Question

Morphine most probably affects the progression of HIV infection by all of the following EXCEPT: a. Changing the level of chemokine receptors. b. Changing the level of chemokines. c. Causing T-cells to undergo uncontrolled cell division. d. Mediating heterologous desensitization of chemokine receptors. e. Altering cytokine levels.

Short answer

Answer: Causing T-cells to undergo uncontrolled cell division.

Step-by-step solution

Understand how HIV infection progresses

First, let's briefly understand how HIV infection progresses. HIV targets and infects CD4+ T-cells (a type of white blood cell) and uses them to replicate. CD4+ T-cells play a crucial role in the immune system's response to infection. HIV enters CD4+ T-cells by binding to their surface molecule called CD4 along with a chemokine receptor, such as CXCR4 or CCR5. Chemokines are signaling molecules that attract immune cells to the site of infection to help mount a response.

Examine the effects of morphine on the progression of HIV infection

Morphine is a powerful pain reliever and has several immunomodulatory effects that can influence the progression of HIV infection. Let's go through the given options: a. Changing the level of chemokine receptors: Morphine is known to modulate the expression of chemokine receptors on the cell surface, which can facilitate HIV entry into the CD4+ T-cells. b. Changing the level of chemokines: Morphine can also alter the release of chemokines, affecting the immune response and allowing the virus to infect more cells. d. Mediating heterologous desensitization of chemokine receptors: Morphine can downregulate the function of chemokine receptors through a process called heterologous desensitization, weakening the immune response. e. Altering cytokine levels: Morphine can modulate the levels of cytokines (cell-signaling proteins), which are critical in regulating the immune response against infection, indirectly impacting the course of HIV infection.

Identify the option that does NOT affect HIV progression by morphine

Now that we have reviewed the effects of morphine on the progression of HIV infection, we can rule out options a, b, d, and e. The remaining option, c, states that morphine causes T-cells to undergo uncontrolled cell division. This statement is false, as there is no evidence to suggest that morphine directly or indirectly induces uncontrolled cell division in T-cells. Instead, HIV itself leads to immune dysfunction and could eventually result in the death of the CD4+ T-cells. Hence, the answer is: c. Causing T-cells to undergo uncontrolled cell division (this is the option that does NOT affect the progression of HIV infection by morphine).