China breeds first transgenic cow with cancer-fighting proteins for humans

New Delhi, Aug 11 : Researchers in China have bred a genetically altered cow that can produce cancer-fighting proteins for humans.

The cow, capable of producing CD20 antibodies in its milk, was born in Beijing on Aug. 2 and a dozen more are due to be born next month.

According to researchers, mass breeding of the animal would enable China to mass-produce the therapeutic proteins cheaply, reports Xinhua.

Lead author Li Ning, an academician with China Academy of Engineering, said that the human monoclonal (produced from a single cell) antibodies could be purified from the milk of the transgenic cow, and used to treat B cell lymphomas and leukemias and some auto-immune diseases.

"After 10 days of careful observation, we are happy to see the cow is very healthy," Li, whose laboratory is based in the China Agriculture University, said.

The weight of the calf at birth was 38 kg and in seven to eight months, the researchers would induce lactation to test its antibody expression.

The development is expected to significantly reduce the costs ofCD20 antibody production, which currently uses chimeric anti-CD20 CHO (Chinese hamster ovary) cells.

The low antibody expression level and high cost of cell culture has been a stumbling block in the industrial production of the antibody drug, which was approved by the U.S. Food and Drug Administration in 1997.

CD20 cell-surface proteins found in mature B cells become cancerous in patients who suffer from non-Hodgkins lymphoma, which accounts for about 40 percent of all new cases of lymphoma. It is identified as the target in the treatment of lymphomas.

"The objective of our research is to make the transgenic animal express the antibody at high levels," said Li.

Li added that transgenic mice had been able to express 10 mg/ml of CD20 antibody on average in tests.

The U.S.-based Business Communication Corp. has estimated the worldwide market for transgenically sourced therapies at more than1 billion U.S. dollars in 2008, and 18.6 billion dollars by 2013.

Researchers planned to complete the clinical study of the first functional food with the antibody in three years, and apply for production authorization from China's food and drug authorities, and the first functional drug could be expected in five years.

ANI