Potential of adjunctive Mycobacterium w (MIP) immunotherapy in reducing the duration of standard chemotherapy against tuberculosis

INTRODUCTION

The need to shorten the treatment duration in tuberculosis has always been felt. Immunotherapy in combination with chemotherapy has been considered a promising approach for this purpose into tuberculosis. We studied the adjuvant immunotherapeutic activity of Mycobacterium indicus pranii (MIP or Mw) in combination with conventional chemotherapy using guinea pig of pulmonary tuberculosis infected with Mycobacterium tuberculosis H37Rv via aerosol.

METHODS

Experimental animals treated with standard chemotherapy and immunotherapy (MIP) separately and in combination of both. Guinea pig lungs evaluated following infection and subsequent therapy at predefine time point. Various cytokine mRNA expressions levels were quantified by quantitative reverse transcriptase PCR at the 4th, 8th and 12th week post-infection of M. tuberculosis.

RESULTS

We determined the time required for bacterial clearance from guinea pig lungs. Standard chemotherapy (RvCh) compared to the animals where chemotherapy plus Mw immunotherpay (RvChMwT) was given. It took 12 weeks to achieve bacterial clearance in the RvCh group while this was achieved in 8 weeks in RvChMwT group. Pro-inflammatory cytokines (IFN-γ, IL-2, IL-12p35 and TNF-α) level were higher in RvCh, RvChMwT and RvMwT group, while the IL-10 and TGF-β were suppressed.

CONCLUSION

Cytokine expression level showed that Mw in conjunction with chemotherapy enhances the effect of pro-inflammatory cytokines (such as, IFN-γ, IL-2, IL-12 and TNF-α) and reduces the production and effect of anti-inflammatory cytokines (like IL-10 and TGF-β) thereby restoring the pro-inflammatory / anti-inflammatory cytokines balance. Thus, the present study indicates that subject to rigorous testing by other parameters, Mw (MIP) as adjunct immunotherapy has potential for reducing treatment duration.

Expression profile of CXCL12 chemokine during M. tuberculosis infection with different therapeutic interventions in guinea pig

Mycobacterium indicus pranii (MIP) already established as an immune-modulator in mycobacterial infections generates immune response by acting on CXC chemokines. In the present study, the immunomodulatory effect of MIP in conjunction with chemotherapy against M.tb infection was evaluated by colony forming units (CFUs) following aerosol infection to guinea pig and by measuring CXCL12 chemokine expression using q-PCR and in situ RT-PCR. Different experimental groups included, infection (Rv), immunoprophylaxis (RvMw), chemotherapy (RvCh) and combination of immunoprophylaxis+chemotherapy (RvChMw) group and normal healthy (NH) group. In the combination of immunoprophylaxis+chemotherapy (RvChMw) group, the CFU counts reduced significantly (p<0.001) at 4th week of infection as compared to other treated groups (RvMw and RvCh group). The expression of CXCL12 was recorded in all the treated groups of animals. The study demonstrated suppressed expression of CXCL 12 in both immunoprophylaxis as well as chemotherapy groups (6th and 8th week) that become elevated in immunoprophylaxis plus chemotherapy group (10th week), at which time point no CFUs were detected in RvCh and RvChMw group. The findings indicate that the expression of CXCL12 is associated with good response to anti - tubercular treatment. Thus, prior immunization with MIP appears to show good immunomodulatory effect to release CXCL12 chemokine during infection and also correlates with enhanced effect to chemotherapy.

'Bio-load' and bio-type profiles of Mycobacterium avium subspecies paratuberculosis infection in the domestic livestock population endemic for Johne's disease: a survey of 28 years (1985-2013) in India

Bio-load and bio-profile of Mycobacterium avium subspecies paratuberculosis was studied in the domestic livestock population of the country. Of the 23,429 farm and farmer's animals screened, average bio-load was 23.3% (Period of study; 28 years for goats; 13 years for sheep, cattle and buffaloes). Species-wise, bio-load was 20.1, 32.7, 39.3 and 28.3% in goats, sheep, cattle and buffaloes, respectively. Bio-load was significantly lower in time period A (P < 0.001) and B (P < 0.03), compared with period C. Geographical zone-wise, bio-load of MAP was significantly higher (P < 0.05) in Central zone compared with South, West, East and North zones. Bio-load in 11 states ranged from 16.2 to 87.8%. Of 8450, 5643, 8185 and 1151 samples screened by microscopy, culture, indigenous ELISA and IS900 blood PCR, 20.0, 10.6, 35.1 and 26.6% samples were positive, respectively. Bio-load was 32.8 and 31.6% in farm and farmer's goats and sheep, respectively, and 62.1% in farmer's cattle. MAP bio-load was also monitored in four farm units (three goats and one sheep) for breed improvement and three farm goats units for experimental purposes at Central Institute for Research on Goats in Mathura district. Of the 8025 goats and 1525 sheep that died from 1988 to 2013, 10.9 and 3.0% deaths were due to JD, respectively. On the basis of JD and suspected JD, 10.0 and 28.4% goats and 2.2 and 40.9% sheep, respectively were culled from the farm units in 25 years. Microscopic examination of 214 tissues (mesenteric lymph nodes and intestines) of 107 animals, it was observed that bio-load of MAP was high (25.0-60.0%) in farm animals. 'Indian Bison Type' was the dominant biotype, irrespective of domestic livestock species and the geographical zone.