In 2006, Dr. Dale Umetsu, Dr. Omid Akbari and colleagues reported that a newly recognized type of immune cell, NKT, may play an important role in causing asthma, even in the absence of conventional T-helper cells. In addition, NKT cells respond to a different class of antigens that are currently recognized to trigger asthma. In that same year, Dr. Larry Benowitz and colleagues discovered a naturally occurring growth factor called oncomodulin that stimulates regeneration in injured optic nerves, raising the possibility of treating blindness due to optic-nerve damage and the hope of achieving similar regeneration in the spinal cord and brain.