Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Emory and CDC scientists explore why most breastfed infants of HIV-positive mothers resist infection

26.11.2003


Although prolonged breastfeeding is well known to be a major route of transmission of HIV infection to infants and is estimated to cause one-third to one-half of new infant HIV-1 infections worldwide, the majority of breastfed infants with HIV-positive mothers remain uninfected, even after months of exposure.



Investigators at Emory University School of Medicine, the Centers for Disease Control and Prevention, the Emory Vaccine Center, and the University of Paris reviewed the scientific literature to pinpoint the reasons why many breastfed infants resist HIV, with the goal of devising future intervention strategies to prevent newborn infections. Their findings were published online in November and will be published in the December issue of The Lancet Infectious Diseases.

The researchers, led by Athena P. Kourtis, MD, PhD, MPH, formerly assistant professor of pediatrics at Emory University School of Medicine (now at Eastern Virginia Medical School and working at CDC) and Chris Ibegbu, PhD of the Emory Vaccine Center, identified several factors that have been cited by scientists as potentially enabling or preventing transmission of HIV through breastfeeding. Enabling factors could include the introduction of HIV into the gastrointestinal tract through a breach in the cell layer in the intestinal lining, or immune activation in the gastrointestinal tract could cause more HIV virus to reach this epithelial layer. Protective factors may include the hostile environment presented to viruses by the saliva and its various viral-inhibiting components.


The presence of HIV antibody in saliva already has been recognized in HIV-infected individuals, but scientists do not yet know whether this antibody is developed in non-infected breastfed infants, or whether it has a protective role against HIV. Natural killer (NK) cells or natural antibodies to HIV in exposed mucosal surfaces of infants could also play a role in resistance to HIV infection. Acquired T cell responses or specific antibody responses also may play a preventive role. Immune CD4 and CD8 T cells and antibodies in the mother’s milk have been studied as factors that could account for this protection.

"In the developing world, where alternatives exist, breastfeeding is not recommended for HIV-positive mothers, which in part explains our lack of knowledge about resistance to infection," Dr. Kourtis says. "In the developing world, however, breastfeeding often is the only practical option for feeding infants, which makes understanding the mechanisms of HIV transmission a research priority. Inconsistent research findings about the role of anti-HIV antibodies and HIV-specific T cell responses have left significant gaps in our understanding of HIV transmission through breastfeeding."

Dr. Kourtis believes that advances in laboratory methods will help scientists clarify which immune factors are most important in HIV protection and help in the development of carefully planned intervention strategies. These could possibly include giving antibodies to the mother in late pregnancy or to the newborn, together with antiretroviral prophylaxis, she explains. Some of these approaches will be tested soon in large international trials.

Other scientists involved in the study included CDC scientists Salvatore Butera, PhD and Ann Duerr, MD, PhD, MPH and Laurent Belec, MD, PhD, of the Institut de Recherces Biomedicales des Cordeliers, Universite Paris.

Tia Webster | EurekAlert!
Further information:
http://www.emory.edu/

More articles from Health and Medicine:

nachricht Investigators may unlock mystery of how staph cells dodge the body's immune system
22.09.2017 | Cedars-Sinai Medical Center

nachricht Monitoring the heart's mitochondria to predict cardiac arrest?
21.09.2017 | Boston Children's Hospital

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>