23 April 2019
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Head of laboratory
Dr Zohreh Babaloo, Assistant Professor (PhD)        

E-mail:  babalooz@tbzmed.ac.ir


Dr Jafar Majidi, Professor (PhD)

Dr Mohammad Reza Bonyadi, Assistant Professor
 (Doctor in Medical Laboratory Sciences)
bonyadir@tbzmed.ac.ir , bonyadir@yahoo.com

Dr Behzad Baradarn, Assistant Professor (PhD)

Dr Jalal Abdolalizadeh, Assistant Professor  (PhD)
jabdolalizadeh@hotmail.com, abdolalizadehj@tbzmed.ac.ir

Maryam B Amirkhiz (MSc)
E-mail:  amirkhizb@yahoo.com



Overview of Immunology:

The immune system consists of factors that provide innate and acquired immunity, and has evolved to become more specific, complex, efficient, and regulated. One of the principal functions of the human immune system is to defend against infecting and other foreign agents by distinguishing self from non-self (foreign antigens) and to marshal other protective responses from leukocytes. The immune system, if dysregulated, can react to self antigens to cause autoimmune diseases or fail to defend against infections.

Immunoglobulins (antibodies) are globular glycoproteins found in body fluids or on B cells where they act as antigen receptors. These molecules are either expressed on the surface of B cells or are secreted by terminally differentiated cells from this lineage (plasma cells) into the circulation or external secretions. An immunoglobulin molecule is a symmetrical multi-chain peptide consisting of two identical H chains and two identical L chains. Each chain is divided into a V region that is responsible for specific antigen binding and a C region that carries out other functions such as the binding of IgG to complement or leukocytes. These antibody molecules are formed as a result of the assembly of separate germ-line genes for the V, J, and C regions of the H and L chains of the final immunoglobulin molecule. This combinatorial mechanism is responsible for the great diversity of antibody molecules.There are five major isotypes (classes) of immunoglobulins (IgG, IgA, IgM, IgD, and IgE). These isotypes are distinguished by differences in the C regions of H chains of each immunoglobulin isotype (gamma, alpha, µ, delta, and epsilon, respectively). These differences are responsible for the particular functions of immunoglobulin classes.Initial exposure to an antigen results in the production of low affinity antibodies, but continued exposure to antigen leads to the production of high affinity antibodies. In the primary antibody response (the first immunization), B cells are activated to produce IgM antibody. By 3-5 days, specific antibodies, mainly of the IgM isotype, appear in the serum and the concentration (titer) increases until a peak is reached in 10-14 days. Antibody titers then fall to preimmunization levels after some weeks. Upon reimmunization, there is a more rapid and extensive development of antibody-producing cells in regional lymph nodes, and many of them undergo an isotype switch to produce IgG or other immunoglobulin classes of specific antibodies. As a result, in most cases following re-immunization, serum antibodies are primarily IgG and have a greater affinity for antigens; also, the antibody titers are higher and persist for much longer periods.

Immunology emerged from medical science and has permeated all biology. The spread of immunology into other fields has been the result of the scientist and clinician using immunologic techniques as a sensitive analytical tool. Immunological assays are important in regulatory work because of their sensitivity, specificity, and rapidity.  The research topics that are investigated in the immunology laboratory are as follows:

 HLA and diseases
There is a genetic relationship between HLA antigens and special diseases like autoimmunity.  Special antigens of autoimmunity diseases like Myastenia Gravis, Behcet's Syndrome etc. are determined by recognition of HLA antigens on leukocytes using HLA-Typing method.
  Production of polyclonal and monoclonal antibodies against different antigens
Monoclonal antibodies are important in immunology.  They are very useful for making ELISA, Immunofloresance and Immunohistochemistry kits.  Also monoclonal antibodies conjugated with drug or poison are used for curing some Leukemia diseases.
Cell culture
Cell culture has a very broad application in Molecular biology, Immunology and Hematology.  Cell culture is used for investigating of effects of medicines on producing special products by cells.  Cell culture is basis of monoclonal antibodies production and is essential for investigating of drugs effects.
 Isolation and purifications of proteins
Protein purification has  wide applications in different sciences such as immunology, biochemistry and production of biologic materials.  Making ELISA and Radio immunoassay kits require purification of proteins like immunoglobulins that are produced by Gel filtration, Ion exchange and affinity chromatography methods.