Search Results (68)

The broad-spectrum insect growth regulator (IGR) and insecticide 2-((1-(4-Phenoxyphenoxy)propan-2-yl)oxy)pyridine (MPEP; also known as pyriproxyfen) is increasingly being used to address public health programs for vector control, initiated by the spread of Zika virus in 2015–2016. While considered relatively safe for humans under normal conditions, limited toxicology data are available. Current studies were undertaken to address the data gap regarding potential immunotoxicity of MPEP, with particular emphasis on host resistance to viral infection. Hsd:Harlan Sprague Dawley SD^® rats were treated for 28 days by oral gavage with doses of 0, 62.5, 125, 250 or 500 mg/kg/day of MPEP in corn oil. There was a dose-dependent increase in liver weights which is consistent with the liver playing a dominant role in MPEP metabolism. However, no histological correlates were observed. Following treatment, rats were subjected to a battery of immune tests as well as an established rat model of influenza virus infection to provide a comprehensive assessment of immune function and host resistance. While several of the immune tests showed minor exposure-related changes, evidenced by negative dose–response trends, most did not show significant differences in any of the MPEP treatment groups relative to vehicle control. Most notable was a negative trend in pulmonary mononuclear cell phagocytosis with increases in dose of MPEP. There was also a positive trend in early humoral immune response (5 days after immunization) to keyhole limpet hemocyanin (KLH) as evidenced by increased serum anti-KLH IgM antibodies which was followed later (14 days following immunization) by decreasing trends in anti-KLH IgM and IgG antibody levels. However, MPEP treatment had no effect on the ability of rats to clear the influenza virus nor the T-dependent IgM and IgG antibody response to the virus. The lack of effects of MPEP on host resistance to influenza suggests the immune effects were minimal and unlikely to present a hazard with respect to susceptibility to respiratory viral infection. Full article

Penaeus vannamei hemocyanin (PvHMC) exhibits multifunctional roles in immunity, often mediated by various post-translational modifications. While linear ubiquitination catalyzed by LUBAC in mammals regulates immune signaling, its role in crustacean immunity remains unclear. Here, we investigated the regulatory mechanism of PvHMC linear ubiquitination mediated by an E3 ligase PvLUBEL (a HOIP homolog), with emphasis on its role in shrimp immunity defending against diverse pathogens. We detected linear ubiquitination of PvHMC in multiple tissues, including hemocytes and the hepatopancreas. During Vibrio parahaemolyticus infection, the expression of PvLUBEL and the level of PvHMC linear ubiquitination were suppressed, whereas infection by white spot syndrome virus (WSSV) led to their upregulation. Structural analyses revealed that PvLUBEL, which shares a conserved RING-IBR-RING (RBR) domain with mammalian HOIP, serves as the catalytic subunit. Notably, inhibition of PvLUBEL via HOIPIN-1 (a covalent inhibitor) or RNA interference (RNAi) significantly reduced PvHMC linear ubiquitination, thereby increasing pathogen proliferation and decreasing host survival. These findings unveil a novel post-translational regulatory mechanism in which PvLUBEL-mediated linear ubiquitination of PvHMC underpins the shrimp immune response against aquaculture pathogens. Full article

Trace mineral supplementation is critical for shrimp aquaculture sustainability, yet the bioavailability of conventional inorganic forms remains suboptimal. The study investigated the effects of inorganic (IM) and organic (OM) trace mineral premixes at varying doses on growth, physiological responses, and gut microbiota in white shrimp (Penaeus vannamei). Five experimental diets were formulated: a basal control (no supplementation), full-dose IM (IM100), half-dose IM (IM50), half-dose OM (OM50), and one-third dose OM (OM33). A total of 800 shrimp were randomly distributed into 20 tanks for an 8-week feeding experiment. The results showed that shrimp fed diets OM50 and IM100 had significantly higher total protein content in the plasma, lower levels of total cholesterol and triglyceride, and enhanced antioxidant capacity and immune response (greater activities of T-SOD, GPX, and PO, lower content of MDA, higher content of hemocyanin, and upregulated expression of cat, gpx, and Hemo). Furthermore, OM50 group showed superior mineral bioaccumulation, particularly for Zn in the hepatopancreas and whole body, and Cu in the whole body, accompanied by upregulated expression of mineral transporter-related (ZIP14, ZnT6, and MT). Moreover, diet OM50 resulted in a higher abundance of potential probiotic bacteria (including Pseudomonas and Enterococcus) and a lower abundance of potential pathogenic bacteria (including Vibrio and Planctomicrobium). The findings indicated that organic trace minerals premix at half the conventional dosage can effectively enhance its bioavailability, significantly improve the health status, and beneficially modify intestinal microbiota communities of shrimp, suggesting superior efficiency compared to inorganic forms. Full article

