What is HIV?
The Human Immune System
* In order to understand HIV, one must understand the human immune system. The first line of defense is a person’s skin, mucous membranes, and other secretions which prevent pathogens from ever entering your body. Pathogens are considered things your body does not want, for example bacteria and viruses.
* The second line of defense includes nonspecific mechanisms which attempt to contain the spread of pathogens throughout one’s body. The second line of defense relies heavily on the use of white blood cells, which ingest invading organisms. About 5% of white blood cells are made of monocytes, which develop into macrophages. The role of these macrophages is vital to the human immune system, as they are able to engulf pathogens without having to self destruct.
* The body’s third line of defense is a highly specific means of distinguishing “self” from “non-self” and destroying all “non-self”. All of one person’s cells are marked with a unique set of proteins which label them as “self”. Certain cells in the body are capable of recognizing every antigen (molecules belonging to viruses/bacteria) that may enter one’s body over a lifetime. These cells include macrophages, T-Cells, B Cells, and interior thymus cells. These cells rely on Helper T-Cells to alert them of antigens in the body, thus creating an immune response. Once recognized, Killer T-Cells actively destroy pathogens and even the body’s own cells if that have been invaded by a pathogen.
How HIV attacks the Body
* As commonly known, HIV cannot penetrate your immune systems first line of defense. You cannot contract HIV by breathing bad air or by holding the hand of somebody who is HIV positive. You have to wo...
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... lymphocytes. Phipps and Branch observed Fyn Kinase activity in patients with and without HIV. Those with HIV contained high Fyn Kinase activity and low levels of Fyn protein. They also found that Fyn Kinase activity increases within 30 minutes of infection of the CD4+ T cells. This new-found information revolutionized the way testing for HIV occurs.
References:
Alkhatib, G. et al, "CC CKR5: A RANTES, MIP-alpha, MIP-1 beta Receptor as a Fusion Cofactor for macrophage-tropic HIV-1." Science 272, 1955 (1996).
Grimes, W., R. Hallick, M. Hewlett, J. Aronson, and B. Fishel. Biology 181 Laboratory Manual 2002. Hayden-McNeil Publishing, Inc.
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Purves, W., D. Sadava, G. Orians, and H. Heller. Life: The Science of Biology , Sixth Edition 2001. Sinauer Associates, Inc.
It is crucial to understand that, unlike most transmissible diseases, AIDS/HIV is not transmitted through sneezing, coughing, eating or drinking from common utensils, or even being around an infected person. Casual contact with AIDS/HIV infected persons does not place others at risk. HIV/AIDS can be passed through unprotected sex with an infected person, sharing contaminated needles, from infected mother to baby during pregnancy, birth or breastfeeding, and through direct exposure to infected blood or blood
The immune system is made up of a network of cells, tissues, and organs that work together to protect the body, and it defends the body from “foreign invaders.” Immunity can be divided in two three different defenses, and these are defined as first, second and third lines of defense. The first line of defense for the immune system is the primary defense against pathogens entering the body from the surface in order to prevent the start of disease and infection. Some examples of the first line of defense is the skin, protecting the external boundaries of the body, and the mucous membranes, protecting the internal boundaries of the body. Although the skin and mucous membranes work on the internal and external boundaries, they both release chemicals
3 Leicht B. G., McAllister B.F. 2014. Foundations of Biology 1411, 2nd edition. Southlake, TX: Fountainhead Press. Pp 137, 163-168, 177-180,
Thewessen, J. G. M., Williams, E. M., Roe, L. J. & Hussain, S. T. Nature 413, 277-281.
Human immunodeficiency virus (HIV) represents a major public health concern in developing and developed nations alike, with an estimated 35.3 million people worldwide living with HIV1.One-third of a century’s worth of research has helped change HIV from a steady and certain killer into a relatively manageable infection when treated with appropriate care. However, the HIV puzzle is far from solved. 2012 estimates suggest acquired immunodeficiency syndrome (AIDS, caused by HIV) kills 1.6 million each year1. Reflecting the seriousness of the pandemic, the United States National Institutes of Health has made it a research priority, investing nearly three billion US dollars in HIV/AIDS research in 2013 alone—with similar amounts budgeted for future years2.
