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Key Terms

active immunity
the immune response generated by the body's own immune system after exposure to an antigen
adaptive immune system
specific defense mechanism of the immune system that develops over time and provides a targeted response to pathogens or antigens
antibodies
Y-shaped proteins produced by B cells of the immune system, also known as immunoglobulins
antibody-mediated/humoral immunity
a type of immune response that primarily involves B cells and their production of antibodies
antigen-antibody interaction
the binding of antigens (foreign substances) by specific antibodies produced by the immune system
biologic drugs
medications derived from living organisms or produced using biotechnology
biosimilar drugs
medications that are highly similar to an already approved biologic drug, known as the reference product
cell-mediated immunity
type of immune response that primarily involves T cells in recognizing and responding to specific antigens
herd immunity
the process by which a portion of a population becomes immune to a disease through either vaccination or previous infections
immune system
a complex network of cells, tissues, and organs that work together to defend the body against infections, diseases, and foreign substances
immunizations
the administration of vaccines to stimulate the body's immune system to produce a protective response against specific diseases
immunosuppressants
medications that suppress or weaken the immune system's activity
infection
when harmful microorganisms, such as bacteria, viruses, fungi, or parasites, invade the body and multiply, leading to disease
inflammation
a natural response of the immune system to tissue injury, infection, or irritation
inflammatory response
the coordinated reaction of the immune system to injury, infection, or harmful stimuli, involving a series of cellular and biochemical processes aimed at eliminating the threat and promoting tissue healing
innate immune system
the body’s first line of defense against pathogens and foreign substances
monoclonal antibodies
laboratory-produced molecules designed to mimic the immune system's natural ability to fight off specific pathogens or target specific cells
passive immunity
the temporary protection against a specific pathogen that is conferred to an individual by receiving pre-formed antibodies rather than producing them internally
titer
the concentration or potency of a substance, often an antibody, in a solution, indicating its effectiveness or level of activity
vaccine hesitancy
the reluctance or refusal to receive vaccines despite their availability and effectiveness
vaccine-preventable diseases
infectious diseases that can be effectively prevented by vaccination
vaccines
biological preparations containing weakened or killed pathogens or antigens that stimulate the immune system to produce protective immunity against specific diseases
virulent
the degree of severity or harmfulness exhibited by a pathogen, indicating its ability to cause severe disease or illness
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