Horacio Zamudio-Meza

Background: Biomedical laboratories handle a wide range of biological materials that may pose risks to people, animals, or the environment. Although some laboratories are certified or accredited to ISO standards, most countries do not require it. ISO 35001 is an international standard that helps biomedical laboratories identify, assess, control, and prevent biohazard risks. The successful implementation of a Biorisk Management System (BRMS) in the ISO 35001 framework begins with Clause 4, which requires the organization to understand its context to manage risk. Context analysis can be challenging for professionals whose primary expertise lies in biosafety, biosecurity, microbiology, or laboratory science rather than management-system methodologies. Objective: To provide biosafety and biorisk-management professionals with a practical, structured, and scientifically grounded methodology for conducting the organizational context analysis required to implement ISO 35001, Clause 4. Methods and Results: We documented the context analysis for compliance with Clause 4 of the ISO 35001 standard for a high-containment laboratory through a step-by-step process, employing strategic planning tools and identifying stakeholders who influence the laboratory’s activities. We identified political, economic, social, technological, environmental, and legal factors that may affect the objectives of the biosafety risk management system. We identified internal factors (strengths and weaknesses) and external factors (threats and opportunities) to develop strategic responses. We also defined the scope of our BRMS, including the physical, organizational, operational, and personnel-related areas that may influence the system’s objectives. Conclusions: Implementing ISO 35001 begins with an analysis of the organization’s context. By leveraging strategic planning tools, this approach provides a structured roadmap that can serve as a valuable resource for other biomedical laboratories seeking to establish or optimize their own biorisk management systems.

Neutralizing antibody (nAb) assays are essential for evaluating antibody-mediated immune response against SARS-CoV-2, in the context of efficacy and potency of vaccines, as well as population-level surveillance. This study aimed to estimate the associated uncertainty during the validation of two neutralization assays—50% tissue culture infectious dose microneutralization (TCID ₅₀ MN) and fluorescent focus reduction neutralization test (FRNT)—to measure activity of nAbs against SARS-CoV-2 variants of concern (VOCs) within an ISO/IEC 17025:2017 accredited laboratory. Human serum samples were tested against five SARS-CoV-2 variants (Wuhan, BA.2, BA.5, XBB.1, and JN.1) using vesicular stomatitis virus (VSV) pseudotyped viruses. The validation process was based on international guidelines for the suitability and validation of analytical methods. Both assays demonstrated high diagnostic performance to detect neutralizing activity, where FRNT yielded higher sensitivity but greater inter-analyst variability than TCID ₅₀ MN. These results highlight the importance of identifying the level of impact of factors associated with obtaining a result, such as the training of analysts and the standardization of the test. This study establishes a validated framework for nAb quantification in compliance with international standards. The declaration of associated uncertainty to each method, along with sustained internal quality control, strengthens the diagnostic capacity of these assays in clinical research of correlates of protection and immunity induced by vaccination, in addition to reinforcing transparency and regulatory compliance, as critical elements in decision-making.

Low- and middle-income countries face substantial challenges in immunizing against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including high costs, limited access, and insufficient local manufacturing. To address these issues, we developed and locally manufactured the AVX/COVID-12 vaccine using a cost-effective Newcastle disease virus LaSota platform to express a stabilized SARS-CoV-2 spike protein (HexaPro-S). We evaluated the AVX/COVID-12 vaccine in a phase 2/3 parallel-group, double-blind, active-controlled, noninferiority trial with 4056 volunteers, demonstrating its safety, good tolerability, and ability to induce neutralizing antibodies against ancestral SARS-CoV-2 and the Omicron BA.2 and BA.5 variants. It also stimulated interferon-γ–producing CD8 ⁺ T cells and met the World Health Organization’s noninferiority criteria compared to AZ/ChAdOx-1-S. No vaccinated participants experienced severe disease, hospitalization, or death. These findings support the use of AVX/COVID-12 as a booster to help achieve and maintain population immunity while addressing global inequities in vaccine distribution, and it has been approved for adult booster use in Mexico.

