By acquiring peripheral blood lymphocyte antibody gene libraries from 25 healthy people around the world (including Chinese, Japanese, Filipinos, Vietnamese, Cambodians, Latin Americans, Caucasians, African-Americans, American Indians, Germans, Canadians, French, British, Russians, Mongolians, etc.) The heavy chain variable region gene, using genetic engineering and phage display technology, has constructed a total of 20 billion clones of single-chain antibody phage library.