Macrophages were cultured in complete media containing DMEM, 10% (v/v) heat inactive FBS, 20% (v/v) L929 preconditioned medium, 2.5% (v/v) HEPES, 2 mM Lglutamine, 100 U/ml penicillin and 100 µg/ml streptomycin, 2% sterile-filtered β-mercaptoethanol, 1X non-essential amino acids and 1 mM sodium pyruvate. Bone marrow isolation and macrophage differentiation was modified from 81 , employing L929 preconditioned medium as the source of M-CSF for differentiation. Briefly, scissors and forceps were used to dissect femurs and tibiae from adult mice, and muscle tissue was carefully removed from bones. Clean femurs and tibiae were placed in a tissue culture dish containing complete media. The ends of each bone were cut with scissors to expose bone marrow. Bone marrow was flushed with a 25-gauge needle attached to a 10 ml syringe containing complete media. Media containing bone marrow was passed through a 70 µm cell strainer and precursor cells were plated on non-tissue culture treated 10 cm bacteriological plates containing 10 ml complete media. This was marked as day 0 of isolation. On day three postisolation, macrophages were topped up with 5 ml fresh complete media. On day seven post-isolation, macrophages were rinsed once with PBS and incubated with versene for 5 minutes in a 37°C 5% CO2 tissue culture incubator. Macrophages were detached with cell scrapers and were centrifuged at 1200 rpm for 5 minutes at room temperature. The versene was aspirated and the remaining cell pellet was resuspended in complete media. The cell suspension was counted, and cells were seeded for experimental analysis in a 6-well format, in tissue culture treated dishes at a final cell density of one million cells per well of a 6-well plate.