Acquired Immune Deficiency Syndrome (AIDS) was first recognized as a new disease in 1981 when increasing numbers of young homosexual men succumbed to unusual opportunistic infections and rare malignancies (Gallant49).During this time, many people were contacting this disease because it was not discovered yet and people did not have knowledge about it.Scientists believe HIV came from a particular kind of chimpanzee in Western Africa. Humans contracted this disease when they hunted and ate infected animals. A first clue came in 1986 when a morphologically similar but antigenically distinct virus was found to cause AIDS in patients in western Africa (Goosby24). During this time, scientists had more evidence to support their claim about this disease. Once discovered this disease was identified as a cause of what has since become one of the most devastating infectious diseases to have emerged in recent history (Goosby101). This disease was deadly because it was similar to the Black Death, it was killing majority of the population. Since its first identification almost three decades ago, the pandemic form of HIV-1 has infected at least 60 million people and caused more than 25 million deaths ...
People infected with Human Immunodeficiency Virus (HIV) have a sequential destruction of CD4 T cells which always lead to a weakening of the immune system. Despite the reduction of CD4 T cells, the macrophages and dendritic cells are also affected by HIV. Moreover, HIV causes a dysfunctionality in B cells, CD8 T cells, and innate immune system cells (Shipley, 2013). For instance, the reduction of perforin production and IFN-γ secretion in CD8 T cells cannot help effector T cells to destruct virus-infected cells (Kuerten et al., 2008). The reduc...
Phelan, J. (2011). What Is Life? A Guide To Biology with Physiology. New York: Peter Marshall.
“Basic Facts about HIV/AIDS.” The Foundation for AIDS Research. N.p., n.d. Web. 8 Oct. 2012. .
... The Web. 4 Feb. 2014. Campbell, Neil A., and Jane B. Reece. Biology.
According to this quotation, without white blood cells, also known as leukocytes, we would not be able to survive. White blood cells are our body’s number one defense against infections. They help keep us clean from foreign bacteria that enter our bodies. Statistics show that there are five to ten thousand white blood cells per micro liter of blood, however this number will increase during an illness. White blood cells can differ in many ways, such as, size, shape and staining traits. There are five different kinds of white blood cells that fall into two separate categories. One category is called, granular leukocytes, and the other is called agranular white cells.
Acquired Immunodeficiency Syndrome (AIDS) first came to light in 1981. There has been a long and arduous global effort on the prevention of HIV/AIDS. HIV is a virus that is spread through body fluids that affect the specific T-cells of the immune system. Without treatment HIV infection leads to AIDS and there is no cure for AIDS. HIV infection can be controlled and the importance of primary pre...
Campbell, N. A. & J. B. Reece, 8th eds. (2008). Biology. San Francisco: Pearson Benjamin Cummings.
Most people recently infected by the AIDS virus look and feel healthy. They may not show symptoms for several years, but the condition is eventually fatal. Even though one might not know that they have this deathly disease, and remain apparently healthy, they can still pass it along to others, and they then pass it on to others, etc, until an abundant amount of people are infected. Symptoms may include fever, fatigue, weight loss, skin rashes, a fungal infection of the mouth known as thrush, lack of resistance to infection, and swollen lymph nodes. HIV, the virus that causes AIDS, is transmitted through blood, semen, and vaginal fluid. The virus is usually transferred through sexual intercourse, the transfusion of virus-contaminated blood, or the sharing of HIV-contaminated intravenous needles. HIV cannot penetrate intact bodily surfaces, such as skin, and quickly perishes outside the human body. Consequently, AIDS is not spread by casual physical contact.
Since the first cases of the Human Immunodeficiency Virus (HIV) in 1981, over 36 million people have died from the disease’s progression from HIV to Acquired Immunodeficiency Syndrome (AIDS). According to the U.S. Department of Health and Human Services, scientists generally accept that the HIV virus started in a specific type of chimpanzee in Western Africa. HIV weakens the patient’s immune system by “destroying important cells that fight disease and infection.” After HIV is acquired, progresses, and grows it turns into a much more lethal stage, AIDS. Because their immune system is heavily damaged and virtually incompetent, AIDS patients is increasingly susceptible to other infections. If medical attention is not provided for an AIDS victim, they will almost certainly die (“What Is HIV/AIDS?”). In this recent and ongoing AIDS epidemic, about 75 million people have been infected with the virus, causing 36 million deaths; but there is hope because organizations like the Samaritan’s Purse are doing their best to combat the disease.