Protein Prevents HIV Infection

Information about penis enlargement,
penis size, STDs, sexuality,
penis conditions, jelqing,
infertility, adolescence
and prostate health.
Erectile Dysfunction  |  Fertility  |  Penis Conditions  |  Penis Enlargement  |  Penis Size  |  Prostate  |  Sexuality  |  STDs


12 January 2001
Protein Prevents HIV Infection

In a promising advance in the war against AIDS, scientists have designed a potent, new protein that can prevent HIV infection by blocking its entry into human cells. The protein, called 5-Helix and designed to bind to a region in the HIV coat protein gp41, is able to prevent a wide range of HIV strains from fusing to the cell membrane and thereby infecting it.

The researchers say that the 5-Helix protein could therefore serve as the basis for a new class of broad spectrum, injectible drugs against HIV, one that could be used as an alternative when current drugs fail, i.e., as a salvage therapy. Drugs based on 5-Helix would need to be injected, but could be self-administered much the same way as injectible drugs such as insulin or erythropoeitin are.

The 5-Helix protein could also serve as a basis for prophylactics that could be injected immediately after inadvertent needle pricks in hospital settings to prevent HIV from infecting cells.

These results, from Peter S. Kim and colleagues at the Whitehead Institute for Biomedical Research and the Howard Hughes Medical Institute and published in the January 11 issue of ScienceExpress (an electronic publication of Science magazine highlighting papers from future issues), hold great promise for clinical applications.

Unlike currently used drugs that target HIV at other points during its life cycle—after it has already infected the cell—drugs based on 5-Helix could work by preventing HIV fusion with cell membranes. Such "entry inhibitors" represent a promising and alternative line of attack against HIV. In fact, one entry inhibitor, called T-20, has shown promise in Phase II clinical trials when injected into patients, but it has to be injected in large quantities.

The 5-Helix protein is a potent, broad-spectrum inhibitor of HIV infection that targets a different part of the HIV coat protein than T-20. The researchers are particularly excited by the results they see in the 5-Helix protein. "We may only be a few steps away from seeing whether 5-Helix works in monkeys," says Kim.

This report is the culmination of decades long research into the structure of the HIV coat protein, called gp41. Two years ago, Dr. Kim's lab at the Whitehead Institute used x-ray crystallography to decipher the architecture of gp41. This protein plays a key role in allowing the virus membrane to fuse with the membrane of the cell it is attacking. Scientists have long targeted gp41, hoping that a drug aimed at this protein could nip HIV infection in the bud by blocking the virus' ability to enter cells.

In its inactive form, gp41 lies just beneath the surface of the virus coat, but as HIV prepares to enter a cell, gp41 undergoes a remarkable change. A dormant protein region called the "fusion peptide" is propelled, harpoon-like, toward the host cell membrane, hooking the target for infection. For a fleeting moment, the exposed gp41 is an Achilles' heel for the virus—vulnerable to counterattack by drugs.

The Kim lab designed 5-Helix to bind specifically and tightly to a portion of gp41. Even at nanomolar concentrations, the 5-Helix was able to prevent HIV from entering cells. 5-Helix also has other qualities that make an attractive drug candidate. It is very stable, so it is less likely to be degraded by the body's enzymes; can be made larger to avoid elimination by the kidneys; and modified such that it can escape the body's immune response.

The 5-Helix strategy may have broader application to a wide range of human viruses. Like HIV, many different viruses, including Ebola, HRSV (human respiratory syncytial virus, a leading cause of infant mortality in developed countries), and the flu virus, use a similar fusion membrane strategy to enter cells. The 5-Helix protein can be used as a model to design similar inhibitors against HRSV, for instance.

The 5-Helix results also suggest a new strategy for generating antibodies against HIV, which may be useful in vaccine development.


Home Page
Back to the home page for penis news and info.

Penis Size Survey
How big is the average penis? Measure the size of your penis and see how you compare in our penis size survey.

Reference Guides

Adolescence

Diseases

Dysfunction

Fertility

Male Menopause

Male Sexuality

Penis Conditions

Penis Enlargement

Penis Size

Prostate Health

Penis Enlargement

Enlargement FAQ

Jelqing

Penis Surgery

Penis Pills

Enlargement Sites

Traction

Penis Ponderings
Our resident columnist takes a light-hearted look at various knob related matters.

Penis Links
A variety of penis health related links including the FDA, AMA, vasectomy info, foreskin restoration, STD information, penis pictures, male sexual health, erectile dysfunction and more.

Penis Provisions
Condoms, lubricants, HIV testing kits, jock straps, sports underwear, penis pumps, supplements, pheromones, exercises to increase length and girth, sexual health books, personals, seduction guides, ejaculatory boosters, hair removal products - everything you need for a happy, contented penis!

Contact Us
Please be aware that we can't respond to health related questions via email. Please see your doctor for health matters.

Erectile Dysfunction  |  Fertility  |  Penis Conditions  |  Penis Enlargement  |  Penis Size  |  Prostate  |  Sexuality  |  STDs
Home  |  Penis Size Survey  |  Penis Enlargement FAQ  |  Penis Provisions  |  Penis Links  |  Penis Ponderings  |  Contact
 
Copyright 2000 - 2006 altPenis.com and its licensors. All rights reserved.

    

Please be aware that we cannot respond to your health related questions via email.
Please see your doctor for any concerns about your reproductive health that you may have.
The information presented on altPenis.com is for general convenience and entertainment only and is not a substitute for medical advice. Your use of the altPenis.com website indicates your agreement to our terms and conditions of use. Links from this site to other sites do not constitute endorsement of those sites and we take no responsibility for the content of external sites.