The Prospect of Nanoparticle Systems for Modulating Immune Cell Polarization During Central Nervous System Infection

Navigating the nano-bio immune interface: advancements and challenges in CNS nanotherapeutics

In recent years, significant advancements have been made in utilizing nanoparticles (NPs) to modulate immune responses within the central nervous system (CNS), offering new opportunities for nanotherapeutic interventions in neurological disorders. NPs can serve as carriers for immunomodulatory agents or platforms for delivering nucleic acid-based therapeutics to regulate gene expression and modulate immune responses. Several studies have demonstrated the efficacy of NP-mediated immune modulation in preclinical models of neurological diseases, including multiple sclerosis, stroke, Alzheimer's disease, and Parkinson's disease. While challenges remain, advancements in NPs engineering and design have led to the development of NPs using diverse strategies to overcome these challenges. The nano-bio interface with the immune system is key in the conceptualization of NPs to efficiently act as nanotherapeutics in the CNS. The biomolecular corona plays a pivotal role in dictating NPs behavior and immune recognition within the CNS, giving researchers the opportunity to optimize NPs design and surface modifications to minimize immunogenicity and enhance biocompatibility. Here, we review how NPs interact with the CNS immune system, focusing on immunosurveillance of NPs, NP-induced immune reprogramming and the impact of the biomolecular corona on NPs behavior in CNS immune responses. The integration of NPs into CNS nanotherapeutics offers promising opportunities for addressing the complex challenges of acute and chronic neurological conditions and pathologies, also in the context of preventive and rehabilitative medicine. By harnessing the nano-bio immune interface and understanding the significance of the biomolecular corona, researchers can develop targeted, safe, and effective nanotherapeutic interventions for a wide range of CNS disorders to improve treatment and rehabilitation. These advancements have the potential to revolutionize the treatment landscape of neurological diseases, offering promising solutions for improved patient care and quality of life in the future.

Bacterial meningitis in Africa

Bacterial meningitis differs globally, and the incidence and case fatality rates vary by region, country, pathogen, and age group; being a life-threatening disease with a high case fatality rate and long-term complications in low-income countries. Africa has the most significant prevalence of bacterial meningitis illness, and the outbreaks typically vary with the season and the geographic location, with a high incidence in the meningitis belt of the sub-Saharan area from Senegal to Ethiopia. Streptococcus pneumoniae (pneumococcus) and Neisseria meningitidis (meningococcus) are the main etiological agents of bacterial meningitis in adults and children above the age of one. Streptococcus agalactiae (group B Streptococcus), Escherichia coli, and Staphylococcus aureus are neonatal meningitis's most common causal agents. Despite efforts to vaccinate against the most common causes of bacterial neuro-infections, bacterial meningitis remains a significant cause of mortality and morbidity in Africa, with children below 5 years bearing the heaviest disease burden. The factors attributed to this continued high disease burden include poor infrastructure, continued war, instability, and difficulty in diagnosis of bacterial neuro-infections leading to delay in treatment and hence high morbidity. Despite having the highest disease burden, there is a paucity of African data on bacterial meningitis. In this article, we discuss the common etiologies of bacterial neuroinfectious diseases, diagnosis and the interplay between microorganisms and the immune system, and the value of neuroimmune changes in diagnostics and therapeutics.

Immunomodulatory and Antiprotozoal Potential of Fabricated Sesamum radiatum Oil/Polyvinylpyrrolidone/Au Polymeric Bionanocomposite Film

A unique morphological Sesamum radiatum oil/polyvinylpyrrolidone/gold polymeric bionanocomposite film was synthesized using the S. radiatum oil dispersed in a polymeric polyvinylpyrrolidone (PVP) matrix and decorated with gold nanoparticles (AuNPs). The chemical and physical characteristics as well as the thermal stability of the synthesized bionanocomposite film were investigated using various spectroscopic and microscopic techniques. The microscopic analysis confirmed well dispersed AuNPs in the PVP- S. radiatum oil matrix with particle size of 100 nm. Immunomodulatory and antiprotozoal potentials of the suggested bionanocomposite film were evaluated for lipopolysaccharide-induced BV-2 microglia and against L. amazonensis, L. mexicana promastigotes and T. cruzi epimastigotes, respectively. The results exerted outstanding reduction of inflammatory cytokines' (IL-6 and TNFα) secretions after pretreatment of bionanocomposite. The bionanocomposite exhibited large inhibitory effects on certain cell signaling components that are related to the activation of expression of proinflammatory cytokines. Additionally, AuNPs and bionanocomposite exhibited excellent growth inhibition of L. mexicana and L. amazonensis promastigotes with IC50 (1.71 ± 1.49, 1.68 ± 0.75) and (1.12 ± 1.10, 1.42 ± 0.69), respectively. However, the nanomaterials showed moderate activity towards T. cruzi. All outcomes indicated promising immunomodulatory, antiprotozoal, and photocatalytic potentials for the synthesized S. radiatum oil/PVP/Au polymeric bionanocomposite.