A recent research study on the Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) has delved into the role of molecules known as ‘transcription factors.’ These molecules are responsible for the differentiation of immune system cells, and the study concludes that three of these molecules are expressed more intensely in the more virulent strains of the pathogen.
The PRRSV is recognized as one of the most dangerous pathogens in the swine industry. Beyond affecting the reproductive system in breeding sows and the respiratory tract in young animals, it is often associated with secondary diseases, making it the primary cause of economic losses in the global pork industry.
Conducted by the Animal Pathological Anatomy group at the University of Córdoba, led by researcher Librado Carrasco, the study has successfully identified the role of three key molecules in the immune defense against this pathogen in three target organs of pigs: the lungs, thymus, and tracheobronchial lymph node. These organs play a fundamental role in triggering the immune response and are the primary sites where the virus replicates upon entering the organism.
The research analyzed these organs in 70 pigs divided into three groups: one not infected as a control group, and two infected with different virulent strains of the virus. Specifically focusing on ‘transcription factors,’ molecules that regulate the differentiation of cells involved in the immune system.
According to Inés Ruedas-Torres, one of the study’s lead authors, the results indicate that three of these molecules (T-BET, FOXP3, and EOMES) are expressed more intensely and at an earlier stage in the analyzed strain of higher virulence.
“The immune defense is not based on a single response but a combination of factors,” emphasizes Irene Rodríguez-Gómez, another researcher involved in the study. The study reveals that each of these three proteins identified as crucial in the immune response plays a different role in the organism’s defense. T-BET is associated with activating macrophages that phagocytize the virus, FOXP3 prevents excessive inflammatory responses, and EOMES activates lymphocytes responsible for inducing the death of virus-infected cells.
Jaime Gómez-Laguna, another author of the study, highlights that while the research delves into aspects related to basic science, the results allow the identification of key factors in the immunopathology of this disease, paving the way for more in-depth studies and the development of future strategies.
Currently, there are various commercially available vaccines against PRRSV, but none provide complete protection due to the virus’s high mutation rate. The long-term goal is to develop new vaccine candidates that offer total immunity against different strains of the pathogen.
Reference: Ruedas-Torres, Inés, et al. “Activation of T-bet, FOXP3, and EOMES in Target Organs From Piglets Infected With the Virulent PRRSV-1 Lena Strain.” Frontiers in Immunology, vol. 12, 2021, 773146. DOI: 10.3389/fimmu.2021.773146.