Separation and purification of Toxoplasma gondii tachyzoites from in vitro and in vivo culture systems.

In this study, we evaluated four methods to separate and purify Toxoplasma gondii tachyzoites from in vivo and in vitro culture systems, including trypsin digestion, purification with a 3-µm filter, CF-11 cellulose purification, and Percoll purification. Our results indicate that both purification with a 3-µm filter and CF11 cellulose purification methods remove leukocytes or HeLa cells, and can therefore be used as candidate methods for the purification of in vivo and in vitro culture products. Trypsin digestion had a high tachyzoite recovery rate, but 22.35% of leukocytes and 69.64% of HeLa cells remained in the purified products. Percoll solution [30% (v/v)] also had a high tachyzoite recovery rate, but 3.44% of leukocytes and 61.61% of HeLa cells remained in the purified products. The 40% Percoll solution was also a candidate method for purifying tachyzoites from in vivo culture products, with a 65.45% tachyzoite recovery rate and without leukocytes.