Background: An NDV-based vector has been used as a veterinary vaccine and, recently, as a human COVID-19 vaccine. However, data for the potential immune response against the vector in humans are scarce; therefore, it is important to evaluate the levels of antibodies produced. The HI assay is the gold standard for assessing the humoral response against NDV in poultry serum. Objective: Here, the objective was to validate the HI assay against the NDV-vectored vaccine to analyze antibodies in human serum. Methods: First, we standardized the conditions in human sera before validation. Results: The results for analytical performance in terms of selectivity, sensitivity, specificity, and positive and negative predictive values, as well as positive and negative diagnostic reliability, indicate that the assay is highly selective, allowing clear discrimination between positive and negative samples. Regarding repeatability and intermediate precision, we demonstrated that the assay has the precision to obtain consistent results, guaranteeing their reliability and truthfulness. Finally, the results regarding accuracy, linearity, and robustness indicate that the assay is accurate across the evaluated concentration intervals, with a linear correlation between low and high levels, and demonstrate that it is robust and consistent when serum–antigen interaction times are changed. Conclusions: We conclude that the suitability of the analytical method for its intended use is confirmed, guaranteeing the reliability of the results obtained under the established operating conditions.

NDV-based vector has been used as a veterinary vaccine and, recently also for human COVID-19 vaccine; however, data about the potential immune response against vector in humans is scarce, therefore, it is important evaluate levels of antibodies produced. The HI assay is the gold standard for assessing the humoral response against NDV in poultry serum. Here the objective of was validate the HI assay against the NDV-vectored vaccine to analyze antibodies in human serum. First, we standardized conditions in human sera before validation. The results from analytical performance: selectivity, sensitivity, specificity, positive and negative predictive value, as well as positive and negative diagnostic reliability, indicate that the assay is highly selective, as it allows clear discrimination between positive and negative samples. Regarding repeatability and inter-mediate precision, we demonstrated that the assay has precision to obtain consistent results and guarantees their reliability and truthfulness. Finally, the results of accuracy, linearity and robustness, indicate that the assay is accurate at the concentration intervals evaluated with a linear correlation between the low and high level and demonstrated that it is robust and consistent when the serum-antigen interaction times changed. We conclude that the suitability of the analytical method for its intended use is confirmed and guarantees the reliability of the results obtained under the established operating conditions.

Background The urgent need for safe, effective, and economical coronavirus disease 2019 (COVID-19) vaccines, especially for booster campaigns targeting vulnerable populations, prompted the development of the AVX/COVID-12 vaccine candidate. AVX/COVD-12 is based in a Newcastle disease virus La Sota (NDV-LaSota) recombinant viral vector. This vaccine expresses a stabilized version of the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), specifically the ancestral Wuhan strain. The study aimed to assess its safety, immunogenicity, and potential efficacy as an anti-COVID-19 booster vaccine. Methods In a phase II/III clinical trial conducted from November 9, 2022, to September 11, 2023, a total of 4,056 volunteers were enrolled. Participants received an intramuscular booster dose of either AVX/COVID-12 or AZ/ChAdOx-1-S vaccines. Safety, immunogenicity, and potential efficacy were assessed through various measures, including neutralizing antibody titers, interferon (IFN)-γ-producing CD4+ T cells, and CD8+ T cells. The evaluation also involved immunobridging, utilizing the AZ/ChAdOx-1-S vaccine as an active comparator, and monitoring the incidence of COVID-19 cases. Findings The AVX/COVID-12 vaccine induced neutralizing antibodies against both the ancestral SARS-CoV-2 and the BA.2 and BA.5 Omicron variants. The geometric mean ratio of neutralizing antibody titers between individuals immunized with the AVX/COVID-12 vaccine and those with the AZ/ChAdOx-1-S vaccine at 14 days is 0.96, with a confidence interval (CI) of 0.85-1.06. The outcome aligns with the non-inferiority criterion recommended by the World Health Organization (WHO), indicating a lower limit of the CI greater than or equal to 0.67. Induction of IFN-γ-producing CD8+ T cells at day 14 post-immunization was exclusively observed in the AVX/COVID-12 group. Finally, a trend suggested a potentially lower incidence of COVID-19 cases in AVX/COVID-12 boosted volunteers compared to AZ/ChAdOx-1-S recipients. Conclusion The AVX/COVID-12 vaccine proved safe, well-tolerated, and immunogenic. AVX/COVID-12 meets the WHO non-inferiority standard compared to AZ/ChAdOx-1-S. These results strongly advocate for AVX/COVID-12 as a viable booster dose, supporting its utilization in the population.

