Jens Walter Lecture

The speaker discusses a research project published in 2015, focusing on studying a non-industrialized microbiome.
The project explored interesting narratives, the process of conducting research, and lessons learned over the years.
The speaker is a gastrointestinal microbiologist intrigued by how gut microbiota impacts health, linking it to the study of non-industrialized populations.

The microbiome plays a critical role in human biology, providing essential functions such as immune system development and nutrient acquisition.
The gut microbiome is significantly tied to various chronic diseases, including colon cancer, heart disease, and type two diabetes, which account for a large percentage of deaths in industrialized societies.
The field of microbiome research is gaining traction due to observed increases in these diseases over the past century, prompting investigations into the environmental and lifestyle changes that may have influenced microbial health.

Epidemiological studies suggest a "disappearing microbiota" hypothesis, proposing that modern lifestyles might lead to a loss of beneficial microbial communities, resulting in an increased susceptibility to diseases.
Factors such as diet, antibiotic use, and hygiene practices have been identified as contributing to shifts in the microbiome.
To test this hypothesis, the research aimed to compare a non-industrialized population with a modern population, specifically focusing on Papua New Guinea.

The speaker describes Papua New Guinea as a culturally diverse country, with unique tribal communities and minimal exposure to modern lifestyles in certain regions.
Rural populations rely on subsistence agriculture, untreated drinking water, extended breastfeeding, and long-standing dietary traditions, creating a rich microbial environment.
The study involved collecting fecal samples from two tribes: the Asaro in the highlands and another tribe in the lowlands.

A team of researchers collaborated to analyze the gut microbiome of individuals from Papua New Guinea compared to a controlled group from Prescott, USA.
The challenges of obtaining samples and navigating ethical approvals were highlighted, demonstrating the complexities of international research.
Various methods including next-generation sequencing were used to assess the diversity and composition of microbial communities in the samples.

The study identified approximately 1500 operational taxonomic units (OTUs), with rural Papua New Guinea showing higher bacterial diversity compared to US samples.
Enhanced similarity between individuals within the non-industrialized population was noted, indicating a more consistent microbiome.
Heat maps showed around 50 species absent in the US microbiota, supporting the missing microbiota hypothesis and highlighting significant compositional differences.

Discussions expanded to include ecological factors influencing microbial diversity: selection, dispersal, and the impact of environmental factors.
Dispersal, or the movement of microbes among individuals, significantly shapes local microbiomes, particularly in non-industrialized settings where communal living prevails.
The conclusion drawn states that microbiomes in industrialized societies are less diverse due to limited microbial sharing compared to those in non-industrialized contexts.

After initial submission and rejection from Cell Host Microbe due to perceived confounding factors, the paper was resubmitted to Cell Reports after an influential conference presentation.
Despite initial setbacks, the research gained traction and ultimately received recognition within the field, illustrating the unpredictable nature of scientific publication.
The final paper received over 605 citations, affirming the relevance and impact of the findings in the discourse surrounding microbiomes.

The research not only provided insights into microbiome diversity but also elicited discussions about chronic disease trends linked to modernization and industrial lifestyles.
It emphasized the need for adaptive research strategies, persistence through setbacks, and the role of luck in scientific success.
Key messages included the importance of clear scientific objectives, understanding literature, effective communication at conferences, and leveraging social media for outreach.
Future research aims to explore ways microbiome restoration could mitigate chronic diseases, balancing the need for sanitation and understanding of microbial health.