Balamurugan Shanmugaraj

Plant molecular farming has emerged as a promising platform to produce recombinant biopharmaceuticals. The expression of foreign proteins changes the host proteome and metabolome, and these changes might have an effect on the accumulation of recombinant proteins. In this study, we investigated how fusion partners and ER-retention strategies influence host responses during transient production of recombinant human interleukin-15 (IL-15) in Nicotiana benthamiana. Four IL-15 constructs carrying either an 8 × His tag or an IgG1 Fc fusion, with or without an N-terminal signal peptide and C-terminal SEKDEL motif (KD), were compared at 4 days post-infiltration. Western blot analysis detected IL-15 only in the Fc-fusion constructs. Plants expressing IL15-Fc accumulated more antioxidant enzymes and phenylpropanoid-derived phenolics. Expression of IL15-Fc with the SP/KD construct showed increased abundance of proteins involved in protein folding and translation, together with reduced representation of secondary metabolic pathways. Overall, the results demonstrate that fusion partner and SP/KD targeting strategy jointly shape the host response to recombinant IL-15 expression and should therefore be evaluated together during construct design for plant molecular farming.

Dengue is a vector-borne disease transmitted through mosquitoes that pose serious health issues globally. Dengue infection is caused by dengue virus (DENV) that circulates as four serotypes in endemic regions and accurate serotype differentiation is hindered by widespread serological cross-reactivity. DENV is composed of three structural and seven non-structural proteins and in the current study, all seven non-structural (NS) proteins were analyzed using an integrated in silico approach to identify candidate serotype-specific B-cell epitopes carrying potential diagnostic relevance. Multiple sequence alignment, pairwise identity assessment, and phylogenetic relationship of all four DENV serotype amino acid sequences were carried out. Linear B-cell epitopes were predicted using the BepiPred tool with parameters optimized to balance sensitivity and specificity and the ABCPred tool for further sequence-based epitope prediction. This was later followed by structure-based surface epitope prediction using ElliPro. The predicted epitopes were subsequently subjected to a two-step conservancy analysis to evaluate intra-serotype conservation and pan-serotype divergence. The multiple sequence alignment showed that high sequence conservation (~ 98-99%) was observed overall across NS proteins, yet specific aminoacid substitutions were identified that enabled serotype-level discrimination. Initial B-cell epitope prediction resulted in 355 epitopes and 1067 epitopes from BepiPred and ABCPred respectively. Antigenicity, allergenicity and toxicity filters were applied to retain potential antigenic epitopes. Further, initial stringent filtering criteria (≤ 75% intra-serotype conservation and ≤ 30% pan-serotype minimum identity) were applied to increase serotype-specific strictness of the candidate epitopes. Altogether all non-structural proteins yielded 121 epitopes from the BepiPred, ABCPred and ElliPro tools with stricter 50-75% intra-serotype conservation, and ≤ 25% pan-serotype minimum identity. Also, few of the predicted epitopes were in concordance with previous in silico or experimentally validated antigenic regions reported, supporting their biological relevance. Overlap with surface epitopes and stringent filtering suggest that the DENV NS proteins are made of distinct antigenic regions that makes them as potential candidates for serotype-specific differentiation. This workflow for epitope prediction and filtering provides a computational basis for utilizing epitopes for future experimental validation and diagnostic assay development.

Rare diseases, often called orphan diseases, affect a small number of individuals. They are associated with severe, chronic, debilitating and adverse health outcomes, sometimes leading to death. There are no effective treatments for most of the rare diseases, and hence the patients often rely on therapies that alleviate symptoms, which may require lifetime treatment. This will place a significant burden on patients and their families physically, emotionally and financially, affecting their overall well-being. In India, the healthcare resources are already over-stretched and hence addressing the needs of patients suffering from rare diseases is particularly complex due to the high costs of diagnosis and treatment, lack of awareness, and limited access to specialized services. However, several initiatives have been undertaken at the national level to address the challenges related to the diagnosis, treatment and surveillance of rare diseases. The National Policy for Rare Diseases first introduced in 2017, then revised and launched in 2021, provides a framework for India’s approach in managing rare diseases. Nevertheless, challenges such as inadequate implementation of policy, insufficient manufacturing of orphan drugs at the national level and the lack of an effective surveillance and data collection system hampered the progress in providing an effective public health response for rare diseases. This review provides an overview of the Indian rare disease policy emphasizing government initiatives to tackle the burden of rare diseases on patients, families and the healthcare system.

