According to Smith and Fernhall, blood is composed mainly of formed elements and plasma (Smith and Fernhall, 2011). Formed elements include erythrocytes or red blood cells, leukocytes or white blood cells and thrombocytes or platelets, and they make up about 40%-45% of the blood volume (Smith and Fernhall, 2011). The rest of the blood volume is composed of plasma, which is about 55% to 60% (Smith and Fernhall, 2011). Leukocytes consist of only 1% of the formed elements found in blood, however, play a very crucial role when it comes to our body’s defense and immune function (Smith and Fernhall, 2011). Any disorder or malfunction of a leukocyte could cause a problem in the body’s immune response. For example, sickle cell disease severity has been shown to increase as leukocyte counts increase in the body (Qari and Zaki, 2011). In patients who suffer from sickle cell disease, leukocytes in the blood adhere to blood vessel walls causing different reactions including damage to endothelial tissue and causing vaso-occlusion (Qari and Zaki, 2011). One specific leukocyte (neutrophil), which may be involved in the propagation of vaso-occlusion, are larger and more difficult to deform than erythrocytes. This can increase the risk of vaso-occlusion (Qari and Zaki, 2011).
Endometriosis is a chronic reproductive disease that effects 1 in 10 women, including myself. There is no proven cause of endometriosis, however it has been shown that “when endometrial leukocyte populations are dysregulated in number and/or function, the ability of the uterus to correctly regenerate the endometrium and/or eliminate shed endometrial cells is likely to be dysregulated as well” (Parkin and Fazleabas, 2015). Leukocytes, in patients with endometriosis, also contribute to the growth and survival of lesions by promoting a pro-growth and pro-survival environment for ectopic endometriosis, rather than destruction (Parkin and Fazleabas, 2015). So, we see here that even though leukocytes, which play a “good” role in our immune system response and body defenses, when dysregulated can cause problems and illnesses that actually lower our immune response.
- Parkin, Kirstin L. and Fazleabas, Asgerally T. (2015) Uterine leukocyte function and dysfunction: a hypothesis on the impact of endometriosis. American Journal of reproductive Immunology 2015, 411-417.
- Qari, Mohamad Hasan and Zaki, Wed A. (2011) Flow cytometric assessment of leukocyte function in sickle cell anemia. Hemoglobin 2011, 367-381.Smith, Denise L. and Fernhall, Bo. (2011) Advanced Cardiovascular Exercise Physiology Champaign, IL: Human Kinetics