The Innate Immune System

Compare and contrast the biological processes underlining the innate and adaptive immunity

The complexity of the human immune system comprises of specialised cells(leukocytes), proteins (antibodies, lysozymes), tissues (lymphatic vessels), and organs (spleen) working together to fight off pathogens due to constant exposure. The first line of defence is the innate immune system which reacts rapidly to the pathogens. Whilst the adaptive immune system responds slowly to infection and also possesses a high degree of specificity. However, it is the activities of the innate immune system that prompt the response of the adaptive immune system.

The innate immune system, known as the non-specific defence mechanisms uses various components to protect

Unlike the adaptive systems, the cells of the innate systems do not mature into other tissues. Neutrophils are rapid responders to the site of infection and are efficient phagocytes with a preference for bacteria. Their granules contain lysozymes; oxidants; and defensins, proteins that bind to and puncture bacterial and fungal plasma membranes. The granules of basophils release histamines, which contribute to inflammation, and heparin, which opposes blood clotting. The cells of the innate systems neutralise the actions the basophils. The granules of eosinophils include antihistamine molecules; which counteract the activities of histamines. Eosinophils are particularly effective when antibodies bind to the target and form an antigen-antibody complex. Macrophages release antimicrobial defensins and chemotactic chemicals that attract other leukocytes to the site of an infection. NK cells are capable of recognizing cells that do not express “self” proteins on their plasma membrane. These “non-self” cells include cancer cells, cells infected with a virus, and other cells with atypical surface proteins. Thus, providing generalized, non-specific

B lymphocytes and T lymphocytes, play prominent roles in defending the body against specific pathogens and are involved in the adaptive immunity. Unlike the cells of the innate system, B cells have various isomers. One form of B cells (plasma cells) produces the antibodies that bind to specific foreign or abnormal components of plasma membranes. T cells provide cellular-level immunity by physically attacking foreign or diseased cells. A memory cell is a combination of B and T cells that form after exposure to a pathogen and mounts rapid response. Unlike other leukocytes, memory cells live for many