Advanced Dental Admission Test (ADAT)

What role does IL-8 play in the immune response?

1. Acts as a cytokine that suppresses inflammation

2. Stimulates the production of antibodies

3. Acts as a chemoattractant for leukocytes

4. Inhibits T-cell activation

The correct answer is: Acts as a chemoattractant for leukocytes

Interleukin-8 (IL-8) is primarily recognized for its function as a chemoattractant, particularly for neutrophils, which are a type of white blood cell that plays a crucial role in the innate immune response. When an infection or injury occurs, IL-8 is produced by various cells including macrophages and epithelial cells. It helps to recruit leukocytes to the site of inflammation by guiding them to the area where they are needed. This recruitment is essential for the efficient response to pathogens, as it enhances the influx of these immune cells, allowing for a more robust reaction to infections. By effectively drawing leukocytes to the site of infection, IL-8 facilitates the clearance of pathogens and the initiation of the healing process. Therefore, its role as a chemoattractant is fundamental to the body's ability to mount an effective immune response. Other options do not accurately reflect the primary functions of IL-8. For instance, while some cytokines do suppress inflammation, IL-8 does not perform this function; instead, it promotes inflammatory processes. Additionally, IL-8 is not directly involved in stimulating antibody production or inhibiting T-cell activation, which are functions attributed to other immune mediators.