Dolphins, whales and other cetaceans are susceptible to many of the same health hazards as humans including mercury, brevotoxin (e.g. Red Tide), and lobomycosis. They also serve as important sentinel species to highlight concerns relevant to environmental and public health. Yet understanding how these aquatic mammals fight disease-causing pathogens, how they adapt to changing pathogenic threats, and how their immune responses are triggered has been challenging.
Two recent papers by Florida Atlantic University researchers reveal how cetaceans compete for survival in an evolutionary “arms race” with changing pathogen communities. As pathogenic threats and the risk of infectious disease changes, whales and dolphins must adapt to those changes. The question today is can they adapt fast enough?
In a groundbreaking study published in PLOS One , researchers from FAU’s Harbour Branch Oceanographic Institute found that cetaceans use several strategies for success in this evolutionary arms race. The immune response in vertebrates is mediated through a series of rapidly evolving genes called the major histocompatibility complex or MHC. The MHC acts as an early warning system against pathogens that not only sounds the alarm, but also activates an armed response. In order to do this, MHC proteins need to be able to distinguish “friend” from “foe” at a molecular level. Similar to a lock-and-key mechanism, an individual’s MHC ‘lock’ has to be able to bind to a pathogen’s peptide ‘key’ to launch the defence sequence. MORE