Cancer and AIDS Overview

Flashcards covering key vocabulary related to cancer and AIDS, specifically their definitions and important concepts discussed in the lecture.

Tumor Antigens

Substances that are displayed on the surface of cancer cells, which can trigger an immune response.

Immune System Response

The body's defense mechanism that recognizes and attacks nonself cells, such as tumor cells.

Cancer Treatment Hope

Enhancing the immune response to better attack and destroy cancer cells.

AIDS

Acquired Immune Deficiency Syndrome, caused by the HIV virus.

HIV Infection Symptoms

Initial infection produces a brief flu-like illness that typically progresses to AIDS over 2-10 years.

HIV Transmission

A person infected with HIV can spread the virus before antibodies are detectable.

T4 Cells

Cells that become helper T cells; their destruction by HIV cripples the immune system.

Opportunistic Infections in AIDS

Diseases that take advantage of a weakened immune system, often seen in AIDS patients.

Pneumocystis Carinii Pneumonia

A rare lung infection commonly seen in AIDS patients.

Kaposi's Sarcoma

A form of skin cancer often associated with AIDS.

Tuberculosis and AIDS

AIDS patients are at increased risk for developing tuberculosis.

Virus Resistance Factors

HIV is killed by bleach, Lysol, alcohol, and dried conditions.

What is the significance of the 'window period' in HIV infection?

The 'window period' refers to the time after initial HIV infection but before antibodies are detectable. During this period, an infected individual can spread the virus even though standard antibody tests may show a negative result, making early diagnosis and containment challenging.

Describe the environmental fragility of HIV outside the human body.

HIV is a fragile virus outside the human body. It is readily inactivated by common disinfectants like bleach, Lysol, and alcohol, and it cannot survive long in dried conditions, meaning it does not transmit easily through casual environmental contact.

What are the common characteristics of the acute HIV infection phase?

The acute HIV infection phase, occurring shortly after exposure, is often characterized by a brief, flu-like illness. Symptoms may include fever, fatigue, swollen lymph nodes, sore throat, and rash, as the body's immune system begins to respond to the virus.

How does the immune system generally attempt to combat the development of cancer, considering tumor antigens?

The immune system constantly surveys the body for abnormal cells. When cancer cells develop, they often display unique or altered proteins, known as tumor antigens. The immune system attempts to recognize these antigens as 'nonself' and mount an immune response to destroy the cancer cells, a process that can sometimes be overwhelmed by rapidly growing tumors.

Tumor Antigens

Substances that are displayed on the surface of cancer cells, which can trigger an immune response.

Immune System Response

The body's defense mechanism that recognizes and attacks nonself cells, such as tumor cells.

Cancer Treatment Hope

Enhancing the immune response to better attack and destroy cancer cells.

AIDS

Acquired Immune Deficiency Syndrome, caused by the HIV virus.

HIV Infection Symptoms

Initial infection produces a brief flu-like illness that typically progresses to AIDS over 2-10 years.

HIV Transmission

A person infected with HIV can spread the virus before antibodies are detectable.

T4 Cells

Cells that become helper T cells; their destruction by HIV cripples the immune system.

Opportunistic Infections in AIDS

Diseases that take advantage of a weakened immune system, often seen in AIDS patients.

Pneumocystis Carinii Pneumonia

A rare lung infection commonly seen in AIDS patients.

Kaposi's Sarcoma

A form of skin cancer often associated with AIDS.

Tuberculosis and AIDS

AIDS patients are at increased risk for developing tuberculosis.

Virus Resistance Factors

HIV is killed by bleach, Lysol, alcohol, and dried conditions.

What is the significance of the 'window period' in HIV infection?

The 'window period' refers to the time after initial HIV infection but before antibodies are detectable. During this period, an an infected individual can spread the virus even though standard antibody tests may show a negative result, making early diagnosis and containment challenging.

Describe the environmental fragility of HIV outside the human body.

HIV is a fragile virus outside the human body. It is readily inactivated by common disinfectants like bleach, Lysol, and alcohol, and it cannot survive long in dried conditions, meaning it does not transmit easily through casual environmental contact.

What are the common characteristics of the acute HIV infection phase?

The acute HIV infection phase, occurring shortly after exposure, is often characterized by a brief, flu-like illness. Symptoms may include fever, fatigue, swollen lymph nodes, sore throat, and rash, as the body's immune system begins to respond to the virus.

How does the immune system generally attempt to combat the development of cancer, considering tumor antigens?

The immune system constantly surveys the body for abnormal cells. When cancer cells develop, they often display unique or altered proteins, known as tumor antigens. The immune system attempts to recognize these antigens as 'nonself' and mount an immune response to destroy the cancer cells, a process that can sometimes be overwhelmed by rapidly growing tumors.

What is the primary cellular target of the Human Immunodeficiency Virus (HIV)?

HIV primarily targets and destroys CD4+ T lymphocytes, also known as T4 cells or helper T cells.

Explain the significance of helper T cells (T4 cells) in the immune system and why their destruction by HIV is so detrimental.

Helper T cells (T4 cells) are crucial for coordinating the immune response by activating B cells, cytotoxic T cells, and other immune cells. Their destruction by HIV cripples the entire immune system, making the body unable to fight off infections.

What is the characteristic feature of opportunistic infections seen in AIDS patients?

Opportunistic infections are caused by pathogens that typically do not cause disease in individuals with a healthy immune system but take advantage of a severely weakened immune system, such as in AIDS patients.

How can tumor antigens contribute to the development of cancer treatments?

Tumor antigens are unique or overexpressed proteins on cancer cells that can be recognized by the immune system. This allows for the development of cancer treatments, like immunotherapies, that enhance the body's own immune response to specifically target and destroy cancer cells while sparing healthy ones.

What type of virus is HIV, and what is a defining characteristic of this type of virus?

HIV is a retrovirus, meaning its genetic material is RNA, which it converts into DNA using an enzyme called reverse transcriptase to integrate into the host cell's genome.

Describe the process by which HIV infection progresses to AIDS in terms of immune cell depletion.

HIV infection progresses to AIDS as the virus continuously replicates and destroys CD4+ T lymphocytes (T4 cells). Over time, the gradual depletion of these crucial helper T cells severely compromises the immune system's ability to coordinate responses against pathogens and cancer.

What is the function of the enzyme reverse transcriptase in the HIV life cycle?

Reverse transcriptase is an enzyme unique to retroviruses like HIV. It is responsible for transcribing the viral RNA genome into a DNA copy, which then integrates into the host cell's DNA, allowing the virus to replicate.

Besides mutated proteins, what other categories of substances can act as tumor antigens?

In addition to mutated cellular proteins, tumor antigens can also include overexpressed normal proteins (found in abnormally high amounts on cancer cells) or proteins from oncogenic viruses (like HPV in cervical cancer) that are present in tumor cells.