Characterization of protein profile and evaluation of immune-peptide of crude and Excretory/Secretory antigens of some haematophagus leeches of India

Leech infestation leads to significant blood loss compared to other parasites, causes irritation in humans and predisposes livestock to secondary fly attack and maggot infestation. During blood feeding, leeches inject saliva containing bioactive proteins at the bite site that facilitate continuous blood flow and provoke inflammatory responses. The present study was undertaken to characterize the crude and excretory/secretory (E/S) antigens of three common leech species of Northeast India- two aquatic (Hirudinaria manillensis and H. granulosa) and one terrestrial (Haemadipsa sylvestris). Protein quantification revealed higher concentrations of crude antigens (3.60–4.14 g/dL) compared to E/S antigens (3.39–3.44 g/dl). Electrophoretic analysis showed 9 peptide bands in crude antigens (12.5-96 kDa) and five bands in E/S antigens (14-96 kDa), with no major differences in overall banding patterns. Periodic acid–Schiff (PAS) staining revealed the presence of two glycoproteins in the crude extracts of H. manillensis and H. granulosa and three in H. sylvestris (12.5–26 kDa). Glycoproteins could not be detected in E/S products of any of the three species. Hyperimmune serum raised in rabbits against both crude and E/S antigen was used for Enzyme immunotransfer blot (EITB) analysis, which detected two immune-reactive peptides in the crude antigens of H. manillensis and H. granulosa, and one in the E/S product of H. sylvestris.