Thanks for that article. It also links to this study from 2005 showing a correlation between accute cooling of the feet and the onset of cold symptoms in humans. The studies on cell apoptosis were attempting to show why (according to the nature article). Interesting that the original article doesn't mention this 2005 study.

https://academic.oup.com/fampra/article-lookup/doi/10.1093/f... https://www.ncbi.nlm.nih.gov/pubmed/16286463?dopt=Abstract&h...