Giardia lamblia causes malabsorption and steatorrhea without invading the intestinal mucosa. The ventral sucking disc attaches to the brush border. Which virulence factor is primarily responsible for this attachment and subsequent microvillus damage?
- A Variant specific surface protein
- B Trophozoite surface antigen 1
- C Giardia lectin ✓
- D Cysteine proteases
Correct answer: C. Giardia lectin
Explanation
Giardia lamblia attaches to the intestinal epithelium via its ventral sucking disc. The attachment is mediated by a mannose-binding lectin on the trophozoite surface that binds to host epithelial cell receptors. This leads to microvillus blunting and malabsorption. Variant specific surface protein is for immune evasion. Cysteine proteases are involved in tissue invasion by Entamoeba.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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