"More and more research is identifying potential beneficial effects of substances contained in marijuana, but a major challenge has been identifying the molecular pathways involved," said John Wherry, Ph.D., deputy editor of the Leukocyte Biology. "These new studies point to important roles for the cannabinoid receptors as targets that might be exploited using approaches that refine how we think about substances derived from marijuana."

Some states are starting to catch up with the science around marijuana and organ transplants. California this year approved Assembly Bill 258, which prohibits discrimination against medical marijuana patients in the organ transplant process. That is good news, but it came only after the unnecessary deaths of people like Norman Smith.

Smith, 64, legally used medical marijuana as part of his treatment for liver cancer, but was removed from the waiting list by Cedars-Sinai Medical Center in Los Angeles after testing positive for marijuana in a drug test. Under program rules, he had to test negative for marijuana for six months before he could get back on the list, but he died before that happened.

California has taken steps to redress this iniquity, but medical marijuana patients in other states still face transplant denial and early death. It would be a cruel irony indeed if they are denied organ transplants because they use the very substance that could help avoid rejecting them.