Th1 stimulatory proteins of Leishmania donovani: comparative cellular and protective responses of rTriose phosphate isomerase, rProtein disulfide isomerase and rElongation factor-2 in combination with rHSP70 against visceral leishmaniasis

In visceral leishmaniasis, the recovery from the disease is always associated with the generation of Th1-type of cellular responses. Based on this, we have previously identified several Th1-stimulatory proteins of Leishmania donovani -triose phosphate isomerase (TPI), protein disulfide isomerase (PDI) and elongation factor-2 (EL-2) etc. including heat shock protein 70 (HSP70) which induced Th1-type of cellular responses in both cured Leishmania patients/hamsters. Since, HSPs, being the logical targets for vaccines aimed at augmenting cellular immunity and can be early targets in the immune response against intracellular pathogens; they could be exploited as vaccine/adjuvant to induce long-term immunity more effectively. Therefore, in this study, we checked whether HSP70 can further enhance the immunogenicity and protective responses of the above said Th1-stimulatory proteins. Since, in most of the studies, immunogenicity of HSP70 of L. donovani was assessed in native condition, herein we generated recombinant HSP70 and tested its potential to stimulate immune responses in lymphocytes of cured Leishmania infected hamsters as well as in the peripheral blood mononuclear cells (PBMCs) of cured patients of VL either individually or in combination with above mentioned recombinant proteins. rLdHSP70 alone elicited strong cellular responses along with remarkable up-regulation of IFN-γ and IL-12 cytokines and extremely lower level of IL-4 and IL-10. Among the various combinations, rLdHSP70 + rLdPDI emerged as superior one augmenting improved cellular responses followed by rLdHSP70 + rLdEL-2. These combinations were further evaluated for its protective potential wherein rLdHSP70 + rLdPDI again conferred utmost protection (∼80%) followed by rLdHSP70 + rLdEL-2 (∼75%) and generated a strong cellular immune response with significant increase in the levels of iNOS transcript as well as IFN-γ and IL-12 cytokines which was further supported by the high level of IgG2 antibody in vaccinated animals. These observations indicated that vaccine(s) based on combination of HSP70 with Th1-stimulatory protein(s) may be a viable proposition against intracellular pathogens

Leishmania donovani triose phosphate isomerase: a potential vaccine target against visceral leishmaniasis

Visceral leishmaniasis (VL) is one of the most important parasitic diseases with approximately 350 million people at risk. Due to the non availability of an ideal drug, development of a safe, effective, and affordable vaccine could be a solution for control and prevention of this disease. In this study, a potential Th1 stimulatory protein- Triose phosphate isomerase (TPI), a glycolytic enzyme, identified through proteomics from a fraction of Leishmania donovani soluble antigen ranging from 89.9–97.1 kDa, was assessed for its potential as a suitable vaccine candidate. The protein- L. donovani TPI (LdTPI) was cloned, expressed and purified which exhibited the homology of 99% with L. infantum TPI. The rLdTPI was further evaluated for its immunogenicity by lymphoproliferative response (LTT), nitric oxide (NO) production and estimation of cytokines in cured Leishmania patients/hamster. It elicited strong LTT response in cured patients as well as NO production in cured hamsters and stimulated remarkable Th1-type cellular responses including IFN-ã and IL-12 with extremely lower level of IL-10 in Leishmania-infected cured/exposed patients PBMCs in vitro. Vaccination with LdTPI-DNA construct protected naive golden hamsters from virulent L. donovani challenge unambiguously (∼90%). The vaccinated hamsters demonstrated a surge in IFN-ã, TNF-á and IL-12 levels but extreme down-regulation of IL-10 and IL-4 along with profound delayed type hypersensitivity and increased levels of Leishmania-specific IgG2 antibody. Thus, the results are suggestive of the protein having the potential of a strong candidate vaccine

Climate models predict a divergent future for the medicinal tree Boswellia serrata Roxb. in India

