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J R Stanley

Publications and source records attributed to J R Stanley.

At least 55 records · Page 3Linked to original sources
PubMed1995

Defective cell-cell adhesion in the epidermis.

The disastrous effects of loss of epidermal cell adhesion are epitomized by the life-threatening blistering skin diseases pemphigus foliaceus and pemphigus vulgaris. Clinical and experimental observations show that loss of cell adhesion is induced by these patients' autoantibodies. Pemphigus foliaceus antigen is desmoglein 1 (dsg-1), a desmosomal transmembrane glycoprotein limited in distribution to stratified squamous epithelia. It is linked to plakogoblin, a desmosomal plaque protein. Molecular cloning has shown that desmogleins are members of the cadherin gene superfamily. The originally described cadherins (e.g. E-cadherin) are transmembrane, calcium-dependent, homophilic adhesion molecules. Pemphigus vulgaris antigen is a 130 kDa glycoprotein also linked to plakoglobin. Molecular cloning has shown that pemphigus vulgaris antigen is also a desmoglein, dsg-3. Antibodies against pemphigus vulgaris antigen subdomains homologous to the binding subdomains of classical cadherins cause loss of epidermal cell adhesion, which suggests that desmogleins mediate adhesion, although direct evidence for this is lacking. The extracellular domain of pemphigus vulgaris antigen cannot substitute in function for that of E-cadherin. Future studies should address the cell biological function of desmogleins.

Animals↗
PubMed1995

Effects of intracervical prostaglandin E2 on fetal heart rate and uterine activity patterns in the presence of oligohydramnios.

OBJECTIVE: Our purpose was to compare fetal heart rate patterns and uterine activity before and after preinduction prostaglandin E2 administration in the presence or absence of oligohydramnios. STUDY DESIGN: In a retrospective case-controlled review we examined cases in which prostaglandin E2 (Prepidil) was inserted intracervically for gravid women requiring an induction of labor in the presence of either oligohydramnios (amniotic fluid index < or = 5.0) or adequate fluid (amniotic fluid index 5.1 to 23.9). Uterine activity and fetal heart rate tracings that were begun 1 hour before and continued for 6 hours after dosing were interpreted without knowledge of amniotic fluid volume. RESULTS: Cases in the oligohydramnios (n = 51) and adequate fluid (n = 49) groups were the same for maternal age, race, parity, gestational age, and predose Bishop score. Patients with oligohydramnios had more high-amplitude contractions in the first hour after dosing (9.0 +/- 1.2 vs 6.1 +/- 0.9, p < 0.05), but there were no significant differences in the frequency or duration of contractions during the subsequent 5 hours. Uterine hyperstimulation was not seen, and there were no differences in the frequency of variable or late fetal heart rate decelerations. CONCLUSION: For pregnancies undergoing preinduction cervical ripening with intracervical prostaglandin E2, the presence of oligohydramnios was not associated with a greater risk of fetal heart rate decelerations, although contractions were more common during the first hour after dosing.

Adult↗
PubMed1995

Intracellular domain of desmoglein 3 (pemphigus vulgaris antigen) confers adhesive function on the extracellular domain of E-cadherin without binding catenins.

For the extracellular (EC) domain of E-cadherin to function in homophilic adhesion it is thought that its intracytoplasmic (IC) domain must bind alpha- and beta-catenins, which link it to the actin cytoskeleton. However, the IC domain of pemphigus vulgaris antigen (PVA or Dsg3), which is in the desmoglein subfamily of the cadherin gene superfamily, does not bind alpha- or beta-catenins. Because desmogleins have also been predicted to function in the cell adhesion of desmosomes, we speculated that the PVA IC domain might be able to act in a novel way in conferring adhesive function on the EC domain of cadherins. To test this hypothesis we studied aggregation of mouse fibroblast L cell clones that expressed chimeric cDNAs encoding the EC domain of E-cadherin with various IC domains. We show here that the full IC domain of PVA as well as an IC subdomain containing only 40 amino acids of the PVA intracellular anchor (IA) region confer adhesive function on the E-cadherin EC domain without catenin-like associations with cytoplasmic molecules or fractionation with the cell cytoskeleton. This IA region subdomain is evolutionarily conserved in desmogleins, but not classical cadherins. These findings suggest an important cell biologic function for the IA region of desmogleins and demonstrate that strong cytoplasmic interactions are not absolutely necessary for E-cadherin-mediated adhesion.

