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We have developed a single process for producing two key COVID-19 vaccine antigens: SARS-CoV-2 receptor binding domain (RBD) monomer and dimer. These antigens are featured in various COVID-19 vaccine formats, including SOBERANA 01 and the licensed SOBERANA 02, and SOBERANA Plus. Our approach involves expressing RBD (319-541)-His6 in Chinese hamster ovary (CHO)-K1 cells, generating and characterizing oligoclones, and selecting the best RBD-producing clones. Critical parameters such as copper supplementation in the culture medium and cell viability influenced the yield of RBD dimer. The purification of RBD involved standard immobilized metal ion affinity chromatography (IMAC), ion exchange chromatography, and size exclusion chromatography. Our findings suggest that copper can improve IMAC performance. Efficient RBD production was achieved using small-scale bioreactor cell culture (2 L). The two RBD forms - monomeric and dimeric RBD - were also produced on a large scale (500 L). This study represents the first large-scale application of perfusion culture for the production of RBD antigens. We conducted a thorough analysis of the purified RBD antigens, which encompassed primary structure, protein integrity, N-glycosylation, size, purity, secondary and tertiary structures, isoform composition, hydrophobicity, and long-term stability. Additionally, we investigated RBD-ACE2 interactions, in vitro ACE2 recognition of RBD, and the immunogenicity of RBD antigens in mice. We have determined that both the monomeric and dimeric RBD antigens possess the necessary quality attributes for vaccine production. By enabling the customizable production of both RBD forms, this unified manufacturing process provides the required flexibility to adapt rapidly to the ever-changing demands of emerging SARS-CoV-2 variants and different COVID-19 vaccine platforms.

Abstract Background Multimodal rehabilitation allows optimization of functional recovery in surgery patients by reducing the postoperative stress and hospital stay duration, without increasing the morbidity and mortality. It is reportedly successful in other surgical disciplines, and guidelines for its application to gynecological surgery are available; however, most evidence for these guidelines is derived from observational and/or retrospective studies. Therefore, this study aimed to investigate the applicability of an enhanced recovery after surgery (ERAS) protocol in laparoscopic gynecological surgery and its influence on the postoperative stay, morbidity, mortality, and readmission, through a prospective approach. Methods This prospective cohort study was performed on 90 patients who underwent laparoscopic hysterectomy for benign causes from October 2017 to October 2019. Patients in whom the ERAS (ERAS group, n = 30) and traditional (control group, n = 60) protocols were implemented were compared. All patients were followed for 6 months. Results The groups were homogeneous and did not differ significantly with respect to the demographic characteristics (age, ASA score, body mass index), surgical indications, and surgery types. Adherence to the ERAS protocol was over 99%. The postoperative hospital-stay durations were 1.73 days (r = 1–3) and 2.97 days (r = 2–6) in the ERAS and control groups, respectively (p = 0.000). No significant intergroup differences were observed in the rates of complications and readmissions. Conclusions The ERAS protocol is applicable in laparoscopic gynecological surgery and can be implemented with good adherence. This can allow optimization of patient recovery by reducing the hospital stay duration, without increasing the rates of morbidity, mortality, or readmission.

Abstract Background Müllerian adenosarcoma is a rare malignancy. These tumors occur mainly in the uterus, but also in extrauterine locations, usually related to endometriosis. Because of their rarity, there is limited data on optimal management strategies. Case presentation We present a 44-year-old woman with a history of endometriosis who consults for chronic pelvic pain. In the imaging tests, a heterogeneous mass is observed that impresses endometriosis, encompassing the uterus and left appendage. Surgery is performed by finding an extrauterine adenosarcoma that affected the uterus, ovary and bladder wall. Conclusion This is a rare case but should be considered in a patient with atypical clinical characteristics or preoperative pathology, so we show the diagnostic and therapeutic strategies carried out for the resolution of the case.

Despite the cumulative evidence supporting HER3 as a target for antitumor therapies, no agents targeting HER3 have been approved for cancer treatment. Most of the agents evaluated in preclinical and clinical trials have been specific monoclonal antibodies (MAbs), with few examples of active immunotherapy directed against this receptor. However, some cancer vaccine formats may generate polyclonal antibodies (PAbs) that replicate the diverse effector mechanisms of MAbs, including ligand neutralization and receptor degradation. In this study, we developed a protein subunit-based monovalent vaccine candidate targeting the extracellular domain (ECD) of HER3. Immunization of mice with a formulation targeting murine ErbB3-ECD successfully overcome tolerance to this self-antigen, inducing high titers of ErbB3-specific PAbs. The antitumor potential of this formulation and the induced PAbs was demonstrated in vivo and in vitro in an ErbB3-overexpressing 3LL-D122-derived tumor model. The immunogenicity of the HER3-ECD-based vaccine candidate was confirmed by the induction of high titers of HER3-specific PAbs. Consistent with the initial results, HER3-ECD-targeting PAbs were cytotoxic in several human epithelial tumor cell lines and exerted antitumor effects in vivo. These results support the value of HER3 as a tumor antigen and the effector mechanisms of HER3-specific therapeutic MAbs, while suggesting the potential of the proposed vaccine candidate for the treatment of HER3-expressing carcinomas.

