Tuesday, July 26, 2022

Scientists expand entomological research using genome editing


Research team develops functional annotation workflow for genome sequencing of insects

Peer-Reviewed Publication

HIROSHIMA UNIVERSITY

Overview of the functional annotation workflow, Fanflow4Insects 

IMAGE: FANFLOW4INSECTS CONSISTS OF THREE PIPELINES. view more 

CREDIT: HIDEMASA BONO, HIROSHIMA UNIVERSITY (CC-BY 4.0)

Genome sequencing, where scientists use laboratory methods to determine a specific organism’s genetic makeup, is becoming a common practice in insect research. A greater understanding of insect biology helps scientists better manage insects, both those that are beneficial to the ecosystem and those that damage the food supply and threaten human health by carrying diseases.

Researchers have developed a work-flow method, called Fanflow4Insects, that annotates gene functions in insects. In functional annotation, scientists collect information about a gene's biological identity. The team’s new method uses transcribed sequence information as well as genome and protein sequence databases. With Fanflow4Insects, the team has annotated the functional information of the Japanese stick insect and the silkworm, including gene expression as well as sequence analysis. The functional annotation information that their workflow provides will greatly expand the possibilities of entomological research using genome editing.

The team, with scientists from Hiroshima University, Tokyo University of Agriculture and Technology, and RIKEN Center for Integrative Medical Sciences, has published their Fanflow4Insects method on June 27 in the journal Insects.

Insects are so diverse and abundant that scientists need a way of studying them on a large scale. This is what led scientists to begin work on sequencing the genome of insects. As of May 2022, scientists had decoded and registered the genomes of around 3000 insect species. They are also using long-read sequencing technology to further accelerate the pace of insect genome sequencing.

Next-generation sequencing has made it easier for researchers to decode the genomes of numerous insects along with their transcript sequences. However, the biological interpretation of these sequences remains a primary bottleneck of transcriptome analysis. The transcriptome is the sum of an organism’s RNA molecules. Transcriptome analysis is an important first step in functional annotation, which serves as an important clue for selecting genome editing targets.

Because some insects have genomes larger than the human genome, the difficult process of whole-genome sequencing is even more complicated. So scientists are using transcriptome sequencing with next-generation sequencing technology, also called RNA sequencing, as a tool for evaluating large genome-size insects. With this powerful tool, scientists can efficiently identify tens of thousands of possible genes in a specific tissue by assembling tens of millions of reads. They then assemble the gene sequences into transcriptional units for identification. But this type of analyses is dependent upon the scientists having access to comprehensive datasets and their functional annotation. Databases do exist, but they are unable to keep pace with the increase in insect genome sequencing.

As transcriptome analysis becomes more popular, many research groups are running their own pipelines, with the information regarding the transcription units from various studies being reported on a study-by-study basis. These pipelines are sets of algorithms used to processes the genome sequencing data. But scientists need a way to integrate the functional annotation from all the different groups doing this type of research into public databases.

In this current study, the research team used their newly developed Fanflow4Insects to create a functional annotation pipeline for the silkworm. Then the researchers also tested Fanflow4Insects for the transcriptomes of the Japanese stick insect. “Functional annotation is one of the most important processes to accelerate the selection of target genes once genome or transcriptome of the target organism is decoded. The functional annotation information obtained by the workflow Fanflow4Insects will greatly expand the possibilities of entomological research using genome editing,” said Hidemasa Bono, a professor with the Graduate School of Integrated Sciences for Life at Hiroshima University, and the first and corresponding author on the paper.

The Fanflow4Insects workflow for insects has been openly developed on GitHub, and is freely accessible. In conjunction with the functional annotation derived from expression, the data from Fanflow4Insects can be applied to the comparative study of insects with distinct phenotypes. “Using Fanflow4Insects, we are going to annotate insects that produce useful substances. The ultimate goal of this study is to make it possible to design molecular networks in insects using computer simulation,” said Bono.

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The research team includes Hidemasa Bono, Hiroshima University; Takuma Sakamoto and Hiroko Tabunoki, Tokyo University of Agriculture and Technology; and Takeya Kasukawa, RIKEN Center for Integrative Medical Sciences.

This research was funded by a Japan Society for the Promotion of Science Kakenhi grant, an open innovation platform for industry–academia co-creation (COI-NEXT), Japan Science and Technology Agency, and the ROIS-DS-JOINT.

