Reticular fibres form the delicate supporting stroma of lymph nodes, spleen, bone marrow and liver sinusoids. Which statement identifies them correctly?

• A They are type I collagen fibres that stain bright pink with H and E
• B They are elastin-rich fibres stained black by Verhoeff van Gieson
• C They are type IV collagen networks forming the lamina densa of basement membranes
• D They are type III collagen fibres, argyrophilic with silver impregnation and invisible on routine H and E ✓

Explanation

Reticular fibres consist of type III collagen coated with proteoglycans and glycoproteins. They are argyrophilic, meaning they reduce silver salts and appear black with silver impregnation, yet are too thin and too hydrated to be distinguished on routine H and E, which is why special stains are required. Type IV collagen, option C, forms the sheet-like network of basement membranes, not individual branching fibres. Elastin fibres are a separate fibre class stained by orcein or Verhoeff van Gieson.

Reference: Junqueira's Basic Histology, 16th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.