Section outline

  • Hi everyone!
    In today’s session, we’ll move beyond surface defenses to explore the second line of defense. This system comes into play when pathogens breach the first line, for example, through a cut or when inhaled. The second line is part of your innate immune system, which means it responds rapidly and in the same way to all invaders. This line includes powerful processes like inflammation, fever, and the action of white blood cells such as phagocytes. Though it's not specific to any one pathogen, it plays a vital role in controlling infections early on. Let’s take a closer look at how this works.


    12.1 Topic Learning Outcome
    By the end of this lesson, you will be able to:
    12.1.1 Define the second line of defense.
    12.1.2 Identify key immune cells involved in this line of defense.
    12.1.3 Describe the role of phagocytosis, inflammation and fever.


    12.2 List Subtopics
    12.2.1 Definition and purpose of second line of defense
    12.2.2 Phagocytosis and Phagocytes
    12.2.3 Inflammation and its role
    12.2.4 Fever as a defense mechanism
    12.2.5 Natural Killer cells and interferons

    12.3 Lecture Video

    Phagocytosis 


    Inflammation 


    Interferon 


    Fever 


    Natural Killer Cells