About Hiroshima University

Since its foundation in 1949, Hiroshima University has striven to become one of the most prominent and comprehensive universities in Japan for the promotion and development of scholarship and education. Consisting of 12 schools for undergraduate level and 4 graduate schools, ranging from natural sciences to humanities and social sciences, the university has grown into one of the most distinguished comprehensive research universities in Japan.
English website: https://www.hiroshima-u.ac.jp/en

Historical mistrust in government, health care industry contributes to COVID-19 vaccine hesitancy for African Americans

MU researcher studies social, structural determinants of health that feed vaccine hesitancy, worsen health disparities for African Americans.


UNIVERSITY OF MISSOURI-COLUMBIA

image: Vaccine 
Credit: University of Missouri

COLUMBIA, Mo. – While African Americans have disproportionately higher COVID-19 infection and mortality rates compared to white individuals, they also have disproportionately lower COVID-19 vaccination rates, which is partially fueled by vaccine hesitancy.

In an effort to address health disparities that negatively impact African Americans, MU’s Wilson Majee led a study to better understand the factors that contribute to COVID-19 vaccine hesitancy among African Americans. He found compounding factors, including historical mistrust in government and personal experiences of racism within the health care system, contribute to COVID-19 vaccine hesitancy for African Americans.

Majee interviewed church leaders, lifestyle coaches and participants of Live Well by Faith, a community faith-based wellness program run by the Boone County Health Department that promotes healthy living and addresses chronic health conditions in predominantly African American communities in Boone County, Missouri. Both historical mistrust in government and personal experiences of racism within the health care system were common themes among African American community members for not wanting to receive the COVID-19 vaccine.

“The Tuskegee Syphilis Study was repeatedly mentioned as a popular example of unethical medical treatment toward African Americans by the federal government, and once that trust is lost, it can be hard to regain even as time goes on,” said Majee, an associate professor in the MU School of Health Professions. “One respondent mentioned the common reminder from the federal government of never forgetting the tragic events of September 11, 2001, yet African Americans are expected to forget the unethical research practices and the history of injustice and racism from their own federal government.”

Majee also told the story of another respondent who reflected on his own personal experience in the health care industry after he tested positive for COVID-19.

“This elderly man went to the hospital but was sent home, and after his health declined, he went back to the hospital but was sent back home again,” Majee said. “When he went back a third time, he was told they had made a mistake and he was given a hospital bed so he could be monitored, and he could not help but wonder if his experience would have been different if he was not Black?”

Other factors contributing to COVID-19 vaccine hesitancy included how fast the vaccine was developed, a lack of Black physicians providing the vaccines and misinformation spread on social media.

Majee added social determinants of health, including that African Americans tend to be poorer and have less access to education, health care and healthy foods, as well as structural determinants of health, including that African Americans tend to be affected by racism in the housing, education, employment and health care industries, all compound together to contribute to worse health outcomes for African Americans.

“African Americans are more likely to have lower-income, in-person jobs at crowded places that cannot accommodate work-from-home or social distancing, so they are more likely to be exposed to and infected by COVID-19,” Majee said. “Combine that with African Americans already being poorer and less likely to be able to afford quality health insurance, the historical mistrust in government and personal negative experiences with the health care industry, and you quickly see how all these factors start to work together to negatively impact health outcomes for African Americans.”

Community wellness programs like Live Well by Faith play a key role in helping to address these inequities, Majee said. Receiving accurate information about the COVID-19 vaccine from trusted community members, such as African American church leaders and lifestyle coaches, played a big role in promoting positive health outcomes.

“African American members of the congregation at Black churches believed in the information they were receiving because it was coming from people they trusted that looked like themselves,” Majee said. “The key about the Live Well by Faith program is that is it rooted in the community, and we saw it was helpful in getting more African Americans to receive the COVID-19 vaccine.”

Majee’s main research goal is to find ways in which those with power, including local, state and federal governments, church leaders, researchers and adult role models, can distribute resources that engage vulnerable populations in their communities.

“My passion is to empower people in resource-limited communities by listening to their ideas and allocating resources to develop interventions that meet the needs of struggling people,” Majee said. “There is a great need to elevate the health of minorities, as the disparities are huge and will continue to grow if we fail to act now.”

