complement may play a significant role in the mechanism of acantholysis.

Animals↗
PubMed1986

Lupus erythematosus.

Lupus erythematosus represents a wide spectrum of diseases. Within this heterogeneity, however, several clinically relevant subsets have been found that may unite differing aspects of the disease and that may have pathogenic implications for the problem as a whole. Exciting links between genetic phenotypes, certain immune responses, and related cutaneous findings in neonatal, complement-deficient, subacute cutaneous, and ANA-negative lupus erythematosus and Sjögren's syndrome have been found. The increased frequency of the anti-Ro(SSA) antibody in these groups is notable. The ultraviolet light-altered immune system found in vivo and in vitro may also be relevant to disease pathogenesis. Even if the mechanisms elaborated are not the precise aberrations in lupus erythematosus, they may serve as an operational model for further research. Continued investigations into mechanisms of photoexacerbations in lupus erythematosus, as well as into genetically mediated immune response, may further our understanding of these disorders.

Adolescent↗
PubMed1985

Anti-Ro/SSA antibodies. Association with a particulate (large speckledlike thread) immunofluorescent nuclear staining pattern.

Twenty-one patients with clinical and histopathologic evidence of subacute cutaneous lupus erythematosus and one patient with Sjögren's syndrome and vasculitis had anti-Ro/SSA (Sjögren's syndrome A) antibodies as demonstrated by double immunodiffusion assay using a saline extract of human spleen as the source of antigen. These serum samples were negative when tested for other nuclear antigens, including native DNA, Sm, and RNP. When tested for antinuclear antibodies (ANAs) by immunofluorescence, only ten of 22 serum samples were ANA positive on mouse liver substrate, while 18 of 22 had a positive ANA when HEp-2 tumor cells were utilized. With imprints of human spleen as test substrate, all 22 serum samples yielded a positive ANA result and a particulate (large speckledlike thread) staining pattern. Absorption of two of these serum samples with human spleen extract containing Ro/SSA antigen inhibited both the particulate staining pattern using human spleen imprints and the anti-Ro/SSA precipitin line by double immunodiffusion. These studies suggest that anti-Ro/SSA antibodies and antibodies producing the particulate nuclear staining pattern on human spleen imprints are either one and the same or closely paralleling antibody systems.

Absorption↗
PubMed1985

Neonatal lupus erythematosus. A report of three cases associated with anti-Ro/SSA antibodies.

Three patients had neonatal lupus erythematosus syndrome. All three infants were girls who presented with characteristic skin lesions but without evidence of congenital heart block. All three mothers were asymptomatic at the time of delivery and have remained so until the present time. All mothers were positive for anti-Ro/SSA antibodies, as were the infants prior to 6 months of age. Anti-La/SSB antibodies were not present in either the mothers or the infants. HLA typing revealed that two of the mothers were positive for B8 and DR3, while the third mother was positive for B8 and DR2. Two of the infants were positive for B8 and DR3, while the third infant was positive for DR2 only.

Antibodies↗
PubMed1985

Immunopathologic mechanisms in pemphigus and bullous pemphigoid.

Pemphigus and bullous pemphigoid are autoimmune bullous diseases of the skin. Pemphigus, an intraepidermal blistering disease, is characterized by autoantibodies reactive with antigens located in the intercellular spaces or on the surfaces of epidermal cells. These antibodies, which have recently been shown to activate complement, appear to be the cause of the basic pathologic process of pemphigus, acantholysis. The complement system and the plasminogen-plasmin system may be important mediators in the detachment of epidermal cells. Bullous pemphigoid, a subepidermal blistering disease, is characterized by autoantibodies reactive with an antigen located in the lamina lucida region of the basement membrane zone. These autoantibodies, which will avidly fix complement, appear to mediate subepidermal separation by attraction of a variety of inflammatory cells. Anaphylatoxins, released by activation of C4 and C3, or specific IgE antibodies, may activate mast cells with release of ECF-A attracting eosinophils. With activation of C5, C5a is released which could attract polymorphonuclear leukocytes. Antigen-specific lymphocytes, which can also contribute histamine releasing substances, may also be involved. The exact mechanism by which the epidermis separates from the dermis in bullous pemphigoid, however, remains unresolved.

Adolescent↗
PubMed1985

Complement fixation by pemphigus antibody. II. Complement enhanced detachment of epidermal cells.

