A primary immunodeficiency (PI), or primary immune deficiency disease, is an inherited immune system disorder caused by gene mutations which prevent the immune system from functioning properly. It can be difficult to diagnose a primary immunodeficiency; over 485 different immunodeficiencies, also referred to as in-born errors of immunity (IEI), exist. IEIs may lead to increased susceptibility to infections, autoimmune or autoinflammatory issues, allergies, or even increased oncological risks. Identifying the underlying genetic causes of primary immunodeficiencies, and performing research into them, could help with treatment, care, and avoiding disease progression and death.
According to News Medical, an international consortium co-led by Dr. Rubén Martínez-Barricarte, PhD discovered a novel primary immunodeficiency. In the findings, published in Science Immunology, the researcher team found that a multimorphic IRF4 mutation caused serious susceptibility to opportunistic infections, as well as other immune issues. Normally, this gene encodes for the production of the IRF4 protein; this protein plays a role in immune cell function.
About five years ago, Dr. Martínez-Barricarte linked IRF4 mutations to Whipple’s disease, a rare bacterial infection that impacts the joints and gastrointestinal system. Two years later, Dr. Martínez-Barricarte began collaborating with other doctors to treat a young male who often faced serious and sometimes life-threatening infections. These infections spanned fungal, viral, and even bacterial infections. After sequencing part of the boy’s genome, researchers found a spontaneously-occurring IRF4 mutation. The IRF4 Consortium was founded after Dr. Martínez-Barricarte and his team reached out for assistance to others studying this mutation. So far, seven people worldwide with this particular mutation have been identified. The mutations impair B- and T-cell function.
While more research is needed, this discovery could help provide diagnoses to those in need.
Primary Immunodeficiency (PI): The Important Details
As described above, a primary immunodeficiency causes poor immune function; those with PIs cannot fight infections effectively. While some PIs are inherited, others – such as the one resulting from IRF4 – occur de novo (spontaneously). Types of primary immunodeficiencies include common variable immunodeficiency disease (CVID), severe combined immunodeficiency disease (SCID), and chronic granulomatous disease (CGD). Symptoms differ between primary immunodeficiency subtypes. However, with any primary immunodeficiency disease, patients are susceptible to different infections. Treatment options vary. These treatments may be used to manage infections, strengthen the immune system, provide immunoglobulins, or address the underlying cause. There are no cures for primary immunodeficiencies.