IMMUNOLOGY

OVERVIEW OF THE IMMUNE SYSTEM

A HISTORICAL PERSPECTIVE OF IMMUNOLOGY

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
What is the first line of defense against pathogens?
A
phagocytes
B
Natural Killer Cells
C
Skin and mucous membranes
D
Inflammatory response
E
Fever
Explanation: 

Detailed explanation-1: -The innate immune system is the body’s first line of defense against germs entering the body. It responds in the same way to all germs and foreign substances, which is why it is sometimes referred to as the “nonspecific” immune system.

Detailed explanation-2: -Skin is a barrier that serves as one of the body’s first lines of defense against harmful microbes. Specialized immune cells within skin tissue help to fight invading organisms. Yet the skin hosts diverse communities of beneficial bacteria, collectively known as the skin microbiota.

Detailed explanation-3: -Skin, tears and mucus are part of the first line of defence in fighting infection. They help to protect us against invading pathogens.

Detailed explanation-4: -“White blood cells are among other places located in the oral mucosa, and they represent the body’s first line of defence against infectious agents. The mucus in the mouth causes the white blood cells to throw out a ‘net’ that traps bacteria”, explains Ole Sørensen from the Division of Infection Medicine.

Detailed explanation-5: -The epidermis comprises the outermost layers of the skin. It forms a protective barrier over the body’s surface, responsible for keeping water in the body and preventing pathogens from entering.

Detailed explanation-6: -The first line of defence is your innate immune system. Level one of this system consists of physical barriers like your skin and the mucosal lining in your respiratory tract. The tears, sweat, saliva and mucous produced by the skin and mucosal lining are part of that physical barrier, too.

Detailed explanation-7: -Keratinocytes. Keratinocytes are the predominant cells in the epidermis. They act as the first line of innate immune defence against infection. They express Toll-like receptors (TLRs), which are pattern-recognition receptors (PRRs) that detect conserved molecules on pathogens and trigger an inflammatory response.

There is 1 question to complete.