Description
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.