Doctoral Dissertation Research: The influence of the social environment on the infant skin microbiome

皮肤微生物组-生活在人体表面的微生物的集合-在调节免疫系统方面起着关键作用，但人们对婴儿在早期如何获得皮肤微生物知之甚少。由于微生物在人与人之间传播，而人类婴儿期是高度社会化的，因此与看护者的互动可能是婴儿皮肤微生物组发育的关键组成部分。这个博士论文项目研究了婴儿社交网络和婴儿与他们的照顾者之间的特定互动如何影响生活在婴儿皮肤上的微生物的多样性。该项目的结果揭示了社会行为与婴儿皮肤微生物组之间未充分研究的关系，并为未来将早期微生物暴露与特定生理结果联系起来的研究奠定了基础。研究参与者，包括母亲和其他照顾者，将收到基于研究结果的个性化报告，包括有关他们的社交网络以及他们的皮肤微生物组结构的信息，以及如何与婴儿进行比较。该项目还有助于通过培训来自STEM研究中代表性不足的群体的本科生，在皮肤微生物组实验室方法和统计分析方面提高多样性和包容性。与其他类人猿不同，人类母亲需要额外的照顾者，如祖父母和年长的兄弟姐妹，来长期帮助照顾婴儿。常见的婴儿护理做法，包括抱和抱，促进了护理人员和婴儿之间的直接皮肤接触，这表明皮肤微生物有机会与婴儿分享。该项目将研究社交活动如何影响婴儿皮肤微生物组，重点是婴儿皮肤及其护理人员之间的微生物相似性。研究人员将从婴儿、母亲和其他护理人员那里收集皮肤拭子样本，并使用微生物基因测序来表征和比较样本中存在的皮肤微生物。照顾者将完成问卷调查，询问他们与婴儿进行身体接触的具体做法的频率。研究人员将利用这些数据来生成描述婴儿与其照顾者之间社会关系的社交网络，从而提出皮肤微生物与婴儿共享的潜在途径。该项目提供了一个新的视角来看待社会环境对婴儿的益处，其结果将突出社会环境在将早期生命微生物暴露与健康结果联系起来方面所起的作用。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The skin microbiome — the collection of microorganisms that live on the surface of the human body — plays a critical role in regulating the immune system, yet little is known about how infants first acquire skin microbes in early life. Since microbes are transmitted between people, and human infancy is highly social, interactions with caregivers may be a critical component of infant skin microbiome development. This doctoral dissertation project examines how infant social networks and specific interactions between infants and their caregivers influence the diversity of microbes living on infants’ skin. Results of this project shed light on the understudied relationship between social behaviors and the infant skin microbiome, as well as laying the foundation for future studies that connect early life microbial exposures to particular physiological outcomes. Study participants, including mothers and other caregivers, will receive personalized reports based on research results, including information about their social networks as well as the structure of their skin microbiome and how it compares to that of their infant. This project also contributes to enhancing diversity and inclusion by training undergraduate students from groups underrepresented in STEM research in skin microbiome laboratory methods and statistical analyses. The project also has public health translational potential with respect to infant wellbeing.Unlike other great apes, human mothers rely on additional caregivers, such as grandparents and older siblings, for long-term assistance with infant care. Common infant care practices, including holding and carrying, promote direct skin-to-skin contact between caregivers and infants, suggesting opportunities for skin microbes to be shared with infants. This project will investigate how social caregiving influences the infant skin microbiome, with an emphasis on the microbial similarity between the skin of infants and their caregivers. Researchers will collect skin swab samples from infants, mothers, and additional caregivers, and use microbial gene sequencing to characterize and compare the skin microbes present in the samples. Caregivers will complete questionnaires that ask about the frequency of specific practices that put them in physical contact with infants. The researchers will use these data to generate social networks that describe social relationships between infants and their caregivers, suggesting potential routes through which skin microbes are shared with infants. This project offers a novel perspective on the benefits of social caregiving to infants, and the results will highlight the role that the social environment plays in linking early life microbial exposures to health outcomes.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.