Predicting the distribution of future climatically suitable habitat areas is crucial for the long-term success of species conservation and management plans. However, generating accurate predictions may be difficult as the assumptions and variables used in the construction of different climate scenarios may result in divergent trajectories of change. Nevertheless, generating species distribution models under multiple scenarios is helpful in selecting an optimal solution for practical applications. In this study, we compare the current distribution of climatically suitable areas of a threatened medicinally important tree, Boswellia serrata Roxb. in India with its distribution in the year 2050 modeled using two climate change scenarios - IPSL-CM5A-LR and NIMR-HADGEM2-AO - each represented by four representative concentration pathways (RCPs). Maximum entropy modeling with 19 bioclimatic variables was used to construct the climatic niche of B. serrata for predictions of present and future climatically suitable areas within India. The study revealed that annual mean temperature, mean temperature of wettest quarter and driest quarter, precipitation seasonality, and precipitation of wettest quarter potentially influence the distribution of the species. After thresholding, the model showed that ∼21.95% of the geographical area in India is presently climatically suitable for the species. The IPSL-CM5A-LR and NIMR-HADGEM2-AO climate models revealed contrasting distribution scenarios of climatically suitable areas in India. However, irrespective of these climate models, the four RCPs predict a consistent decrease in suitable area with increases in climatic harshness. Substantial area in peninsular India is expected to lose climatic suitability in 2050, though new areas are also predicted to become climatically suitable. We suggest long-term conservation strategies for B. serrata be prioritized within future areas that are projected to retain climatic suitability

The number of tree species on Earth

One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknown. Here, based on global groundsourced data, we estimate the total tree species richness at global, continental, and biome levels. Our results indicate that there are 73,000 tree species globally, among which ∼9,000 tree species are yet to be discovered. Roughly 40% of undiscovered tree species are in South America. Moreover, almost one-third of all tree species to be discovered may be rare, with very low populations and limited spatial distribution (likely in remote tropical lowlands and mountains). These findings highlight the vulnerability of global forest biodiversity to anthropogenic changes in land use and climate, which disproportionately threaten rare species and thus, global tree richness

The number of tree species on Earth.

One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknown. Here, based on global ground-sourced data, we estimate the total tree species richness at global, continental, and biome levels. Our results indicate that there are ∼73,000 tree species globally, among which ∼9,000 tree species are yet to be discovered. Roughly 40% of undiscovered tree species are in South America. Moreover, almost one-third of all tree species to be discovered may be rare, with very low populations and limited spatial distribution (likely in remote tropical lowlands and mountains). These findings highlight the vulnerability of global forest biodiversity to anthropogenic changes in land use and climate, which disproportionately threaten rare species and thus, global tree richness

The number of tree species on Earth.

One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknown. Here, based on global ground-sourced data, we estimate the total tree species richness at global, continental, and biome levels. Our results indicate that there are ∼73,000 tree species globally, among which ∼9,000 tree species are yet to be discovered. Roughly 40% of undiscovered tree species are in South America. Moreover, almost one-third of all tree species to be discovered may be rare, with very low populations and limited spatial distribution (likely in remote tropical lowlands and mountains). These findings highlight the vulnerability of global forest biodiversity to anthropogenic changes in land use and climate, which disproportionately threaten rare species and thus, global tree richness

Foliar spraying of chlorpyrifos induces morphometric changes in Glycine max (L.) and shifts native soil microbiome

