Introduction
The immune system is involved in protecting the body against attacks that would culminate in disease. The lymphatic system is composed of thousands of lymphatic vessels responsible for filtering plasma back to the blood. It also interacts with the lymphoid system that is crucial in the immunity of an organism (Marieb & Hoehn, 2010, p. 45). This paper discusses the physiology and functions of antibodies, cytokines, humoral immunity, natural killer (NK) cells, and pathogens.
Antibodies
Antibodies are substances produced by B cells. They provide a defense to an organism by activating the complement system, a process that results in the killing of pathogens. Also, antibodies activate the effector cells of the immune system by surrounding pathogens that multiply outside cells (Marieb & Hoehn, 2010, p. 23).
Cytokines
These are small proteins produced by immune cells like mast cells and B lymphocytes. They circulate in the lymphatic system dissolved in plasma. These proteins are important in regulating the functions of the humoral and cell-based activities of the immune system (Marieb & Hoehn, 2010, p. 27; Steidl et al., 2010).
Humoral immunity
Humoral immunity is a component of the immune system that is regulated by substances found in body fluids. The immunity is dependent on the production of antibodies and antibody activities (Steidl et al., 2010). The functions of humoral immunity include effector cell activation, phagocytosis, and killing of pathogens (Marieb & Hoehn, 2010, p. 87).
Natural killer (NK) cells
Natural killer (NK) cells are components of the innate immune system that appear as granular lymphocytes. The cells are crucial in fighting viral infections in the body. Also, they are important in response to tumor formation, a response aimed to eliminate tumors from body organs (Marieb & Hoehn, 2010, p. 108; Steidl et al., 2010).
Pathogens
Pathogens are substances that have the potential to cause diseases in living organisms. They cause disease by evading the immune system and altering the normal physiology of the body. They also activate components of the immune system (Marieb & Hoehn, 2010, p. 17).
Conclusion
Antibodies, cytokines, humoral immunity, natural killer (NK) cells, and pathogens are crucial components in the normal function and physiology of living systems. They help the body maintain disease-free states by altering and activating the activities of the immune system.
References
Marieb, E. N., & Hoehn, K. (2010). Human anatomy and physiology. (9th Ed.). Upper Saddle River, NJ: Pearson Education.
Steidl, C., Lee, T., Shah, S. P., Farinha, P., Han, G., Nayar, T.,… & Gascoyne, R. D. (2010). Tumor-associated macrophages and survival in classic Hodgkin’s lymphoma. New England Journal of Medicine, 362(10), 875-885.