I asked around for some more take-home messages from a couple of the keynote speakers present at the
2nd International Blastocystis Conference last month in Bogotá. Here's a summary:
Kevin Tan:
- Blastocystis is a species complex and as such, it is difficult to generalize on its roles in health and disease.
- Studies are revealing that
intra-subtype variations are associated with different phenotypes, so it is
likely that we will require more resolution (allelic) when studying the effects
of Blastocystis on the host.
- Recent metagenomics studies
on stools of healthy individuals associate the presence of Blastocystis with
a diverse bacterial microbiota, but more studies are required on diseased
groups to identify their possible associations with rare/ pathogenic isolates
(e.g. ST7 isolates).
- Recent work on rodent models
are shedding light on possible pathogenic effects of acute Blastocystis infections.
- More studies on the cell
and molecular biology of Blastocystis are required to better understand
the molecular basis for Blastocystis-host interactions (identify virulence
factors, adaptation strategies etc).
- It is very likely that more surprises are in store for the curious and observant Blastocystis researcher!
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| Kevin Tan giving his keynote |
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| Kevin Tan taking questions - here probably expanding on Blastocystis ploidy... |
Andrew Roger:
- We shouldn’t try to generalize about characteristics of
‘Blastocystis’ based on studies of individual isolates. This is a
category error — Blastocystis comprises many many different organisms with
different genetic makeups. There is variation not just between subtypes,
but within subtypes. So we shouldn’t say “Blastocystis is a
commensal/parasite” because different Blastocystis isolates could be
commensals or parasites depending on the host, the genetic makeup of the
parasite and the microbiota with which they interact.
- In microbiome studies, colonization with Blastocystis
in general seems to correlate with a different composition of the prokaryotic
microbiota in hosts.
- We know virtually NOTHING about the basic cell biology
of Blastocystis (Kevin Tan’s group is making important inroads into
understanding this).
- We know virtually NOTHING about how Blastocystis
interacts with (or responds to) other microbes and the host immune system.
- There may be an important impact of host diet on
Blastocystis colonization and ‘behaviour'.
- The diversity of Blastocystis in humans and animals is
huge — new lineages are being continuously revealed.
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| Andrew Roger about to give his keynote |
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| Andrew Roger taking questions from the audience |
