HES - Hematoxylin Eosin Safran
Hematoxylin, Eosin and Saffron (HES) is a trichrome histological stain that expands upon the classical HE stain by introducing saffron as a collagen-specific counterstain. The combination provides enhanced contrast between cellular and extracellular tissue components, making it particularly useful for evaluating connective tissue architecture and fibrosis.
As in HE staining, hematoxylin stains nuclei blue to purple through its affinity for nucleic acids, while eosin stains cytoplasmic proteins, muscle fibers, and erythrocytes in varying shades of pink. The addition of saffron selectively stains collagen and other dense connective tissue structures yellow to orange due to its strong affinity for high-molecular-weight extracellular matrix proteins. This differential staining enables clear discrimination between parenchymal tissue, muscle, and collagen-rich stroma within a single section. HES is therefore particularly valuable in the assessment of fibrosis, wound healing, tissue remodeling, and the histopathological evaluation of organs with abundant connective tissue components.
Typical staining characteristics:
- Nuclei: Blue to purple (hematoxylin)
- Cytoplasm: Pink to red (eosin)
- Muscle fibers: Pink to red (eosin)
- Collagen and connective tissue: Yellow to orange (saffron)
- Erythrocytes: Bright red to orange-red
The enhanced contrast between collagen and surrounding tissue makes HES particularly suitable for studies of fibrosis, scar formation, liver pathology, skin lesions, and tissue repair processes.
Kidney tissue stained with HES. The collagen-rich renal capsule is highlighted in yellow by saffron, clearly distinguishing it from the underlying kidney tissue. Nuclei appear blue-purple, while cytoplasm is stained pink. This strong contrast between connective tissue and parenchyma demonstrates the value of HES staining for visualizing extracellular matrix structures and assessing fibrosis or tissue remodeling.
Heart tissue stained with HES (Atlantic salmon). Cardiac muscle fibers are stained pink by eosin, while collagen-rich extracellular matrix and connective tissue are highlighted in yellow by saffron.