Pesticide usage alters plant growth, and development and disturbs native soil microbiome. The present study was carried out to evaluate the effect of Chlorpyrifos (CP-20% EC) on the growth and development of soybean (Glycine max), soil fertility, and soil microbiome. We conducted a pot experiment to assess the impact of different concentrations of chlorpyrifos; recommended dose (RD) and higher dose rates (2× and 4× RD). Chlorpyrifos application significantly altered the growth parameters in soybean (p < 0.05). At higher concentrations (2× and 4× RD) shoot length (17.16 ± 1.04; 14.33 ± 1.15, p < 0.05), root length (3.40 ± 0.36; 2.66 ± 0.28, p < 0.050), leaf count (6.33 ± 0.57; 2.66 ± 0.57; p < 0.05) reduced significantly compared to RD and Control groups. Similarly at these concentrations (2× and 4× RD), significant reduction in fresh shoot weight (0.86 ± 0.008; 0.66 ± 0.002, p < 0.05), dry shoot weight (0.14 ± 0.001; 0.13 ± 0.003, p < 0.05) and root fresh weight (0.13 ± 0.001; 0.09 ± 0.003, p < 0.05) and root dry weight (0.030 ± 0.0005, 0.037 ± 0.003, p < 0.05) was observed compared to the RD and control group. Notably, a significant increase in root and shoot morphometric parameters was observed in RD compared to control (p < 0.05). All the physio-chemical properties such as pH (8.51 ± 0.82), moisture content (33.73 ± 0.04), and electrical conductivity (3.44 ± 0.03) were higher in CP-treated soils compared to control. Similarly, nutrient content such as nitrogen, carbon, and hydrogen were significantly reduced in treated soils compared to control. Elemental analysis showed higher concentrations of As, Cd, and Pb in CP-treated soil (8.7 μg/g, 0.254 μg/g, and 16.477 μg/g, respectively) compared to untreated soil (8.09 μg/g, 0.228 μg/g, and 15.25 μg/g, respectively). We also assessed soil metabolic activity and diversity using Community-level Physiological Profiling (CLPP). CP-treated soil exhibited significantly lesser microbial diversity, with lesser metabolic activity. Metagenomic analysis revealed a shift in bacterial community composition, with Pseudomonadota and Bacteroidota dominating CP-treated soil, while Actinomycetota, Pseudomonadota, and Bacillota were prominent in the control group. Alpha diversity indices indicated higher abundance and species richness in the control sample compared to treatment groups. Functional analysis via PICRUSt2 identified 32 unique sub-classes of biodegrading genes in soil samples, including atzD, tfdA, argB, GLDC, gcvP, glxR, and cpdB. This suggests the potential of soil microbes for xenobiotic degradation, including pesticides. In summary, our study demonstrates that higher CP doses negatively impact soybean growth and alter soil composition, leading to reduced metabolic activity and changes in microbial communities. These findings underscore the importance of considering pesticide dosage and its ecological implications on plants, soil microbiome, and sustainable agriculture

Variation in tree biomass and carbon stocks in three tropical dry deciduous forest types of Madhya Pradesh, India

Variation in tree biomass and carbon (C) stocks in tropical dry forests is important at both regional and global scale to know their contribution in global C cycle. In Indian tropical forests, the information on variation in tree biomass and C stocks at forest type level is scarce and fragmented. In the present study, three tropical dry deciduous forest types: dry deciduous teak forest (DDTF), dry deciduous mixed forest (DDMF) and Boswellia forest (BF) have been selected in Madhya Pradesh, Central India, to assess the biomass and C stocks. The total tree biomass (aboveground + belowground) ranged from 70.4 (DDTF) to 296.6 (BF) Mg/ha with a mean of 184.1 Mg/ha, whereas the tree C ranged from 35.3 (DDTF) to 140.9 (BF) Mg C/ha with a mean value of 87.4 Mg C/ha. The greatest biomass (220.4 Mg/ha) and C stocks (104.7 Mg C/ha) have been observed in BF type, whereas the least biomass (160.9 Mg/ha) and C (76.4 Mg C/ha) have been observed in DDTF type, with the mean biomass and C stock values of 184.1 Mg/ha and 87.4 Mg C/ha, respectively. In both DDTF and DDMF types, Tectona grandis contributed 76.5 and 26.4% of C, whereas in BF type, Boswellia serrata contributed 73.6% of C to the total C stock. A significant positive (R2 = 0.951; p < 0.01) relationship has been observed between basal area and tree C stock. The present study would improve our understanding of C stocks present in these forest types and could be used to enhance the C sequestration potential through conservation, monitoring and management of such forests

Prophylactic efficacy of combinations in hamsters against <i>L. donovani</i> challenge.

<p><i>Leishmania</i> parasite burden (number. of amastigotes per 1000 cell nuclei) in the dab smears of spleen <b>(A)</b>, liver <b>(B)</b> and bone marrow <b>(C)</b> of hamsters on days 45, 60, 90, and 120 post challenge (p.c.) Since the non-vaccinated challenged (infected control) and the <i>Bacillus Calmette Guerin</i> (BCG) alone/rLdHSP70 alone vaccinated and challenged group died after day 90 (D90) of the study period, their corresponding bars are not depicted in A, B and C. Significance values indicate the difference between the vaccinated and infected group (*, p<0.05; **, p<0.01; and ***, p<0.001).</p

Sequences of forward and reverse primers of hamster cytokines used for quantitative real time PCR (qRT-PCR).

<p>Sequences of forward and reverse primers of hamster cytokines used for quantitative real time PCR (qRT-PCR).</p