Multi-omics approaches to investigate the role of Blastocystis in health and disease

Blastocystis is a protozoan anaerobe that inhabits the gastrointestinal (GI) tract of

humans and other animals. It is extremely genetically diverse and has a complicated

relationship with pathogenicity. In humans, most Blastocystis-positive cases are

asymptomatic. However, some studies have found an association between

Blastocystis and GI symptoms. So, what role does Blastocystis play in the gut? The

gut microbiome is an extremely diverse community of over 100 trillion microorganisms,

with bacteria hugely dominant. Understanding the relationship between Blastocystis

and the bacterial component of the gut microbiome could help elucidate understanding

of Blastocystis' role in causing GI symptoms. Does Blastocystis have an impact on the

gut microbiome, which affects GI health?

Using a range of molecular biology, biochemical, and epidemiological techniques,

this study delves into the epidemiology of Blastocystis in South East England. It also

investigates the impact of Blastocystis on the gut microbiome and gut metabolome,

particularly in relation to irritable bowel syndrome (IBS) and ulcerative colitis (UC).

The study further explores the effects of IBS treatment with antibiotics on the gut

microbiome and metabolome and how these factors influence Blastocystis presence.

Additionally, it examines Blastocystis' impact on the gut metabolome in diverse

regions such as Thailand, Turkey, and Korea.

Significant differences in metabolome composition were detected in Thailand, Turkey

and Korea, and minimal differences were detected in South East England's cohort

which microbiome and metabolome composition was studied. No differences in

microbiome composition between Blastocystis subtypes or between Blastocystis and

different risk factors were detected. The antibiotic course correlated with a decline in

4

microbial diversity, Blastocystis presence, and a change in the gut metabolome. Both

IBS and UC affected gut microbiome composition regardless of Blastocystis

colonisation.

This study marks a significant milestone as the first to directly investigate the

relationship between Blastocystis and the gut metabolome. It also stands as the

inaugural epidemiological study of Blastocystis in South East England. Moreover, it is

the first comprehensive study to explore the impact of Blastocystis on the gut

microbiome, metabolome, and IBS, as well as the effects of antibiotic treatment for

IBS on the gut microbiome and its influence on Blastocystis presence.