“The past is so present: Understanding COVID-19 vaccine hesitancy among African American adults using qualitative data” was published in Journal of Racial and Ethnic Health Disparities. Co-authors on the study include MU’s Adaobi Anakwe, Kelechi Onyeaka and Idethia Harvey.

Health Care Experiences of Patients Discontinuing or Reversing Prior Gender-Affirming Treatments

Key Points

Question  What are the health care experiences of adults undergoing medical and/or surgical detransition?

Findings  In this qualitative study, 28 adults with heterogenous gender identities were interviewed about their experiences of detransition, including their health care encounters when discontinuing or reversing gender-affirming medical and/or surgical care. A majority of respondents reported no decisional regrets regarding prior gender-affirming interventions; however, participants frequently discussed health care avoidance, clinician stigma, and experiencing clinicians who lacked detransition-related clinical knowledge.

Meaning  These findings suggest that clinicians may be insufficiently knowledgeable to meet the needs of this population, and further research and clinical guidance are required to better support people who detransition after pursuing gender-affirming health care.

Abstract

Importance  Medical education, research, and clinical guidelines are available to support the initiation of gender-affirming care for transgender and nonbinary people. By contrast, little is known about the clinical experiences of those who discontinue or seek to reverse gender-affirming medical or surgical interventions due to a change in gender identity, often referred to as detransition.

Objective  To examine the physical and mental health experiences of people who initiated medical or surgical detransition to inform clinical practice.

Design, Setting, and Participants  Using constructivist grounded theory as a qualitative approach, data were collected in the form of in-depth interviews. Data were analyzed using an inductive 2-stage coding process to categorize and interpret detransition-related health care experiences to inform clinical practice. Between October 2021 and January 2022, individuals living in Canada who were aged 18 years and older with experience of stopping, shifting, or reversing a gender transition were invited to partake in semistructured virtual interviews. Study advertisements were circulated over social media, to clinicians, and within participants’ social networks. A purposive sample of 28 participants who discontinued, shifted, or reversed a gender transition were interviewed.

Main Outcomes and Measures  In-depth, narrative descriptions of the physical and mental health experiences of people who discontinued or sought to reverse prior gender-affirming medical and/or surgical interventions.

Results  Among the 28 participants, 18 (64%) were assigned female at birth and 10 (36%) were assigned male at birth; 2 (7%) identified as Jewish and White, 5 (18%) identified as having mixed race and ethnicity (which included Arab, Black, Indigenous, Latinx, and South Asian), and 21 (75%) identified as White. Participants initially sought gender-affirmation at a wide range of ages (15 [56%] were between ages 18 and 24 years). Detransition occurred for various reasons, such as an evolving understanding of gender identity or health concerns. Participants reported divergent perspectives about their past gender-affirming medical or surgical treatments. Some participants felt regrets, but a majority were pleased with the results of gender-affirming medical or surgical treatments. Medical detransition was often experienced as physically and psychologically challenging, yet health care avoidance was common. Participants described experiencing stigma and interacting with clinicians who were unprepared to meet their detransition-related medical needs.

Conclusions and Relevance  This study’s results suggest that further research and clinical guidance is required to address the unmet needs of this population who discontinue or seek to reverse prior gender-affirming interventions.

READ ON:  Health Care Experiences of Patients Discontinuing or Reversing Prior Gender-Affirming Treatments | Health Disparities | JAMA Network Open | JAMA Network

Prevalence of Mental Health Problems in Transgender Children Aged 9 to 10 Years in the US, 2018

JAMA Netw Open. 2022;5(7):e2223389. doi:10.1001/jamanetworkopen.2022.23389

Research Letter 
Diversity, Equity, and Inclusion
July 22, 2022
Introduction

Research into the mental health of transgender and gender diverse (henceforth, transgender) young people points to concerning levels of depression, anxiety, and other mental health issues.1-5 Much of this research has focused on transgender young people attending specialist gender clinics1,3-5 or recruited via community-based convenience sampling.2 Although such studies have made important contributions to understanding the mental health of transgender young people, they have critical limitations and potential biases. Clinical samples may misestimate the prevalence and severity of mental health problems, while convenience samples may experience selection bias. Both cases lead to challenges in generalizing findings to the general population. To address these shortcomings, research using representative community samples of transgender young people is required.

