Department;
of;
Pathogenic;
Biology;
and;
Immunology,;
Southeast;
University;
School;
of;
Basic;
Medical;
Science,;
Nanjing;
210009,;
China;
Department;
of;
Pathology;
and;
Laboratory;
Medicine,;
Emory;
University;
School;
of;
Medicine,;
Atlanta,;
Georgia;
30222,;
USA;
Department;
of;
Obstetrics;
and;
Gynecology,;
affiliated;
Zhongda;
Hospital,;
Southeastern;
University,;
Nanjing;
210009,;
China;
Department;
of;
Microbiology;
and;
Molecular;
Genetics,;
Harvard;
Medical;
School,;
Boston,;
MA02115,;
USA;