Production and characterisation of two monoclonal antibodies recognising equine IgG Fc receptors.

The research in this article focuses on the creation and analysis of two antibodies that recognize IgG Fc receptors in horses. These receptors are crucial for the functioning of the immune system but have not been thoroughly studied in horses.

IgG Fc Receptors and Their Significance

• IgG Fc receptors are an integral part of various immunological mechanisms. They play a prominent role in the immune response of mammals, enabling cells to communicate with each other and recognise foreign invaders.
• Understanding these receptors in domestic animals such as horses is significant as it could potentially lead to advancements in veterinary medicine and immunology in general.

Production of Monoclonal Antibodies

• The researchers produced two monoclonal antibodies – CVS 59 and CVS 61 – that specifically recognize equine IgG Fc receptors. Monoclonal antibodies are identical immune cells that are clones of a unique parent cell, providing the possibility of targeted therapeutic strategies.
• To generate these antibodies, the team used BALB/c mice that were hyperimmunised with equine peripheral blood mononuclear cells. This type of immunisation stimulates an intense immune response, facilitating the production of specific antibodies.
• Hybridoma supernatants, the growth medium where hybridoma cells develop, were screened based on their capacity to inhibit the rosetting (clumping) of equine antibody-coated sheep erythrocytes with equine peripheral blood mononuclear cells. This screening process was important to ensure the produced antibodies’ effectiveness.

Antigen Characterisation and Identification

• The monoclonal antibodies’ antigen distribution was characterised using flow cytometry, a technique used to measure the physical and chemical characteristics of a cell population.
• Immunoprecipitation showed that CVS 59 and CVS 61 could precipitate an 80 and 40 kD protein, respectively, under both reducing and non-reducing conditions. Immunoprecipitation is a method used to isolate a particular protein from a complex mixture using an antibody that can specifically bind to it.
• Based on the functional study, cellular distribution, and molecular weight of the antigen, researchers concluded that the two monoclonal antibodies recognize an epitope on the horse equivalent of human and murine FcgammaRIII and FcgammaRII. An epitope is the specific piece of the antigen to which an antibody binds.