What do foamy macrophages indicate?
Foamy macrophages are also found in diseases caused by pathogens that persist in the body, such as Chlamydia, Toxoplasma, or Mycobacterium tuberculosis. In tuberculosis (TB), bacterial lipids disable macrophages from pumping out excess LDL, causing them to turn into foam cells around the TB granulomas in the lung.
How does TB affect macrophages?
M. tuberculosis cells first clump together and ‘gang up’ on a macrophage, which engulfs the clump and dies because the bacteria overwhelm it. This does not kill the bacteria, and they rapidly grow inside the dead macrophage. The dead cell is then cleaned up by another macrophage.
Are foam cells M1 macrophages?
Interestingly, foam cells demonstrated no distinct M1 or M2 phenotype42, 43. Similarly, Chinetti-Gbaguidi et al. have localized M2 macrophages in human atherosclerotic lesions in more stable cell-rich areas of plaque away from the lipid core44.
Does TB hide in macrophages?
One reason the bacterium has survived for so long is that it has developed a sophisticated mechanism for hiding in the body: it resides in white blood cells called macrophages, the very cells that would normally kill it. Tuberculosis bacteria belong to the mycobacterial pathogens.
How macrophage foam cells develop atherosclerosis?
When inflow and esterification of cholesterol increase and/or its outflow decrease, the macrophages are ultimately transformed into lipid-laden foam cells, the prototypical cells in the atherosclerotic plaque.
How do you reduce foam cells?
Therefore, there are three major strategies to reduce foam cell formation, i.e., by 1) reducing the SR-mediated lipid uptake, 2) reducing the ACAT-mediated cholesterol esterification, and 3) promoting the transporter-mediated cholesterol efflux.
How does TB enter macrophages?
tuberculosis into macrophages can occur via an array of different receptor molecules, including complement receptors, mannose receptor, the dendritic cell-specific intercellular adhesion molecule (ICAM)-3-grabbing nonintegrin (DC-SIGN), and Fc receptors (Ernst, 1998, Cambi et al., 2005, Greenberg, 1999).
How do foam cells cause atherosclerosis?
By increasing both the internalization of oxLDL and the accumulation of lipid droplets in the macrophage, foam cell formation gradually occurs, which initially leads to fatty streaks and ultimately, to primary atherosclerotic lesions. Foam cells play a central role in the pathogenesis of atherosclerosis.
How do foam cells cause plaque?
Where does Mycobacterium tuberculosis live in the body?
Tuberculosis (TB) is an airborne bacterial infection caused by the organism Mycobacterium tuberculosis that primarily affects the lungs, although other organs and tissues may be involved.
Are foam cells good?
Foam cells are a rich source of proinflammatory mediators and there is strong evidence that support a central role for inflammation in all phases of the atherosclerotic process which includes the activation of numerous different cell types and chemoattractant agents such as proinflammatory cytokines, macrophages, and T …