Going Bananas to Prevent HIV

By Nick Gubitosi

Two weeks ago (March 19, 2010), scientists from the University of Michigan published a study about an ingredient known as BanLec which is derived from bananas and acts as a potent inhibitor of the HIV virus.  What stands out about BanLec is that it is a cheaper form of therapy that may provide a wider range of protection when compared to current anti-retrovirals which are commonly synthetic and made ineffective after small mutations to the virus.  The cost and effectiveness of BanLec make it a promising candidate for the future prevention of HIV and AIDS, giving it the potential to save millions of lives.

BanLec is a type of lectin found in bananas that can identify foreign invaders such as a virus and attach to it.  A lectin is a naturally occurring chemical in plants that is of great interest to scientists because of its ability to halt the chain of reaction that leads to a variety of infections.  The researchers in this study discovered that BanLec inhibits HIV infection by binding to the virus’s protein envelope, therefore blocking it from entering the body.

According to Michael D. Swanson, the lead author of the study, “The problem with some HIV drugs is that the virus can mutate and become resistant, but that is much harder to do in the presence of lectins.”  He goes on to explain that the lectins work by binding to sugars found all over the envelope of the HIV virus, and because of this the virus would have to go through multiple mutations for the lectin to stop working.  This makes drugs such as BanLec more effective than some current anti-retrovirals which could become ineffective after one mutation to the virus.

So far all tests have been conducted in the laboratory, but Swanson is currently working on making BanLec suitable for human patients.  Its clinical use is still considered to be far away but researchers believe it could ultimately be used as a self applied microbicide for the prevention of HIV infection.

While BanLec is no cure to AIDS, the information gained from this study is very exciting because according to researchers, millions of lives could be saved over the course of a few years with just a moderately successful treatment.

Click here for source

An uncommon use for a common drug offers hope to millions of HIV-positive patients

By Liz H. ‘10

Microscopic view of HIV (green) emerging from an infected T-cell. CDC

A promising new HIV treatment has been discovered in an unlikely source:  a widely available acne medication developed in the 1970s.  A team of scientists from Johns Hopkins University reports that minocyclin stops HIV-infected human cells from reactivating and replicating, in a study published in the April 15th issue of the Journal of Infectious Diseases.  Their findings may lead to an improved and more effective treatment regimen for HIV infection.

The researchers focused their study on latent, non-replicating HIV-infected human T-cells.  T-cells are a type white blood cell that normally fights infection.  HIV infects T-cells and can “rest” inside of them for an extended period of time.  The virus does not harm the T-cell during this latent phase, but can eventually “wake-up” and re-activate the T-cell, which spreads HIV infection and weakens the immune system.

In this study, the scientists treated latent HIV-infected human T-cells with minocycline and measured the level of re-activated T-cells over time.  They also performed the same measurements on cells that were not treated with minocycline.  The researchers found that the minocycline-treated cells did not display detectable levels of reactivation while the untreated cells displayed elevated levels.

Upon closer analysis of the activity of minocycline inside of cells, the scientists discovered that the drug interferes with important cellular communication pathways that cause the T-cell to activate and spread HIV to other cells.  “It prevents the virus from escaping in the one in a million cells in which it lays dormant in a person…That’s the goal:  Sustaining a latent non-infectious state,” explains Gregory Szeto, a Hopkins graduate student who worked on the project.

These findings suggest that minocycline could be used in conjunction with HAART, the current HIV treatment standard, to keep the virus dormant inside of T-cells.  “While HAART is really effective in keeping down active replication, minocycline is another arm of defense against the virus,” says author Janice Clements.  Minocycline is an attractive addition to the current arsenal of HIV medications because it is relatively inexpensive, does not inhibit the ability of T-cells to fight other infections, and is not likely to cause viral drug resistance.

Current treatment for HIV/AIDS involves a combination therapy approach known as HAART.  Patients on HAART take at least 3 antiretroviral drugs daily that act on the virus in different ways to reduce its levels in the bloodstream.  Although HAART can extend the life of an infected individual, it is not a cure and causes unpleasant side effects and the development of drug resistance.  For the 40 million HIV-positive individuals worldwide, this new use for minocycline promises improved outcomes.

Want more information?

What is HIV?

Press Release

Bullet shaped virus may be the future of new cancer and HIV treatments

By Liz Humes

An obscure virus that does not harm human cells has been generating a wave of excitement in the scientific community.  So what is the big deal?  A team of researchers from UCLA has reported the 3D structure of the vesicular stomatitis virus (VSV) in a break-through study published in the February 5th edition of Science (full article).  Their findings may shed light on how VSV can be manipulated and used in the treatment of cancer and in the development of vaccines for HIV and other harmful viruses.

