Activation of anti-tumor immune response and reduction of regulatory T cells with Mycobacterium indicus pranii (MIP) therapy in tumor bearing mice

Background

Role of immune system in protecting the host from cancer is well established. Growing cancer however subverts immune response towards Th2 type and escape from antitumor mechanism of the host. Activation of both innate and Th1 type response is crucial for host antitumor activity. In our previous study it was found, that Mycobacterium indicus pranii (MIP) also known as M. w induces Th1 type response and activates macrophages in animal model of tuberculosis. Hence, we studied the immunotherapeutic potential of MIP in mouse tumor model and the underlying mechanisms for its antitumor activity.

Methodology and Principal Findings

Tumors were implanted by injecting B16F10 melanoma cells subcutaneously into C57BL/6 mice. Using the optimized dose and treatment regimes, anti-tumor efficacy of heat killed MIP was evaluated. In MIP treated group, tumor appeared in only 50–60% of mice, tumor growth was delayed and tumor volume was less as compared to control. MIP mediated immune activation was analysed in the tumor microenvironment, tumor draining lymph node and spleen. Induction of Th1 response and higher infiltration of immune cells in the tumor microenvironment was observed in MIP treated mice. A large fraction of these immune cells were in activated state as confirmed by phenotypic and functional analysis. Interestingly, percentage of Treg cells in the tumor milieu of treated mice was less. We also evaluated efficacy of MIP along with chemotherapy and found a better response as compared to chemotherapy alone.

Conclusion

MIP therapy is effective in protecting mice from tumor. It activates the immune cells, increases their infiltration in tumor, and abrogates tumor mediated immune suppression.     

Effect of dihydroergotoxine, a cerebral vasodilator, on cognitive deficits induced by prenatal undernutrition and environmental impoverishment in young rats

The study was conducted on 64 Charles Foster strain albino rats, which were equally distributed into 8 evenly matched groups, following a 2 x 2 x 2 factorial design, by varying three independent factors at two levels: nutrition--normal and undernutrition; environment--enrichment and impoverishment, and drug treatment--vehicle and dihydroergotoxine (3 mg/kg, i.p.). Prenatal undernutrition was induced by restricting the mother's food intake. The environmental enrichment/impoverishment and the vehicle/dihydroergotoxine treatments were given during the postweaning period of the pups. The rats were subjected to original and subsequent reversal brightness discrimination learning tests in a single unit T-maze at 8-9 weeks of age. Thereafter, the animals were tested for passive avoidance learning. The results indicate that undernutrition caused significant original and reversal discrimination learning, deficits whereas environmental deprivation attenuated only the original discrimination learning performance. Dihydroergotoxine treatment facilitated the learning performance of rats in both the original and reversal learning tests. Nutritional, environmental and dihydroergotoxine treatments had no effect on the retention of the passive avoidance learning, both at 24 hr and 1 week intervals. Dihydroergotoxine treatment attenuated the learning deficits induced by prenatal undernutrition. The results indicate that dihydroergotoxine is not likely to be useful in cognitive deficits, induced by malnutrition, though it facilitated learning acquisition, since it had no effect on retention.     

Improved gossip protocol for blockchain applications

Cluster Computing - Blockchain is a distributed digital ledger consisting of sequence of blocks. These blocks are groups of transactions that make up a sequence where each block contains the...     

Gadd45alpha does not modulate the carboplatin or 5-fluorouracil-induced apoptosis in human papillomavirus-positive cells

Gadd45alpha is shown to be induced by a wide spectrum of DNA-damaging agents and implicated in negative regulation of cell growth by causing G2-M arrest or induction of apoptosis. In the present study, we explored the involvement of p53 in the promoter activation of Gadd45alpha as well as the role of Gadd45alpha in carboplatin (Carb) or 5-fluorouracil (5-FU)-induced apoptosis in human papillomavirus virus (HPV)-positive HEp-2 and HeLa cells. We report that Carb or 5-FU upregulate Gadd45alpha and p53 in both these cells. Transient transfection of chloramphenicol acetyl transferase (CAT)-reporter construct driven by Gadd45alpha promoter clearly indicated that Gadd45alpha upregulation was mediated through activation of its promoter. Inhibition of p53 function by dominant-negative-p53 expression partially suppressed the activation of Gadd45alpha promoter. Further, the induction of apoptosis was assessed by detection of poly (ADP-ribose) polymerase (PARP) cleavage by Western blot analysis. Inhibition of upregulated Gadd45alpha expression by antisense expression vector did not modulate the Carb or 5-FU-induced apoptosis. Overall, we conclude that Gadd45alpha promoter activation partially depends on p53 function in HPV-positive cells. Moreover, Gadd45alpha protein does not modulate Carb or 5-FU-induced apoptosis in these cells.     

