The AIDS Beacon™

Below is a list of terms and definitions relating to HIV/AIDS:

A B C D E F G H I J K L M N O P Q R S T U V W X Y

A

ART (Antiretroviral Therapy)
The use of antiretroviral drugs to suppress infection by retroviruses, mainly HIV. ART consists of at least three antiretroviral drugs taken together to stop the progression of HIV infection.

C

Cardiovascular
The system in the body that distributes blood.

CD4 cells
A subset of T cells, a type of white blood cells, known as helper T cells. These helper T cells are called CD4 cells because their cell surfaces express the CD4 protein. HIV infects and kills CD4 cells, which leads to a weakened immune system.

CD4 cell count
A measurement of the number of CD4 cells in one cubic millimeter of blood. As a type of white blood cell, the CD4 cell helps fight infections in the body. Therefore, the CD4 cell count is an essential measure of the health of a person’s immune system.

Cholesterol
A waxy, fat-like substance needed for important bodily functions, such as the formation of cell membranes and certain hormones.

Combination therapy
Taking two or more antiretroviral drugs at a time. This helps reduce the chances that HIV will become resistant to just one drug, making antiretroviral therapy more effective.

Conjunctivitis
An eye infection that is commonly referred to as “pink eye”. It can be caused by a virus or bacteria, and symptoms and treatments depend on the infecting agent.

Back to top

D

DNA
The double-stranded genetic material that stores all of the information that is required to develop and sustain life.

G

Glucose
A molecule that serves as the building blocks for different kinds of sugar.

H

HAART (Highly Active Antiretroviral Therapy)
Combination of at least three antiretroviral drugs to maximally suppress HIV infection.

Herpes simplex virus-2
A virus that is transmitted through unprotected sexual or oral contact. The virus is often in a latent, or inactive stage, but causes painful sores when in an active stage. There is no cure for this infection, and HSV-2 infected individuals are at a higher risk for acquiring HIV when practicing unprotected sex with HIV positive persons.

Hormone
A chemical secreted by cells to affect other cells. They can inhibit or activate the immune system or metabolism, for example.

Back to top

I

Inflammatory response
The inflammatory response is the body’s defense mechanism against infection. During the inflammatory response, individuals may experience pain, redness, and swelling at the site of infection.

Integrase inhibitors
A class of antiretroviral drugs that block the action of the enzyme integrase. Integrase helps integrate viral DNA into the DNA of the host CD4 cell. By stopping this action, integrase inhibitors prevent the healthy host cells from becoming infected with HIV’s DNA, thereby stopping HIV from replicating.

L

Lipid
A broad group of naturally-occurring molecules which includes fats, waxes, cholesterol, and vitamins A, D, E and K. They function as signaling molecules, structural components of cell membranes, and as energy storage.

Lipodystrophy
Disorder that causes a redistribution of fat in the body. There are two types:

• Lipoatrophy: Loss of fat in areas such as the arms, legs, and face.
• Lipohypertrophy: Buildup of fat in areas such as the stomach, shoulders, back of the neck, and breasts.

Lymphoid
Refers to the lymphatic system, a network that circulates fluid called lymph to various organs that produce and organize lymphocytes, cells important in the immune system. These organs include lymph nodes, bone marrow, the thymus, and the spleen.

Back to top

M

Macrophage
A white blood cell of the immune system that specializes in engulfing invading organisms. Macrophages internalize and kill their “prey” by using their own enzymes to break down the cells of the invader.

N

Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
A class of anti-HIV medications. In order to replicate, HIV must convert its RNA into DNA, which is accomplished with the aid of the reverse transcriptase enzyme. NNRTIs attach themselves to this enzyme, which prevents it from converting viral RNA into DNA. Thus, viral replication does not occur.

Nucleoside reverse transcriptase inhibitors (NRTIs)
A category of anti-HIV medications. When replicating, HIV must convert its RNA into DNA, which is accomplished with the aid of the reverse transcriptase enzyme. NRTIs serve as fake versions of the chemicals that reverse transcriptase needs to function, thus preventing the formation of viral DNA.

Back to top

O

Opportunistic infections (OIs)
Infections that occur in people with weakened immune systems that do not normally occur in healthy individuals, including people with HIV/AIDS.

P

Parasite
A general term used to describe organisms that rely on organisms of a different species to survive. Parasites do not provide any benefit to their host. Parasites can be microscopic, such as viruses, or can be as large as leeches.

PEP (Post-exposure prophylaxis)
A preventative treatment given immediately after a high-risk exposure to HIV. This treatment is given in hopes of preventing the development of HIV infection. Most commonly, it is used for people who are exposed to HIV in occupational settings.

Protease inhibitors (PIs)
A class of antiretroviral drugs that block the action of the enzyme protease. The protease enzyme cleaves protein chains into smaller fragments, which are later assembled to make functional viruses. Protease inhibitors prevent this slicing action, thereby inhibiting the further production of viruses.

Back to top

R

Reverse transcriptase (RT)
An enzyme used by viruses to transcribe, or convert, viral RNA into DNA. This viral DNA is then inserted into the DNA of the host cell, allowing the cell to produce new viruses.

RNA
The single-stranded genetic material that is copied from DNA to make proteins.

S

Serodiscordant
Describes a couple in which one partner is HIV positive and the other partner is HIV negative.

Strain
The unique genetic variant or subtype of HIV that has distinct characteristics.

Back to top

T

T cells
A type of white blood cell known as lymphocytes. T cells are part of the body’s immune system response. There are several types of T cells, including CD4 cells.

Transmission
The ability of a pathogenic, or disease-causing organism, to spread between different hosts.

Triglycerides
A form of fat found in the blood plasma that is used for energy.

V

Viral load
The amount of HIV virus present in the blood stream, measured as the number of HIV copies in one milliliter of blood.

Viral replication
The process by which viruses make copies of themselves. The HIV virus replicates by first infecting CD4 cells and subsequently taking charge of the cell’s functions. After infection, HIV uses the CD4 cell as a type of “factory” for manufacturing new viruses. These viruses mature and burst out of the CD4 cell, and proceed to infect other healthy CD4 cells to continue the cycle of replication.

Back to top