Department Environmental Toxicology

Humpback whale cell lines

Marine mammals accumulate the greatest levels of persistent organic pollutants (POPs) due to their long life, high proportion of body fat, and top position of the marine food chain. Humpback whales (Megaptera novaeangliae) undertake the longest migration known in any mammal and this time period is also associated with voluntary fasting. During their migration they only live of accumulated fat reserves. This adipose tissue acts as temporary buffer for POPs. Our collaboration partner the Southern Ocean Persistent Organic Pollutants Program (SOPOPP) found that single POP concentrations in the blubber of humpback whales increased by up to 50 times between early and late migration. POPs are reactivated and redistributed during long-term fasting periods.

However, measuring the toxicological impact of POPs on wild populations of humpbacks is a challenge in chemical risk assessment. Non-lethal approaches are logistically challenging and very cost intensive.

In collaboration with Griffith University in Australia skin samples of wild animals were taken and the first humpback whale cell lines (HuWa1 and 2) were developed. Further, HuWa cell lines were immortalised to enable long-term maintenance and application. With these cell lines we are no longer dependent on skin biopsies to study the impact of chemicals in vitro. The cells can be used in ecotoxicology and enable rapid and cost- effective toxicity risk assessment. HuWa cell lines are used to investigate and understand the impact of POPs on humpback whales.  

Derived HuWa cell lines are cultured under standard mammalian conditions and were identified as fibroblasts stemming from male individuals with a karyotype of 2n= 44, which has commonly been observed in other baleen whale species e.g., blue whales. Initial toxicity tests indicate a lower sensitivity to the substance DDE than to human cell cultures. DDE is the main metabolite of the well-known insecticide DDT, and builds up in the blubber of whales. These findings show that DDE can have a differing effect on different species.

Publications

Burkard, M.; Whitworth, D.; Schirmer, K.; Nash, S. B. (2015) Establishment of the first humpback whale fibroblast cell lines and their application in chemical risk assessment, Aquatic Toxicology, 167, 240-247, doi:10.1016/j.aquatox.2015.08.005, Institutional Repository