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Pascal Joly

Publications and source records attributed to Pascal Joly.

At least 19 recordsLinked to original sources

A truncated alternative spliced isoform of human desmoglein 1 contains a specific T cell epitope binding to the pemphigus foliaceus-associated HLA class II DRbeta1*0102 molecule.

Desmogleins (Dsg) are transmembrane glycoproteins of the desmosome that allow a cell-cell adhesion between keratinocytes and comprise four different isoforms (Dsg1 to Dsg4). Two Dsg are targeted by pathogenic autoantibodies produced in the course of autoimmune bullous skin diseases, Dsg1 in pemphigus foliaceus (PF), and Dsg3 and Dsg1 in pemphigus vulgaris. The genetic susceptibility to PF is associated with certain HLA class II alleles, which are thought to participate in disease pathogenesis through their capacity to accommodate autoantigen-derived peptides and present them to autoreactive T cells. So far, a unique isoform of Dsg1 has been described in humans, which includes several immunodominant T cell epitopes. In this study, we describe an alternative transcript of DSG1, which contains a 101-bp insertion corresponding to the 3' end of DSG1-intron 6 and introducing a stop codon in the nucleotide sequence. This alternative transcript leads to the synthesis of a truncated isoform of Dsg1 expressed in normal human epidermis. This isoform bears a specific peptide sequence that binds to the PF-associated HLA class II DRbeta1*0102 molecule as shown in a HLA-DR peptide-binding assay, and induces PF T cell proliferation. These data provide an illustration of an autoantigen encoded by alternative spliced transcript that may participate in the pathogenesis of the disease by bearing PF-associated HLA class II restricted-epitope.

Alternative Splicing↗

Proteomic analysis of the autoantibody response following immunization with a single autoantigen.

In most autoimmune diseases, the autoantibody response is directed against several antigens of the target organ whose identification is crucial for understanding the physiopathological process. Thus, technologies allowing a characterization of the whole autoantibody pattern of both human and experimental autoimmune diseases are required. Here we have used immunoproteomic analysis of human epidermal extracts to characterize the diversity of the anti-desmosome antibody response induced in normal mice immunized with desmoglein 1, the major autoantigen of pemphigus foliaceus, an autoimmune blistering skin disease. In particular, this analysis enables us to characterize the binding properties of anti-desmosome mAbs derived from these mice and to show that the autoantibody response induced upon immunization with a single autoantigen targets different epidermal autoantigens with a pattern similar to that observed in certain variety of human pemphigus.

Amino Acid Sequence↗

The use of methotrexate alone or in combination with low doses of oral corticosteroids in the treatment of alopecia totalis or universalis.

Treatment of severe alopecia areata (AA) remains difficult. To assess the tolerance and efficacy of methotrexate (MTX) in the treatment of severe long-term AA, we retrospectively evaluated 22 patients with AA totalis or universalis with a mean duration of 11.0 +/- 8.8 years who were treated with MTX either alone (n = 6) or associated with low doses of oral prednisone (n = 16). MTX was given at an initial weekly dosage of 15 mg (n = 3), 20 mg (n = 9), or 25 mg (n = 10). Oral prednisone was given at an initial dosage of 10 mg/d in one patient and 20 mg/d in 15 patients. In all, 14 patients (64%) achieved a total recovery including 3 of 6 patients treated by MTX alone and 11 of 16 who had received the combined treatment. Of the 14 patients who had total hair regrowth, 6 stopped MTX. In all, 3 patients maintained hair regrowth and 3 relapsed. Retreatment of these 3 patients by MTX resulted again in hair regrowth. No severe side effect was observed. Although limited by its uncontrolled character, this study shows that MTX and low doses of oral corticosteroids may be an effective and well-tolerated treatment for severe types of AA.

Administration, Oral↗

Immunogenetics of pemphigus: an update.

Pemphigus are rare but informative models of organ-specific autoimmune diseases, resulting from the interplay of environmental, genetic and stochastic factors. There are many arguments to consider that pemphigus have a genetic basis involving, as many other autoimmune diseases, several different genes with additive or synergistic effects. So far, the unique strategy used to identify the contributive loci has been direct analysis of candidate genes through conventional case-control association studies. The major histocompatibility complex in particular the class II locus was demonstrated to be associated with pemphigus with a high rate of replicability. The progresses in the understanding of pemphigus physiopathology and the development of new molecular tools offer new perspectives to unveiled the genetic basis of this group of autoimmune blistering diseases, as shown by recent studies of candidate genes expressed at different levels of the autoimmune process.

