Role of MHC antigens and Immunoregulation in Graft Survival in autoimmunity

Using a syngeneic islet transplantation model system we have showed that in autoimmune type 1 diabetes transplanted islets are destroyed by the host immune system unless the transplanted islets lack class I major histocompatibility complex (MHC) molecules. Alternatively, immunomodulation of the host by induction of regulatory T cells prevented the destruction of autologous islet graft. We conclude that these approaches will allow successful transplantation of autologous islets derived from the host by stem cell or other technology without immunosuppression to reverse autoimmune type 1 diabetes

Emergence of human immunoprofiling in health and disease

The human immune system is critical for maintaining health and providing protection from infectious diseases and cancer. Major advances in our understanding of the immune system have largely emerged from studies using animal models such as mice. However, this mouse-centric research has also limited our ability to comprehend the human immune system and how it changes with age and disease state. The fact that we have yet to define what constitutes a normal human immune system has hampered our ability to diagnose, treat, and prevent many human diseases. Immunoprofiling that measures the frequency of human immune cells based upon their functional biomarkers is critical for immunotherapy. With major advances in flow cytometry, mass cytometry, and imaging technology it is now possible to rapidly characterize many types of immune cells for immunotherapy and for monitoring disease. In this article, we discuss recent progress in immunoprofiling of the human immune system and how this system changes with age, chronic diseases, and autoimmunity. We also discuss this in the historical context as it relates to the emergence of human immunology. New knowledge generated by immunoprofiling studies will allow better understanding and monitoring of immune cells and their application in clinical medicine

Reciprocity in microbiome and immune system interactions and its implications in disease and health.

Adaptation of the whole microbial normal flora residing in a host to its natural habitat over an evolutionary period has resulted in peaceful coexistence with mutual benefits for both microbiota and host in steady state. This symbiotic relationship between host and microbiota has a significant impact on shaping the immune response in the host to achieve an immune tolerance to microbiota but retaining the ability to respond to invading pathogens. Perturbation of this balance by manipulation of microbial communities in the host can lead to immune dysregulation and susceptibility to diseases. By studying the host in the absence of microbiota or with alteration of microbiota the complexity of microbial impact on the immune system can be resolved. Conversely, the study of microbiota in the absence of immune system factors can show how the immune system contributes to preservation of the host-microbiota balance. The absence of molecules involved in innate or adaptive immunity in knockout models can perturb the balance between host and microbiota further adding to more immune dysregulation. A better understanding of Microbiome-immune system interaction provides a new opportunity to identify biomarkers and drug targets. This will allow the development of new therapeutic agents for modulating the immune system to improve health with little or no toxicity. The study of interplay between host and microbiota has a promising role in the design of therapeutic interventions for immunopathological diseases arising from imbalanced host and microbiota interactions

Effect of Growth Stage on the Efficacy of Postemergence Herbicides on Four Weed Species of Direct-Seeded Rice

The efficacy of bispyribac-sodium, fenoxaprop + ethoxysulfuron, and penoxsulam + cyhalofop was evaluated against barnyardgrass, Chinese sprangletop, junglerice, and southern crabgrass when applied at four-, six-, and eight-leaf stages. When applied at the four-leaf stage, bispyribac-sodium provided greater than 97% control of barnyardgrass, junglerice, and southern crabgrass; however, it was slightly weak (74% control) on Chinese sprangletop. Irrespective of the weed species, fenoxaprop + ethoxysulfuron provided greater than 97% control when applied at the four-leaf stage. At the same leaf stage, penoxsulam + cyhalofop controlled 89 to 100% barnyardgrass, Chinese sprangletop, and junglerice and only 54% of southern crabgrass. The efficacy of herbicides was reduced when applied at the eight-leaf stage of the weeds; however, at this stage, fenoxaprop + ethoxysulfuron was effective in controlling 99% of Chinese sprangletop. The results demonstrate the importance of early herbicide application in controlling the weeds. The study identified that at the six-leaf stage of the weeds, fenoxaprop + ethoxysulfuron can effectively control Chinese sprangletop and southern crabgrass, penoxsulam + cyhalofop can effectively control Chinese sprangletop, and bispyribac-sodium can effectively control junglerice

Response of 10 elite “green super rice” genotypes to weed infestation in aerobic rice systems

In recent years, water and labor shortage in Southeast Asia is driving the farmers towards dry-seeded rice systems. Weed infestation is a serious threat for adoption of these systems. A study was conducted in the wet and dry seasons to evaluate the performance of 10 elite “Green Super Rice” (a recently named group of rice genotypes bred for unfavorable marginal environments) genotypes at two different weed infestation levels (partial and moderate weed control) under dryseeded conditions. Average yield loss due to weed competition in the partial weed control treatment ranged from 12-57% in the wet season and 2-23% in the dry season. In the partial weed control plots, the drought pyramiding genotype IR83140-B-11-B performed well, resulting in 2850 and 4610 kg ha-1 of yield in the wet and dry seasons, respectively. The yield loss of this genotype in the partial weed control plots relative to the moderate weed control plots was only 21% in the wet season and 10% in the dry season. Results clearly showed that grain yield in different genotypes were positively correlated with leaf area at an early stage of the crop. The study also found negative and linear correlation between grain yield and weed biomass at harvest, demonstrating the importance of weeds in dry-seeded rice systems. The study suggested that genotypes with a larger leaf area could be integrated with other weed management strategies to achieve sustainable weed control in dry-seeded rice systems

Effects of sorghum residue in presence of pre-emergence herbicides on emergence and biomass of Echinochloa colona and Chloris virgata

In conservation agriculture systems, farmers gain many advantages from retaining crop residue on the soil surface, but crop residue retention in these systems may intervene with the activity of pre-emergence herbicides. A pot study was conducted to evaluate the effect of different rates of pre-emergence herbicides [imazethapyr (100 and 150 g a. i. ha-1), isoxaflutole (100 and 200 g a. i. ha-1), metolachlor (1.5 and 2.25 kg a. i. ha-1), pendimethalin (2.25 and 3.38 kg a. i. ha-1) and prosulfocarb + metolachlor (2.5 and 3.75 kg a. i. ha-1)] on seedling emergence and biomass of Echinochloa colona and Chloris virgata when applied in the presence of sorghum residue at rates equivalent to (0, 3 and 6 t ha-1). When seeds of E. colona and C. virgata were not covered with sorghum residue, the seedling emergence and biomass of both weeds was inhibited by 93–100% and 56–100%, respectively, with the application (both rates) of isoxaflutole, metolachlor, pendimethalin and prosulfocarb + metolachlor. Using sorghum residue resulted in lower herbicide efficacy on both weeds. At 3 t ha-1 sorghum residue, E. colona emergence and biomass reduced by 38–100% and 30–100%, respectively, with application of isoxaflutole, metolachlor and pendimethalin (both rates) in comparison with the no-herbicide treatment. Similarly, the emergence and biomass of C. virgata was also reduced by 92–100% and 25–100%, respectively. The results of this study suggest that crop residue may influence efficacy of commonly used pre-emergence herbicides and that the amount of crop residue on the soil surface should be adjusted according to the nature of the pre-emergence herbicides to achieve adequate weed control