This review explores the mechanisms by which Human Immunodeficiency Virus type 1 (HIV-1) regulatory proteins manipulate host cellular pathways to promote viral replication and immune evasion. Key viral proteins, such as Nef, Vpu, Vif, Vpr, and Env, disrupt immune defenses by downregulating surface molecules such as CD4 (Cluster of Differentiation 4) and Major Histocompatibility Complex (MHC) class I, degrading antiviral enzymes like APOBEC3G (Apolipoprotein B mRNA editing catalytic polypeptide-3G) and SAMHD1 (Sterile Alpha Motif and Histidine Aspartate domain-containing protein 1), and counteracting restriction factors including BST-2 (Bone Marrow Stromal Antigen 2)/Tetherin and SERINC5 (Serin Incorporator 5). These interactions support viral persistence and contribute to the establishment of chronic infection. Emerging therapeutic strategies aim to disrupt these HIV-host interactions to restore innate antiviral responses and enhance immune clearance. Approaches such as stabilizing host restriction factors or blocking viral antagonists offer a promising alternative to conventional antiretroviral therapy. By targeting host-dependent pathways, these interventions may reduce drug resistance, tackle latent reservoirs, and provide a pathway toward sustained viral remission or functional cure.

(1) Background: The escalating crisis of multidrug-resistant (MDR) bacteria presents a formidable threat to global public health, necessitating the urgent development of alternative antimicrobial strategies. Nanoparticles (NPs) have emerged as a promising frontier in this effort, leveraging their unique physicochemical properties and multi-modal mechanisms of action to combat bacterial infections. This systematic review aims to comprehensively evaluate the current body of evidence on the dynamic interplay between nanoparticles and bacterial resistance. (2) Methods: A comprehensive search of electronic databases, including PubMed, Scopus, and Web of Science, was performed using a combination of keywords and Medical Subject Headings (MeSH) terms to identify relevant primary research articles. Eligibility criteria focused on studies evaluating the antimicrobial effects of nanoparticles on MDR bacterial strains, reporting on mechanisms of action, efficacy, or resistance development. (3) Results: The synthesis of findings revealed that nanoparticles exert their antimicrobial effects through multiple pathways, including the generation of reactive oxygen species (ROS), direct disruption of bacterial membranes, and the release of toxic ions. However, the analysis also confirmed that bacteria have evolved sophisticated defense mechanisms against nanoparticles, including surface modifications that prevent adhesion, upregulation of efflux pumps, and chemical neutralization of toxic ions. (4) Conclusions: Nanoparticles represent a potent and versatile tool in the global effort to combat antimicrobial resistance. Their long-term efficacy is not guaranteed, as bacteria have shown a remarkable capacity for adaptation. The future of this field lies in the development of rationally designed nanoparticle systems that not only possess intrinsic antimicrobial activity but also actively disarm bacterial resistance mechanisms. This includes the strategic use of synergistic combinations with conventional antibiotics and the exploration of resistance-agnostic approaches like nanotoxoid vaccines.

Neurotropic viruses have evolved sophisticated mechanisms to evade host immune responses within the central nervous system (CNS), enabling viral replication, persistence, latency, and neuropathogenesis while minimizing irreversible neuronal damage. Unlike peripheral tissues, the CNS requires tightly regulated antiviral immunity to balance effective pathogen control with the preservation of neural function. This review examines the diverse yet convergent immune evasion strategies employed by major neurotropic RNA and DNA viruses, including herpes simplex virus (HSV), varicella-zoster virus (VZV), cytomegalovirus (CMV), rabies virus (RABV), flaviviruses, alphaviruses, enteroviruses, and JC virus (JCV). We discuss viral interference with innate immune sensing pathways, including RIG-I-like receptors (RLRs) and cyclic GMP–AMP synthase–stimulator of interferon genes (cGAS–STING) signaling, inhibition of type I interferon induction and Janus kinase–signal transducer and activator of transcription (JAK–STAT) signaling, modulation of interferon-stimulated effector mechanisms, and disruption of antigen presentation and adaptive immune surveillance. The review further highlights the distinct roles of viral latency, long-term persistence, neuronal–glial interactions, and metabolic reprogramming in facilitating prolonged infection within the CNS. Emerging evidence indicates that successful neurotropic viruses rarely achieve immune evasion through complete suppression of host defenses; instead, they fine-tune antiviral responses to preserve host cell viability while preventing viral clearance. Finally, we discuss current knowledge gaps and emphasize the need for advanced human-relevant models, single-cell and spatial multi-omics, and systems-level approaches to better define virus–host interactions within the CNS. A deeper understanding of these integrated immune evasion networks may reveal novel therapeutic strategies that enhance antiviral immunity while limiting neuroinflammation and preserving neurological function.