Animals↗

[Bullous pemphigoid].

Bullous pemphigoid (BP) is the most frequent autoimmune blistering skin disease of the elderly. It is mediated by circulating antibodies directed against two hemidesmosomal proteins of the dermal epidermal junction: BPAG1 and BPAG2. Clinical features consist of pruritus and tense blisters usually surrounded by erythema. Blisters sometimes evolve to erosions, become haemorrhagic or even large erosive areas. Lesions heal without scarring. Lesions are symmetrically located on the thighs, legs, trunck and arms. Mucous membranes are usually uninvolved. Histological examination of a skin biopsy specimen shows a subepidermal blister with eosinophils within the blister and the superficial dermis. Direct immunofluorescence shows linear IgG and/or C3 deposits along the dermal epidermal junction. In France and in Europe, most patients are now treated using topical steroid therapy (clobetasol propionate).

Aged↗

Clonal T cells in the blood of patients with systemic sclerosis.

BACKGROUND: It has been suggested that clonal T cells may play a critical role in the pathogenesis of systemic sclerosis. OBSERVATIONS: A monoclonal population of T cells was found in blood samples from 13 (34%) of 38 consecutive patients with a definite diagnosis of systemic sclerosis who were prospectively examined by T-cell receptor gamma gene rearrangement using polymerase chain reaction analysis and denaturating gradient gel electrophoresis. In the healthy control group, the same type of examination revealed a monoclonal population of T cells in the blood samples from only 3 healthy subjects (4%)(odds ratio, 12.28; 95% confidence interval, 2.76-54.64; P = .001). Patients who had a circulating clonal population of T cells were older than those who did not (67 years vs 48 years; P = .04). There was a marked relationship between systemic sclerosis subtypes and the presence of a circulating clonal population of T cells. Twelve (43%) of 28 patients with limited cutaneous sclerosis exhibited a circulating clonal population of T cells, whereas only 1 (10%) of the 10 patients with diffuse cutanous sclerosis had evidence of T-cell clonality (P<.01). CONCLUSIONS: Clonally expanded T cells were more commonly detected in patients with limited cutaneous sclerosis than in those with diffuse cutaneous sclerosis, which is also in accordance with a possible role of clonal T cells in patients with limited cutaneous sclerosis.

Adult↗

Prediction of survival for patients with bullous pemphigoid: a prospective study.

OBJECTIVE: To identify the prognostic factors of bullous pemphigoid (BP). DESIGN: Prospective study of patients with BP included in a randomized, controlled trial. SETTING: Twenty dermatology departments in France. Patients One hundred seventy patients with BP initially treated with a 40-g/d dosage of clobetasol propionate cream (testing sample) and 171 patients initially treated with oral corticosteroids at a dosage of 0.5 or of 1.0 mg/kg per day, depending on the extent of BP (validation samples). MAIN OUTCOME MEASURES: The end point was overall survival during the first year after BP diagnosis. From the testing sample, associations of clinical and biological variables with overall survival were assessed using univariate and multivariate analyses. Selected predictors were included in a prognostic model. To verify that these predictors were not dependent on the treatment used, the model was then validated independently on the 2 series of BP patients treated with oral corticosteroids. RESULTS: Median age of the BP patients included in the testing sample was 83 years. The 1-year Kaplan-Meier survival rate was 74%. From univariate analysis, the main deleterious predictors were demographic factors (ie, older age and female sex), associated medical conditions (ie, cardiac insufficiency, history of stroke, and dementia), and low Karnofsky score, which is a measure of the patient's general condition. No factors directly related to BP, in particular extent of cutaneous lesions, were shown to be related to the patients' prognosis. From multivariate analysis, only older age (P = .02) and low Karnofsky score (P<.001) appeared independently predictive of death. From the Cox model including these 2 predictors, the predicted 1-year survival rates were 90% (95% confidence interval [CI], 85%-96%) for patients 83 years or younger with Karnofsky score greater than 40, 79% (95% CI, 69%-90%) for patients older than 83 years with Karnofsky score greater than 40, 65% (95% CI, 50%-86%) for patients 83 years or younger with Karnofsky score of 40 or less, and 38% (95% CI, 26%-57%) for patients older than 83 years with Karnofsky score of 40 or less. Kaplan-Meier survival distributions of patients from the validation samples appeared clearly separated according to these 4 categories and were in close agreement with corresponding predicted 1-year survival rates obtained from the testing sample. CONCLUSIONS: The prognosis of patients with BP is influenced by age and Karnofsky score. These predictors are easy to use and should facilitate the management of BP.