Methods

This cohort study compared mental health outcomes between transgender and cisgender children aged 9 to 10 years who completed baseline assessment in the Adolescent Brain Cognitive Development study, which recruited more than 11 000 children across the US using multistage probability sampling with the aim of obtaining a representative sample of the US population. The Adolescent Brain Cognitive Development study was approved by the institutional review board at the University of California, San Diego. Parents provided informed consent and children additionally gave their assent. Using the parent-reported Child Behavior Checklist, we assessed standardized T scores for 6 Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5)–oriented subscales (depressive/anxiety/somatic/attention-deficit/hyperactivity disorder/oppositional defiant/conduct problems) and suicidality. Data were analyzed using Stata statistical software version 17 (StataCorp). We calculated the odds ratio using multilevel logistic regression. We did not set any arbitrary cut off defining a priori level of significance based on best practice. We have used odds ratios to report the effect size and confidence interval to report the variability of the estimate in the general population. Data were analyzed in March 2022. This study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline. Additional methods are outlined in the eMethods in the Supplement.

Results

This analysis included 7169 children and compared transgender (58 participants) and cisgender (7111 participants) children who understood and answered the question “Are you transgender?” The 4692 participants who reported not understanding this question were excluded along with 17 who did not record a response. The mean (SD) age of participants was 10.03 (0.62) years. Transgender children represented 0.8% (weighted) of respondents and for all 6 subscales recorded higher mean T scores, although these were all in the reference range and the standardized mean difference in each case was small (Table). We also determined the proportion of cisgender and transgender children who scored in the borderline or clinical range (T ≥65) for each subscale (Table). The odds ratio of transgender children being in this range was increased for all 6 subscales (range, 1.57 [95% CI, 0.50-4.91] to 3.13 [95% CI, 1.46-6.71]) as well as for suicidality (odds ratio, 5.79 [95% CI, 2.08-16.16]), although the results for attention-deficit/hyperactivity disorder and oppositional defiant problems were not statistically significant (Table).

Discussion

Previous research using clinical samples of transgender children aged 5 to 11 years4 reported lower rates of depression and anxiety than we observed in this cohort study. Apart from methodological differences in assessing mental health, a possible reason for this disparity is that transgender children attending specialist gender clinics are likely to have support from their families (a key protective factor for the mental health of transgender young people); in comparison, many transgender children in the general population lack parental support for their gender.

Previous studies using clinical and convenience samples of transgender adolescents had higher rates of depression and anxiety compared with our sample.1-3,5 This is consistent with earlier clinic-based observations that transgender children have lower rates of anxiety and depression compared with transgender adolescents,4 which may be explained by observations from the general population that depression and anxiety more frequently develop during adolescence.6

The small number of transgender participants is a limitation of our study, as is the exclusion of many children who did not understand the question on gender identity. Nevertheless, this is, to our knowledge, the first study to report rates of DSM-5–related problems using a representative population sample of transgender children. Our findings suggest that by 9 to 10 years of age transgender children already show increased susceptibility to mental health problems compared with their cisgender peers, which has important public health implications. Whether this is due to stigma, minority stress, discrimination, or gender dysphoria is unclear, but providing appropriate mental health supports to this vulnerable group is paramount.

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Article Information

Accepted for Publication: June 6, 2022.

Published: July 22, 2022. doi:10.1001/jamanetworkopen.2022.23389

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2022 Russell DH et al. JAMA Network Open.

Corresponding Author: Kenneth C Pang, PhD, Murdoch Children’s Research Institute, 50 Flemington Rd, Parkville, VIC 3052, Australia (ken.pang@mcri.edu.au).

Author Contributions: Dr Pang and Mr Russell had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Coghill, Pang.

Acquisition, analysis, or interpretation of data: All authors.

Drafting of the manuscript: Russell, Pang.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Russell, Hoq, Pang.

Obtained funding: Pang.

Administrative, technical, or material support: Pang.

Supervision: Coghill, Pang.

Conflict of Interest Disclosures: Mr Russell reported being a member of the Australian Professional Association for Trans Health. Dr Coghill reported receiving personal fees from Servier, Takeda, Novartis, Oxford University Press, Cambridge University Press, and Medice outside the submitted work. Dr Pang reported being a member of the World Professional Association for Transgender Health, a member of the Australian Professional Association for Trans Health, and a member of the editorial board of the journal Transgender Health. No other disclosures were reported.

