Are lab mice too cold? Why it matters for science

http://www.eurekalert.org/pub_releases/2016-04/cp-alm041216.php

Public Release: 19-Apr-2016
Are lab mice too cold? Why it matters for science
Cell Press

A typical mouse laboratory is kept between 20 [68F] and 26 [78.8F] degrees C, but if the mice had it their way, it would be a warm 30 degrees C [86F]. While the mice are still considered healthy at cooler temperatures, they expend more energy to maintain their core temperature, and evidence is mounting that even mild chronic cold stress is skewing results in studies of cancer, inflammation, and more. Researchers review the evidence April 19 in Trends in Cancer.

"Most people only look at results from experiments at standard lab temperatures," says Bonnie Hylander, an immunologist at the Roswell Park Cancer Institute. "They're not necessarily aware that if you repeat the experiments with mice at a different temperature, you might get a different outcome."

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A few years ago, Hylander and Elizabeth Repasky, an immunologist at the Roswell Park Cancer Institute, along with their colleagues, began investigating the effects of cold stress on the mouse immune system's ability to fight tumors. As the team revealed in 2013, lab mice do a better job of fighting cancer naturally when they're nice and warm. Tumors grew slower and were less likely to metastasize compared to mice kept at standard lab temperatures. The warmer mice also responded better to chemotherapies.

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Studies in fields ranging from obesity research to neurobiology have shown that housing temperature can alter study results in mice. "While animal physiologists have recognized the potential of this problem for some time, we were surprised that essentially no work was done on cancer models.

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