Administration, Oral↗

Treatment of early-stage mycosis fungoides with twice-weekly applications of mechlorethamine and topical corticosteroids: a prospective study.

OBJECTIVE: To determine if a therapeutic regimen of twice-weekly applications of mechlorethamine hydrochloride and betamethasone dipropionate cream is effective in the treatment of early-stage mycosis fungoides while increasing cutaneous tolerance. DESIGN: Prospective nonrandomized study conducted from November 1999 to November 2002. SETTING: Eleven university or hospital dermatology departments in France. PATIENTS: Sixty-four consecutive patients with newly diagnosed early-stage mycosis fungoides (stage IA, n = 33; stage IB, n = 26; stage IIA, n = 5). INTERVENTIONS: Patients were treated with twice-weekly applications of a 0.02% aqueous solution of mechlorethamine followed by an application of betamethasone cream during a 6-month period. MAIN OUTCOME MEASURES: The primary end point was the rate of complete response during the treatment. Secondary end points were mean delay to achieve complete response, rate of severe cutaneous reactions of intolerance, and rate of relapse after achieving complete response. RESULTS: Thirty-seven patients (58%) had a complete response after a mean +/- SD treatment duration of 3.6 +/- 2.5 months: 20 (61%) of 33 patients with stage IA disease, 15 (58%) of 26 patients with stage IB disease, and 2 (40%) of 5 patients with stage IIA disease. Eighteen patients (28%) developed severe cutaneous reactions of intolerance that necessitated treatment discontinuation. Relapse was observed in 17 patients (46%) after a mean +/- SD time of 7.7 +/- 6.5 months. CONCLUSIONS: A regimen of twice-weekly applications of mechlorethamine and betamethasone cream is an effective treatment for early-stage mycosis fungoides. The decreased frequency of applications provides an advantage to the patient by being easy to use with limited adverse effects.

Administration, Topical↗

Genetic factors in pemphigus.

Epidemiological studies performed in different ethnic populations and family studies, notably based on a partial phenotype of the autoimmune process, indicate that genetic factors are involved in the occurrence of pemphigus. However, the precise heritability remains uncertain in the absence of twin concordance rate studies. Among the different strategies available to identify genetic factors participating in autoimmune disease susceptibility, only population studies based on case-control design have been performed in pemphigus. These studies consistently showed that MHC locus, in particular HLA class II alleles, are associated with pemphigus vulgaris and pemphigus foliaceus. Other genes of the MHC locus may also participate in disease susceptibility as shown by studies using microsatellite markers across different regions of the MHC. It is likely that other non-MHC genes are involved in the pathogenesis of pemphigus. In particular, involvement of a polymorphic variant of desmoglein 1 gene was shown to be associated with pemphigus foliaceus and to interact in an epistatic manner with MHC class II genes to contribute to the autoimmune process. Other candidate genes to which a role can be assigned in the disease pathogenesis should be considered to design case-control or family-based association studies. Genome scan studies which require a large number of multiplex families to reach statistical power, should also be considered in the endemic form of pemphigus foliaceus because of the high number of familial cases.

Alleles↗

The role of topical corticosteroids in bullous pemphigoid in the elderly.

