Which lipid stain is listed as a staining option for lipoprotein visualization?

Which lipid stain is listed as a staining option for lipoprotein visualization?

• A. Congo red
• B. Oil Red O
• C. Hematoxylin
• D. Toluidine blue

Answer: (B)

The main idea is using a dye that specifically binds and highlights lipids. Oil Red O is designed to stain neutral lipids—triglycerides and cholesterol esters—found in lipoprotein particles, giving them a vivid red color. Because lipids can be removed during standard paraffin processing, this stain is typically applied to frozen (cryosection) tissue so the lipids remain intact and visible. Often a counterstain like hematoxylin is used to provide contrast, highlighting cell nuclei in blue. Congo red is used for amyloid, producing apple-green birefringence under polarized light. Hematoxylin stains nuclei and many basophilic structures, not specifically lipids. Toluidine blue highlights acidic tissue components and can stain mast cell granules, but it’s not a lipid-specific stain.

The main idea is using a dye that specifically binds and highlights lipids. Oil Red O is designed to stain neutral lipids—triglycerides and cholesterol esters—found in lipoprotein particles, giving them a vivid red color. Because lipids can be removed during standard paraffin processing, this stain is typically applied to frozen (cryosection) tissue so the lipids remain intact and visible. Often a counterstain like hematoxylin is used to provide contrast, highlighting cell nuclei in blue.

Congo red is used for amyloid, producing apple-green birefringence under polarized light. Hematoxylin stains nuclei and many basophilic structures, not specifically lipids. Toluidine blue highlights acidic tissue components and can stain mast cell granules, but it’s not a lipid-specific stain.