IgG2 Deficiency May Underlie Cases of Life-threatening Swine Flu

from the Canadian Press:

Researchers from Melbourne, Australia tested pregnant patients with life-threatening swine flu infections for levels of antibody in different antibody subclasses.  This test is rarely done, but is used to investigate possible immune deficiencies.  Serendipitously, the researchers and treating physicians found that one class of antibody (IgG2) was low in most of the patients.  When they gave a mixture of IgGs to critically ill patients, 3 out of 4 who were expected to die, survived.

Potential treatments thus include nonspecific "gamma globulin" or IVIG treatment, as well as treating patients with antibodies or serum harvested from patients who have survived swine flu infections and generated high levels of antibodies in response.  Potentially, protective monoclonal antibodies could be produced from engineered lymphocytes in the near future.

This is how medicine is supposed to be practiced: with a desperate situation you go beyond the tried-and-true (failing) treatments, and investigate the patients more broadly and try experimental treatments.  The Australians are again on the front lines dealing with this troubling disease.