Bullous pemphigoid (BP) is the most common autoimmune blistering skin disease. Until recently the condition was treated with oral corticosteroids. However, high-dose corticosteroids are poorly tolerated in the elderly and their use has probably contributed to the high mortality rates observed in several cohorts. Accordingly, considerable effort has been directed at identifying corticosteroid-sparing agents, such as immunosuppressant drugs, plasma exchange techniques, intravenous immunoglobulins and tetracycline, that can be used in this clinical setting. Many of these options have appeared to be useful in open series, but they have been found to be ineffective or only marginally effective when tested in randomised, controlled trials. An important breakthrough occurred with the demonstration in a large, randomised trial that a 'super-potent' topical corticosteroid (clobetasol propionate) was not only associated with a significant decrease in severe complications and mortality of BP patients, but was also more effective than oral prednisone. New strategies for BP should include topical clobetasol propionate as first-line therapy in the elderly and consider adjuvant therapy only in the very rare cases that are either resistant or intolerant to this treatment.

Administration, Topical↗

Usefulness of cutaneous T-cell clonality analysis for the diagnosis of cutaneous T-cell lymphoma in patients with erythroderma.

CONTEXT: Demonstration of a dominant T-cell clone in skin biopsy specimens by a molecular assay constitutes an additional diagnostic criterion to differentiate cutaneous T-cell lymphomas (CTCLs) from inflammatory dermatoses. OBJECTIVE: To determine which patients, depending on their clinical presentations, could most benefit from a cutaneous T-cell clonality analysis in addition to histopathologic analysis for the diagnosis of CTCL. DESIGN: Comparison of sensitivity and specificity of histopathologic analysis and a combination of this method and the detection of a T-cell receptor gamma chain gene rearrangement by polymerase chain reaction denaturing gradient gel electrophoresis performed on skin biopsy specimens obtained at initial presentation. PATIENTS: One hundred forty consecutive patients were classified into 4 groups, depending on their clinical presentation: (1) eczematous patches suggestive of early-stage mycosis fungoides (MF) (IA and IB of the TNM classification) (n = 42); (2) plaques, nodules, or tumors that arise on or are associated with plaques suggestive of late-stage MF (IIB and III of the TNM classification) (n = 16); (3) erythroderma (n = 50); and (4) nodules or tumors that arise in normal skin, suggestive of non-MF CTCL (n = 32). RESULTS: When compared with histopathologic examination, the addition of clonality analysis increased the sensitivity of CTCL diagnosis in all groups of patients except those with cutaneous lesions suggestive of late-stage MF, because the diagnosis was made based on histopathologic analysis alone in 100% of these cases. The main increase in sensitivity of CTCL diagnosis was observed in patients with erythroderma: 62% with histopathologic analysis alone to 87% with the combination of both methods (P = .04). Diagnostic specificity of molecular assays decreased from 100% to 76% (P = .01) in patients with patch lesions and from 100% to 70% (P = .04) in patients with nodules that occurred in normal skin due to the detection of a T-cell clone in 6 patients with follicular mucinosis without a histologic pattern of MF and in 5 of 20 cases of T-cell pseudolymphoma (25%), respectively. In contrast, a T-cell clone was not detected in the 34 patients with erythroderma of inflammatory origin. CONCLUSION: Polymerase chain reaction analysis of cutaneous T-cell clonality could be useful for the diagnosis of CTCL in patients who present with erythroderma.

Clone Cells↗

Blastic NK-cell lymphomas (agranular CD4+CD56+ hematodermic neoplasms): a review.

Blastic natural killer (NK) cell lymphoma (also termed CD4+CD56+ hematodermic neoplasm) is a recently described entity, with the first case reported in 1994. It was suggested initially that the disease originates from NK cells. Since 1994, single cases and a few small series have been published. In this review, data from the literature and a series of 30 cases from the French and Dutch study groups on cutaneous lymphomas are discussed. The major clinical, histopathologic, and phenotypic aspects of the disease and diagnostic criteria and data suggesting a plasmacytoid dendritic cell origin for the tumor cells are provided.

Adult↗

Bcl-2 protein expression is the strongest independent prognostic factor of survival in primary cutaneous large B-cell lymphomas.

