This report from ABC News discusses the use of fetal lung tissue in vaccines:
http://abcnews.go.com/Health/aborted-fetuses-vaccines/story?id=29005539
Questions have been raised about whether vaccines are made using fetal tissue. The answer is more nuanced than many people realize.
Some vaccines have been developed or manufactured using human cell lines (such as WI-38 and MRC-5) that originated from tissue obtained from two elective abortions performed in the 1960s. Those original cells have been reproduced in laboratories for decades. No ongoing abortions are required to maintain these cell lines.
These cell lines have been used because certain viruses grow well in human cells, making vaccine production more effective. During manufacturing, the viruses are grown in the cells and then purified. The finished vaccines do not contain fetal tissue, although trace amounts of residual cellular DNA may remain after purification.
The use of these historic cell lines has generated ethical debate. Some religious organizations have concluded that receiving these vaccines can be morally acceptable when no comparable alternative exists while also encouraging the development of vaccines that do not rely on these cell lines.