Hemocyanins are oxygen-transporting proteins found in crustaceans and other arthropods, playing key roles in immune defense and metabolic regulation. Due to their stability and bioactive properties, Hcs have gained increasing interest in biotechnological and biomedical applications. However, detailed biophysical characterization is crucial to understanding their functional potential. In this study, the hemocyanin was extracted and purified from Macrobrachium acanthurus (HcMac) using ultracentrifugation and size-exclusion chromatography. The molecular mass of HcMac was determined by SDS-PAGE electrophoresis, MALDI-TOF mass spectrometry, and analytical ultracentrifugation. Spectroscopic analyses, including UV-Vis absorption, fluorescence emission, and light scattering intensity, were used to assess the structural stability of the compound under various pH conditions. HcMac was identified as a hexameric protein (~450 kDa) composed of monomeric subunits of 75 and 76 kDa. The protein maintained its oligomeric stability and oxygen-binding affinity in the pH range of 5.0–7.4. However, extreme pH conditions (below 4.4 and above 7.5) induced structural alterations, leading to dissociation and conformational changes, as evidenced by fluorescence emission and UV-Vis spectra. The isoelectric point was determined to be between pH 4.3 and 5.3, consistent with other crustacean HCs. These findings reinforce the structural robustness of HcMac and suggest its potential for biotechnological applications. The high stability of HcMac under physiological pH conditions indicates its suitability for biomedical research, including immunomodulatory and antimicrobial applications. Future studies integrating bioinformatics, proteomics, and immunological assays will be essential to explore the therapeutic potential of HcMac. Full article

This review compiles information on the biochemistry of spider reproduction, from vitellogenesis to postembryonic development. Despite the diversity of spiders, biochemical studies on their reproduction remain scarce. The structures, functions, and relationships of vitellogenins and lipovitellins across different groups are compared. Information on two vitellogenin-associated proteins (30 and 47 kDa) is presented and discussed. By analyzing females at different reproductive stages—previtellogenesis, early vitellogenesis, vitellogenesis, and postvitellogenesis—as well as males, we examined lipid and fatty acid synthesis, mobilization, and accumulation in the yolk. Lipid dynamics across vitellogenic organs, such as the intestinal diverticula, hemolymph, and ovaries, were established. Structural lipids, mainly phosphatidylcholine and phosphatidylethanolamine, were the predominant yolk components, followed by triacylglycerols. The gonadosomatic and hepatosomatic indices are described for the first time in spiders, providing a new tool for studying vitellogenesis. Hemocyanin was detected in early spider eggs, suggesting a role in organogenesis, with its concentration increasing in later embryonic stages. In contrast, lipovitellin consumption was observed throughout embryonic development until juvenile emergence. The data compiled in this review provide valuable insights into the molecular interactions underlying a key process for oviparous animals. Full article

Background: Personalized cancer vaccines based on tumor neoantigens show great potential in cancer immunotherapy due to their high safety and specificity. However, it is inherently difficult to realize the efficiently targeted delivery of personalized cancer vaccines to antigen-presenting cells (APCs). Methods: This study aimed to address these challenges by developing and evaluating a personalized cancer vaccine based on antibody–antigen complexes, which was designed to enhance antitumor effects by increasing the utilization of tumor neoantigens by APCs. Mice were immunized with a carrier protein, keyhole limpet hemocyanin (KLH), to induce the production of antibodies against KLH. Subsequently, mice were immunized with KLH loaded with tumor neoantigens and the immunoadjuvant CpG ODN and underwent immunological analysis to evaluate the immune and antitumor effects. Results: The results showed that preimmunization with KLH could promote the uptake of the personalized KLH-based tumor vaccine, which was enhanced by dendritic cells (DCs) and macrophages (Mφs), by strengthening the T-cell immune responses to tumors. Conclusions: Collectively, this work provides a new idea for the targeted delivery of personalized cancer vaccines. Full article

