Question

Topic is AIDS

1.) Describe the activity of our immune system against the pathogen

2.) What types of medical treatments exist? Describe how these treatments affect the progression of the disease.

3.) Describe prophylactic measures that can be taken to limit the risk of infection.

Answer 1

1).

Human immunodeficiency virus (HIV) is a causative agent of a dreadful sexually transmitted disease (STD) called AIDS (Acquired immunodeficiency syndrome). This virus mainly kills the T helper-cells of the immune system, thus the immune system will be malfunctioning.

HIV belongs to the genus “Lentivirus,” and family “retroviridae.” The HIV targets CD4⁺ T cells of the immune system. If the CD4⁺ T-cells count falls below 200 cells/µl, the condition is defined as AIDS (acquired immunodeficiency syndrome) though the patient presents or does not present any other symptoms.

If the CD4⁺ T-cells count falls below 400 cells/µl, the patient is likely to suffer from the opportunistic microbial infections such as tuberculosis and cancers.

The immune response against HIV:

After HIV infection, the antibodies are developed about 4 weeks later and readily attack the virions in the circulation and to some extent the HIV infected cells. As the antibodies are produced, the virus starts charging its envelope proteins (especially the mutations of gp41 and gp120) and escape from the host immune response. Due to the fast mutation rate in HIV, a wide range of antibodies are produced, but the B-cells cannot keep up with the high mutation rate and the antibody response towards the newer antigens decrease.

Humoral immunity helps to reduce the viral load. The immunoglobulin G or IgG (through complement-mediated viral infection) and natural killer cells can together with the viral growth after several days of infection.

The HIV infection reduces cytokine production, so the effect of natural killer cells against the infected cells is also less. HIV also infects the stem cells impair the process of immune cell replacement.