The researchers used advanced, cutting-edge imaging techniques to visualize the 3D structure of VSV, which appears to have a bullet shaped head and cylindrical trunk.  They also characterized how the virus comes to form this bullet shape.  With this additional level of understanding of the physical structure of the virus, scientists believe that they can find ways to modify the structure of the virus and use it to treat and prevent illnesses such as cancer and AIDS.

As author Z. Hong Zhou remarked, “This work moves our understanding of the biology of this large and medically important class of viruses ahead in a dramatic way.”

VSV is a model virus that scientists use in the laboratory to study dangerous viruses that cause illnesses such as the flu, measles, and rabies.  Previous studies have shown that VSV can detect and kill human cancer cells.  Other studies have addressed the question of how to manipulate the virus to deliver a vaccine against HIV to the human body.

3D animation of VSV trunk

(Video is a 3D animation of the lower trunk structure of VSV-source)

A closer look at vaccine technology

A current trend in vaccine development is to use harmless viruses as “vectors” that can carry a specific vaccine to human cells.  These viruses have been engineered in the laboratory to carry pieces of genetic material from other pathogens and when they attach to human cells, they inject this genetic material into the cells.  These actions mirror an infection by the pathogen itself, although the virus vector does not actually cause an infection, and stimulates an immune response.  The human body then remembers how to respond to this pathogen the next time it encounters the pathogen and the body is protected from infection.

Modified versions of the viruses that cause the common cold and small pox are being studied in addition to VSV for use as vaccine vectors.  Given the potential that this type of vaccination has to prevent deadly infections from viruses and bacteria, this is an area of research one should surely keep an eye on.

Want more information?

Press release

Vaccination information

HIV vaccination development

Newly discovered antiviral fights HIV, Ebola and other deadly viruses

By Nick Gubitosi            February 4, 2010

A picture of the HIV virus attacking a lymphocyte

A group of researchers lead by scientists from UCLA have identified a “broad spectrum” antiviral small molecule which targets the many envelope encased deadly viruses that exist today.  This antiviral would fight enveloped viruses such as HIV, Ebola, and influenza, as well as viruses that haven’t even been discovered yet.

Dr. Benhur Lee, an associate professor at UCLA, was working with colleagues on 23 various pathogens when they discovered that this antiviral molecule, known as LJ001, only interfered with enveloped viruses through a mechanism which is still not fully understood.

This LJ001 molecule binds to both healthy and viral cells within the body, but only causes harm to the viral cells.  Unlike the healthy cells in your body, viral cells lack the ability to repair themselves because they are not metabolically active.  Therefore the damage done to the viral cells is permanent, while it is completely harmless to the healthy body cells.

Broad spectrum antivirals are hard to find, and usually accompanied with many shortcomings.  One such antiviral, Ribavirin, targets RNA replication and is only effective against a few viruses, is too expensive for widespread use, and produces unwanted side effects.  LJ001 targets viral structure, does not appear to be toxic, and can attack a large group of viruses, making LJ001 the first antiviral of its kind.

Viruses can differ from one another and even mutate as seen with HIV, making them extremely hard to fight off.  Using an antiviral such as LJ001, which safely targets a feature common to an entire class of viruses, may be the potential answer to this problem.

See here for Press Release

Structure of key HIV protein solved, offers hope to millions of HIV/AIDS patients

Views of the integrase enzyme bound to viral DNA and to the integrase inhibitors MK0518 and GS9137 (b and c).

By Liz H.

After nearly 4 years and 40,000 trials, a team of researchers from Harvard University and Imperial College London has reported the structure of the HIV enzyme integrase in a landmark study published in the January 31st issue of Nature (full article).  Integrase is a key retroviral enzyme that allows the virus to insert its DNA into the chromosomes of host cells and replicate. This discovery sheds light on how current integrase inhibitors target the enzyme and may lead to the development of more effective therapeutics.

Scientists grew a crystal of the enzyme obtained from the Prototype Foamy Virus, a model for HIV, and used a synchotron machine at the Diamond Light Source in South Oxfordshire to take a picture of the enzyme’s structure using a method known as x-ray diffraction.  These crystals were then soaked in integrase inhibitors and the drugs’ actions were also studied using x-ray diffraction.  Scientists hope that their findings will allow them to develop improved next-generation integrase inhibitors.

Over 33 million people are infected by HIV and combination antiretroviral therapy (ART) is used to slow the progression of disease (source). However, the increasing prevalence of multi-drug resistance, high cost, and side effects of therapeutics undermines the efficacy of current treatments.