Background: The global inequity in coronavirus disease 2019 (COVID-19) vaccine distribution, primarily affecting low- and middle-income countries (LMICs), highlights the urgent need for innovative and cost-effective vaccine technologies to address availability disparities. This is crucial for achieving and sustaining widespread immunity and protecting vulnerable populations during future booster campaigns. Methods: To address this need, we conducted a phase II clinical trial evaluating the safety and immunogenicity of the AVX/COVID-12 “Patria” vaccine as a booster dose. The vaccine was administered through both intramuscular (IM) and intranasal (IN) routes to participants who had previously received severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines based on adenoviral technology, inactivated virus, or mRNA technology. The inclusion criterion involved individuals with initial anti-spike IgG titers below 1,200 U/mL, allowing observation of the booster effect induced by vaccination. Results: Immunization with AVX/COVID-12 resulted in a significant (>2.5 times) increase in neutralizing antibodies against the original Wuhan strain and variants of concern (VOCs) such as Alpha, Beta, Delta, and Omicron (BA.2 and BA.5). This immune response was accompanied by cellular interferon-gamma (IFN-γ) production, indicating a robust and multifaceted reaction. Conclusions: The administration of AVX/COVID-12 as a booster dose, whether through IM or IN routes, was safe and well-tolerated. The vaccine extended immune responses not only against the original Wuhan-1 strain but also against various VOCs. Its ability to enhance preexisting immune responses suggests a potential contribution to expanding and sustaining herd immunity within the population.

Cannabidiol (CBD) has been used to treat a variety of cancers and inflammatory conditions with controversial results. In previous work, we have shown that breast cancer MCF-7 cells, selected by their response to inflammatory IL-1β cytokine, acquire a malignant phenotype (6D cells) through an epithelial–mesenchymal transition (EMT). We evaluated CBD as a potential inhibitor of this transition and inducer of reversion to a non-invasive phenotype. It decreased 6D cell viability, downregulating expression of receptor CB1. The CBD blocked migration and progression of the IL-1β-induced signaling pathway IL-1β/IL-1RI/β-catenin, the driver of EMT. Cannabidiol reestablished the epithelial organization lost by dispersion of the cells and re-localized E-cadherin and β-catenin at the adherens junctions. It also prevented β-catenin nuclear translocation and decreased over-expression of genes for ∆Np63α, BIRC3, and ID1 proteins, induced by IL-1β for acquisition of malignant features. Cannabidiol inhibited the protein kinase B (AKT) activation, a crucial effector in the IL-1β/IL-1RI/β-catenin pathway, indicating that at this point there is crosstalk between IL-1β and CBD signaling which results in phenotype reversion. Our 6D cell system allowed step-by-step analysis of the phenotype transition and better understanding of mechanisms by which CBD blocks and reverts the effects of inflammatory IL-1β in the EMT.

The mechanisms behind the induction of malignancy and chemoresistance in breast cancer cells are still not completely understood. Inflammation is associated with the induction of malignancy in different types of cancer and is highlighted as an important factor for chemoresistance. In previous work, we demonstrated that the inflammatory cytokine interleukin 1β (IL-1β)-induced upregulation of genes was associated with chemoresistance in breast cancer cells. Here, we evaluated the participation and the expression profile of TP63 in the induction of resistance to cisplatin. By loss-of-function assays, we identified that IL-1β particularly upregulates the expression of the tumor protein 63 (TP63) isoform ΔNP63α, through the activation of the IL-1β/IL-1RI/β-catenin signaling pathway. Upregulation of ΔNP63α leads to an increase in the expression of the cell survival factors epidermal growth factor receptor (EGFR) and phosphatase 1D (Wip1), and a decrease in the DNA damage sensor, ataxia-telangiectasia mutated (ATM). The participation of these processes in the increase of resistance to cisplatin was confirmed by silencing TP63 expression or by inhibition of the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) activity in the IL-1β/IL-1RI/β-catenin signaling pathway. These data reinforced the importance of an inflammatory environment in the induction of drug resistance in cancer cells and uncovered a molecular mechanism where the IL-1β signaling pathway potentiates the acquisition of cisplatin resistance in breast cancer cells.