Cytokines and acute phase proteins as markers for infection in harbour porpoises (Phocoena phocoena)

Abstract

Impairment of immune function and inflammatory incidences in marine mammals are generally difficult to detect (King et al. 1996, Zeneto-Savin et al. 1997, Funke et al. 2003). Therefore, markers for inflammation would be helpful to monitor the health status of animals kept in captivity and of free-ranging animals. It is well established that initiation and progression of an immune response are regulated by cytokines (Lucey et al. 1996, Elenkov and Chrousos 1999, Kidd 2003). During an immune reaction, pro- and anti-inflammatory cytokines are distinguished (Tizard 1996, DiPiro 1997). In the beginning of an immune response, proinflammatory cytokines, such as interleukin (IL)-1, IL-6, IL-8 and tumor necrosis factor (TNF), are produced predominantly by macrophages and monocytes and can be used to detect subclinical infections (King et al. 1996, Tizard 1996, DiPiro 1997, Funke et al. 2003). Further progression involves T helper (Th) cells (Lucey et al. 1996, Mosmann and Sad 1996, Elenkov and Chrousos 1999, Singh et al. 1999, Kidd 2003). Th1 cells secrete the proinflammatory cytokines interferon (IFN), IL-2, and TNF.