Understanding the immune response generated by SARS-CoV-2 is critical for assessing efficient therapeutic protocols and gaining insights into the durability of protective immunity. The current work was aimed at studying the specific humoral responses against SARS-CoV-2 in Cuban COVID-19 convalescents. We developed suitable tools and methods based on ELISA methodology, for supporting this evaluation. Here, we describe the development of an ELISA for the quantification of anti-RBD IgG titers in a large number of samples and a similar test in the presence of NH4SCN as chaotropic agent for estimating the RBD specific antibody avidity. Additionally, a simple and rapid ELISA based on antibody-mediated blockage of the binding RBD-ACE2 was implemented for detecting, as a surrogate of conventional test, the levels of anti-RBD inhibitory antibodies in convalescent sera. In a cohort of 273 unvaccinated convalescents, we identified higher anti-RBD IgG titer (1 : 1,330, p

Objectives: To evaluate a heterologous vaccination scheme in children 3-18 years old (y/o) combining two SARS-CoV-2r- receptor binding domain (RBD)protein vaccines. Methods: A phase I/II open-label, adaptive, and multicenter trial evaluated the safety and immunogenicity of two doses of FINLAY-FR-2 (subsequently called SOBERANA 02) and the third heterologous dose of FINLAY-FR-1A (subsequently called SOBERANA Plus) in 350 children 3-18 y/o in Havana Cuba. Primary outcomes were safety (phase I) and safety/immunogenicity (phase II) measured by anti-RBD immunoglobulin (Ig)G enzyme-linked immunoassay (ELISA), molecular and live-virus neutralization titers, and specific T-cells response. A comparison with adult immunogenicity and predictions of efficacy were made based on immunological results. Results: Local pain was the unique adverse event with frequency >10%, and none was serious neither severe. Two doses of FINLAY-FR-2 elicited a humoral immune response similar to natural infection; the third dose with FINLAY-FR-1A increased the response in all children, similar to that achieved in vaccinated young adults. The geometric mean (GMT) neutralizing titer was 173.8 (95% confidence interval [CI] 131.7; 229.5) vs Alpha, 142 (95% CI 101.3; 198.9) vs Delta, 24.8 (95% CI 16.8; 36.6) vs Beta and 99.2 (95% CI 67.8; 145.4) vs Omicron. Conclusion: The heterologous scheme was safe and immunogenic in children 3-18 y/o. Trial registry: https://rpcec.sld.cu/trials/RPCEC00000374

Las vacunas SOBERANA®02 y SOBERANA® Plus contra el coronavirus tipo 2 causante del síndrome respiratorio agudo severo, recibieron autorización de uso en emergencia por la autoridad reguladora de Cuba, y de inmediato aconteció una campaña de vacunación masiva en población pediátrica, lo que devino en una inminente movilización de centros de vacunación y vigilancia de sus eventos adversos. El Centro de Inmunología Molecular realizó un estudio de farmacovigilancia intensiva que evalúo el cumplimiento del esquema heterólogo con ambas vacunas, su seguridad y la incidencia de casos positivos a COVID-19 en niños y adolescentes después de completar el esquema de inmunización. Desde el 15 de septiembre al 31 de diciembre del 2021, participaron 529 sujetos entre 2 y 18 años de edad, de ambos sexos, sin antecedentes de infección por coronavirus tipo 2 del síndrome respiratorio agudo severo, procedentes de 35 municipios y 12 provincias cubanas, quienes recibieron vacuna SOBERANA®02 (dos dosis) y SOBERANA®Plus (una dosis). Se realizó vigilancia de eventos adversos hasta 30 días después de la última dosis recibida. Se consultó la plataforma informática nacional Higia Andariego para identificar los casos positivos al virus del síndrome respiratorio agudo severo coronavirus 2, hasta 3 meses de haber completado la vacunación. El 98,5% de los participantes completó el esquema de vacunación y en el 6,6% se notificó algún evento adverso con relación consistente a la vacunación. Predominaron las reacciones locales (dolor, eritema, inflamación), sobre las reacciones sistémicas (fatiga y febrícula), de intensidad ligera o moderada. Se logró un elevado cumplimiento del esquema de inmunización, con un perfil de seguridad favorable, los sujetos con esquema completo de inmunización no enfermaron de COVID-19.

