Basic and Clinical Sciences (BCSE) Practice Exam

Silica dust has been shown to have a detrimental effect on the immune response, particularly in the context of tuberculosis (TB). When silica is inhaled, it leads to the activation of immune cells, including macrophages, which are crucial for combating infections like TB. However, silica dust can impair the function of these macrophages, reducing their ability to phagocytize pathogens and effectively respond to the intracellular bacteria that cause tuberculosis. This inhibition compromises the immune response, making individuals more susceptible to TB infections or exacerbating existing infections.

In contrast, the other options suggest responses that either do not accurately describe the effect of silica dust or imply a support of immune function that is not consistent with its known impact. For example, while increased production of antibodies or enhanced macrophage activity would generally be considered beneficial in the context of fighting infections, silica dust does not facilitate such responses; instead, it weakens the innate immune defense. Likewise, stimulating T-cell proliferation would indicate an improvement in immune response, which does not align with the inhibitory effects silica has on macrophage function in the context of tuberculosis.