HLT54115 Nursing

The immune system in the body comprises the complex collection of cells, molecules, and tissues that have the responsibility of defensively protecting the body against adverse effects of microbes, toxins and other related agents (4). This defence mechanism is divided into two categories namely; the innate and the adaptive defence mechanism. The innate immune system is compost of the cells and proteins that are naturally present in our body (1). They include; epithelial cells, phagocytic cells, dendritic cells, the circulating plasma cells, and the natural killer cells.  The adaptive immune system also involves the components that are silent but get triggered when an innate immune system is overwhelmed. These components include; the humoral immunity that is mediated by the B lymphocytes and the cell-mediated immunity that is also mediated by T lymphocytes (1).

The chronological approach of curing diseases more especially cancer has undergone different scientific breakthroughs like radiotherapy, chemotherapy, nutritional therapy and surgery (5). However, some of these methods have posed detrimental ramifications in the way they interact with the body as they lack selectivity by killing both the normal and cancerous cells (3) The next generation of which the biomedical scientist and the pharmaceutical industry is focusing on the cancer drugs is the issue of selectivity in a bid to reduce the side effects that patients do experience as well as reducing drug and radiation toxicity in the body while keeping in check the issue of drug efficacy. That approach is the use of immunotherapy (3).

Since the body has its own defence mechanism to fight diseases, immunity of the body, immunotherapy boosts it naturally to respond to diseases through developing antibodies, which in turn binds with the antigenic sites of the cancerous cells(4). This binding brings about the therapeutic effect of the anti-cancer agents that are used for its cure e.g. the use of Trastuzumab for breast cancer. These immunotherapy approaches have simultaneous objectives which include to; lower the rate at which cancer cells grow, stop metastasizes of the cancer cells and to boost the immune system (2).

The following types of immunotherapy have been researched and have been found to be effective (1). They include; the use of T-cell therapy, the use of a monoclonal antibody, the use of oncolytic virus therapy, the application of the non-specific immunotherapies and the use of the third generation reverse cancer vaccines. However, the use of monoclonal antibodies has gained much application (5).

 The therapeutic approach  that employs the use of monoclonal antibodies for instance, in the cure against non-Hodgkin’s lymphoma, unconjugated antibody, radioimmunoisotypes conjugates with the CD20 which in turn reacts with tumours and selectively kills them, and this approach have shown tremendous significance in the cure of the B-cell non-Hodgkin’s lymphoma(2). For the cure of Myeloid Leukaemia, the use of an ant-CD33 antibody that conjugates with calicheamicin has also been recommended. Other immunotoxins that have been of great application are the CD52 antibody has also been significantly used for the cure against lymphatic leukaemia and the use of anti-HER2 as a cure for the breast cancer which will be our point of focus(5).

The mode of action of these monoclonal antibodies has been widely and extensively explained. For instance, these antibodies possess the ability to interfere with the signalling pathway which is of great importance to sustain the malignant cells which enhance auto-tumour antigen-specific immune responses (5).

The other mechanism of action of the monoclonal antibody is the use of antibody-dependent cellular cytotoxicity (ADCC). In this approach, the antibodies bind with the antigens of the cancer cells. The Fc-receptor of the antibody then reacts with the immune cells which in turn lead to the formation of an adaptor protein that elicits the immune effector cells. For instance, in the case of breast cancer, ADCC elicits specific antibodies which subsequently induce the HER2 antibodies. Another great application of the monoclonal antibody is its effect as an adjuvant; this approach focuses on the ability of monoclonal antibodies to recruit the adaptive cancerous cells that are antigen-specific as in the case of HER2 for breast cancer.

In as much as this immunotherapy has shown tremendous achievements in curing breast cancer by the use of Trastuzumab, there still remains other challenges since the biomarkers of breast cancer, HER2 are of different subtypes. This, therefore, leads us to the next breakthrough in medicine and that is personalized medicine. For instance, the breast cancer HER2 can be of different subtypes that include, HER2+ Lumina A, HER2+ Lumina B, HER- Lumina B, HER 2 enriched etc, these subtypes make patients not to respond equally to Trastuzumab drugs. Therefore, to ensure drug efficacy that can lead to effective treatment, there is a need to employ molecular characteristics in the genetic makeup of each biomarker of breast cancer.

References

1. Home | Cancer Immunology Research [Internet]. [cited 2018]. Available from: https://cancerimmunolres.aacrjournals.org/
2. Cancer immunology – Wikipedia [Internet]. [cited 2018]. Available from: https://en.wikipedia.org/wiki/Cancer_immunology
3. Cancer Immunology – an overview | ScienceDirect Topics [Internet]. [cited 2018]. Available from: https://www.sciencedirect.com/topics/medicine-and-dentistry/cancer-immunology
4. Center for Cancer Immunology – Massachusetts General … [Internet]. [cited 2018]. Available from: https://www.massgeneral.org/cancer/services/centers/cancer_immunology.aspx
5. Cancer Immunology Named ‘Breakthrough of the Year’ – Medscape [Internet]. [cited 2018]. Available from: https://www.medscape.com/viewarticle/818181