Immunophenotyping of Sheep Paraffin-Embedded Peripheral Lymph Nodes

Area of Science:

• Veterinary Immunology
• Comparative Immunology
• Mammalian Immune System Architecture

Background:

• Sheep are vital livestock and important large animal models in biomedical research.
• Understanding the sheep immune system contributes to broader knowledge of mammalian immunology.
• Lymph nodes are critical sites for orchestrating adaptive immune responses.

Purpose of the Study:

• To comprehensively immunophenotype key cell populations within sheep lymph nodes.
• To identify potential subpopulations of antigen-presenting cells and stromal cells.
• To provide tools for investigating sheep immune system structure, activation, and regulation.

Main Methods:

• Application of immunohistochemistry and multicolor immunofluorescence on fixed, paraffin-embedded lymph nodes.
• Utilized an extensive antibody panel targeting dendritic cells, macrophages, stromal cells, and lymphocytes.
• Explored various tissue fixation and antigen retrieval methods for detailed analysis.

Main Results:

• Detailed immunophenotyping of sheep lymph node cell populations, including antigen-presenting cells, lymphocytes, and stromal cells.
• Identification of specific markers (e.g., MHC class II, CD83, CD208, CD11b, CD163, CD169, CNA.42, S100, CD3, Pax5, CD4, CD8) for cell characterization.
• Characterization of cell combinations, morphology, and location within lymph node architecture.

Conclusions:

• Established a detailed immunophenotype of sheep lymph nodes, enhancing their utility as a research model.
• Provided new tools and insights for studying the sheep immune system in health and disease.
• Facilitated further investigation into the structure, activation, and regulation of adaptive immunity in sheep.