Funding/Support: Mr Russell is supported through an Australian Government Research Training Program Scholarship. No other funding relates to the study. Dr Pang is supported by funding from the Hugh Williamson Foundation, the Royal Children’s Hospital Foundation and the National Health and Medical Research Council.

Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

References
1.
Connolly  MD, Zervos  MJ, Barone  CJ  II, Johnson  CC, Joseph  CL.  The mental health of transgender youth: advances in understanding.   J Adolesc Health. 2016;59(5):489-495. doi:10.1016/j.jadohealth.2016.06.012PubMedGoogle ScholarCrossref
2.
Strauss  P, Cook  A, Winter  S, Watson  V, Wright-Toussaint  D, Lin  A., Trans-pathways: the mental health experiences and care pathways of trans young people-summary of results. Telethon Kids Institute. 2017. Accessed August 20, 2021. https://www.telethonkids.org.au/projects/past/trans-pathways/
3.
Olson  J, Schrager  SM, Belzer  M, Simons  LK, Clark  LF.  Baseline physiologic and psychosocial characteristics of transgender youth seeking care for gender dysphoria.   J Adolesc Health. 2015;57(4):374-380. doi:10.1016/j.jadohealth.2015.04.027PubMedGoogle ScholarCrossref
4.
Holt  V, Skagerberg  E, Dunsford  M.  Young people with features of gender dysphoria: demographics and associated difficulties.   Clin Child Psychol Psychiatry. 2016;21(1):108-118. doi:10.1177/1359104514558431PubMedGoogle ScholarCrossref
5.
Khatchadourian  K, Amed  S, Metzger  DL.  Clinical management of youth with gender dysphoria in Vancouver.   J Pediatr. 2014;164(4):906-911. doi:10.1016/j.jpeds.2013.10.068PubMedGoogle ScholarCrossref
6.
Kessler  RC, Berglund  P, Demler  O, Jin  R, Merikangas  KR, Walters  EE.  Lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the National Comorbidity Survey Replication.   Arch Gen Psychiatry. 2005;62(6):593-602. doi:10.1001/archpsyc.62.6.593
ArticlePubMedGoogle ScholarCrossref

Staffing Patterns in US Nursing Homes During COVID-19 Outbreaks

Key Points

Question  What is the association between severe COVID-19 outbreaks and US nursing home staffing patterns?

Findings  In this cohort study of 2967 nursing homes in 2020, owing to increased absences and departures, there were statistically significant declines in staffing levels during a severe COVID-19 outbreak that remained statistically significantly reduced 16 weeks after the outbreak’s start. Facilities temporarily increased hiring, contract staff, and overtime to bolster staffing during outbreaks, but these measures did not fully replace lost staff, particularly certified nursing assistants.

Meaning  Considerable staffing challenges suggest a potential need for policy action to ensure adequate staffing levels during nursing home outbreaks to protect resident health.

Abstract

Importance  Staff absences and departures at nursing homes may put residents at risk and present operational challenges.

Objective  To quantify changes in nursing home facility staffing during and after a severe COVID-19 outbreak.

Design, Setting, and Participants  In this cohort study, daily staffing payroll data were used to construct weekly measures of facility staffing, absences, departures, and use of overtime and contract staff among US nursing homes experiencing a severe COVID-19 outbreak that started between June 14, 2020, and January 1, 2021. Facility outbreaks were identified using COVID-19 case data. An event-study design with facility and week fixed effects was used to investigate the association of severe outbreaks with staffing measures.

Exposures  Weeks since the beginning of a severe COVID-19 outbreak (4 weeks prior to 16 weeks after).

Main Outcomes and Measures  Total weekly staffing hours, staff counts, staff absences, departures, new hires, overtime and contract staff hours measured for all nursing staff and separately by staff type (registered nurses, licensed practical nurses, certified nursing assistants), facility self-reported staff shortages, and resident deaths.

