AUTHOR=Rezende-Gondim Mariana M. , da Silva Aristeu V. , Dubey Jitender P. , Schares Gereon R. M. , Gondim Luís F. P. 

TITLE=Immunomagnetic separation of Toxoplasma gondii and Hammondia spp. tissue cysts generated in cell culture

JOURNAL=Frontiers in Veterinary Science

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2022.1033380

DOI=10.3389/fvets.2022.1033380

ISSN=2297-1769

ABSTRACT=<p><italic>Toxoplasma gondii</italic> is commonly transmitted among animals and humans by ingestion of infected animal tissues or by consumption of food and water contaminated with environmentally-resistant oocysts excreted by cats. Tissue cysts and oocysts have different walls, whose structures and compositions are poorly known. Herein, we describe an immunomagnetic separation (IMS) method that was successfully used for purification of <italic>T. gondii</italic> tissue cysts generated in cell culture. We used an IgG monoclonal antibody (mAb) that reacts against antigens in tissue cyst walls. Many <italic>in vitro</italic> produced cysts were obtained by this IMS; &gt;2,000 <italic>T. gondii</italic> cysts were isolated from a single culture flask of 25 cm<sup>2</sup>. Tissue cysts from two <italic>Hammondia</italic> spp., <italic>H. hammondi</italic>, and <italic>H. heydorni</italic>, produced in cell culture were also separated using this method. As a reference, purification of tissue cysts by Percoll gradients was used. Percoll was able to separate <italic>T. gondii</italic> tissue cysts produced in mice but was not suitable for purifying <italic>T. gondii</italic> tissue cysts produced <italic>in vitro</italic>. The IMS described here should favor proteomic studies involving tissue cysts of <italic>T. gondii</italic>.</p>