Lymphocyte Proliferation Assay

The Lymphocyte Proliferation Assay (LPA) measures the lymphocytes' capacity to proliferate clonally when stimulated in vitro by an additional antigen, mitogen, or chemical. LPA involves obtaining a sample of the victim's white blood cells and subjecting them to mitogens in order to qualitatively examine the immune system. The mitogen will multiply or divide normal cells to a predetermined degree determined by the criteria. However, if the response falls short of the required levels, infections could result. A mitogen is a chemical element that stimulates the cell division thus triggering mitosis. They are protein compounds comprising of amino acids which stimulate biochemical responses in organisms. Mitogens are common in the immunology field since they can induce signal transduction trails. The pathways are processes within an organism where biochemical “signals” from the exterior to the inside parts modify the cell. A good example is the mitogen-activated protein kinase (MAPK) that sometimes mutates to cause cancer. During mitosis, a cell separates into two identical daughter ones. They split to share the generic material to each of the daughter cells. The mitosis process permits a cell to duplicate itself. A mitogen functions when it interacts with the cell membrane to provoke a reaction that results in mitosis. Mitogens enhance mitosis of white blood cells or lymphocytes which can guard an organism from viruses or bacteria. However, the mitotic capability of the lymphocytes can be utilized to ascertain the functionality of the immune system (Opdenakker et al. 2012, p. 7828).

In terms of T-lymphocytes, the mitogens stimulate them to produce smaller lymphocytes that facilitate the production of lymphokines. These substances alter the host organism to enhance its immunity. The reactions are different for B-lymphocytes that produce plasma cells, antibodies or immunoglobulin. In addition, resistance in the organisms is improved when mitogens reinforce the T-lymphocytes to produce the lymphokines (Opdenakker et al. 2012, p. 7829).

Question (b)

Cyclosporine A (CsA) inhibits T-cell proliferation as well as lymphokine production. However, a pharmacologic amount of CsA, typically 10ng/ml, can block the lectin- and antigen-driven interleukin 2 secretions without impacting on cell proliferation. Additionally, a monoclonal hybridoma, which is induced by concanavalin A, effuses Colony Stimulating Factors (CSF), and interleukin 2 is concurrently clogged by CsA. The results show that, apart from blocking the stimulation of lymphokine secretion, CsA does the same with ongoing interleukin 2 production via the interference of the effective interaction of antigen and receptor. However, hindering the interleukin 2 discharge from the pre-activated cells by cyclosporine A happens approximately by 1 to 2 hours, the amount of time necessary to halt interleukin 2 production through the extraction of Ag/Lectin stimulator (“Cyclosporin A Inhibits Colon Cancer Cell Growth Independently of the Calcineurin Pathway”).

As for T cells, CsA directly interferes with the binding of Ag- to Ag-receptor leading to blockage of induction as well as active discharge of multiple lymphokines. CsA forms a multifaceted immunophilin that prevents Ca2+/calmodulin-dependent serine-threonine phosphatase calcineurin. The inactive calcineurin cannot stimulate the nuclear factor of the T cells. Therefore, it lowers the body’s immune system which assists the body to fight infections. In addition, it can reject a transplanted organ by treating it as an invader. In that regard, CsA’s action is used medically to prevent organ rejection. It enhances graft survival in bone-marrow and organ- transplant recipients. In general, except above-mentioned actions, due to the lowering of the immune system, they can also develop cancer (“Cyclosporin A Directly Inhibits Human B-cell Proliferation by More than a Single Mechanism”).

In conclusion, a mitogen is a chemical element that stimulates cell division and in T-lymphocytes, they stimulate them to produce smaller lymphocytes that facilitate the production of lymphokines. On the other hand, Cyclosporine A (CsA) inhibits T-cell proliferation as well as lymphokine production. These reactions are different in various elements like B-cells. As such, Lymphocyte proliferation assay (LPA) is a vital procedure, particularly in immunology.



References

Hannam-Harris A.C., Taylor D. S., & Nowell P.C. (1985). Cyclosporin A Directly Inhibits Human B-cell Proliferation by More than a Single Mechanism. [Online] Available at: https://www.ncbi.nlm.nih.gov/pubmed/3875675[Accessed 16 March 2017].

Opdenakker K., Remans T., Vangronsveld K., & A. Cuypers, 2012. Mitogen-Activated Protein (MAP) Kinases in Plant Metal Stress: Regulation and Responses in Comparison to Other Biotic and Abiotic Stresses. International Journal of Molecular Sciences, pp. 7828-7853.

Miriam Werneck, Eugênio Hottz, Patrícia T. Bozza, & João P.B. Viola, 2012. Cyclosporin A Inhibits Colon Cancer Cell Growth Independently of the Calcineurin Pathway. [Online] Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3507495/[Accessed 16 March 2017].