1 Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA, 17033, USA. cwang6@pennstatehealth.psu.edu.
2 Department of Molecular and Cellular Biochemistry, 212 S. Hawthorne Dr, Bloomington, IN, 47405, USA. linchen@indiana.edu.