Abstract
The human immunodeficiency virus, HIV, is a non-cellular form of organization, showing the properties of living systems when penetrating the body. The virus has a spherical structure: inside the shell, there are two strands of RNA and enzymes. By joining the CD4 receptors of T-lymphocytes, HIV injects its genome into the host’s DNA, which provokes the synthesis of new viral particles. The virus produces a progressive infection that actively suppresses immunity: if a patient does not take therapy, they will develop AIDS.
Resume
The approved article discusses the morphology, genomics, clinic, and pathophysiology of HIV. The information includes detailed information about the molecular structure of the virus, the form of the genome, and the mechanism of self-reproduction within a targeting cell (German Advisory Committee Blood, 2016). Moreover, the article discusses the clinical manifestations of infection and symptoms and offers several solutions to save a patient’s life. It also describes antiretroviral therapy and provides a list of medications. The authors of the article show the virus’s epidemiology, routes of transmission, and known cases of complete cure.
Classification of Microorganism
Taking into account the peculiarity of the pathogen, which was selected and approved for the task, this paragraph is not quite correct to name the classification of microorganisms because the Human Immunodeficiency Virus, HIV, is not an organism. Traditional biology systematically classifies viruses, including HIV, as transitional forms of life organization, since outside the host organism, the virus cannot grow and multiply independently, staying in anabiotic form. However, as soon as the virus gets into the cell, it triggers self-reproduction mechanisms and shows signs of living one. Among the large variety of subgroups of viruses, HIV belongs to the retrovirus type (Retroviridae), which has RNA as genetic material and affects mostly vertebrates. Furthermore, the unique ability to deliver large amounts of RNA to the target cell and the capacity to activate replication in envisioned cells determine whether HIV belongs to the lentivirus genus that has a long incubation period.
Structural Characteristics
The morphological structure of HIV resembles a sphere with an effective diameter of about 100-120 nanometers. This form of the virus is caused by a two-layer phospholipid shell with 72 glycoprotein (Env) complexes on its surface that actively bind to CD4-receptors of human cells T-lymphocytes. Inside the envelope, the virus has a protein capsid with a cylindrical or cone-like structure that contains central molecules. Thus, in the core of HIV, there are two single-stranded RNA fibers, internal proteins, the enzymes of reverse transcriptase and endonuclease, which allow for cutting the DNA of the host cell. It should be noted that the virus genome is represented by 9200-9600 nucleotides, with the ends of the genome represented by long repetitions controlling the synthesis of new viral particles.
Susceptibility to Antiviral
Although HIV shows resistance to antibiotics due to the viral origin of the particle, it is susceptible to destruction by certain antiviral drugs, on which the therapy for HIV-positive patients is based. Antiretroviral therapy significantly slows down disease progression by preventing viral replication and thus reducing the concentration of viral RNA in the patient’s blood. The specific mechanisms of the drugs’ action are reduced to inhibiting the activity of reverse transcriptase (Abacavir, Tenofovir), destroying the viral protease (Amprenavir), and preventing the effective connection of glycoprotein virus growths with CD4 lymphocyte receptors (Dolutegravir, Enfuvirtide).
Growth Conditions
Perhaps, the central growth factors for HIV are the presence of T-lymphocytes in the body and the ability to bind to cell CD4-receptors actively. Without these components, a virus particle, even if penetrated into the body, dies under the influence of immunity and biological enzymatic fluids. It should be understood that as soon as new virus particles have matured inside an infected cell, they break out into the bloodstream, where they have only a few hours to infect new cells. At this stage, the immune response of the body plays a decisive role in the development of the virus: if macrophages and lymphocytes cannot provide adequate protection, then HIV infects most blood cells in different organs. Under laboratory conditions, the virus dies almost instantly by boiling, in a highly concentrated water-alcoholic essence, or by disinfectants. The acceptable ambient temperature at which the virus can still survive outside the body should not exceed 39 degrees Fahrenheit, which explains the rapid death of particles at room temperature.
Evasion of Immune System
Once in the body, HIV passes through many physiological barriers before penetrating into the blood. Herein, HIV is attached to the surface of a CD4+ T-lymphatic cell using receptors and co-receptors located on the cell surface. The virus must securely attach itself to the receptor and the co-receptor in order to penetrate the cell through the membrane. After penetration, HIV injects its protein “nucleus” into the cell with two single chains of viral RNA: the reverse transcriptase creates a DNA version of the virus genome, forming a double helix, which is then embedded in the genome cell. During protein biosynthesis, ribosomes transmit the formation of protein capsules from which new virus particles are collected.
Disease
HIV infection is a progressive disease characterized by a gradual decrease in human immunity. In the final stages, when the host’s macrophages and lymphocytes have no power against foreign agents, AIDS begins. Symptoms of the disease include weight loss and the development of opportunistic diseases: meningitis, tuberculosis, pneumonia, or Kaposi sarcoma. Therapy involves constant monitoring of immune status, prevention, and treatment of secondary infections and neoplasm development control. The disease is incurable, although antiretroviral therapy can help curb the development of HIV.
Reference
German Advisory Committee Blood. (2016). Human Immunodeficiency Virus (HIV)[PDF document]. Web.