Reduced erythrocyte CR1 levels in patients with pulmonary tuberculosis is an acquired phenomenon

Major histocompatibility complex class III (C2, C4, factor B) and C3 gene variants in patients with pulmonary tuberculosis

“…Our recent studies on pulmonary TB (PTB) showed an association of Q to H substitution at the 1022 position in the complement receptor 1 (CR1) gene, a membrane-associated complement component, particularly the HH genotype, with susceptibility to this infection [23]. Another study carried out in an African population has reported a similar association between the homozygous HH genotype of the CR1 with susceptibility to TB [24].…”

“…Patients and HC were of same ethnic origin belonging to Dravidian descent of south Indian population living in and around Chennai, Tamil Nadu, and constitute the same cohort as reported earlier [23].…”

Dynamic control of the complement system by modulated expression of regulatory proteins

“…Erythrocyte CR1 is decreased in several diseases associated with high levels of circulating immune complexes, including systemic lupus erythematosus (63), rheumatoid arthritis (64), and pulmonary tuberculosis (65). Decreased CR1 may be due to consumption of the protein during immune-complex clearance.…”

The role of variants from the innate immune system genes in tuberculosis and skin test response in a Native American population

“…Apparently, a lower affinity between CR1 and C3 confers a poor immune response against Mtb, leading to higher susceptibility to the disease and higher anergy rates. Senbagavalli et al [22] observed reduced levels of CR1 in patients with TB, speculating that they were due to the greater bacillary load. This load leads to more immune complexes formation demanding the engagement of CR1 molecules, which are subsequently lost in the process of immune complexes elimination.…”