Findings From NIH-Funded Study Could Facilitate Early Treatment of Neonatal Sepsis

Scientists have identified a four-gene signature detectable in newborns’ blood at birth that predicts before symptom onset whether a baby will develop sepsis during the first week of life, according to a study co-funded by the National Institutes of Health’s National Institute of Allergy and Infectious Diseases (NIAID). Sepsis is a potentially life-threatening condition that arises when the body's response to infection injures its own tissues and organs. Using the newly discovered genetic signature to identify newborns who will develop sepsis could facilitate early treatment and obviate the need to give antibiotics to all newborns with suspected sepsis but lacking a definitive diagnosis. The findings were published today in the journal eBioMedicine. 

Two to 3% of newborns globally develop sepsis, and 17.6% of those babies die. The signs of sepsis in newborns—such as irritability, poor feeding and respiratory distress—are common to many illnesses. Consequently, clinicians sometimes misdiagnose newborn sepsis or suspect it too late, leading to death. If a clinician does suspect that a newborn has sepsis, they give the baby antibiotics pending confirmatory laboratory diagnosis of infection. The most common diagnostic technique takes several days, however, and is often inconclusive. As a result, clinicians often must decide between stopping antibiotics early and risking under-treatment, or giving antibiotics based only on a clinical diagnosis and risking serious side effects and development of antimicrobial resistance.

The NIAID-supported study aimed to find a way to accurately predict sepsis in newborns so it can be diagnosed and treated early while avoiding unnecessary antibiotic use. The researchers conducted their study in a subset of 720 initially healthy, full-term newborns who were enrolled in a larger clinical trial at two community health centers in The Gambia, West Africa. Blood was collected from all babies at birth.

Thirty-three infants were hospitalized within the first month of life for clinical signs suggestive of sepsis. Of those, 21 babies were diagnosed with sepsis, including 15 within the first week of life, which is considered early-onset sepsis. Twelve babies were diagnosed with non-septic localized infections. The researchers matched these 33 babies with 33 healthy controls and analyzed their blood to identify genes that were comparatively more active or less active at birth in each of the four groups. Using machine learning methods, the researchers detected four genes that were comparatively more active at birth only in those newborns who developed early-onset sepsis. The four-gene signature was 92.5% accurate at predicting at birth which of the 66 infants would develop early-onset sepsis. 

The researchers tested the predictive accuracy of this gene signature in a different group of 12 infants whose blood had been collected soon after birth. Half had developed early-onset sepsis, while the other half had remained healthy. The four-gene signature predicted sepsis with 83% accuracy in this group. Further research is needed to determine how well the gene signature predicts early-onset sepsis in much larger groups of newborns.

The study was led by Robert E. W. Hancock, Ph.D.; Tobias R. Kollmann, M.D., Ph.D.; Beate Kampmann, M.D., Ph.D.; and Amy H. Lee, Ph.D. NIAID co-funded the study through its Human Immunology Project Consortium (HIPC) and Immune Development in Early Life program. 

The larger study that enrolled the 720 newborns was called Systems Biology to Identify Biomarkers of Neonatal Vaccine Immunogenicity, sponsored by Boston Children's Hospital and funded by NIAID through the HIPC. More information is available in ClinicalTrials.gov at study identifier NCT03246230.

Reference: An et al. Predictive gene expression signature diagnoses neonatal sepsis before clinical presentation. eBioMedicine DOI: 10.1016/j.ebiom.2024.105411 (2024).

by Jeanne Marrazzo, M.D., M.P.H., NIAID Director

The power of word choice is obvious every day in my life as a researcher, clinician, colleague, patient, spouse, and friend. Language can inform, delight and inspire, but it can mislead and wound if words are not chosen carefully. At worst, language can invoke stigma, shame, and even violence, all of which undermine NIAID’s mission as part of a health agency. Our institute is responsible not only for advancing scientific knowledge, but for doing so in a way that honors the dignity, individuality, and autonomy of the people affected by the health issues we address. For this reason, I am very proud to share the updated NIAID HIV Language Guide, a thoroughly vetted resource to inform our written and verbal communications.