Background: House dust mites (HDM) are one of the significant indoor allergen sources which cause IgE-mediated responses in most of the allergic individuals. HDMs are found in human habitats worldwide and Der p 2 is one of the major clinically relevant HDM allergens involved in triggering allergic diseases. The recombinant production of Der p 2 in plant systems provides a cost-effective and viable platform for developing diagnostic kits and allergen-specific immunotherapy. Methods: The D. pteronyssinus Der p 2 allergen was transiently expressed in Nicotiana benthamiana and its immunogenicity was evaluated in mice. The Der p 2 coding sequence was cloned into a geminiviral plant expression vector and introduced into N. benthamiana leaves via Agrobacterium tumefaciens-mediated infiltration. Recombinant Der p 2 proteins were purified from the crude extracts and confirmed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and Western blot. The immunogenicity of the plant-produced Der p 2 proteins was further evaluated by immunizing mice following a prime–boost immunization regimen, and Der p 2-specific antibody responses were assessed by ELISA. Results: Recombinant Der p 2 was successfully expressed and purified from N. benthamiana, and immunized mice developed high levels of Der p 2-specific IgG antibodies, with antibody titers increased after booster immunization. Conclusions: The results demonstrate that the transient expression of Der p 2 in plants is a feasible and effective strategy for producing immunologically active recombinant allergen proteins for diagnostic and potential clinical applications.

Vaccination remains one of the effective strategies to control infectious diseases, thereby preventing millions of deaths each year globally. Veterinary vaccines protects animal and public health, enabling efficient production of livestock, reduce antibiotic use and also prevent zoonotic spill over events. Traditional vaccines were developed using live-attenuated or inactivated pathogens. However, the advancements in the genetic engineering and recombinant protein production technologies have made possible the vaccine design and production of recombinant vaccine antigens or immunotherapeutic molecules for both human and veterinary use. Most of the commercially available recombinant therapeutic proteins are produced in mammalian system which limits their feasibility, particularly for veterinary applications due to their high production costs. Therefore, the development of low cost products using alternative production platforms is highly essential. The utilization of plant expression system for the recombinant vaccine production has increased in the recent years due to its advantages such as low production costs, scalability, safety, and the ability to express complex proteins. This review provides a comprehensive overview of the vaccine antigens produced in plant system with a particular focus on vaccines targeting infectious diseases in ruminants and swine.

Arboviruses are responsible for many emerging and reemerging diseases that represent a significant public health threat globally, affecting millions of people annually and putting over half of the global population at risk. These viruses primarily depend on mosquito or tick vectors for transmission to vertebrate hosts. Ticks are one of the major vectors transmitting a wide range of arboviruses that are known to cause serious infectious diseases in both animals and humans. The geographic expansion and increasing prevalence of tick-borne viruses pose significant prevention and control challenges. Amid the global health challenges resulting from the Coronavirus disease pandemic and the recent resurgence of monkeypox, which has been designated a public health emergency of international concern, another febrile illness has been reported in northeastern China that has drawn attention. Recently, a new tick-borne virus, the Wetland virus associated with human febrile illness and closely related to the Crimean–Congo hemorrhagic fever virus, has been identified in a patient admitted to a hospital in Jinzhou, Liaoning Province, China, after a tick bite. The affected individuals showed variable degrees of clinical symptoms. It is essential to remain vigilant about this new viral outbreak. As it is a new virus, there are no reports available demonstrating effective vaccines or drugs for the treatment of the Wetland virus. In this review, an outline of the Wetland virus and insights into the tick-borne arboviral infections are provided. Further, the need for the development of effective treatments, surveillance measures, and prevention strategies to mitigate future outbreaks is also highlighted.

Oropouche virus is a neglected, emerging virus that belongs to the Peribunyaviridae family and has caused significant public health concerns, especially in South America. Since its discovery in the 1950s, this virus has demonstrated a considerable impact on public health through its silent spread and occasional outbreaks. At least 30 major outbreaks have been reported, with more than half a million cases documented in many countries including Brazil, Peru, Panama, Trinidad and Tobago. In 2024, more than 16,000 confirmed cases were reported, including four deaths. It is endemic to Amazon and is currently spreading beyond its territory to non-endemic countries. It has been linked to human death for the first time, raising major concerns about the threat this virus poses to public health. The virus is primarily transmitted through the bite of the midge Culicoides paraensis and possibly by certain mosquito species. Oropouche virus fever does not exhibit specific clinical symptoms and is therefore often undiagnosed or misdiagnosed as other arboviral diseases. Currently, there are no vaccines or antiviral treatment available; hence, disease prevention mainly focuses on vector control and personal protection measures. Understanding the comprehensive drivers influencing the emergence and spread of this disease is vital for developing effective control and prevention strategies. This infection has recently emerged as one of the most important viral diseases in Latin America and is likely to remain a considerable threat to global public health in the near future. Here, an overview of Oropouche virus, it’s clinical features, and pathogenesis are presented.