This book describes Lymphocyte, Functions, Diseases, Diagnosis and Treatment and Related Diseases
A Lymphocyte is a small white blood cell that carries out the activities of the immune system
They number about one trillion.
The normal lymphocyte has a large, dark-staining nucleus with little to no eosinophilic cytoplasm.
The coarse, dense nucleus of a lymphocyte is about the size of a red blood cell (about 7 micrometers in diameter).
The lymphocytes are of 2 types:
Larger Lymphocytes called Natural Killer cells (NK cells)
Small Lymphocytes
a. B cells function mainly by secreting soluble substances called antibodies (humoral imunity)
b. T cells which are processed in the thymus and act together directly with their targets (cellular Imunity)
Life and Death of a LYmphocyte
My name is Immune Man the T-cell lymphocyte.
I was named Immune Man by my friends who think that I am able to fight any pathogen by direct contact with them.
It is true that I like to fight germs or cancer cells.
I have a partner called the B cell who has a whole arsenal of antibodies which can kill the germs or cancer cells in their body fluid. I called him Antibody Man.
B cells can be distinguished from other lymphocytes, such as T cells and natural killer cells (NK cells) by the presence of a protein on the B cell's outer surface known as a B cell receptor.
This specialized receptor protein allows a B cell to bind to a specific antigen.
Another partner is called the Natural Killer cell who is bigger than me and B cell. He killed germs or cancer cells by sending cytotoxic granules to kill them. I called him Killer Man.
Together we were the Three Amigos who fight all antigens, pathogens and abnormal body cells.
We act as the body immune system with antibodies, enzymes and toxic granules to kill the body cells which are hijacked by germs and cancer cells.
Without us the Three Amigos to protect the body cells, the human body may be over run by pathogens and mutant cells.
I was born in the bone marrow but only matured in the Thymus. The name of T cells is given to me and my brother lymphocytes.
In contrast the B cell or Antibody Man was born and matured in the bone marrow in humans.
The Killer Man or NK cell was born in the bone marrow and matured in the bone marrow, spleen, thymus, lymph nodes in the human body.
My lymphocyte cells have different functions:
T cell helper. secrete small proteins called cytokines that regulate the active immune response
Cytotoxic T cells, destroy virally infected cells and tumor cells.
Memory T cells remember how to counter past infections
Regulatory T cells (Treg cells shut down T cell-mediated immunity toward the end of an immune reaction and to suppress auto-reactive T cells
Natural killer T cells recognize and eliminate some tumor cells and cells infected with herpes viruses.
My friend the Antibody Man produces antibodies in the body to kill abnormal body cells which are attacking the body
There are nine antibodies which are produced by Antibody Man called human immunoglobulins (Ig)-four kinds of IgG and two kinds of IgA, plus IgM, IgE, and IgD
My other partner Killer Man is larger than us and is activated in response to interferons.
Like my Cytotoxic T-cell, Killer Man also contains granules filled with potent chemicals
Antibody Man has a large arsenal of antibodies to fight germs.
if one of us is unable to kill the pathogen, the other two will.
That is why we are called the Three Amigos.
Our life span can vary from a few days to many years.
Some of us will be killed by the pathogen before our amigos manage to kill it.
Our memories remain on how we were able to kill the pathogen
TABLE OF CONTENT
Introduction
Chapter 1 Lymphocyte, Functions, Di