Bcl-2 protein expression has been associated with poor prognosis in patients with noncutaneous diffuse large B-cell lymphomas. In primary cutaneous large B-cell lymphomas, the location on the leg, the round-cell morphology defined as the predominance of centroblasts and immunoblasts over large centrocytes, and multiple skin lesions were identified as adverse prognostic factors. The prognostic value of bcl-2 protein expression has not been studied in large series of patients. We evaluated 80 primary cutaneous large B-cell lymphomas collected by the French Study Group on Cutaneous Lymphomas. The prognostic value of age, sex, number of lesions, cutaneous extent, location, serum lactate dehydrogenase (LDH) level, B symptoms, morphology, and bcl-2 protein expression was studied. The overall 5-year specific survival rate was 65%. In univariate analysis, advanced age, multiple skin lesions (n = 48), location on the leg (n = 25), round-cell morphology (n = 32), and bcl-2 expression (n = 39) were significantly related to death from lymphoma. In multivariate analysis, bcl-2 expression (P =.0003), multiple skin lesions (P =.004), and age remained independent prognostic factors. The 5-year specific survival rates in bcl-2-positive and bcl-2-negative patients were 41% and 89%, respectively (P <.0001). A new prognostic classification of primary cutaneous B-cell lymphoma should be based primarily on bcl-2 protein expression rather than the location of skin lesions.

Adult↗

[Clear cell dermatofibroma: a case report with cytogenetic study].

We report an observation concerning a 48-year-old male who presented with a 5 cm tumour on his left leg, first noticed 18 months ago. The remainder of clinical examination was normal. Histological assessment revealed a tumoral infiltration of entire dermis and superficial hypodermis. This tumour consisted of monomorphous, ovoid or spindle cells, with clear cytoplasm and PAS+ granulations. There was strong immunoreactivity by tumoral cells only for vimentin. Ultrastructural studies revealed fibrohistiocytic-like tumoral cells, without epithelial, muscular, vascular or melanocytic differentiation. These results were consistent with the diagnosis of clear cell dermatofibroma. Cytogenetic evaluation and FISH analysis showed a deletion of p12. Clear cell dermatofibroma is a rare and recent variant of dermatofibroma, with a difficult histological evaluation and which must be differentiated from clear-cell sarcoma. This observation is the first case-report of this entity, to our knowledge, showing a cytogenetic abnormality.

Chromosomes, Human, Pair 12↗

Complete germline deletion of the STK11 gene in a family with Peutz-Jeghers syndrome.

Peutz-Jeghers syndrome (PJS, MIM175200) is an autosomal-dominant inherited disorder characterised by multiple gastrointestinal hamartomatous polyps, melanin spots of the oral mucosa and digits, and an increased risk for various neoplasms. The PJS results from germline alterations of the STK11/LKB1 tumour suppressor gene, located on 19p13.3, and encoding a serine/threonine kinase. The detection of STK11 germline mutations, in only 50-70% of PJS families, has suggested a genetic heterogeneity of the disease. We report the case of a family with typical features of PJS, including gastrointestinal hamartomatous, breast cancers and melanin spots of the oral mucosa. Quantitative multiplex PCR of short fluorescent fragments (QMPSF) of the 19p13 region allowed us to identify an approximately 250 kb heterozygous deletion removing entirely the STK11 locus. This report, which constitutes the first description of a complete germline deletion of STK11, shows that the presence of such large genomic deletions should be considered in PJS families without detectable point mutations of STK11.

AMP-Activated Protein Kinase Kinases↗

Solid-phase functionalization of peptides by an alpha-hydrazinoacetyl group.

A novel procedure for the preparation of alpha-hydrazinoacetyl peptides is reported on the basis of the solid-phase coupling of partially or fully Boc-protected hydrazino acetic acid derivatives. The degree of unwanted polymerization of the activated ester during both activation and coupling was found to be significant for the monoprotected derivative BocNHNHCH(2)CO(2)H but could be minimized with the diprotected derivative BocNHNH(Boc)CH(2)CO(2)H and suppressed with the fully protected acid. Despite the instability of the imidocarbonate group toward acids and bases, a low-cost and effective route was sought for the preparation of the tris(Boc)-protected derivative. The N,N,N'-tris(Boc)hydrazinoacetic acid could be introduced on the solid phase after or before peptide elongation using Fmoc/tert-butyl chemistry. In this latter case, HR MAS NMR analysis of model solid supports demonstrated the partial loss of one Boc group during the repetitive piperidine treatments. Despite this slight instability, N,N,N'-tris(Boc)hydrazinoacetic acid was found to be a highly convenient reagent for the robust and easily scalable preparation of hydrazinopeptides in good yield and high purity.

Amino Acid Sequence↗