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Cornified Envelopes (cornified + envelope)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Deletion of the late cornified envelope genes, LCE3C and LCE3B, is associated with rheumatoid arthritis

ARTHRITIS & RHEUMATISM, Issue 5 2010
Elisa Docampo
Objective The risk of rheumatoid arthritis (RA) is increased in the offspring of individuals affected with various autoimmune disorders, including psoriasis. Recently, the deletion of 2 genes from the late cornified envelope (LCE) gene cluster, LCE3C and LCE3B, has been associated with psoriasis in several populations. The purpose of this study was to assess whether this polymorphic gene deletion could also be involved in susceptibility to RA. Methods We tested for association between the LCE3C_LCE3B copy number variant and a single-nucleotide polymorphism in strong linkage disequilibrium with this variant (rs4112788) and RA in 2 independent case,control data sets (197 and 400 samples from patients with RA, respectively, and 411 and 567 samples from control subjects, respectively), collected at 4 Spanish hospitals. All samples were directly typed for presence of the LCE3C_LCE3B deletion (LCE3C_LCE3B- del) by polymerase chain reaction, and association analysis was performed using the SNPassoc R package. Results An association of homozygosity for the LCE3C_LCE3B -del and rs4112788 C allele with the risk of RA was observed in the first data set and was replicated in an independent case,control set. A combined analysis showed an overall P value of 0.0012 (odds ratio [OR] 1.45, 95% confidence interval [95% CI] 1.16,1.81) for association of the LCE3C_LCE3B- del. When the analysis was stratified for serologic data, we observed association in anti,cyclic citrullinated peptide (anti-CCP),positive patients (P = 0.012, OR 1.51 [95% CI 1.09,2.13]) but not in anti-CCP,negative patients. Conclusion We have identified an association between the LCE3C_LCE3B -del and RA, and we have verified a pleiotropic effect of a common genetic risk factor (LCE3C_LCE3B- del) for autoimmune diseases that is involved in both psoriasis and RA. [source]

Carbohydrate expression and modification during keratinocyte differentiation in normal human and reconstructed epidermis

EXPERIMENTAL DERMATOLOGY, Issue 5 2003
Bruno Méhul
Abstract:, Using fluorescein isothiocyanate (FITC)-labeled lectins we were able to demonstrate the presence of specific carbohydrate moieties in normal human and reconstructed epidermis. Evidence is provided that in both cases the strongly reduced lectin staining at the level of the stratum corneum is the result of a hindered accessibility of the lectins in this lipid-rich hydrophobic environment. Isolated corneocytes and purified cornified envelopes (CEs) exhibited clearly glycosylated structures reacting with distinct lectins. The presence of glycosidase activity, particularly in the upper layers of the epidermis characterized by an acidic environment (pH 5.5), indicates that modifications of the sugar residues might be important in epidermal homeostasis, barrier behavior and desquamation. Absent or strongly reduced glycosidase activity in the stratum corneum of reconstructed epidermis with an impaired pH gradient could be in part responsible for the reduced barrier function and the lack of desquamation in this model. [source]

Transglutaminase 1-deficient recessive lamellar ichthyosis associated with a LINE-1 insertion in Jack Russell terrier dogs

BRITISH JOURNAL OF DERMATOLOGY, Issue 2 2009
K.M. Credille
Summary Background, Congenital, nonepidermolytic cornification disorders phenotypically resembling human autosomal recessive ichthyosis have been described in purebred dog breeds, including Jack Russell terrier (JRT) dogs. One cause of gene mutation important to humans and dogs is transposon insertions. Objectives, To describe an autosomal recessive, severe nonepidermolytic ichthyosis resembling lamellar ichthyosis (LI) in JRT dogs due to insertion of a long interspersed nucleotide element (LINE-1) in the transglutaminase 1 (TGM1) gene. Methods, Dogs were evaluated clinically, and skin samples were examined by light and electron microscopy. Phenotypic information and genotyping with a canine microsatellite marker suggested TGM1 to be a candidate gene. Genomic DNA samples and cDNA generated from epidermal RNA were examined. Consequences of the mutation were evaluated by Western blotting, quantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme activity from cultured keratinocytes. Results, Affected dogs had generalized severe hyperkeratosis. Histological examination defined laminated to compact hyperkeratosis without epidermolysis; ultrastructurally, cornified envelopes were thin. Affected dogs were homozygous for a 1980-bp insertion within intron 9 of TGM1. The sequence of the insertion was that of a canine LINE-1 element. Quantitative RT-PCR indicated a significant decrease in TGM1 mRNA in affected dogs compared with wild-type. TGM1 protein was markedly decreased on immunoblotting, and membrane-associated enzyme activity was diminished in affected dogs. Conclusions, Based on morphological and molecular features, this disease is homologous with TGM1-deficient LI in humans, clinically models LI better than the genetically modified mouse and represents its first spontaneous animal model. This is the first reported form of LI due to transposon insertion. [source]

Cross-linked envelopes in nail plate in lamellar ichthyosis

BRITISH JOURNAL OF DERMATOLOGY, Issue 5 2003
R.H. Rice
Summary Background Corneocytes of the nail plate, like those of the stratum corneum, generate cornified envelopes (CEs) of cross-linked protein that can be visualized readily after removal of non-cross-linked protein by detergent extraction. Defective CE formation occurs in epidermal scale and hair in transglutaminase 1 (TGM1)-negative lamellar ichthyosis (LI) and has been proposed as a diagnostic aid for this syndrome. Objectives (i) To ascertain whether TGM1 is important for CE formation in nail; (ii) to characterize CE abnormalities occurring in LI that may be distinguished from other types of inherited ichthyosis when nail samples are subjected to detergent extraction; and (iii) to evaluate the utility of nails as a diagnostic aid for LI. Methods Nail samples were provided by nine patients previously classified as having TGM1-negative LI, four with other types of ichthyotic conditions and six normal controls. Samples were extracted extensively in sodium dodecyl sulphate under reducing conditions and examined by light and electron microscopy. Results After extraction, defective CE cross-linking was visualized in epidermal corneocytes from seven of nine patients exhibiting TGM1-negative LI, whereas nail samples from patients with the other syndromes were normal. The defects in CE structure resembled those recently reported for LI scale, although in some cases residual CE and CE-associated structures were present. Conclusions Despite the paucity of clinical nail symptoms in LI, TGM1 activity is important for generation of normal CE in nail plate, consistent with its importance in protein cross-linking in interfollicular epidermis and hair. Lack of this activity leads to a strikingly aberrant appearance of CE in LI nail after detergent extraction that is evident ultrastructurally in a large majority of cases. Nail envelopes therefore could provide a useful diagnostic tool in distinguishing LI from other ichthyoses with overlapping clinical features. [source]