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Y Sarret

Publications and source records attributed to Y Sarret.

24 records · Page 2Linked to original sources
PubMed1990

GP37 is different from filaggrin.

The identity of two differentiation markers of human epidermis, filaggrin and a Concanavalin A (Con-A) reactive glycoprotein of 37 kD, has been studied. Human epidermis was extracted in Nonidet P-40 buffer, and the soluble proteins were separated by two-dimensional electrophoresis. Con-A reactive glycoproteins were identified by incubating gels with iodinated lectin followed by autoradiography. Identical, parallel gels were electrophoretically transferred to nitrocellulose paper and filaggrin-related molecules labeled by the specific monoclonal antibody AKH1. We found that the 37-kD Con-A reactive component was resolved by two-dimensional gel electrophoresis into several glycoproteins and that the lectin Con-A does not bind to filaggrin. Under these conditions, the anti-GP37 serum failed to identify any component. However, when applied to human keratinocyte culture extract, AKH1 and the anti-GP37 serum reacted in a similar way. These data show 1) that the 37-kD band is not homogeneous but contains distinct markers of differentiation (filaggrin and Con-A reactive glycoproteins) and 2) that the GP37 antibody's specificity is for the filaggrin precursor.

Antibodies, Monoclonal↗
PubMed1989

Bullous pemphigoid and cicatricial pemphigoid: immunoblotting detection of involved autoantigens.

Bullous pemphigoid (BP) and cicatricial pemphigoid (CP) are subepidermal bullous autoimmune diseases which have distinct clinical features but identical immunological status. In order to determine whether these diseases could be dissociated on the basis of qualitative differences in serum antibodies to basement membrane zone (BMZ) antigens, the reactivity of sera from 7 CP and 29 BP patients with proteins extracted from normal human epidermal sheets (containing most of the lamina lucida components) was analysed using immunoblotting and compared to that of 10 normal sera. 20 out of the 29 BP sera contained antibodies recognizing one or several protein(s) of 240, 200, 180 and 165 kD molecular weight (MW). Antibodies in 4 out 7 CP sera specifically reacted with one or two polypeptides of 240 and 120 kD MW. These data confirm the heterogeneity of BP antigens and show the presence in CP of a novel 120 kD MW polypeptide which is found only in CP but not in BP. Taken together these findings demonstrate that in BP and CP, autoantibodies are directed to both common and specific BMZ antigens, their physiopathological significance need to be understood.

Adult↗
PubMed1989

[Filaggrin].

Cells in the granular layer of mammalian epidermis contain densely staining bodies called keratohyalin granules. Two types of granules are identified. Larger ones contain phosphorus and consist largely of an unusually histidine rich protein. This protein has a high molecular weight and contains a large fraction of basic aminoacids. However it has a neutral isoelectric point due to extensive phosphorylations. This histidine rich protein undergoes modifications during terminal differentiation, especially when the keratohyalin granules disperse as the granular cells differentiate into the overlying cornified cells. At this point it is dephosphorylated and partially proteolyzed to form lower molecular weight highly basic histidine rich proteins. These cationic molecules aggregate in vitro with keratin intermediate filaments, forming well ordered macrofibrils whose structure resembles the keratin pattern seen in the lower cornified layers. For this reason the name filaggrin is used for these proteins. The high molecular weight precursor is called profilaggrin. Filaggrins are species-distinct products and consist of a number of isoelectric variants. It is established that the filaggrin precursor is composed of tandemly linked multiple copies of filaggrin domains interspersed with short linker peptides. Two functions are proposed for the filaggrin. The first one, based on its interaction with keratin fibres in vitro, is to form the interfilamentous matrix seen in the lower stratum corneum. The second one is to generate a concentrated pool of free aminoacids and derivatives, allowing the stratum corneum to remain hydrated at low environmental humidities. These functions represent sequential rather alternative roles. Epidermal diseases and in vitro cultures illustrate the clear-cut relations between epidermal keratinization and differentiation and the histidine rich proteins pathway.

Animals↗
PubMed1989

[New paraclinical approaches for the diagnosis of autoimmune bullous diseases].

In this paper, four new techniques for the fine diagnosis of autoimmune blistering diseases have been reviewed: immunoelectron microscopy, immunoblotting, immunofluorescence on salt-split-skin substrate and immunoprecipitation. They have allowed a better understanding of the pathogenesis of various diseases such as bullous pemphigoid and epidermolysis bulosa acquisita. Indeed the antigens have been precisely localized at the ultrastructural level and their biochemical nature determined; moreover their synthesis has been studied using cell cultures. The next step will use the molecular biology in order to ultimately define and understand these diseases.

Autoantigens↗
PubMed1987

[Treatment of bacterial infections by ofloxacin. 42 cases].

Fourty-two patients with 44 infective sites were treated with ofloxacin alone (22) or associated with an other antibiotic (20). Thirty-five patients (83%) and 37 infective localisations (84%) were cured. The treatment efficacy was similar for ofloxacin alone or associated, and for treatments given with first or second intent. All non-documented infections were cured. Two of the 4 failures were pneumococcal. So, the non-documented infections, the genital and urinary tract infections, the pulmonary infections (second intent) and osteitis seem to be the best indications of ofloxacin therapy.

Adult↗