Amino Acid Sequence↗
PubMed1995

Pemphigus sera recognize conformationally sensitive epitopes in the amino-terminal region of desmoglein-1.

To identify regions of the Desmoglein-1 (Dsg1) extracellular domain that are targeted by pemphigus antisera, cDNA sequences encoding various regions of the Dsg1 extracellular domain were ligated to sequences encoding the E-cadherin extracellular anchor and transmembrane and cytoplasmic domains. These constructs were then expressed in mammalian cells, and pemphigus sera were tested for the ability to recognize the Dsg1 extracellular domains. When analyzed by immunoblot, very few pemphigus foliaceus sera recognized the Dsg1 domains. To determine whether pemphigus sera recognize non-denatured Dsg1 domains, constructs were expressed in cultured cells and tested for reactivity with pemphigus sera using live-cell immunofluorescence. The pemphigus foliaceus sera reacted strongly with the Dsg1 extracellular domain by live-cell immunofluorescence and recognized predominantly the amino-terminal region of the Dsg1 extracellular domain. In addition, sera from patients with pemphigus vulgaris also demonstrated strong reactivity with the Dsg1 extracellular domain when tested using live-cell immunofluorescence. In contrast, sera from normal human controls and sera from bullous pemphigoid patients did not react with the Dsg1 extracellular domain. These data indicate that both pemphigus foliaceus and pemphigus vulgaris sera react with conformationally sensitive epitopes in the amino-terminal region of Dsg1.

Base Sequence↗
PubMed1995

Plakoglobin binding by human Dsg3 (pemphigus vulgaris antigen) in keratinocytes requires the cadherin-like intracytoplasmic segment.

Desmogleins are transmembrane desmosomal cadherins. Two desmogleins, Dsg3 and Dsg1, have been shown to bind plakoglobin, an intracytoplasmic (IC) desmosomal plaque protein. This binding may be critical for desmosome assembly or stability. The IC domain of desmogleins consists of subdomains that are either desmoglein specific or homologous with the IC region of classical cadherins. Here we identify the domains of human Dsg3 that are critical for plakoglobin binding in human keratinocytes. We constructed eukaryotic expression vectors containing chimeric cDNAs that encode the extracellular domain of mouse E-cadherin (Ecad) with the transmembrane and IC domains of Dsg3, with increasing truncations eliminating various IC subdomains from the carboxy-terminus. These constructs were used for transient transfection of HaCaT cells. Extracts were subjected to immunoprecipition with an anti-mouse Ecad antibody (that does not precipitate human Ecad), thus precipitating the chimeric protein and any tightly associated plakoglobin. Co-precipitation of plakoglobin was confirmed by immunoblotting. These data show that the desmoglein-specific IC subdomains are not necessary for plakoglobin binding, but the carboxy-terminal 87 amino acids of the IC-cadherin-like segment subdomain are critical. Finally, we confirmed these results outside cells with in vitro transcription and translation, which also demonstrates that the Dsg3-plakoglobin interaction is direct and does not depend on other cellular factors. These results underscore the importance of a region, highly conserved in all desmogleins, in the carboxy terminus of the IC-cadherin-like subdomain for the localization of plakoglobin to desmosomes.

Amino Acid Sequence↗
PubMed1995

A statewide, toll-free telephone service to improve obstetric care.

