The immune system is a complex process that involves the interaction of various biological components in the body that are involved in defending the body against infections. As such, because of this immune system complexity, there is no single approach that can be reliably used in the determination of this system’s efficacy. Currently, there are various approaches that are widely used in assessing the efficiency of the immune system against key components but as varied as they are, they can generally be categorized into two, i.e., in vitro assays and in vivo assays. In this section of the paper, our focus will be on two of these approaches, namely lymphocyte subsets, and cytotoxicity assays.
The lymphocyte subset immune determination method is pegged on assessment of the proportion and numbers of known body cells that are directly involved in body defense mechanism. It relies on a technique referred to as fluorescence-activated cell sorting analysis that is basically used to provide an aggregate figure of various antibodies that are found in the body. The advantage of this method is that it is sensitive enough to provide an accurate determination of an individual’s immunity effectiveness based on the results of the analysis since it indicates the percentage of each cell subset of the subject. On the other hand, this method is limited by the fact that all body cells including those involved in immunity such as T-cells and CD4 cells are constantly shifting in terms of numbers and percentage; this means that such results are only relevant at a specific point in time.
The other method is the cytotoxicity assay; this method focuses on measuring the level of cytotoxicity rate occurring in the body driven by two key body immunity cells, the NK cells and T cells. The idea is to determine the rate at which NK and T cells are forging cytotoxicity activities within the body and therefore infer from this activity the immune efficacy of the subject. This method’s main advantage is that it can effectively determine the strength of a person’s immunity level by focusing on one aspect of the immunity system, cytotoxicity. However, it is disadvantaged in that determination of NK-caused cytotoxicity in the body system is at best a difficult and complex process that cannot be reliably depended upon due to the complex antibody-antigen interaction that is involved.