Immunofluorescence Staining of Host Cell Proteins

Commercial primary antibodies used were: mouse anti-keratin-8 (Sigma-Aldrich, St. Louis, MO, USA), mouse anti-keratin-18 (Sigma-Aldrich), mouse anti-vimentin (Abcam, Cambridge, MA, USA), rabbit anti-SUMO-1 (Abcam), rabbit anti-SUMO-2/3 (Abcam), rabbit anti-Ubc9 (Santa Cruz Biotechnology, Dallas, TX, USA), mouse anti-β-actin (Santa Cruz Biotechnology), and mouse anti-human GAPDH (Sigma-Aldrich). Mouse and rabbit antisera against APH0032 were described previously [33 (link)]. Rabbit antiserum against A. phagocytophilum protein P44 was described previously [34 (link)]. Mouse anti-β-tubulin and Alexa Fluor phalloidin 555 were kind gifts from Jessica Bell (University of San Diego, San Diego, CA, USA) and Lynne Elmore (Virginia Commonwealth University, Richmond, VA, USA), respectively. Secondary antibodies conjugated to Alexa Fluor fluorochromes were obtained from Thermo Fisher Scientific (Waltham, MA, USA).