Hypersensitivity Reactions
Hypersensitivity reactions are excessive or inappropriate immune responses that cause tissue damage, classified into four types based on mechanism and timing.
Innate and Adaptive Immunity
The immune system comprises innate and adaptive branches that work together to protect against pathogens through immediate defense and long-term memory.
Vaccines and Vaccination
Vaccines are biological preparations that induce protective immunity against infectious diseases by exposing the immune system to antigens.