The University of Oklahoma Health Sciences Center began in 1993 to provide a statewide, toll-free telephone service for pregnancy counseling to primary care physicians. The service was available 24 hours each day, and responses were made by the on-call maternal-fetal medicine specialist. This report summarizes our first full year of operation. Inquiries came from 34 (63%) of the state's 54 counties having physicians who provide obstetric care. One hundred twenty-eight physicians made 523 inquiries (median 3, range 1-15). Information was sought about prenatal genetic disorders, risks from drugs, exposure to infection, environmental hazards, and active obstetric or medical complications. Funds from targeted ultrasounds, genetic amniocenteses, more detailed counselling, and maternal transfers provided support for this expanding educational resource.

Female↗
PubMed1994

Extracellular domain of pemphigus vulgaris antigen (desmoglein 3) mediates weak homophilic adhesion.

Pemphigus vulgaris antigen is in the cadherin supergene family. We hypothesized that the extracellular domain of pemphigus vulgaris antigen might mediate homophilic cell adhesion because 1) the originally described cadherins (e.g., E-cadherin) mediate this type of adhesion, 2) pemphigus vulgaris antigen is localized in desmosomes that are cell adhesion junctions, and 3) autoantibodies in pemphigus vulgaris patients cause loss of cell adhesion. To test this hypothesis we used a system developed for E-cadherin that, when transfected into L cells (mouse fibroblasts), has been shown to cause aggregation. Because this aggregation requires the cytoplasmic domain of E-cadherin to bind to catenins, we made a chimeric cDNA construct that encodes the extracellular domain of pemphigus vulgaris antigen and the cytoplasmic domain of E-cadherin. Analysis by immunofluorescence and flow cytometry with pemphigus vulgaris sera indicated that the pemphigus vulgaris antigen extracellular domain of this chimeric molecule (PVEC) was expressed on the cell surface of transiently transfected cells and permanently transfected L-cell clones. Immunoprecipitation of the chimeric molecule from extracts of these clones showed that the E-cadherin cytoplasmic domain bound catenins. Surprisingly, these L-cell clones displayed only slight aggregation compared to an L-cell clone transfected with E-cadherin. This weak aggregation was, however, specific and homophilic, as determined by cell sorting of only PVEC transfectants into aggregates from mixtures of PVEC and neomycin resistance gene transfectants, one of which was labeled with a fluorescent dye. We conclude that the extracellular domain of pemphigus vulgaris antigen mediates weak homophilic adhesion and is not interchangeable in function with the extracellular domain of E-cadherin.

Animals↗
PubMed1994

Pemphigus vulgaris antigen lacks biochemical properties characteristic of classical cadherins.

Pemphigus vulgaris antigen (PVA) is a member of the desmoglein subfamily of the cadherin supergene family. PVA has homology to the classical cadherins (e.g., E-cadherin), both in its extracellular and cytoplasmic domains. Classical cadherins possess certain well-defined and characteristic biochemical properties of both domains. The cytoplasmic domain binds alpha-, beta-, and gamma-catenins. The extracellular domain is protected by calcium from degradation by trypsin. In this study we show that PVA does not share these characteristic biochemical features. Immunoprecipitation of E-cadherin and PVA from human keratinocytes shows that under the same conditions in which the catenins co-precipitate with E-cadherin, only plakoglobin (which co-migrates with gamma-catenin) co-precipitates with PVA. Treatment of keratinocytes with 0.01% trypsin in 1 mM calcium (T/C) does not degrade the extracellular region of E-cadherin, but does partially degrade that of PVA. This increased T/C susceptibility of PVA is not due to its cytoplasmic domain, as the same sensitivity of the extracellular domain of PVA to T/C was observed in L cell clones transfected with a chimeric cDNA that encoded for the extracellular domain of PVA and the cytoplasmic domain of E-cadherin. These data demonstrate that although the desmogleins and classical cadherins share striking amino acid homologies in both the cytoplasmic and extracellular domains, they do not exhibit identical biochemical properties and, by extension, may not subserve identical cell biologic functions.

