Immunologists are scientists who study the immune system, which is the body's defense mechanism against infections and diseases. They investigate how the body recognizes and responds to harmful pathogens like bacteria and viruses, as well as how it distinguishes between harmful and harmless substances. Their research helps in understanding various immune-related conditions, including allergies and autoimmune diseases. These specialists often work in laboratories, conducting experiments to develop vaccines and treatments that enhance immune responses. They may collaborate with other healthcare professionals, such as doctors and pharmaceutical companies, to translate their findings into practical applications that improve public health.