The broad relationship between the immune system and cancer is opening a new hallmark to explore for nanomedicine. Here, all the common and synergy points between both areas are reviewed and described, and the recent approaches which show the progress from the bench to the beside to biomarkers developed in nanomedicine and onco-immunotherapy.

Fish, like all other animals, are exposed to constant contact with microbes, both on their skin and on the surfaces of their respiratory and digestive systems. Fish have a system of non-specific immune responses that provides them with initial protection against infection and allows them to survive under normal conditions despite the presence of these potential invaders. However, fish are less protected against invading diseases than other marine vertebrates because their epidermal surface, composed primarily of living cells, lacks the keratinized skin that serves as an efficient natural barrier in other marine vertebrates. Antimicrobial peptides (AMPs) are one type of innate immune protection present in all life forms. AMPs have been shown to have a broader range of biological effects than conventional antibiotics, including antibacterial, antiviral, antiprotozoal, and antifungal effects. Although other AMPs, such as defensins and hepcidins, are found in all vertebrates and are relatively well conserved, piscidins are found exclusively in Teleost fish and are not found in any other animal. Therefore, there is less information on the expression and bioactivity of piscidins than on other AMPs. Piscidins are highly effective against Gram-positive and Gram-negative bacteria that cause disease in fish and humans and have the potential to be used as pharmacological anti-infectives in biomedicine and aquaculture. To better understand the potential benefits and limitations of using these peptides as therapeutic agents, we are conducting a comprehensive study of the Teleost piscidins included in the “reviewed” category of the UniProt database using bioinformatics tools. They all have amphipathic alpha-helical structures. The amphipathic architecture of piscidin peptides and positively charged residues influence their antibacterial activity. These alpha-helices are intriguing antimicrobial drugs due to their stability in high-salt and metal environments. New treatments for multidrug-resistant bacteria, cancer, and inflammation may be inspired by piscidin peptides.

Interest in natural biopreservatives has increased significantly due to growing consumer demand for safer and more environmentally friendly food preservation strategies. Antimicrobial peptides (AMPs), naturally occurring molecules (typically <10 kDa), have emerged as a promising alternative to synthetic chemical preservatives. Found in bacteria, fungi, plants, and animals, including humans, AMPs play a crucial role in innate immune defense. Their antibacterial and antioxidant effects enable them to prevent microbial spoilage and extend the shelf life of food, reducing the need for artificial additives. AMPs are biodegradable and environmentally friendly, and they specifically target harmful microorganisms, minimizing disruption to beneficial microorganisms. Despite their promising properties, challenges such as stability, cost and potential sensory impairment limit their wide application. Recent advances, such as encapsulation techniques and nanotechnology, have shown remarkable potential to improve the stability and functionality of AMPs in complex food systems. In addition, AMPs derived from edible mushrooms represent a sustainable and natural approach to food preservation and could offer effective solutions against foodborne pathogens and oxidative spoilage. This review examines the structural features, mechanisms of action and practical applications of AMPs in food protection, with a particular focus on their innovative integration with nanotechnology to address current food safety challenges.

Microbial resistance is a global health problem that will increase over time. Advances in insect antimicrobial peptides (AMPs) offer a powerful new approach to combat antimicrobial resistance. Invertebrates represent a rich group of animals for the discovery of new antimicrobial agents due to their high diversity and the presence of adaptive immunity or “immune priming”. Here, we report a priming approach for Tenebrio molitor that simulates natural infection via the oral route. This oral administration has the advantage of minimizing the stress caused by conventional priming techniques and could be a viable method for mealworm immunity studies. When using inactivated microorganisms for oral priming, our results showed an increased survival of T. molitor larvae after exposure to various pathogens. This finding was consistent with the induction of antimicrobial activity in the hemolymph of primed larvae. Interestingly, the hemolymph of larvae orally primed with Escherichia coli showed constitutive activity against Staphylococcus aureus and heterologous activity for other Gram-negative bacteria, such as Salmonella enterica. The priming of T. molitor is generally performed via injection of the microorganism. To our knowledge, this is the first report describing the oral administration of heat-inactivated microorganisms for priming mealworms. This technique has the advantage of reducing the stress that occurs with the conventional methods for priming vertebrates.

The immune systems of all vertebrates contain cathelicidins, a family of antimicrobial peptides. Cathelicidins are a type of innate immune effector that have a number of biological functions, including a well-known direct antibacterial action and immunomodulatory function. In search of new templates for antimicrobial peptide discovery, we have identified and characterized the cathelicidin of the small mammal Talpa occidentalis. We describe the heterogeneity of cathelicidin in the order Eulipotyphla in relation to the Iberian mole and predict its antibacterial activity using bioinformatics tools. In an effort to correlate these findings, we derived the putative active peptide and performed in vitro hemolysis and antimicrobial activity assays, confirming that Iberian mole cathelicidins are antimicrobial. Our results showed that the Iberian mole putative peptide, named To-KL37 (KLFGKVGNLLQKGWQKIKNIGRRIKDFFRNIRPMQEA) has antibacterial and antifungal activity. Understanding the antimicrobial defense of insectivores may help scientists prevent the spread of pathogens to humans. We hope that this study can also provide new, effective antibacterial peptides for future drug development.

Acanthamoeba infections are hindered by limitations including prolonged treatment duration, cytotoxicity, limited efficacy against the resistant cystic stage, and a high rate of recurrence. Antimicrobial peptides (AMPs) demonstrate broad-spectrum antimicrobial activity, rapid mechanism of action, low potential for inducing resistance, and efficacy against both trophozoite and cyst forms, highlighting their potential as promising alternatives in the treatment of these infections. Herein, we report the amoebicidal activity of various peptides derived from cathelicidins and piscidins against Acanthamoeba castellanii Neff. Afterwards, the impact of the most effective peptide on the clinical features of a clinical strain of Acanthamoeba castellanii was evaluated using a fluorescence imaging system. Peptide OH_KR34 was the most active against A. castellanii Neff with an IC₅₀ values of 2.00 ± 0.58 µM. OH_KR34 was able to inhibit the clinical strain of A. castellanii (L10) with an IC₅₀ of 5.75 ± 0.30 μM. We demonstrated that the peptide OH_KR34 (related to OH-CATH) induces cytoskeletal damage and trigger apoptosis-like process by disrupting cell membrane permeability, mitochondrial dysfunction and DNA fragmentation. This antimicrobial peptide could therefore offer a potential target to develop new anti-parasitic drugs.