PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Breast milk protein may be key to protecting babies from HIV infection

2013-10-22
(Press-News.org) Contact information: Sarah Avery
sarah.avery@duke.edu
919-660-1306
Duke University Medical Center
Breast milk protein may be key to protecting babies from HIV infection

DURHAM, N.C. – A substance in breast milk that neutralizes HIV and may protect babies from acquiring HIV from their infected mothers has been identified for the first time by researchers at Duke Medicine.

The protein, called Tenascin-C or TNC, had previously been recognized as playing a role in wound healing, but had not been known to have antimicrobial properties. The discovery could lead to potential new HIV-prevention strategies.

Reporting in the journal Proceedings of the National Academy of Sciences during the week of Oct. 21, 2013, the researchers describe how the TNC protein in breast milk binds to and neutralizes the HIV virus, potentially protecting exposed infants who might otherwise become infected from repeated exposures to the virus.

"Even though we have antiretroviral drugs that can work to prevent mother-to-child transmission, not every pregnant woman is being tested for HIV, and less than 60 percent are receiving the prevention drugs, particularly in countries with few resources," said senior author Sallie Permar, M.D., Ph.D., assistant professor of pediatrics, immunology and molecular genetics and microbiology at Duke. "So there is still a need for alternative strategies to prevent mother-to-child transmission, which is why this work is important."

Worldwide in 2011, an estimated 330,000 children acquired HIV from their mothers during pregnancy or birth, or through breastfeeding according to UNICEF. As international health organizations have set a goal of eliminating mother-to-child infections, researchers have worked to develop safe and affordable alternatives to antiretroviral therapy that can be used to block HIV transmission to infants.

Permar and colleagues focused on breast milk, which has long been recognized as having some protective quality that inhibits mother-to-child transmission despite multiple daily exposures over months and even years of nursing. Earlier studies had identified some antiviral properties in breast milk, but the majority of the HIV-neutralizing activity of breast milk remained unexplained. More recent studies pointed to a large protein that had yet to be identified.

In their study, the Duke team screened mature milk samples from uninfected women for neutralizing activity against a panel of HIV strains, confirming that all of the detectable HIV-neutralization activity was contained in the high molecular weight portion. Using a multi-step protein separation process, the researchers narrowed the detectable HIV-neutralization activity to a single protein, and identified it as TNC.

"TNC is a component of the extracellular matrix that is integral to how tissues hold themselves together," Permar said, noting that co-author Harold Erickson, Ph.D., professor of cell biology at Duke, was among the first to identify and describe TNC in the 1980s. "This is a protein involved during wound healing, playing a role in tissue repair. It is also known to be important in fetal development, but its reason for being a component of breast milk or its antiviral properties had never been described."

Further analysis described how TNC works against HIV by blocking virus entry. The protein is uniquely effective in capturing virus particles and neutralizes the virus, specifically binding to the HIV envelope. These properties provide widespread protection against infection.

"It's likely that TNC is acting in concert with other anti-HIV factors in breast milk, and further research should explore this," Permar said. "But given TNC's broad-spectrum HIV-1-binding and neutralizing activity, it could be developed as an HIV-prevention therapy, given orally to infants prior to breastfeeding, similar to the way oral rehydration salts are routinely administered to infants in developing regions."

Permar said TNC would also appear to be inherently safe, since it is a naturally occurring component of breast milk, and it may avoid the problem of HIV resistance to antiretroviral regimens that complicate maternal/infant applications.

"The discovery of the HIV inhibiting effect of this common protein in breast milk provides a potential explanation for why nursing infants born to HIV-infected mothers do not become infected more often than they do," said Barton F. Haynes, M.D., director of the Duke Human Vaccine Institute. "It also provides support for inducing inhibitory factors in breast milk that might be even more protective, such as antibodies, that would completely protect babies from HIV infection in this setting."



INFORMATION:



In addition to Permar, co-senior author was S. Munir Alam. Other authors include Genevieve G. Fouda, Frederick H. Jaeger, Joshua D. Amos, Carrie Ho, Erika L. Kunz, Kara Anasti, Lisa W. Stamper, Brooke E. Liebl; Kimberly H. Barbas, Tomoo Ohashi, M. Arthur Moseley, Hua-Xin Liao and Harold P. Erickson.

The study was funded by the Doris Duke Charitable Foundation Clinical Scientist Development Award; Duke University School of Medicine; Center for HIV/AIDS Vaccine Immunology; and the National Institute of Allergic and Immunologic Diseases (U19 AI067854) (K08AI087992) (CA047056).



ELSE PRESS RELEASES FROM THIS DATE:

Moderate to vigorous exercise boosts teens' academic performance

2013-10-22
Moderate to vigorous exercise boosts teens' academic performance Improvements over long term; particularly noticeable for girls' science results Regular moderate to vigorous exercise improves teens' academic performance, and particularly seems to help girls ...