Shrimp are highly favored by consumers for their delicious taste and rich nutritional value. However, reports of allergic reactions caused by shrimp and its derivatives have been increasing, significantly impacting consumer health and posing a growing global food safety concern. This article introduces the structure and biochemical characteristics of major allergenic proteins in shrimp, including tropomyosin (TM), arginine kinase, sarcoplasmic calcium-binding protein, myosin light chain, troponin C, and hemocyanin. Currently, there is no effective treatment for shrimp allergies, and prevention is mainly achieved by avoiding consumption. The study of shrimp allergen sensitization reduction technology is of great significance to the development of hypoallergenic or desensitized products. The article provides a detailed overview of the effects of common processing techniques, including physical, chemical, biological, and combined methods, on the allergenicity of shrimp allergens; for instance, the binding rate to immunoglobulin E (IgE) was reduced by 73.59% after treating TM with high pressure (500 MPa) at 55 °C for 10 min and the recognition rate of TM to IgE decreased by 89.4% on average after treating TM with pepsin (30 μg/mL, pH 2) for 2 h. These techniques provide references for the development of hypoallergenic aquatic products or desensitized foods. Full article

The world obeys quantum physics and quantum computing presents an alternative way to map physical problems to systems that follow the same laws. Such computation fundamentally constitutes a better way to understand the most challenging quantum problems. One such problem is the accurate simulation of highly correlated quantum systems. Still, modern-day quantum hardware has limitations and only allows for the modeling of simple systems. Here, we present for the first time a quantum computer model simulation of a complex hemocyanin molecule, which is an important respiratory protein involved in various physiological processes and is also used as a key component in therapeutic vaccines for cancer. To characterize the mechanism by which hemocyanin transports oxygen, variational quantum eigensolver (VQE) and quantum embedding methods are used in the context of dynamic mean field theory to solve the Anderson impurity model (AIM). Finally, it is concluded that the magnetic structure of hemocyanin is largely influenced by the many-body correction and that the computational effort for solving correlated electron systems could be substantially reduced with the introduction of quantum computing algorithms. We encourage the use of the Hamiltonian systems presented in this paper as a benchmark for testing quantum computing algorithms’ efficiency for chemistry applications. Full article

Background: Lumpy skin disease virus (Poxviridae family—Capripoxvirus genus) is the aetiological agent of LSD, a disease primarily transmitted by hematophagous biting, affecting principally cattle. Currently, only live attenuated vaccines are commercially available, but their use is limited to endemic areas. There is a need for safer vaccines, especially in LSD-free countries. This research aims to develop and test a safe and efficacious inactivated vaccine. Moreover, in this study, we used keyhole limpet hemocyanin (KLH) as a positive marker to distinguish infected from vaccinated animals (DIVA). Methods: Lumpy skin disease virus was propagated on primary lamb testis cells and Madin–Darby bovine kidney cells (PLT and MDBK, respectively), and four inactivated vaccines were produced. The vaccines differed from each other with the addition or not of KLH and in cells used for virus propagation. To evaluate the safety and immunogenicity, the vaccines and two placebos were administered to six groups comprising six male calves each, and antibody response was investigated using both an enzyme-linked immunosorbent assay (ELISA) and a serum neutralization (SN) test. In addition, the LSD/γ-interferon test and KLH (IgM-IgG) ELISA were performed on the collected samples. Furthermore, the use of KLH allowed us to distinguish vaccinated animals in the ELISA results, without any interference on the strength of the immune response against the LSDV. Finally, the efficacy of one of four vaccines was investigated through a challenge, in which one group of vaccinated animals and one animal control group were infected with a live field strain of LSDV. Results: Four out of the six control animals showed severe clinical signs suggestive of LSD, and, therefore, were euthanized for overcoming the predetermined limit of clinical score. By contrast, the vaccinated animals showed only mild symptoms, suggesting a reduction in severe disease notwithstanding the incapability of the vaccine in reducing the virus shedding. Conclusion: The vaccines produced were safe and able to elicit both a humoral and a cellular immune response, characteristics that, together with the demonstrated efficacy, make our vaccine a good candidate for countering the LSD spread in disease-free countries, thus also facilitating disease containment throughout the application of a DIVA strategy. Full article

