Dm2500 system

Fluorescence microscopy imaging was carried out on Leica DM2500 system equipped with 100X PL APO objective. FM4-64 (N-(3-Triethylammoniumpropyl)-4-(6-(4-(Diethylam- ino) Phenyl) Hexatrienyl) Pyridinium Dibromide) was obtained from Invitrogen, and was used following the supplier’s instructions. Acetamide-induced culture of M. smegmatis carrying pMA-GFP was counterstained with FM4‐64 membrane staining dye for 30 min, washed thrice with PBST (Phosphate buffered saline with Tween-20), resuspended in 0.1 ml of PBST, and imaged. The imaging was carried out by using GFP (488 nm) and FM4‐64 (506 nm) filters.

The formalin-fixed placenta samples underwent routine histological processing. For immunohistochemical analysis, paraffin sections (5 μm) were stained with primary antibodies to ERα (ab3575, 1:100, Abcam), CD68 (ab125212, 1:100, Abcam), CD206 (ab64693, 1:100, Abcam) manually. The immunoperoxidase-stained sections were counterstained with Mayer’s hematoxylin. Paraffin sections were stained with primary to CD56 (NCL-CD56-504, clone CD564, Leica Biosystems, Wetzlar, Germany) in a Leica BOND-MAX Automated Immunostainer with further incubation with immunoperoxidase-conjugated antibodies and counterstaining with hematoxylin included in the CD56 staining kit. For each section, 10 images were obtained on a Leica DM2500 system.