NIAID has long been engaged in rich and multifaceted collaborations with HIV advocates and community stakeholders—partnerships that I prize and am honored to carry forward. Among their many contributions to HIV science, our community partners ensure that our language evolves as fluidly as our knowledge of the virus itself. Through their insights, the words we choose to describe the pathogen, its effects on the body, and the people who are affected by and living with HIV, have become increasingly person-centered. This progress reflects and upholds a commitment to avoid defining people by the disease with which they live. 

Despite this progress, the scientific community often lags in adopting evolving language, and many of the terms and phrases we use today are still insensitive and disrespectful to the people we aim to serve. Harmful language undermines people’s trust in biomedical research, and language-driven stigma prevents people from seeking health services which provide benefit. Non-inclusive language perpetuates knowledge gaps, limiting our ability to fully understand the people participating in research. As scientists and public health practitioners, we cannot be cavalier about language. Our words matter.

This guide originated as a resource for the HIV field, but respectful, inclusive, and person-first language is essential in all scientific communication. To that end, I am committed to following the NIAID HIV Language Guide in my communications, and strongly encourage all NIAID staff, funded research networks, sites, centers, investigators, and partners to do the same. We will not always get it right, but we will continue to try. We must support each other in learning, hold each other accountable, and continue to adapt as terms and norms change. 

For more information about the language guide and supporting resources, please visit https://www.niaid.nih.gov/research/hiv-language-guide. Spanish and Portuguese translations are coming soon.

An HIV drug that suppresses the activity of the CCR5 receptor—a collection of proteins on the surface of certain immune cells—was associated with better renal function in kidney transplant recipients with HIV compared to people who took a placebo in a randomized trial. Study participants taking the drug, called maraviroc, also experienced lower rates of transplant rejection than those taking placebo, but the difference was not statistically significant due to lower-than-expected rejection rates across the entire study population. The findings of the NIAID-sponsored trial were presented today at the 2024 American Transplant Congress in Philadelphia. 

The CCR5 receptor helps HIV enter CD4+ T cells. Some people have a genetic mutation that prevents the CCR5 receptor from working, and either cannot acquire HIV or experience slower HIV-related disease progression if living with the virus. It has separately been observed that people with the same CCR5 genetic mutation have better outcomes following kidney and liver transplantation. The CCR5 antagonist class of antiretroviral drugs was developed to mimic the naturally occurring CCR5 mutation and is a well tolerated component of HIV treatment, but the drugs have not been evaluated as an intervention to improve transplantation outcomes in people. Furthermore, transplant recipients with HIV more frequently experience transplant rejection and elevated CCR5 activity than transplant recipients without HIV.

A research team led by the University of California San Francisco conducted a U.S.-based Phase 2 trial to assess the safety and tolerability of the CCR5 antagonist maraviroc given daily from the time of transplant onward among kidney transplant recipients, and to compare renal function of people taking daily maraviroc to those taking a placebo one year (52 weeks) post-transplant. All study participants were living with HIV and were virally suppressed on antiretroviral therapy (ART) regimens. The study randomized 97 participants to receive maraviroc or a placebo in addition to their continued ART regimens post-transplant. Of them, only 27 participants were able to complete all necessary study examinations through 52 weeks due to logistical complications from the SARS-CoV-2 pandemic. At one-year post-transplant, the mean estimated glomerular filtration rate—a measure of how well kidneys were working—was significantly higher in participants receiving maraviroc in addition to their ART regimen compared with participants receiving ART and placebo (59.2 versus 49.3 mL/min/1.73m²). The drug was safe and well tolerated. 

Four of the 49 participants taking maraviroc and 6 of the 48 participants taking placebo experienced transplant rejection, but this difference was not statistically significant given the relatively small sample size. Transplant rejection rates were lower than expected across both study groups, which the study team suggests may be a favorable outcome of the ART regimens most participants were taking. 

The addition of maraviroc significantly improved renal function in kidney transplant recipients with HIV compared to placebo. According to the authors, these findings warrant further exploration of the benefit of CCR5 antagonists in all kidney transplant recipients regardless of HIV status.

For more information about this study, please visit ClinicalTrials.gov and use the identifier NCT02741323.

Reference:

Brown et al. Beneficial Impact of CCR5 Blockade in Kidney Transplant Recipients with HIV. American Transplant Congress in Philadelphia, Pennsylvania. Tuesday, June 4, 2024.