Table 4.

Set of 10 signature genes with their role in TB, lung disease or inflammatory processes

Gene symbol	Gene name	Function	Possible role in TB, lung disease or inflammatory processes
CHRM2	Cholinergic muscarine 2 receptor	cAMP regulation on airway smooth muscle.	· Loss of muscarine receptor function is associated with airway hyperreactivity [12].
AMPH	Amphiphysin	Phagocytosis, clathrin-mediated endocytosis in alveolar macrophages [13].	· Clathrin-mediated endocytosis in the lungs plays an important role in mediating the internalization of human rhinovirus and influenza A virus [14,15].
			· Inhibition of clathrin-mediated endocytosis led to inhibition of lipopolysaccharide (LPS) internalization and cytokine/chemokine release from macrophages stimulated by LPS [16].
SNX17	Sorting nexin 17	Intracellular binding protein for the adhesion molecule P-selectin [17].	· P-selectin is important in the early phase of cell migration in TB infection and increased P-selectin serum levels are found in TB patients [18].
PIGC	Phosphatidylinositol glycan anchor biosynthesis class C	Biosynthesis of glycosylphosphatidylinositol [19].	· Incorporation of the mycobacterial cell wall component lipoarabinomannan (LAM) into the macrophage cell membrane, a process that is dependent on successful insertion of a glycosylphosphatidylinositol anchor, is one of the key virulence factors for M. tuberculosis[20].
S100P	S100 calcium binding protein P	Calcium-binding protein involved in intracellular and extracellular calcium sensing and signal transduction [21].	· M. tuberculosis-mediated inhibition of a cytosolic rise in calcium is one of the essential steps in phagosome maturation [22].
TAS2R46	Taste receptor type 2 member 46	Regulation of ciliary beat frequency through modulation of intracellular calcium concentration [23].	· M. tuberculosis-mediated inhibition of a cytosolic rise in calcium is one of the essential steps in phagosome maturation [22]. Decreased expression of TAS2R receptors has been shown to lead to a decrease in intracellular calcium concentration [23].
			· TAS2Rs are expressed on human airway smooth muscle where they cause bronchodilation through a localized calcium response [24].
STYXL1	Serine/threonine/tyrosine interacting-like1	Inhibition of formation of stress granules.	· Stress granules are host RNA cytoplasmic granules formed in response to infections by a pathway involving phosphorylation of the translation initiation factor eIF2α [25].
HBD	Hemoglobin delta	Encodes for the delta globin chain of HbA2.	· Involved in oxygen transport from the lung to the peripheral tissues.
GLDC	Glycine dehydrogenase (decarboxylating)	Metabolic enzyme promoting cellular transformation.	· Altered GLDC expression has been correlated with survival time in lung cancer patients [26].
ACOT7	Acyl-CoA thioesterase 7	Expressed in macrophages, plays a role in inflammation through production of arachidonic acid.	· The molecular and cellular functions of ACOT7 have identified the enzyme as a candidate drug target in inflammatory diseases [27].