Published online by Cambridge University Press: 07 September 2010
MAJOR IMMUNE CELL TYPES AND THEIR FUNCTIONS
Pathogen invasion of an immunocompetent host induces a coordinated response from a network of diverse immune cell types. The interactions between these various immune cell types are spatially and temporally regulated to facilitate the acquisition of effector mechanisms that ensure pathogen clearance. This section briefly summarizes the major components of the immune network and their actions during an immune response. A more detailed description of the development and function of specific immune cell types can be found in.
The immune network has two major components: the innate and adaptive immune systems. Cells of the innate immune system such as macrophages and dendritic cells generally make first contact with pathogens. Pathogen-derived molecules activate specific receptors on innate immune cells leading to the release of chemo-attractant molecules and recruitment of other inflammatory cells such as neutrophils. Furthermore, macrophages and dendritic cells ingest foreign proteins (or antigens) and migrate to nearby lymph nodes where they serve as antigen-presenting cells (APCs) in the initiation of the adaptive immune response.
T and B lymphocytes are the key cell types of the adaptive immune system. Both B and T cells express dedicated and highly variable cell surface receptors for antigen. Exposure to antigen together with help from T cells activates B cells to proliferate and differentiate into plasma cells that secrete antigen-specific antibodies that, by various effector mechanisms participate in antigen clearance. Once the invading pathogen has been cleared, the expanded antigen-specific B cell population contracts through apoptosis.
To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.