Indirect immunofluorescence on patient serum is requested to confirm pemphigus vulgaris. Which substrate gives the highest sensitivity for detecting circulating intercellular antibodies?
- A Guinea pig oesophagus
- B Monkey oesophagus ✓
- C Rat urinary bladder
- D Salt-split normal human skin
Correct answer: B. Monkey oesophagus
Explanation
Monkey oesophagus is the standard, most sensitive substrate for pemphigus vulgaris because its stratified squamous epithelium expresses desmoglein 3 abundantly. Guinea pig oesophagus is rich in desmoglein 1 and is preferred for pemphigus foliaceus, making it the tempting distractor. Rat urinary bladder transitional epithelium is the classic substrate for paraneoplastic pemphigus antibodies against envoplakin and periplakin. Salt-split skin is used to localise subepidermal blistering antibodies, not intercellular pemphigus antibodies.
Reference: Bolognia, Dermatology, 5th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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