Amino Acid Sequence↗
PubMed1994

Extracellular domain of pemphigus vulgaris antigen (desmoglein 3) mediates weak homophilic adhesion.

Pemphigus vulgaris antigen is in the cadherin supergene family. We hypothesized that the extracellular domain of pemphigus vulgaris antigen might mediate homophilic cell adhesion because 1) the originally described cadherins (e.g., E-cadherin) mediate this type of adhesion, 2) pemphigus vulgaris antigen is localized in desmosomes that are cell adhesion junctions, and 3) autoantibodies in pemphigus vulgaris patients cause loss of cell adhesion. To test this hypothesis we used a system developed for E-cadherin that, when transfected into L cells (mouse fibroblasts), has been shown to cause aggregation. Because this aggregation requires the cytoplasmic domain of E-cadherin to bind to catenins, we made a chimeric cDNA construct that encodes the extracellular domain of pemphigus vulgaris antigen and the cytoplasmic domain of E-cadherin. Analysis by immunofluorescence and flow cytometry with pemphigus vulgaris sera indicated that the pemphigus vulgaris antigen extracellular domain of this chimeric molecule (PVEC) was expressed on the cell surface of transiently transfected cells and permanently transfected L-cell clones. Immunoprecipitation of the chimeric molecule from extracts of these clones showed that the E-cadherin cytoplasmic domain bound catenins. Surprisingly, these L-cell clones displayed only slight aggregation compared to an L-cell clone transfected with E-cadherin. This weak aggregation was, however, specific and homophilic, as determined by cell sorting of only PVEC transfectants into aggregates from mixtures of PVEC and neomycin resistance gene transfectants, one of which was labeled with a fluorescent dye. We conclude that the extracellular domain of pemphigus vulgaris antigen mediates weak homophilic adhesion and is not interchangeable in function with the extracellular domain of E-cadherin.

Animals↗
PubMed1994

Pemphigus vulgaris antigen is a desmosomal desmoglein.

Because pemphigus vulgaris antigen (PVA) is homologous to desmogleins which are in desmosomes, we asked whether PVA is also localized to desmosomes. Immunogold electron microscopy was used to localize binding of PV antibodies. Rabbit antibodies raised against fusion proteins containing the extracellular portion of PVA bound to desmosomes of cultured keratinocytes. PV patient serum affinity-purified on one of these fusion proteins and injected into neonatal mice localized to separating desmosomes. These results show that PVA belongs to the desmoglein subfamily of cadherins according to sequence, localization and, presumably, function.

Cadherins↗
PubMed1994

Recurrence of pemphigus vulgaris associated with interleukin 2 therapy.

BACKGROUND: Immunotherapy with recombinant interleukin 2 may result in regression of metastatic cancer, particularly malignant melanoma and renal cell carcinoma. OBSERVATIONS: We describe a patient who received interleukin 2 immunotherapy for metastatic renal cell carcinoma. After his second course of treatment, he developed a recurrence of pemphigus vulgaris that had been in remission for 10 years. CONCLUSIONS: Interleukin 2 therapy may be associated with recurrence of an autoimmune disease, perhaps because of its ability to stimulate autoantibody production.

Aged↗
PubMed1994

Magnetic resonance imaging in evaluation of a second-trimester ovarian twin pregnancy.

