PBMC RNA was isolated with an RNeasy kit (Qiagen, Germany) and messenger RNA was transcribed into cDNA with Reactin Ready First Strand kit (Biomol) and analysed for IL-1RA and GAPDH transcripts by PCR with a HotStart "sweet" PCR mastermix (Biomol) (95°C, 30 sec, 55°C, 30 sec, 72°C, 30 sec, 25 cycles for IL-1RA and 94°C for 30 sec, 50°C for 30 sec and 72°C for 45 sec, 25 cycles for GAPDH) following 18 h incubation with GP.