Macrophages from sex-reversed chicken embryos [set1]

To identify markers associated with inherent cellular sex-identity, we analysed cultured macrophages from male and female chick embryos. We found that male and female macrophages respond differently to stimulation by bacterial lipopolysaccharide and that female macrophages constitutively express higher levels of interferon target genes than male macrophages. To determine whether these differences resulted from the actions of gonadal hormones, we induced gonadal sex-reversal to alter the hormonal environment of the developing chick and analysed different tissues and macrophages from male and female embryos. Macrophages were collected from leg-bones of chicken embryos at day 13 of development after administration of either 1mg fadrozole, or 100ul PBS as control, at day 3 of development. Two pools of macrophage cultures were made for each of the following: male control, male fadrozole-treated, female control, female fadrozole-treated. Cells were cultured in either standard medium or in medium containing lipopolysaccharide (LPS) to activate the macrophages. Macrophages were harvested and RNA collected for microarray analysis.