Health Australia (Commonwealth Union) – Malaria is a mosquito-borne infectious disease that affects millions of people worldwide, especially in tropical regions. The disease is caused by Plasmodium parasites, which are transmitted to humans through the bite of infected female Anopheles mosquitoes. Malaria can lead to severe illness and even death if not treated promptly and correctly. Anopheles mosquitoes belong to the Culicidae family, which consists of over 400 different species.
The connection between Anopheles mosquitoes and the transmission of malaria was first established in the late 19th century by a series of groundbreaking discoveries. In 1880, Charles Louis Alphonse Laveran, a French physician, observed parasites within the blood of a patient suffering from malaria. This observation led to the discovery of Plasmodium; the protozoan parasite responsible for causing malaria.
The onset of malaria symptoms typically occurs within 7 to 30 days after being bitten by an infected mosquito. Early symptoms can be mistaken for the flu or other common illnesses, making it crucial for individuals at risk of malaria to seek medical attention if they experience any of the symptoms that include high fever, shaking chills, headache, muscle aches, fatigue, nausea and vomiting.
Researchers at The Australian National University (ANU) have unearthed a previously undiscovered function of a subset of immune cells called Atypical B cells (ABCs), demonstrating their capacity to combat infectious diseases like malaria.
The researchers point out that these findings suggest that ABCs could hold the key to novel treatments for chronic autoimmune conditions such as lupus. This breakthrough sheds light on the immune system’s mechanisms in combating infections and brings scientists closer to leveraging the body’s innate defenses against malaria.
The research indicates a strong association between ABCs and malaria, as individuals with malaria tend to have higher levels of these cells compared to the general population.
Lead author Dr. Xin (Andy) Gao, from the ANU Division of Immunology and Infectious Diseases, indicated that their study aimed to delve into the mechanisms driving the emergence of ABCs in the immune system, while also assessing their efficacy in combating infections.
Dr. Gao further pointed out that while ABCs were once primarily associated with chronic inflammatory diseases and autoimmunity, their recent discovery unveils a previously unrecognized facet of these cells: their capacity to combat diseases. This dual role renders ABCs akin to a double-edged sword.
He pointed out that contrary to previous assumptions, ABCs are not mere bystander cells; their significance surpasses their prior understanding.
Dr. Gao also stated that their investigation reveals that ABCs play a pivotal role in the development of T follicular helper cells. These specialized cells are instrumental in producing potent antibodies crucial for combating malaria parasites.
He indicated that these antibodies serve to obstruct parasites within the bloodstream as they journey from the initial mosquito bite site to the liver, where the infection takes hold.
Researchers of the study pointed out that in 2022, malaria claimed over 600,000 lives globally. Despite being preventable and curable, the fight against this disease is complicated by the resilience of malaria parasites, which continue to develop resistance to existing treatments. Researchers at ANU discovered that a gene called Zeb2 plays a critical role in the production of ABCs in mice, shedding light on potential new therapies.
“We found that manipulating the Zeb2 gene disrupted the creation of ABCs in the immune system,” The co-author of the study, Professor Ian Cockburn, who is from ANU, as well explained.
“Importantly, we found that mice without the Zeb2 gene were unable to control malaria infection.
“Therefore, the findings show that ABCs play a crucial role in fighting malaria infections.”
The researchers also point out that focusing on ABCs may also bring about the path for new treatments for autoimmune diseases that include lupus.
“ABCs also appear in large numbers in many autoimmune diseases, including lupus, which can be life-threating in severe cases,” added Professor Cockburn.
“By developing a better understanding of the role of ABCs in the immune system and the cells’ role in fighting disease, it could bring us a step closer to one day developing new and more effective therapies.”
The publication is featured in Science Immunology. The ANU’s Division of Immunology and Infectious Diseases is leading the charge in groundbreaking scientific advancements against malaria.
With the difficulties many past researchers had in finding new treatments, the discovery of ABCs is likely to provide a much better understanding of the mechanism adopted by malaria during infections.
