For years, many scientists have heralded vaccines as the only real and effective way of preventing the spread of Human Immunodeficiency Virus (HIV). However, the nature of the virus and the number of varying strains have meant that said vaccines have remained elusive to the medical community ever since its spread almost half a century ago.
Specialists in the field have been looking to find a way for the immune system to produce what is known as a ‘broadly neutralizing antibody response,’ which was believed to be efficient and effective against the multiple strains of HIV.
They act by essentially inhibiting or neutralizing any biological effects a pathogen may have, such as how a virus enters cells. This is a set farther than other antibodies, which usually stick to antigens on the cell surface of a pathogen and ‘label’ it as foreign in order for the various types of white blood cells to dispose of.
Importantly, these types of antibodies are more than capable of protecting humans from viruses that enter immune system cells, like HIV, as they can neutralize the cells without the aid of white blood cells.
Indeed, in some cases, people living with HIV do begin producing these antibodies, however this process can take a minimum of two years.
Rewind the clocks by ten years and an important discovery was made: some broadly neutralizing antibodies for HIV are auto-reactive, and begin neutralizing healthy tissue. However, the body senses and protects from these antibodies, halting their production.
Professor Barton F. Haynes, who works at the Duke Human Vaccine Institute in the Duke University Medical Centre in Durham, was the one who made the discovery. He believed that seeing as these antibodies remain under the control of the immune system, and are seldom produced, HIV is able to hide under the radar under the alias of healthy body cells.
However, the team from Duke University hypothesized that should the body relegate control of its antibodies, as in an autoimmune condition such as lupus, the powerful broadly neutralizing antibodies would once again be available.
Thus, when a patient with the excessively rare combination of systemic lupus erythematosus, or SLE, and HIV was diagnosed, it was believed that the individual would be able to more readily make the antibodies required to neutralize the virus.
The research team published the study in the Journal of Clinical Investigations.
In their study, a patient had been diagnosed with a strain known as HIV-1 fourteen years ago, and subsequently developed SLE in the last six.
They discovered that a type of antibody known as CH98 was indeed able to neutralize the HIV-1 strain that the patient had, attaching to the CD4 binding site on the HIV-1 glycoprotein 120, a structure found on the envelope of the virus.
The team was keen to mention that people with lupus are still able to contract the virus and that adequate protection, such as contraceptive measures, is still required. What the study did show was that patients with the autoimmune condition could produce the required antibodies should they contract the virus, however this would take time, and by which point HIV would have developed.
This study was highly significant, however, showing the biology of the immune response in SLE and HIV patients, as well as showing that the desired antibodies are indeed created in what is thought to be an effective way of responding to the HIV virus.
By looking at the immune response of this unique patient, the team aims to produce trial vaccines for the virus that work by altering the way the immune system keeps broadly neutralizing antibodies in check, and thus allowing their production.
What other conditions have you heard of that could prove to be effective in the elimination of HIV?