T Lymphocytes And Cell-Mediated Response Flashcards
Where are all lymphocytes made?
In the bone marrow.
Where do T lymphocytes mature?
In the thymus.
What are lymphocytes?
White blood cells involved in the specific immune response.
What are antigen presenting cells?
Cells that present a non-self antigen on their surface.
What does the cell-mediated response involve?
T cells.
What are the 4 types of cells that present antigens on their surface?
Infected body cells, a phagocyte that has destroyed a pathogen, transplanted organ cells, and cancer cells.
Why are T cell responses described as ‘cell-mediated’?
As T cells only respond to antigens which are presented on cells, and not antigens detached from cells within bodily fluids such as the blood.
What happens after a pathogen has been engulfed and destroyed by a phagocyte?
The antigens are positioned on the cell surface and the cell is now an antigen-presenting cell.
What do helper T cells have?
Receptors on their surface.
What do helper T cells do with the antigen-presenting cell?
The receptors on their surface attach to the antigens on the antigen-presenting cell.
What happens once the receptors on the helper T cell attach to the antigen-presenting cell?
This activates the T helper cells causing them to divide by mitosis and make large numbers of clones.
What are the different cells that cloned helper T cells differentiate into?
Some stay as helper T cells and activate B lymphocytes, phagocytes to perform more phagocytosis, memory cells for that antigen, and cytotoxic T cells.
What do cytotoxic T cells do?
Destroy abnormal or infected cells.
What do cytotoxic T cells release?
A protein called perforin.
What does perforin from cytotoxic T cells do?
Embeds in the cell surface membrane and makes a pore so substances can enter and leave the cell, causing it to die.