Recombinant infectious bursal disease virus carrying hepatitis C virus epitopes

The delivery of foreign epitopes by a replicating nonpathogenic avian infectious bursal disease virus (IBDV) was explored. The aim of the study was to identify regions in the IBDV genome that are amenable to the introduction of a sequence encoding a foreign peptide. By using a cDNA-based reverse genetics system, insertions or substitutions of sequences encoding epitope tags (FLAG, c-Myc, or hepatitis C virus epitopes) were engineered in the open reading frames of a nonstructural protein (VP5) and the capsid protein (VP2). Attempts were also made to generate recombinant IBDV that displayed foreign epitopes in the exposed loops (P(BC) and P(HI)) of the VP2 trimer. We successfully recovered recombinant IBDVs expressing c-Myc and two different virus-neutralizing epitopes of human hepatitis C virus (HCV) envelope glycoprotein E in the VP5 region. Western blot analyses with anti-c-Myc and anti-HCV antibodies provided positive identification of both the c-Myc and HCV epitopes that were fused to the N terminus of VP5. Genetic analysis showed that the recombinants carrying the c-Myc/HCV epitopes maintained the foreign gene sequences and were stable after several passages in Vero and 293T cells. This is the first report describing efficient expression of foreign peptides from a replication-competent IBDV and demonstrates the potential of this virus as a vector.     

Plant growth promotion and suppression of charcoal‐rot fungus (Macrophomina phaseolina) in velvet bean (Mucuna pruriens L.) by root nodule bacteria

Root‐nodulating bacteria are intimate associates of legumes. From a pool of rhizobia isolated from root nodules of Mucuna pruriens (Velvet bean/Kaunch), RMP66 and BMP17 were found to be capable of promoting siderophore and IAA production and phosphate solubilization (insoluble tri‐calcium). Both symbionts were studied further to determine their abilities to promote plant growth and to control root‐rot in Mucuna pruriens caused by the pathogenic plant fungus Macrophomina phaseolina. RMP66 and BMP17 were selected based on their excellent inhibitory activities against M. phaseolina (by 78% and 71%, respectively) in dual culture and in agar‐well assays using cell‐free culture filtrate (CFCF) (by 76% and 62%, respectively). Both strains inhibited fungal growth to a greater extent in iron‐deficient medium (51% and 69%) than in iron‐supplemented medium (37% and 0%), respectively. CFCFs of RMP66 and BMP17 obtained from Pikovskaya's broth and tryptophan‐amended YEM broth inhibited fungal growth by 80%‐55% and 70%‐43%, respectively, and were identified as Sinorhizobium meliloti RMP66 and Bradyrhizobium diazoefficiens BMP17 by 16S rDNA sequencing. Centrifuged and pelleted cells harvested from exponentially grown cultures of S. meliloti RMP66 and B. diazoefficiens BMP17 were used to bacterize seeds of M. pruriens, which then showed enhanced seed germination (by up to 17% and 12%, respectively), and subsequent increases in other plant growth parameters in field trials. Considerable increases in seedling vigour indices (62%: 53% and 110%: 130%) and biomass (8%: 13% and 25%: 28%) were also observed for bacterial treatments. Tn5‐mediated antibiotic‐resistant marker strains showed enhanced nodule occupancy by up to 72% and 68%, respectively. This study describes a multifunctional legume nodule rhizobia that could be utilized in multicropping systems under different agroclimatic conditions as a bioinoculant and alternative to fertilizers.     

Phosphorylation of Mycobacterium tuberculosis Ser/Thr phosphatase by PknA and PknB

Background

The integrated functions of 11 Ser/Thr protein kinases (STPKs) and one phosphatase manipulate the phosphorylation levels of critical proteins in Mycobacterium tuberculosis. In this study, we show that the lone Ser/Thr phosphatase (PstP) is regulated through phosphorylation by STPKs.

Principal Findings

PstP is phosphorylated by PknA and PknB and phosphorylation is influenced by the presence of Zn²⁺-ions and inorganic phosphate (Pi). PstP is differentially phosphorylated on the cytosolic domain with Thr¹³⁷, Thr¹⁴¹, Thr¹⁷⁴ and Thr²⁹⁰ being the target residues of PknB while Thr¹³⁷ and Thr¹⁷⁴ are phosphorylated by PknA. The Mn²⁺-ion binding residues Asp³⁸ and Asp²²⁹ are critical for the optimal activity of PstP and substitution of these residues affects its phosphorylation status. Native PstP and its phosphatase deficient mutant PstP_c ^D38G are phosphorylated by PknA and PknB in E. coli and addition of Zn²⁺/Pi in the culture conditions affect the phosphorylation level of PstP. Interestingly, the phosphorylated phosphatase is more active than its unphosphorylated equivalent.

Conclusions and Significance

This study establishes the novel mechanisms for regulation of mycobacterial Ser/Thr phosphatase. The results indicate that STPKs and PstP may regulate the signaling through mutually dependent mechanisms. Consequently, PstP phosphorylation may play a critical role in regulating its own activity. Since, the equilibrium between phosphorylated and non-phosphorylated states of mycobacterial proteins is still unexplained, understanding the regulation of PstP may help in deciphering the signal transduction pathways mediated by STPKs and the reversibility of the phenomena.     

Role of alpha-melanocyte stimulating hormone (α-MSH) in modulating the molecular mechanism adopted by melanocytes of Bos indicus under UVR stress

Molecular and Cellular Biochemistry - Ultraviolet radiations (UVR) are responsible for a wide variety of acute and chronic effects on the animal skin. However, the effect of UVR-induced oxidative...