We have previously demonstrated that pemphigus antibodies will fix complement to organ and tissue cultured epidermal cells in vitro. In the present study, we sought to determine the role complement plays in the detachment of cultured murine epidermal cells by pemphigus antibody. Forty-eight hour cultivated epidermal monolayers from neonatal BALB/c mice were treated with purified IgG fractions of pemphigus sera in the presence or absence of complement. In the absence of complement, pemphigus IgG produced slight cell detachment when compared to an identical amount of normal IgG. When cells were maintained in media with pemphigus IgG plus complement for 48 h, the cell detachment was significantly higher than that obtained with pemphigus IgG alone, or with normal IgG plus complement. Heat inactivation or Clq depletion of the complement source resulted in complete inhibition of cell detachment. When pemphigus F(ab')2 plus complement was used instead of whole pemphigus IgG plus complement, the cell detachment rate was again lowered significantly. Both pemphigus IgG and the complement source were depleted of plasminogen by passage over a lysine-Sepharose 4B column, and tested for their effects on cell detachment depleted of plasminogen. Depletion of plasminogen failed to inhibit cell detachment induced by pemphigus IgG and complement. These results suggest that complement activated by pemphigus antibody binding to the epidermal cell surface induces epidermal cell detachment and would argue against the plasminogen-plasmin system as the sole cause of cell detachment in pemphigus.

Acantholysis↗
PubMed1984

Complement fixation by pemphigus antibody. I. In vitro fixation to organ and tissue culture skin.

Although complement is often detected in the intercellular substance of pemphigus skin lesions, the ability of pemphigus antibodies to fix complement in vitro is controversial. The purpose of this study was to test in vitro complement fixation abilities of pemphigus antibodies further using organ and tissue culture methods. Epidermal cell monolayers from mouse tail were incubated with the purified IgG fraction of pemphigus serum followed by purified Clq. Binding of Clq, as well as IgG was demonstrated by immunofluorescence methods. When purified Clq was replaced with normal human serum as a complement source, positive C3 and C4 staining were also evident. When purified IgG of normal human serum was used in place of pemphigus IgG, similar immunofluorescence staining was not observed. Further evidence for complement fixation in vitro by pemphigus antibodies was obtained using organ cultures. Organ culture of normal human skin and monkey esophageal mucosa cultured in purified pemphigus IgG showed intercellular substance binding of IgG. No binding was observed when normal IgG was substituted for pemphigus IgG. Additional organ culture sections were then treated with complement (fresh normal human serum) and tested by in vitro complement staining. Fixation of Clq, C4, and C3 was noted in intercellular substance areas of organ cultured skin and mucosa incubated with pemphigus IgG but not those incubated with normal IgG. Prior treatment of pemphigus IgG organ cultured skin sections with unlabeled anti-C3, blocked positive C3 staining. These results suggest that some pemphigus antibodies are capable of activating complement in vitro.

Animals↗
PubMed1984

Bullous dermatoses.

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Bibliographies as Topic↗
PubMed1983

Adaptation of the Ngo-Lenhoff peroxidase assay for solid phase ELISA.

A modification of the Ngo-Lenhoff peroxidase assay has been developed. By this method, peroxidase is detectable at 5 fmoles of peroxidase per ml. The assay is easy to perform and the reagents are inexpensive. We have modified the buffer by the addition of citric acid and sodium azide to reduce background color development and to inhibit the activity of catalase, respectively. Production of the indamine dye by the peroxidase reaction is rapid but it may be stopped by lowering the pH to 3.0. The pH change of 7.0 to 3.0 is accompanied by a color change from purple-blue to blue and a shift in the maximum absorbance from 590 nm to 595 nm. The sensitivity of the assay was unaffected by these modifications.

Binding, Competitive↗
PubMed1983

Bullous pemphigoid: a cause of peripheral blood eosinophilia.

A retrospective study demonstrated that fourteen of twenty-eight patients (50%) with clinical, histologic, and immunofluorescent findings of bullous pemphigoid had peripheral blood eosinophilia. Blood eosinophilia ranged from 5% to 43% when first tested, with increase in one patient to 56% during treatment. The pathophysiologic cause of blood eosinophilia in bullous pemphigoid is discussed with its relationship to previously demonstrated elevations of IgE and eosinophilic chemotactic factor of anaphylaxis (ECF-A) in serum and blister fluid. Peripheral blood eosinophilia was a common finding in our group of patients, and bullous pemphigoid should be included in the differential diagnosis of bullous skin conditions with eosinophilia.

Eosinophilia↗
PubMed1982

Leukocytoclastic vasculitis. A cutaneous expression of immune complex disease.

Thirty-nine patients with clinical, histologic, and immunofluorescence evidence of leukocytoclastic (necrotizing) vasculitis were studied for the presence of circulating immune complexes. These patients were selected prospectively during a three-year interval from patients seen in a dermatology clinic. Clinical and serologic data are summarized and representative cases are presented. This large series of patients with leukocytoclastic vasculitis emphasizes both the frequency of this disorder and the varied disease settings within which it may manifest. The immunopathologic data presented support an immune complex-mediated pathogenesis for this disease process.

Adolescent↗