Under certain conditions our physical barriers does get breached. Luckily, our bodies have another line of defenses to handle the threat and prevent any long term issues from occurring.
This section will go over what happens when something make’s it past our physical barrier.
Basics of the Innate Immune Response
The innate immune response is quite complex and there’s a huge amount of variability (based on the pathogen, location and various other factors) in it’s approach. And understanding all the small details is outside the scope of this book.
Nonetheless, immediately following a breach (of the physical barrier), these two main steps make up the basis of its approach:
Step 1 – Initial Innate Immune Response
Once our cells become aware of the breach, the first part of the defense process is initiated. Inflammation is triggered, defense cells present at the site immediately go to work, and various proteins are activated to assist.
In tandem, the various cells involved in the initial defense begin sending signals for reinforcements.
Inflammation is essential
Inflammation is very important at this point, as it increases local blood circulation, helping deliver more troops and isolating the area (preventing further spreading).
Step 2 – Mounted Innate Immune Response
The signals sent out in step one reach their destinations and various white blood cells are recruited to assist in the defense. The specific cells that rush to the scene will heavily depend on the issue at hand, but the most prominent ones include:
- Neutrophils – the most abundant white blood cell
- Macrophages/monocytes – the largest white blood cells
- Lymphocytes – main types include T-cells and B-cells
- Basophil – mainly responsible for releasing chemical signals
- Eosinophils – high involved in allergic reactions and dealing with parasites
In addition to white blood cells, various proteins are called in to assist in the defense. These proteins are termed as the “complement system” and a brief discussion of them is provided later in this chapter.
Some responders are quicker then others
Scavenger cells and various phagocytes are usually some of the very first responders. They are multi-talented and are effective at combating a large variety of pathogens.
This section went over what happens when the physical barrier is breached and covered the main components of the innate immune response.
- If pathogens make it past the physical barrier they are met by the various defense cells of our bodies
- The innate immune response can be quite complex and variable, but its general approach can be divided into two main steps
- Step one is the initial response to the invader, it involves the activation of present defense cells, inflammation and signaling for reinforcements
- Step two covers the migration of white blood cells recruited during the first step and activation of various defense proteins