Isolation and characterization of equine nasal mucosal CD172a + cells.

The research investigates and offers a detailed exploration of CD172a(+) cells, a type of antigen-presenting cells (APCs), which are found in the nasal mucosa of horses. The nature and functionality of these cells are further compared against blood-derived monocytes and dendritic cells (DCs).

Research Methodology

• The researchers intensely focused on the antigen-presenting cells (APCs) such as macrophages and dendritic cells, found in the nasal mucosa. They identified these cells to play a vital role in generating primary immune responses and the establishment of immunological memory.
• They isolated CD172a(+) cells from the collagenase-treated equine nasal mucosa fragments using the magnetic-activated cell sorting (MACS) process.
• They used flow cytometry to ascertain the expression of surface markers. Flow cytometry is a common technique that allows researchers to measure physical and chemical characteristics of a population of cells or particles.
• The functionality of the cells was then determined by measuring the uptake of FITC–OVA (Ovalbumin conjugated with a Fluorescein isothiocyanate). This measurement provides an understanding of the cell’s capacity to absorb and process antigens.

Research Findings

• The study found that the cell surface phenotype of the isolated cells were 90% CD172a(+), 30% CD1c(+), 46% CD83(+), 42% CD206(+) and 28% MHC II(+).
• This phenotype variation was different from that of blood-derived monocytes, which was 96% CD172a(+), 4% CD1c(+), 11% CD83(+), 9% CD206(+), 72% MHC II(+).
• The phenotype of blood monocyte derived DCs was 99% CD172a(+), 13% CD1c(+), 30% CD83(+), 51% CD206(+) and 93% MHC II(+).
• The CD172a(+) nasal mucosal cells were functionally capable of endocytosing FITC-OVA, but to a lesser degree than monocyte-derived DCs. Endocytosis is a process where the cells absorb materials from outside their cell membrane.

Conclusion

• The findings suggest that the characterized CD172a(+) nasal mucosal cells can effectively function as antigen presenting cells (APCs), thus they hold pivotal roles in immune responses.
• Importantly, these findings denote that the CD172a(+) nasal mucosal cells closely resemble immature dendritic cells in the nasal area. This knowledge improves our understanding of mucosal immunity, particularly in equines.