Mount Sinai School of Medicine researchers discovered that cannabis-like chemicals trigger receptors on human immune cells that can directly inhibit a type of human immunodeficiency virus (HIV) found in late-stage AIDS, according to findings published online in March of 2012 in the journal PLoS ONE. Triggering CB1 causes the drug high associated with cannabis, making it undesirable for physicians to prescribe. The researchers wanted to explore therapies that would target CB2 only. The Mount Sinai team infected healthy immune cells with HIV, then treated them with a chemical that triggers CB2 called an agonist. They found that the drug reduced the infection of the remaining cells.