Wan Bing seldom leaves Jiachuan, a town in mountainous Wangcang county, Sichuan province, where he is a grassroots public servant in charge of enterprise management in town government.

But on Wednesday, Wan took a two-hour flight from Guangyuan, the city that administers Wangcang, to Beijing to "help save the life of a US citizen in the Western hemisphere," he said in a telephone interview.

Wan, 43, will stay in Beijing for five days before he donates hematopoietic stem cells to a 61-year-old US woman who has leukemia.

According to the Sichuan chapter of the Red Cross Society of China, Wan will be the first in the province to donate hematopoietic stem cells to a foreigner. His human leukocyte antigens, molecules that play a key role in immune response, match those of the woman, which means their tissue types are compatible.

"It is good to save somebody's life, whether she is a foreigner or Chinese," Wan said.

He said he will be injected with a mobilization agent each day so that the hematopoietic stem cells in his bone marrow will be transferred to his blood, which he'll then donate.

The donation will then be flown to the United States.

Fu Qiang, 45, a longtime blood donor from Ma'anshan, Anhui province, said it is rare for a person's human leukocyte antigens to match those of an unrelated person. "It is even more rare for one's HLA to match a foreigner's," Fu said. "The odds are like one in a million."

Wan said he was surprised to learn his HLA matched a foreigner's when the Wangcang County Red Cross asked him whether he was willing to donate the stem cells.

A graduate of a college in Mianyang, Sichuan, where he majored in agriculture, Wan has worked in his home county of Wangcang as a public servant.

"He is a warm-hearted person and is always ready to help the needy," said Zou Jian, a young colleague in the town government who underwent surgery for a brain tumor two years ago. "When I was sick, he donated money to me even though his wife had been laid off and they were not rich."

Since 2010, Wan has donated blood to the county blood center once a year. He was inspired by a news report in 2007 about a 6-year-old boy who had leukemia.

"On TV, I saw his face covered with a mask and he had no hair. As my daughter Wan Zhao was only six years older, I was filled with sympathy for him and wanted to donate hematopoietic stem cells," Wan said.

While donating blood in April 2012, he left a sample of his hematopoietic stem cells at the county blood center. That sample was a match with the woman from the United States.

To prepare for his donation, Wan stayed away from spicy food and liquor during Spring Festival.

"As natives of Sichuan, we like spicy food. But we spent the festival without any," said his wife, Chen Cuilan.

China has 1 million leukemia patients, and 40,000 more people are diagnosed with the disease each year. Only 4,000 people have donated hematopoietic stem cells, Fu said.