Use of booze and drugs common among truck drivers on the road

2013-10-22
Use of booze and drugs common among truck drivers on the road Prevalence varies widely, but mainly linked to poor working conditions The use of booze and drugs among truck drivers on the road is common, but seems to be mainly linked to poor working conditions, ...

Study: No known hominin is ancestor of Neanderthals and modern humans

2013-10-22
Study: No known hominin is ancestor of Neanderthals and modern humans The search for a common ancestor linking modern humans with the Neanderthals who lived in Europe thousands of years ago has been a compelling subject for research. But a new study suggests the quest ...

Bottle feeding associated with increased risk of stomach obstruction in infants

2013-10-22
Bottle feeding associated with increased risk of stomach obstruction in infants Bottle feeding appears to increase the risk infants will develop hypertrophic pyloric stenosis (HPS), a form of stomach obstruction, and that risk seems to be magnified when mothers are older ...

Patients report doctors not telling them of overdiagnosis risk in screenings

2013-10-22
Patients report doctors not telling them of overdiagnosis risk in screenings A survey finds that most patients are not being told about the possibility of overdiagnosis and overtreatment as a result of cancer screenings, according to report in a research letter ...

Harvard researchers, pharma experts offer recommendations to expand access to clinical trial data

2013-10-22
Harvard researchers, pharma experts offer recommendations to expand access to clinical trial data Boston, MA – A new report by researchers from Harvard University and others in a working group convened by the Multi-Regional Clinical Trials Center (MRCT) ...

Less sleep associated with brain imaging findings of Alzheimer disease in elderly

2013-10-22
Less sleep associated with brain imaging findings of Alzheimer disease in elderly Getting less sleep and poor sleep quality are associated with abnormal brain imaging findings suggesting Alzheimer disease (AD) in older adults, according to a report published ...

Risk of Amazon rainforest dieback is higher than IPCC projects

2013-10-22
Risk of Amazon rainforest dieback is higher than IPCC projects A new study suggests the southern portion of the Amazon rainforest is at a much higher risk of dieback due to stronger seasonal drying than projections made by the climate models used in the ...

Stanford researchers demonstrate efficient method for converting fat cells to liver cells

2013-10-22
Stanford researchers demonstrate efficient method for converting fat cells to liver cells STANFORD, Calif. — In a feat of modern-day alchemy with huge potential for regenerative medicine, Stanford University School of Medicine scientists have developed ...

A natural boost for MRI scans

2013-10-22
A natural boost for MRI scans Magnetic resonance imaging (MRI) is a technique widely used in medicine to create images of internal organs such as the heart, the lungs, the liver and even the brain. Since its invention in 1977, MRI has become ...

LAST 30 PRESS RELEASES:

Five minutes exposure to junk food marketing results in children consuming 130 kcals more per day, regardless of media advertising type

Key brain areas are larger in teenagers with abdominal obesity

3-month program of time-restricted eating at any time of the day supports long-term weight loss in adults with overweight or obesity

GLP-1 RA medications safe and effective for treating obesity in adults with mental illness

New study discovers link between delayed puberty and early-onset type 2 diabetes for the first time

Scientists create ‘mini-ovaries’ that may shed light on sex determination and infertility

CrystalTac: vision-based tactile sensor family fabricated via rapid monolithic manufacturing

Soft robots with Cy5: an “intake and work” imaging technique for intraoperative navigation of gastric lesion

The greater a woman’s BMI in early pregnancy, the more likely her child is to develop overweight or obesity, Australian study finds

The combination of significant weight gain and late motherhood greatly increases a woman’s risk of breast cancer, UK study finds

Weight-loss drugs cut alcohol intake by almost two-thirds, research in Ireland suggests

Swedish study explores differences in how the sexes break down fat

Antibiotics taken during infancy linked to early puberty in girls

Real-world evidence links long-term use of oral and inhaled steroids to adrenal insufficiency

Phthalates may impact key genital measurement in 3-year-olds

Phosphate levels in blood strongly affect sperm quality in men

Testosterone during pregnancy linked to physical activity and muscle strength in children

Menopause at an earlier age increases risk of fatty liver disease and metabolic disorders

Early-life growth proved important for height in puberty and adulthood

Women with infertility history at greater risk of cardiovascular disease after assisted conception

UO researcher develops new tool that could aid drug development

Call for abstracts: GSA Connects 2025 invites geoscientists to share groundbreaking research

The skinny on fat, ascites and anti-tumor immunity

New film series 'The Deadly Five' highlights global animal infectious diseases

Four organizations receive funds to combat food insecurity

Ultrasound unlocks a safer, greener way to make hydrogels 

Antibiotics from human use are contaminating rivers worldwide, study shows

A more realistic look at DNA in action

Skia: Shedding light on shadow branches

Fat-rich fluid fuels immune failure in ovarian cancer

[Press-News.org] Breast milk protein may be key to protecting babies from HIV infection