A Duke University research team published study results on Monday that revealed the immune system of a patient with both lupus and HIV made neutralizing antibodies, which is essential for an effective vaccine response.
The patient has systemic lupus erythematosus, which causes the immune system to attack the body. The study, published in the Journal of Clinical Investigation, said few people develop antibodies against HIV.
"Over the years we have searched for and now have found one person with SLE who was also chronically infected with HIV to determine if this person could make broad neutralizing antibodies," Barton Haynes, the director of the Duke Human Vaccine Institute and senior author of the study, said. "We found that the patient did indeed make these important antibodies, and by determining how this immune response occurred, we have enhanced our understanding of the process involved."
Haynes said he discovered that some broad neutralizing antibodies cross-reacted with tissues. These autoreactive antibodies were kept under control by immune tolerance controls that sense antibodies and prevent them from reproducing.
Haynes' theory was the immune system labeled the antibodies as harmful and worked to eliminate them, providing an escape mechanism for the disease. The research team theorized that when the body's immune system is compromised with an autoimmune disease, immune tolerance controls are defective and broad neutralizing antibodies are reproduced.
"The cross-reactivity of the broad neutralizing antibody with dsDNA was very surprising and provided support for the hypothesis that broad neutralizing antibodies are similar to the autoantibodies that arise in lupus patients who are not infected with HIV," Duke Assistant Professor of Medicine Mattia Bonsignori said.
Bonsignori said that patients with lupus are not immune to HIV and still should avoid contracting the disease.
"Our study of this person with SLE and HIV has been critically instrumental in our understanding of the unusual biology of the remarkable host control of antibody responses to the conserved broad neutralizing sites of the HIV envelope," Bonsignori said. "We are hopeful that these insights in lupus will aid in our implementation of strategies for designing experimental vaccines capable of overcoming the host tolerance control of broad neutralizing antibodies."