Hi, WelcOmE to Back mY Blog Article. Let's learn about adaptive immunity. The human body has a number of ways to fightoff nasty pathogens. There are 2 types of adaptive or specificimmunity.
Cell mediated and antibody mediated. This Article covers antibody mediated immunity. B lymphocytes or B cells are involved in antibodymediated or humoral immunity. B-cells are activated by co-stimulation whichinvolves a connection between an antigen receptor on the B-cell and an antigen from a pathogen.
Here, an antigen from a pathogen is displayedon a macrophage which acts as an antigen presenting cell. Along with the antigen antigen-receptor connection,substances called cytokines are secreted by the macrophage which also help to activatethe B-cell.
Activated B-cells secrete antibodies. Activated B-cells are called plasma cells. Here is an antibody. Antibodies contain constant and variable portions. The variable portions connect with regionson antigens called antigenic determinants. The constant region can activate a seriesof plasma proteins called the complement system.
Antibodies can connect to antigens and disablethem. Antibodies can bind antigens together. Antibodies can connect to mast cells promotingthe release of substances that cause inflammation. Antibodies bound to antigens can stimulatephagocytosis. There are several types of antibodies or immunoglobulins. IgG antibodies are the most abundant type. They protect against viruses and bacteriaand can cross the placenta. IgE antibodies are secreted by plasma cellsin skin, GI/Respiratory tracts and tonsils. They trigger inflammation.
IgD antibodies bind to B-Cells and functionas antigen receptors. IgA antibodies are found in sweat, saliva,intestines. They prevent pathogens from attaching to epithelialsurfaces. IgM antibodies can activate the complementsystem, act as antigen receptors on B-Cells and cause agglutination in the ABO blood typingsystem. IgM antibodies can activate the complementsystem. The complement system forms membrane attackcomplexes that drill holes in pathogens.
the complememt systemby way of the classical pathway. Upon first exposure to a pathogen, the immunesystem produces antibodies to fight it off. This is known as the primary immune response. Activated B-cells clone themselves. Some of these clones serve as memory cellsthat can immediately secrete antibodies if exposed to the same pathogen.
This is called the secondary immune response. There are 4 types of immunity. In naturally acquired active immunity, thebody is exposed to a pathogen and responds by making antibodies.
A vaccine is a good example of artificiallyacquired active immunity. Here, antigens are given and the body makesantibodies to produce immunity. In naturally acquired passive immunity antibodiesare transferred from the placenta to the fetus. In artificially acquired passive immunity,
antibodies are given to someone who's immune system is damaged. I hope you have learned something about antibody-mediated immunity and read you next article
Comments
Post a Comment
If you like this article useful and good, then share, make sure to comment.😘😘