Sheep perforin: identification and expression by γδ T cells from pregnant sheep uterine epithelium

γδTCR-positive intraepithelial lymphocytes (IEL) in sheep uterus have been shown in previous studies to express CD8 and to contain prominent intracytoplasmic granules, indicating that they may be cytotoxic. Sheep perforin, which has not previously been described, was identified in the present study using RT-PCR based on primers from human and mouse perforin sequences. A 290 base pair (bp), partial sheep perforin sequence was obtained which showed 80.3% and 66.2% nucleotide identity with human and mouse perforin, respectively. γδTCR+ IEL from sheep pregnant uteri were found to express perforin mRNA providing further evidence that these cells are cytotoxic.