Results  Of the included 2967 nursing homes experiencing severe COVID-19 outbreaks, severe outbreaks were associated with a statistically significant drop in nursing staffing levels owing to elevated absences and departures. Four weeks after an outbreak’s start, around when average new cases peaked, staffing hours were 2.6% (95% CI, 2.1%-3.2%) of the mean below preoutbreak levels, despite facilities taking substantial measures to bolster staffing through increased hiring and the use of contract staff and overtime. Because these measures were mostly temporary, staffing declined further in later weeks; 16 weeks after an outbreak’s start, staffing hours were 5.5% (95% CI, 4.5%-6.5%) of the mean below preoutbreak levels. Staffing declines were greatest among certified nursing assistants, primarily owing to smaller increases in new hires of this staff type compared with licensed practical nurses and registered nurses.

Conclusions and Relevance  In this cohort study of nursing homes experiencing severe COVID-19 outbreaks, facilities experienced considerable staffing challenges during and after outbreaks. These results suggest the need for policy action to ensure facilities’ abilities to maintain adequate staffing levels during and after infectious disease outbreaks.

READ / DOWNLOAD: JAMA Health Forum – Health Policy, Health Care Reform, Health Affairs | JAMA Health Forum | JAMA Network

How the intestine replaces and repairs itself

Peer-Reviewed Publication

ROCKEFELLER UNIVERSITY

Small intestine 

IMAGE: A SIDE VIEW OF THE SMALL INTESTINE WITH LYMPHATIC CAPILLARIES IN YELLOW AND INTESTINAL STEM CELLS IN PINK. view more 

CREDIT: ROBIN CHEMERS NEUSTEIN LABORATORY OF MAMMALIAN CELL BIOLOGY AND DEVELOPMENT AT THE ROCKEFELLER UNIVERSITY

To act as a robust barrier against pathogens while also absorbing needed nutrients, the lining of the intestines must regenerate on a daily basis to remain equal to the task. The intestine’s resident stem cells are responsible for meeting this need for constant repair and replenishment, but each stem cell faces decisions that depend on the overall conditions of the intestine and the needs of the moment. Bad decisions and poor coordination could result in intestinal diseases or cancer.

A new study suggests that stem cells are able to integrate cues from their surroundings and coordinate their behavior across the tissue through networks of vasculature in their close vicinity.

Rockefeller scientists found that lymphatic capillaries—fine vessels that transport immune cells and drain fluids from tissues—represent a signaling hub that communicates with stem cells to regulate their activity. With molecular guidance from the lymphatics, the stem cells produce daughter cells to repopulate the intestinal lining or self-renew to restock the stem cell reserve.

The findings, published in the journal Cell Stem Cell, provide new insights about primary intestinal components whose disrupted communication may contribute to intestinal disorders, such as inflammatory bowel disease. “The key to treating these diseases will be to figure out who talks to whom in this ecosystem and how we can reset the communication networks,” says Rachel Niec, a clinical scholar in the laboratory of Elaine Fuchs.

Communications in the crypt

The intestinal stem cells reside in so-called crypts, found at the base of densely packed indentations in the intestinal lining. The stem cells may renew and stay in the crypt, or differentiate into specialized cells, which then migrate out of the crypt to replenish the gut lining. “To understand how stem cells balance self-renewal with differentiation, we needed a more complete picture of crypt niches,” says Marina Schernthanner, a graduate student in the Fuchs lab.

To zoom in on the crypt, the team used a suite of techniques, including single-cell and spatial transcriptomics, which allowed them to identify cell types at specific locations and study their signaling molecules. The results showed that lymphatic capillaries, which form an intimate connection with the stem cells in the crypt, produce a number of proteins known to be important for stem cell functioning.

One previously underappreciated protein, REELIN, emerged as a top candidate for mediating communications between lymphatics and stem cells. By manipulating the amount of REELIN in lab-grown intestinal organoid cultures in some experiments and genetically suppressing it in mice in others, the researchers found that REELIN directly governs the regenerative behavior of intestinal stem cells.

The involvement of the lymphatic system in stem cell functioning is a relatively new concept. A previous study by the Fuchs team revealed that lymphatics are also closely involved with stem cells of the skin and play a key role in hair regeneration. There, however, it is the hair follicle stem cells that signal to lymphatic capillaries. By controlling their interactions with lymphatics, the stem cells synchronize hair regeneration across the tissue. “This suggests that lymphatics may be a conserved feature of stem cell niches, but their relationship to stem cells are likely tailored around the needs of each tissue,” Niec says.