Biomedical subjects

M Mignogna

Publications and source records attributed to M Mignogna.

4 recordsLinked to original sources

PubMed2006

Comparison of reactivity and epitope recognition between sera from American and Italian patients with oral pemphigoid.

Mucous membrane pemphigoid (MMP) (also known as cicatricial pemphigoid) is a rare autoimmune mucocutaneous blistering disease that affects mucous membranes derived from stratified squamous epithelium and the skin. A subset of MMP affects only the oral cavity and is referred to as the oral pemphigoid (OP). MMP and OP are characterized by subepithelial vesicles on histology and in vivo deposition of immunoglobulins and complement at the basement membrane zone (BMZ) on immunopathology. Previous studies have shown that sera of patients with MMP bind to human integrin beta4, while sera of patients with oral pemphigoid bind to the integrin alpha6 component of the heterodimer. The prognosis in MMP is grave but excellent in OP. In this study we compare the binding of sera from patients with OP from Boston, MA, USA to Naples, Italy, and attempt to identify an epitope to which the anti-integrin alpha6 human autoantibody binds. Our results indicate that the sera from Boston and Naples are identical in their reactivity. They recognize a fragment I (AA 23-462) and its subfragment IB (AA 217-462) only, in the human integrin alpha6 molecule. Blocking studies, immunoprecipitation and immunoabsorbtion studies confirm the presence of this single 245 AA region. Antibodies to subfragment IB cause BMZ separation in organ culture using normal human oral mucosa as substrate. This preliminary study indicates that patients on both continents may have similar reactivity and suggests that an intercontinental study group could be established to advance our understanding of the pathogenesis of OP and the biology of anti-alpha6 integrin autoantibodies.

Animals↗

PubMed2005

Epithelial biology.

The oral mucous membrane has features similar to skin but also differs in several ways. This paper reviews the aspects of epithelial biology necessary for an understanding of the vesiculoerosive disorders.

Animals↗

PubMed2004

The role of upper endoscopy in identifying oesophageal involvement in patients with oral pemphigus vulgaris.

BACKGROUND AND AIMS: The involvement of oesophagus in pemphigus vulgaris is still debated. The aims of this study were to evaluate the prevalence of oesophageal involvement and the gastro-duodenal mucosa appearance before and after high-dose corticosteroid therapy in a group of patients with oral pemphigus vulgaris. METHODS: We prospectively studied 28 consecutive patients with oral pemphigus by oesophageal symptom standardised questionnaire, upper gastro-intestinal endoscopy, exfoliative cytology and histological biopsy. After clinical remission, all patients underwent new endoscopy. RESULTS: The prevalence of oesophageal symptoms was 57.1%. Endoscopic examination revealed oesophageal involvement with different degrees of severity in 67.8% of patients. After corticosteroid therapy, endoscopy showed normal oesophageal-gastro-duodenal mucosa. No examination-related exacerbations of the oesophageal lesions were seen. CONCLUSIONS: The upper gastro-intestinal endoscopic examination, in oral pemphigus vulgaris patients with oesophageal symptoms, is safe in skilled hands technique and a useful diagnostic tool prior to starting therapy.

Drug Therapy, Combination↗

PubMed1998

Novel mutation of the PTEN gene in an Italian Cowden's disease kindred.

Cowden disease (CD) is an autosomal dominant multiple hamartoma syndrome with an elevated risk of thyroid and breast cancers. The CD susceptibility gene has recently been identified as the PTEN/MMAC1/TEP1 gene localized at 10q23 and coding for a dual specificity protein phosphatase. We report the mutational analysis of the PTEN gene in one Italian CD kindred. By using the single strand conformation polymorphism technique and subsequent direct DNA sequencing of the polymerase chain reaction product, we identified a novel mutation in the exon 5 of the PTEN gene. A heterozygous germline TGT-TAT transition was detected at the nucleotide 407; this causes the amino acid substitution cys136-tyr136 and the generation of a new NSI I restriction site. This mutation was not detected in the unaffected member of the family thereby indicating that it is causally linked to the disease. We ruled out that this mutation is a polymorphic variant because it was not detected in over 100 chromosomes analyzed. Using reverse trancriptase-polymerase chain reaction, we detected the expression of the mutant allele in lymphocytes and pathological tissues from an affected member of the family.

Adolescent↗