Which complement pathway is activated by mannose-binding lectin (MBL) recognizing carbohydrate patterns on microbial surfaces?

• A Classical pathway
• B Lectin pathway ✓
• C Alternative pathway
• D Terminal common pathway only

Explanation

The lectin pathway is activated when mannose-binding lectin (MBL) or ficolins bind mannose-rich carbohydrates on microbial surfaces. MBL then associates with MASP-1 and MASP-2 (MBL-associated serine proteases), which cleave C4 and C2 in a manner analogous to C1 in the classical pathway. The alternative pathway is activated spontaneously on microbial surfaces by C3 hydrolysis; the classical pathway requires C1q-antibody complexes.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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