Scientists have captured an image of the elusive protein that HIV utilizes to spread infection among cells.

HIV is capable of escaping from responses sent out by the human body's immune system because the protein that HIV uses to spread infection is in a constant state of change. This makes it difficult for the human body to set up its defenses against the attack of the virus.

However, a team of scientists have finally captured a high-resolution image of the surface spike protein, finally being able to remove the disguise that the protein has been using.

The method on how the protein is constantly changing shape is currently being monitored by the scientists, as data on the protein's characteristics will potentially lead to new methods through which HIV can be addressed through vaccines and drugs.

The research was published online in two separate papers on Oct. 8, in the journals Nature and Science. 

The team of scientists include Walther Mothes from Yale University, Scott Blanchard from Weill Cornell Medical College and Peter Kwong from the Vaccine Research Center of the National Institute of Allergy and Infectious Diseases.

In the papers, the team describes the dynamics and structure of the protein as it is used by HIV to combine with and invade healthy cells.

"Now we can see how this fusion machine works, and in a general way it is similar to how fusion works in influenza and Ebola," said Mothes, who is in Yale University an associate professor of microbial pathogenesis.

The scientists have determined that the protein is required to be in its "open state" for it to combine with and invade healthy cells. In the protein's "closed state," the visibility of the protein to antibodies becomes limited. This is the reason why the protein spends more time in its closed state.

The protein only goes into its open state when it is about to attack a healthy cell. During this open state, the protein becomes visible to antibodies and susceptible to being eliminated.

Mothes added that new studies explain why a series of antibodies that have been discovered in patients with AIDS are capable of protecting the human body from the spread of the disease. These antibodies are capable of keeping the spike protein in its closed state, which would render it unable to infect healthy cells.

According to Mothes, being able to determine the structure of the spike protein while it is in its closed state and visualize the fast openings presented by the protein when it attacks will be a major development in the creation of designs for vaccines and drugs for the treatment of HIV.