Social Parasites: Trypanosomes Co-operate

We usually don’t think about the organisms that live on us, or in us, communicating or co-operating with each other. At least, I don’t. They use nutrients to grow, to reproduce, to spread. They may move around; they may mate, or simply divide by binary fission, but one hardly imagines them saying to each other “let’s go see what we can find over there,” or “we’ll work together to get past these host defenses.”

Of course they don’t literally have these conversations, but scientists are discovering that many organisms, even single celled ones, communicate with each other for the benefit of all. A recent article published by Medical News Today describes new research findings for Trypanosoma brucei, agent of African sleeping sickness.  Researchers have found that individuals of this species work together as a group to exploit their environment and likely do so to survive and invade tissues in the host.

That’s fascinating on several levels. First, it casts the enemy in a new light – it makes the invader somehow more easily understood from an anthropomorphic point of view (one should not attribute human qualities to protozoa, but it does feel comfortable - more comprehensible -  to think of them in these terms sometimes). It implies, too, that these life forms don’t get enough respect for their complexity and sophistication.

Second, it reminds us that there is still much we don’t know about many familiar species. African sleeping sickness has been a major health concern for well over a hundred years, and yet we’re only starting to understand the organisms that cause it. Finally, as the researchers have pointed out, knowledge like this may lead to better ways to prevent or treat the infection. Know the enemy.

Did I mention they’re beautiful? This is how they can look if they're co-operating on culture media.

[caption id="attachment_223" align="aligncenter" width="300" caption="Creative Commons Attribution 2.5, Oberholzer et al."][/caption]

Oberholzer M, Lopez MA, McLelland BT, Hill KL, 2010 “Social Motility in African Trypanosomes.” PLoS Pathog 6(1): e1000739. doi:10.1371/journal.ppat.1000739