TNF receptor-associated factors (TRAFs) function as intracellular adaptor proteins utilized by members of the TNF receptor superfamily, such as CD40. Among the TRAF family proteins, TRAF5 has been identified as a potential regulator of CD40. However, it remains unclear whether TRAF5 regulates the generation of germinal center (GC) B cells and antigen-specific antibody production in the T-dependent (TD) immune response. TRAF5-deficient (Traf5^−/−) and TRAF5-sufficient (Traf5^+/+) mice were immunized in the footpad with 2,4,6-trinitrophenol-conjugated keyhole limpet hemocyanin (TNP-KLH) and complete Freund’s adjuvant (CFA). We found that GC B cell generation and antigen-specific IgM and IgG1 production were significantly impaired in Traf5^−/− mice compared to Traf5^+/+ mice. The expression levels of CD40-target genes Fas and Lta, which are involved in GC formation, were significantly decreased in B220⁺ cells isolated from immunized Traf5^−/− mice. Traf5^−/− B cells showed decreased antibody production, proliferation, and induction of CD40-target genes Tnfaip3, Tnfsf4, and Cd80 in response to agonistic Fc-CD40L protein in vitro. Furthermore, administration of TNP-KLH and Fc-CD40L to Traf5^−/− mice resulted in a severe loss of GC B cell development. These results highlight the crucial role of TRAF5 in driving CD40-mediated TD immune response in vivo. Full article

Background: The giant keyhole limpet Megathura crenulata is a gastropod mollusk (Fissurella superfamily) that is endemic to the eastern Pacific coast from southern California, USA, to Baja California Sur, Mexico. M. crenulata is socioeconomically important as it produces a potent immune-stimulating protein, called Keyhole Limpet Hemocyanin, which is extracted in vivo and utilized for vaccine development. However, ecological studies are scarce and genetic knowledge of the species needs to be improved. Our objectives were to assemble and annotate the mitogenome of M. crenulata, and to assess its phylogenetic relationships with other marine gastropods and to evaluate its population genetic diversity and structure. Methods: Samples were collected for mitogenome assembly (n = 3) spanning its geographic range, Puerto Canoas (PCA) and Punta Eugenia (PEU), Mexico, and California (CAL), USA. Total DNA was extracted from gills sequenced using Illumina paired-end 150-bp-read sequencing. Reads were cleaned, trimmed, assembled de novo, and annotated. In addition, 125 samples from eight locations were analyzed for genetic diversity and structure analysis at the 16s rRNA and COX1 genes. Results: The M. crenulata mitogenomes had lengths of 16,788 bp (PCA) and 16,787 bp (PEU) and were composed of 13 protein-coding regions, 22 tRNAs, two rRNAs, and the D-Loop region. In terms of phylogeographic diversity and structure, we found a panmictic population that has experienced recent demographic expansion with low nucleotide diversity (0.002), high haplotypic diversity (0.915), and low φ_ST (0.047). Conclusions: Genetic insights into the giant keyhole limpet provides tools for its management and conservation by delimiting fishing regions with low genetic diversity and/or genetically discrete units. Full article

Melanoma is one of the most common tumors worldwide, and new approaches and antitumor drugs for therapy are being investigated. Among the promising biomolecules of natural origin for antitumor research are gastropodan hemocyanins—highly immunogenic multimeric glycoproteins used as antitumor agents and components of therapeutic vaccines in human and mouse cancer models. A murine melanoma model established in C57BL/6 mice of the B16F10 cell line was used to study anticancer modified oxidized hemocyanins (Ox-Hcs) that were administered to experimental animals (100 μg/mouse) under different regimens: mild, intensive, and with sensitization. The solid tumor growth, antitumor response, cell infiltration in tumors, and survival were assessed using flow cytometry, ELISA, and cytotoxicity assays. Therapy with Ox-RtH or Ox-HaH resulted in the generation of enhanced specific immune response (increased levels of tumor-infiltrated mature NK cells (CD27+CD11b+) in sensitized groups and of macrophages in the intensively immunized animals) and tumor suppression. Beneficial effects such as delayed tumor incidence and growth as well as prolonged survival of tumor-bearing animals have been observed. High levels of melanoma-specific CTLs that mediate cytotoxic effects on tumor cells; tumor-infiltrating IgM antibodies expected to enhance antibody-dependent cellular cytotoxicity; type M1 macrophages, which stimulate the Th1 response and cytotoxic cells; and proinflammatory cytokines, were also observed after Ox-Hcs administration. The modified Hcs showed strong antitumor properties in different administration regimens in a murine model of melanoma with potential for future application in humans. Full article

