AUTHOR=Nakashima Fabiana , Pardo Valquíria Sousa , Miola Marcos Paulo , Murata Fernando Henrique Antunes , Paduan Natalia , Longo Stefani Miqueline , Brandão de Mattos Cinara Cássia , Pereira-Chioccola Vera Lucia , Ricci Octávio , de Mattos Luiz Carlos 

TITLE=Serum IgG Anti-Toxoplasma gondii Antibody Concentrations Do Not Correlate Nested PCR Results in Blood Donors

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=9

YEAR=2020

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2019.00461

DOI=10.3389/fcimb.2019.00461

ISSN=2235-2988

ABSTRACT=<p><bold>Background:</bold><italic>Toxoplasma gondii</italic> infects millions of individuals worldwide. This protozoan is food and water-borne transmitted but blood transfusion and organ transplantation constitute alternative forms for transmission. However, the influence of IgG anti-<italic>T. gondii</italic> antibodies in molecular analysis carried out in peripheral blood still remain unclear. This study aimed to investigate the serum IgG anti-<italic>T. gondii</italic> antibody concentrations correlate Nested PCR results in blood donors.</p><p><bold>Methods:</bold> 750 blood donors were enrolled. IgM and IgG anti-<italic>T. gondii</italic> antibodies were assessed by ELISA (DiaSorin, Italy). Nested PCR was performed with primers JW62/JW63 (288 bp) and B22/B23 (115 bp) of the <italic>T. gondii B1</italic> gene. The mean values of IgG concentration were compared for PCR positive and PCR Negative blood donors using the <italic>t</italic>-test or Mann-Whitney according to the normal distribution (<italic>p</italic>-value ≤ 0.05).</p><p><bold>Results:</bold> 361 (48.1%) blood donors presented positive serology as follow: IgM<sup>+</sup>/IgG<sup>−</sup>: 5 (0.6%); IgM<sup>+</sup>/IgG<sup>+</sup>: 21 (2.8%); IgM<sup>−</sup>/IgG<sup>+</sup>: 335 (44.7%) and 389 (51.9%), negative serology. From 353 blood donors with positive serology tested, the Nested PCR was positive in 38 (10.8%) and negative in 315 (89.2%). There were no differences statistically significant between the mean values of serum IgG anti-<italic>T. gondii</italic> antibody concentrations and the Nested PCR results.</p><p><bold>Conclusions:</bold> In conclusion, our data show that variations in the serum IgG anti-<italic>T. gondii</italic> antibody concentrations do not correlate <italic>T. gondii</italic> parasitemia detected by Nested PCR in chronically infected healthy blood donors.</p>