Characterization of Immune System Cell Subsets in Fixed Tissues from Alpine Chamois (Rupicapra rupicapra)

Area of Science:

• Veterinary immunology
• Wildlife health
• Immunohistochemistry

Background:

• Understanding immune cell populations is crucial for wildlife health.
• Alpine chamois (Rupicapra rupicapra subspecies rupicapra) immune systems are not well-characterized.
• Lymph nodes and spleen are key immune organs.

Purpose of the Study:

• To immunohistochemically characterize immune cell subsets in alpine chamois.
• To evaluate different tissue fixation methods for immune cell identification.
• To establish a basis for future studies on chamois immune responses and diseases.

Main Methods:

• Immunohistochemistry was performed on lymph node and spleen tissues from alpine chamois.
• Seven primary antibodies targeting immune cell markers (CD3, CD79αcy, CD68, CD4, CD8, CD21, γδ T-cell receptor) were tested.
• Tissues were fixed using formalin or zinc salts (ZS) for comparison.

Main Results:

• Cross-reactivity of antibodies with chamois immune cell epitopes was confirmed.
• Zinc salt fixation enabled broader immune cell identification without antigen retrieval.
• CD4(+) and CD21(+) cells were exclusively identified in ZS-fixed tissues.
• Human CD3, CD79, and CD68 antibodies successfully detected chamois immune cells in both fixation types.
• Immune cell distribution and reactivity were comparable to other ruminants.

Conclusions:

• This study provides a validated immunohistochemical method for studying chamois immune cells.
• ZS fixation is a superior method for identifying specific immune cell subsets in chamois.
• These findings facilitate future research into chamois immunology and disease pathogenesis.