The literature shows that maternal stress can influence behavior and immune function in F1. Yet, most studies on these are from the laboratory, and replicated studies on the mechanisms by which maternal stress drives individual characteristics are still not fully understood in wild animals. We manipulated high- and low-density parental population density using large-scale field enclosures and examined behavior and immune traits. Within the field enclosures, we assessed anti-keyhole limpet hemocyanin immunoglobulin G (anti-KLH IgG) level, phytohemagglutinin (PHA) responses, hematology, cytokines, the depressive and anxiety-like behaviors and prevalence and intensity of coccidial infection. We then collected brain tissue from juvenile voles born at high or low density, quantified mRNA and protein expression of corticotropin-releasing hormone (CRH) and glucocorticoid receptor gene (NR3C1) and measured DNA methylation at CpG sites in a region that was highly conserved with the prairie vole CRH and NR3C1 promoter. At high density, we found that the F1 had a lower DNA methylation level of CRH and a higher DNA methylation level of NR3C1, which resulted in an increase in the expression levels of the CRH mRNA and protein expression and further reduced the expression levels of the NR3C1 mRNA and protein expression, and ultimately led to have delayed responses to acute immobilization stress. Juvenile voles born at high density also reduced anti-KLH IgG levels and PHA responses, increased cytokines, and depressive and anxiety-like behaviors, and the effects further led to higher coccidial infection. From the perspective of population density inducing the changes in behavior and immunity at the brain level, our results showed a physiological epigenetic mechanism for population self-regulation in voles. Our results indicate that altering the prenatal intrinsic stress environment can fundamentally impact behavior and immunity by DNA methylation of HPA-axis genes and can further drive population fluctuations in wild animals. Full article

Ananteris is a scorpion genus that inhabits dry and seasonal areas of South and Central America. It is located in a distinctive morpho-group of Buthids, the ‘Ananteris group’, which also includes species distributed in the Old World. Because of the lack of information on venom composition, the study of Ananteris species could have biological and medical relevance. We conducted a venomics analysis of Ananteris platnicki, a tiny scorpion that inhabits Panama and Costa Rica, which shows the presence of putative toxins targeting ion channels, as well as proteins with similarity to hyaluronidases, proteinases, phospholipases A₂, members of the CAP-domain family, and hemocyanins, among others. Venom proteolytic and hyaluronidase activities were corroborated. The determination of the primary sequences carried out by mass spectrometry evidences that several peptides are similar to the toxins present in venoms from Old World scorpion genera such as Mesobuthus, Lychas, and Isometrus, but others present in Tityus and Centruroides toxins. Even when this venom displays the characteristic protein families found in all Buthids, with a predominance of putative Na⁺-channel toxins and proteinases, some identified partial sequences are not common in venoms of the New World species, suggesting its differentiation into a distinctive group separated from other Buthids. Full article

The discovery and investigation of new natural compounds with antimicrobial activity are new potential strategies to reduce the spread of antimicrobial resistance. The presented study reveals, for the first time, the promising antibacterial potential of two fractions from Cornu aspersum mucus with an MW < 20 kDa and an MW > 20 kDa against five bacterial pathogens—Bacillus cereus 1085, Propionibacterium acnes 1897, Salmonella enterica 8691, Enterococcus faecalis 3915, and Enterococcus faecium 8754. Using de novo sequencing, 16 novel peptides with potential antibacterial activity were identified in a fraction with an MW < 20 kDa. Some bioactive compounds in a mucus fraction with an MW > 20 kDa were determined via a proteomic analysis on 12% sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) and bioinformatics. High homology with proteins and glycoproteins was found, with potential antibacterial activity in mucus proteins named aspernin, hemocyanins, H-lectins, and L-amino acid oxidase-like protein, as well as mucins (mucin-5AC, mucin-5B, mucin-2, and mucin-17). We hypothesize that the synergy between the bioactive components determined in the composition of the fraction > 20 kDa are responsible for the high antibacterial activity against the tested pathogens in concentrations between 32 and 128 µg/mL, which is comparable to vancomycin, but without cytotoxic effects on model eukaryotic cells of Saccharomyces cerevisiae. Additionally, a positive effect, by reducing the levels of intracellular oxidative damage and increasing antioxidant capacity, on S. cerevisiae cells was found for both mucus extract fractions of C. aspersum. These findings may serve as a basis for further studies to develop a new antibacterial agent preventing the development of antibiotic resistance. Full article