more detail by way of examples although it goes without saying that the present invention is not limited to the embodiments mentioned in those examples only incidentally in the following examples each operation was carried out according to the method mentioned in molecular cloning by sambrook j fritsh e f and maniatis t published by cold spring harbor press in 1989 unless otherwise mentioned or when a commercially available reagent or kit was used it was used according to the directions for use thereof isolation of cdna of human cell membrane surface molecule 4f2hc and preparation of crna 1 preparation of cdna fragment coding for rat 4f2hc by means of an rt pcr according to the conventional method pure poly a rna was prepared from liver of rat 5 u2032 primer seq id no 9 and 3 u2032 primer seq id no 10 were also synthesized based upon a cdna sequence biochem j vol 312 p 863 1995 coding for rat 4f2hc an rt pcr reverse transcription polymerase chain reaction jikken igaku supplementary issue u201c pcr and its applications u201d vol 8 no 9 1990 and u201c gene amplification pcr u2014 its basis and new developments u201d published by kyoritsu.