Table 2.
Summary overview of Mtb lipid effectors.
| Name | Known release mechanism | Host target | Host cell process | Impact of gene deletion on Mtb virulence |
|---|---|---|---|---|
| PIM, LM, LAM, ManLAM | Extracellular vesicles, shedding | TLR4, TLR2-TLR1-6, MR, DC-SIGN, Dectin-2 | Cytokine response (A/I), Phagocytosis (A), phagosome maturation (I), cell death (A) | Essential, variability in acylations and LAM capping sugar moiety linked to the degree of virulence |
| TMM / TDM | Shedding | Mincle | Cytokine response (I), phagosome maturation (I) | Essential, but inability to form “cords” which is dependent on TDM attenuates the strains. |
| DAT/PAT | Extracellular vesicles, shedding | ? | Cytokine response (I), phagosome maturation (I), cell death (A) | Decreased persistence in vivo in PDIM-deficient strains, decreased growth in human macrophages. |
| PGL | Extracellular vesicles, shedding | TLR2 | Cytokine response (I) | Attenuation in vivo |
| PDIM | Shedding | ? | Cytokine responses (I) phagocytosis (A), phagosome maturation (I), phagosome escape (A), autophagy (A) apoptosis (A), necrosis (A) | Attenuation ex vivo and in vivo |
| SL-1 | Shedding | TLR-2 | Cytokine reponse (I), Phagosome maturation (I), autophagy (I), cell death (A) | No attenuation in vivo, lack of coughing and transmission in guinea pigs |
| 1-TbAd | Shedding | ? | Phagosome acidification (I) | Attenuation in human macrophages |
The parentheses behind the host cell process indicate Activation (A), Inhibition (I) or Modulation (M). If not stated explicitly the virulence impact refers to mouse studies.