November 2, 2009

Speeding discovery in neurological disease: The nose knows

Trying to understand neurological disease by studying cells in a dish is limited by the availability of the right cells. For years, researchers have relied on postmortem human brains as a source for schizophrenia-affected neurons. Now, Johns Hopkins scientists have developed a novel method via nasal biopsies of schizophrenia patients, establishing a faster way to make neurons in a dish for further study.

“Nasal biopsies are more efficient than the standard skin biopsy for use in conventional methods of generating induced pluripotent stem cells,” said Akira Sawa, an associate professor and director of the Program in Molecular Psychiatry at the Johns Hopkins School of Medicine. “Our process takes two weeks, compared to the 12 months it might take to generate cells otherwise.”

Taking a tiny bit of skin tissue from inside the nose, the researchers then grow that sample of cells in a dish. Nasal biopsies, unlike standard skin biopsies taken from an arm, contain neural stem cells, which, according to Sawa, grow more easily in a dish and thus provide more cells with which to work. The team then separates the neural cells from the other cells in the biopsy with molecular tricks that they plan to patent.

“Critics have suggested that neuronal cells grown from the nose are not the same as those isolated from the brain,” Sawa said. “But we’ve tested them, and they share many of the same markers and respond similarly to stimulation.”

The team said it hopes that these cells will be used by many to study conditions such as schizophrenia, mood disorders and other neuropsychiatric disorders, and provide a system to tease apart molecular mechanisms underlying the disease. The cells also might be used to test responses to drugs and potential treatments.

The work with nasal biopsies was presented at the annual meeting of the Society for Neuroscience, held Oct. 17 to 21 in Chicago.