Anti-M. tuberculosis Polyclonal antibody

Mycobacterium tuberculosis possesses the ability to undergo physiological adaptations in order to persist during the prolonged course of infection despite the active immune response of the host and in order to overcome multiple environmental changes. Previous studies have proposed that M. tuberculosis CuvA (Rv1422; MtCuvA) might play a critical role in the adaptation of the bacterium to environmental changes, such as nutrient utilization and alteration of the growth rate. However, the detailed function of MtCuvA still remains unclear owing to a lack of structural information. To better understand its role in host adaptation, MtCuvA was purified to homogeneity and was crystallized for the first time using the hanging-drop vapor-diffusion method. The crystal of MtCuvA diffracted to a resolution of 2.1 angstrom and belonged to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 47.27, b = 170.93, c = 178.10 angstrom. The calculated Matthews coefficient (V-M) was 2.4 angstrom(3) Da(-1), with a solvent content of 48.02%, and thus four molecules appeared to be present in the asymmetric unit. Moreover, it is reported that MtCuvA can bind to the cell-wall precursor components uridine diphosphate (UDP)-glucose and UDP-N-acetyl-glucosamine.

MPT64 is a 24-kDa immunogenic protein that is widely used as a diagnostic marker for the differentiation of Mycobacterium tuberculosis complex (MTBC) from nontuberculous Mycobacterium (NTM). Unlike Mycobacterium bovis, Bacillus Calmette-Guerin(BCG) vaccine strains with RD2 deletion do not secrete MPT64. Culture isolates from infections due to these strains may be falsely identified as nontuberculous Mycobacterium in the absence of clinical correlation. Here, we present one case each of BCG adenitis and osteitis, both of which were considered as MPT64 card-negative Mycobacterium spp. (i.e., NTM) and were later identified as M. bovis BCG Danish 1331 strain. The first case was a 4-month-old female infant admitted with swollen lymph nodes in the left supraclavicular and the left axillary region of 1 month duration. The second case was of a 1-year-and-5-month-old male child who presented with a limp on the left leg and soft tissue swelling of 1 month duration on the anterolateral aspect of the left knee joint. In both cases, BCG vaccine was administered at birth on the left deltoid region and had healed without any complication. Clinical samples in both cases were positive by Xpert tuberculosis/RIF for MTBC, and cultures grew acid-fast bacilli which were negative by MPT64 assay. The clinical implication of infections due to M. bovis BCG is immense as they are inherently resistant to pyrazinamide, and the presence of disseminated BCG infection in young children is a hallmark of serious immune deficiency which needs to be ruled out.