An ability of the immune system to adapt itself with disease and to generate pathogen-specific immunity is termed as acquired immunity and also known as adaptive immunity.
In innate immunity, the immune system blocks the entry of all the microorganisms and tuned to remember the various diseases it has faced over time and respond in a manner specific to each disease. The line of division between the innate and adaptive immunity is that the innate immune system is composed of primitive bone marrow cells that recognize foreign substances and reacting to them, whereas the adaptive immunity consists of an advanced lymphatic defense system functions by recognizing the own body cells and not reacting to them.
In this immune system, our body identifies the pathogens which have encountered in the past. Acquired immunity or adaptive immunity occurs when we come in contact with the pathogen or its antigen. Antigens are the generator of antibodies.
Our body starts producing antibodies to engulf the pathogen and destroy its antigen. When it encounters for the first time, it is called a primary response. Once a body gets used to this pathogens, antibodies are ready to attack them for the second time and are known as naturally acquired immunity.
Vaccinating pathogenic microorganisms into our body deliberately produces a similar response and is termed as artificially acquired immunity. Immunization is a process providing resistant to pathogenic microbes and other infectious diseases by the administration of a vaccine into the body. By immunization, it stimulates the body’s immune system to protect against subsequent infection or disease.
Acquired immunity comprises of two special cells called B-lymphocytes and T-lymphocytes. In the case of an infection, the adaptive immune response is characterized by the B-lymphocytes producing huge amounts of proteins called Antibodies. While T-cells do not make the protein themselves, they help the B-cells with the production. This antibody protein consists of four chains of peptide molecules, two small chains called light chains and other two called the heavy chains.
Our acquired immune response are of two types:
Humoral immune response:
The antibodies produced by B-lymphocytes are present in the blood and they are transported all over the body. This is why it is called the humoral immune response as it consists of an antibody army produced by the lymphocytes.
Cell-mediated immune response:
The T-lymphocytes are responsible for this immunity. Cell-mediated immunity becomes clear in the case of transplant patients. When one of our sense organs malfunctions, we can transplant and replace the malfunctioning organs with it. But it is not that simple with the immune response. It appears that T-lymphocytes are capable of recognizing whether a tissue or an organ is from our body or someone else’s. This is the reason why we cannot transplant and implant the organs into our body even if we find the donor with the same blood group, our body might reject the transplant. The T-cells quickly recognize that the tissue is foreign and do not allow it to become a part of the body. This is why transplant receivers have to take immune-suppressant medication for the rest of their lives. This response is controlled by the T-lymphocytes.
The T-cells quickly recognize the foreign tissue and do not allow it to become a part of the body. This is why transplant receivers have to take immune-suppressant medication for the rest of their lives. This response is controlled by the T-lymphocytes.
Our immune system is beautifully tuned to protect us from the microorganisms around us and it is constantly improving.