Four Types of Immunity

Summary

Dr. Mike explains the adaptive immune system and the four ways we acquire immunity: active and passive immunity, each with natural and artificial forms. Active immunity involves the body creating its own antibodies, either naturally through infection or artificially via vaccination. Passive immunity, on the other hand, involves receiving pre-made antibodies, either naturally from maternal sources like breast milk or artificially through medical interventions like blood plasma. The video highlights the mechanisms and importance of these different types of immunity.

Takeaways

• 🛡️ The immune system is divided into the innate and adaptive immune systems.
• 🧠 The innate immune system is nonspecific and does not create immunological memory.
• 🧬 The adaptive immune system is specific and does create immunological memory to specific pathogens.
• 🔬 Immunological memory can be acquired through four different methods: two active and two passive.
• 🏋️‍♂️ Active immunity involves the body creating its own antibodies.
• 🌱 Naturally acquired active immunity occurs when the body creates antibodies in response to an infection from the environment.
• 💉 Artificially acquired active immunity happens when the body is exposed to a pathogen through vaccination, allowing it to create antibodies.
• 🍼 Passive immunity involves receiving pre-made antibodies from an external source.
• 👶 Naturally acquired passive immunity occurs when a baby receives antibodies from the mother through breast milk.
• 💉 Artificially acquired passive immunity involves receiving antibodies through blood plasma or serum, such as in the case of rabies or tetanus treatment.

Q & A

What are the two main components of the immune system?

The two main components of the immune system are the innate immune system and the adaptive immune system. The innate immune system is nonspecific and does not create immunological memory, while the adaptive immune system is specific and does create immunological memory to specific pathogens.

What is the difference between innate and adaptive immunity in terms of specificity and memory?

Innate immunity is nonspecific and does not create any immunological memory to pathogens. In contrast, adaptive immunity is specific and does create immunological memory, allowing the body to recognize and respond more effectively to future encounters with the same pathogen.

How can immunological memory be acquired?

Immunological memory can be acquired through four different ways, categorized into two major types: active and passive. Active immunity involves the body creating its own antibodies against a pathogen, either naturally through infection or artificially through vaccination. Passive immunity involves receiving preformed antibodies, either naturally through maternal antibodies in breast milk or artificially through the administration of antibodies from another source.

What is naturally acquired active immunity?

Naturally acquired active immunity occurs when the body mounts an immune response to a pathogen from the environment, such as during an infection, and creates antibodies with immunological memory against that specific infection.

Can you explain artificially acquired active immunity?

Artificially acquired active immunity is achieved through vaccination. An example is the polio vaccine, where exposure to an inactivated form of the infection prompts the body to create antibodies, thus creating immunological memory without the risk of the disease.

What is naturally acquired passive immunity?

Naturally acquired passive immunity is when an individual receives preformed antibodies, typically through maternal antibodies in breast milk, which helps protect the infant who is not yet able to mount its own immune defense.

How is artificially acquired passive immunity achieved?

Artificially acquired passive immunity involves receiving preformed antibodies from another person or animal, often through blood plasma or serum. This can be used for post-exposure prophylaxis, such as in the case of suspected rabies or tetanus infection, where there is not enough time for the body to create its own antibodies.

What is the role of maternal antibodies in naturally acquired passive immunity?

Maternal antibodies, which are preformed antibodies passed from mother to child through breast milk, play a crucial role in naturally acquired passive immunity by providing the infant with immediate protection against certain infections until their own immune system is developed enough to respond.

Why is vaccination an example of artificially acquired active immunity?

Vaccination is an example of artificially acquired active immunity because it involves the introduction of an inactivated or weakened form of a pathogen to stimulate the body to produce its own antibodies and memory cells, thus creating immunological memory without causing the disease.

What is the significance of immunological memory in the adaptive immune system?

The significance of immunological memory in the adaptive immune system is that it allows for a faster and more effective response to subsequent encounters with the same pathogen. This is crucial for long-term protection against infectious diseases.

How does the body distinguish between active and passive immunity when responding to a pathogen?

The body distinguishes between active and passive immunity based on whether it is creating its own antibodies (active immunity) or receiving preformed antibodies from an external source (passive immunity). Active immunity involves the body's own immune response, while passive immunity involves the transfer of antibodies without the need for the body to produce them.