Immunity can be lymph-less

Researchers have overturned the long-standing notion that lymph nodes are always necessary for launching the mammalian immune response.

Fluorescently-labeled mouse liver Image: Burkhard Becher

According to a linkurl:study;http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1000109 published in this month's issue of PLoS Biology, in the absence of lymph nodes, cell-mediated immunity can be activated in the liver. The findings undercut immunology "dogma," which says the immune response is always initiated within secondary lymphoid organs, such as lymph nodes and spleen, said linkurl:Daniel Kreisel,;http://www.cardiothoracicsurgery.wustl.edu/Faculty/FacultyCV.asp?DrID=411 a transplant immunologist at Washington University in St. Louis who did not participate in the study. "This paper shows that T cell-mediated responses can be initiated independent of secondary lymphoid organs." The assumption that lymph nodes necessarily underlie immunity stems from experiments with mutant mice that lack lymph nodes, known as Alymphoplasia (aly/aly) mutants. These mice fail to display proper antibody and cell-mediated immune responses, a problem which scientists believed stemmed from the...