An update on medium- and low-abundant blood plasma proteome of horse.

This research attempts to analyze horse serum proteins and improve their concentration through high-abundant protein depletion, using advanced electrophoresis and spectrometry techniques. The results of the study promises to be useful for future investigations into changes in horse plasma proteins in various physiological conditions.

Study Objectives and Methodology

In this study, the investigators analyzed the serum protein composition in a species of horse (Equus caballus). They aimed to:

• Deeply analyse the serum protein composition of Equus caballus
• Assess the effectiveness of the method used to reduce high-abundant proteins
• Enhance the concentration of medium- and low-abundant proteins for better investigation.

The experiment was carried out using the blood plasma from three healthy part-Arabian mares. Advanced techniques such as two-dimensional electrophoresis and matrix-assisted laser desorption/ionisation – time of flight mass spectrometry were utilized to map the horse plasma proteome (the entire set of proteins that can be expressed by the horse genome).

Findings and Implications

The researchers resolved serum proteins at pH 4 to 7, followed by a 12% SDS-PAGE, a technique used for protein separation. This led to the identification of 136 spots, which represent 46 unique gene products. Notably, 22 of these gene products were identified for the first time in horse serum/plasma samples using proteomic tools — tools used to study the structure and function of proteins.

Furthermore, gene ontology analysis revealed that nearly 30% of all identified gene products belong to the coagulation and complement cascades, important processes in blood clotting and immune response. These findings indicate the potential use of the horse plasma proteome as a precursor for future analyses of changes in horse plasma proteome in different physiological and pathophysiological conditions.

Significance of the Study

The study especially highlighted the usefulness of the medium- and low-abundant protein enrichment tool. By depleting the most abundant plasma proteins, namely albumin, IgG heavy chains, and serotransferrin, the tool enabled the identification of a higher number of protein gene products. This approach essentially increases the richness and depth of protein identification for future research, offering a more comprehensive view of the horse plasma proteome. This, in turn, could potentially lead to a better understanding of physiological and pathological changes in equine health and diseases.