BACKGROUND: Ovarian pregnancy presents with abdominal pain and menstrual irregularities, and usually results in hemorrhage and hemoperitoneum in the first trimester. We describe the first case of a twin ovarian pregnancy diagnosed in the second trimester. Magnetic resonance imaging (MRI) was used in the preoperative evaluation of this patient. CASE: A woman presented at 19 weeks' gestation with abdominal pain and irregular bleeding. Her hemoglobin level was 5.9 g/dL, as compared to 10.8 g/dL in early pregnancy. Ultrasound showed a twin gestation with a mass anterior to the pregnancy, thought to be a placenta percreta or a hemorrhagic leiomyoma. An MRI was suspicious for an extrauterine pregnancy, showing the uterus displaced anteriorly by the pregnancy mass. Laparotomy revealed a hemoperitoneum and right twin ovarian pregnancy. A right salpingo-oophorectomy was performed. Pathology confirmed the diagnosis. CONCLUSION: Although ultrasound is the primary technique of imaging the pelvis during pregnancy, MRI should be considered when the ultrasound findings are limited or confusing.

Adult↗
PubMed1993

Adhesion of epidermal Langerhans cells to keratinocytes mediated by E-cadherin.

Langerhans cells (LC) are the principal accessory cells present in epidermis. Because LC have limited capacity for self-renewal, epidermis is continually repopulated by as-yet uncharacterized bone marrow-derived LC progenitors. In addition, although LC persist in epidermis for extended periods, LC are induced to migrate from skin to regional lymph nodes after antigen exposure. To begin to elucidate mechanisms involved in LC trafficking, we characterized LC-keratinocyte (KC) interactions. Here we report that fresh murine LC express cadherins, and that LC adhere to KC in vitro through E-cadherin. Cultured LC (which may bear a phenotypic and functional relationship to LC that have migrated to lymph nodes) express lower levels of E-cadherin and exhibit decreased affinity for KC. These results suggest that expression of E-cadherin by LC promotes persistence of these cells in epidermis, and that cadherins may play important and unanticipated roles in interactions between leukocytes and epithelia.

Animals↗
PubMed1993

Pemphigus vulgaris antigen, a desmoglein type of cadherin, is localized within keratinocyte desmosomes.

Pemphigus vulgaris antigen (PVA) is a member of the desmoglein subfamily of cadherin cell adhesion molecules. Because autoantibodies in this disease cause blisters due to loss of epidermal cell adhesion, and because desmoglein is found in the desmosome cell adhesion junction, we wanted to determine if PVA is also found in desmosomes. By immunofluorescence, PV IgG bound, in a dotted pattern, to the cell surface of cultured human keratinocytes induced to differentiate with calcium, suggesting junctional staining. However, by preembedding, immunogold electron microscopic studies only slight labeling could be detected in desmosomes, presumably because of difficulty in gold penetration of intact desmosomes. We therefore treated the keratinocytes with 0.01% trypsin in 1 mM calcium, conditions known to preserve cadherin antigenicity but that caused slight separation of desmosomes, before immunogold staining. In this case there was extensive labeling of the extracellular part of desmosomes but not of the interdesmosomal cell membrane which was stained with anti-beta 2-microglobulin antibodies. To confirm the specificity of this binding we showed that antibodies raised in rabbits against the extracellular portions of PVA also bound desmosomes in these cultures. In intact mouse epidermis we could also show slight, but specific, immunogold desmosomal labeling with PV IgG. Furthermore, neonatal mice injected with PV IgG affinity purified on PVA showed desmosomal separation with the IgG localized to desmosomal cores. These results indicate that PVA is organized and concentrated within the desmosome where it presumably functions to maintain the integrity of stratifying epithelia.

Animals↗
PubMed1993

Erythema annulare-like acantholytic dermatosis (EAAD): nonbullous pemphigus or a new entity?

This article describes a case of unusual annular erythema-like dermatosis, with histological features of pemphigus foliaceus (subcorneal acantholysis) and IgG antibodies in circulation and bound in vivo to the keratinocyte surface. The reactivity of the antibodies, restricted to human squamous epithelium, was unique, differing from that of all known forms of pemphigus. This also was confirmed by immunoprecipitation. The problem is that these circulating antibodies could be missed if not determined on human substrate. It is to be established whether such cases present a new type of pemphigus or a unknown dermatosis with an autoimmune response of a pemphigus type.

Acantholysis↗