Abstract HER-1 and HER-2 are tumor-associated antigens overexpressed in several epithelial tumors, and successfully targeted by therapeutic approaches against cancer. Vaccination with their recombinant extracellular domains has had encouraging results in the pre-clinical setting. As complex humoral responses targeting multiple epitopes within each antigen are the ultimate goal of such active immunotherapy strategies, molecular dissection of the mixture of antibody specificities is required. The current work exploits phage display of antigenic versions of HER-1 and HER-2 domains to accomplish domain-level epitope mapping. Recognition of domains I, III and IV of both antigens by antibodies of immunized mice was shown, indicating diverse responses covering a broad range of antigenic regions. The combination of phage display and site-directed mutagenesis allowed mutational screening of antigen surface, showing polyclonal antibodies’ recognition of mutated receptor escape variants known to arise in patients under the selective pressure of the anti-HER-1 antibody cetuximab. Phage-displayed HER domains have thus the potential to contribute to fine specificity characterization of humoral responses during future development of anti-cancer vaccines.

BackgroundAntitumor therapies targeting HER1/EGFR and HER2, such as monoclonal antibodies (MAbs) and tyrosine-kinase inhibitors (TKIs), have demonstrated a significant clinical benefit, but the emergence of resistance limits long-term efficacy. While secondary HER1 mutations confer tolerance to TKI, compensatory upregulation of HER2 drives resistance to anti-HER1 MAbs, which identifies MAb combinations targeting both receptors as an attractive therapeutic strategy. Nevertheless, toxicity hampers the clinical validation of this approach. Alternatively, cancer vaccines may induce antibodies directed against several antigens with less concern about induced toxicity.MethodsPolyclonal antibodies (PAbs) targeting HER1 and HER2 were induced in mice or rabbits through immunization. Recognition of different epitopes on targets by PAbs was validated by phage-display technology. Receptor downregulation was evaluated by flow cytometry, immunofluorescence, and Western blot. MTT assays assessed cytotoxicity, while the antitumor effect of PAbs was assayed in nude mice.ResultsPAbs promoted degradation of HER1 and HER2 regarding clinical MAbs or their combinations. As a result, inhibition of cytotoxicity on tumor cell lines was improved, even in the presence of oncogenic mutations in HER1, as well as in cetuximab-insensitive cells. Accordingly, the antitumor effect of vaccination-induced PAbs was observed in lung tumor lines representative of sensitivity or resistance to HER1 targeting therapies.ConclusionsImmunization against HER1 and HER2 receptors offers an alternative to passive administration of combinations of MAbs, since vaccination-induced PAbs promote the downregulation of both receptors and they have a higher impact on the survival of tumor cells.

Proteolytic enzymes, also known as peptidases, are critical in all living organisms. Peptidases control the cleavage, activation, turnover, and synthesis of proteins and regulate many biochemical and physiological processes. They are also involved in several pathophysiological processes. Among peptidases, aminopeptidases catalyze the cleavage of the N-terminal amino acids of proteins or peptide substrates. They are distributed in many phyla and play critical roles in physiology and pathophysiology. Many of them are metallopeptidases belonging to the M1 and M17 families, among others. Some, such as M1 aminopeptidases N and A, thyrotropin-releasing hormone-degrading ectoenzyme, and M17 leucyl aminopeptidase, are targets for the development of therapeutic agents for human diseases, including cancer, hypertension, central nervous system disorders, inflammation, immune system disorders, skin pathologies, and infectious diseases, such as malaria. The relevance of aminopeptidases has driven the search and identification of potent and selective inhibitors as major tools to control proteolysis with an impact in biochemistry, biotechnology, and biomedicine. The present contribution focuses on marine invertebrate biodiversity as an important and promising source of inhibitors of metalloaminopeptidases from M1 and M17 families, with foreseen biomedical applications in human diseases. The results reviewed in the present contribution support and encourage further studies with inhibitors isolated from marine invertebrates in different biomedical models associated with the activity of these families of exopeptidases.

Background: As a first step towards a vaccine protecting COVID-19 convalescents from reinfection, we evaluated FINLAY-FR-1A vaccine in a clinical trial. Methods: Thirty COVID-19 convalescents aged 22-57 years were studied: convalescents of mild COVID-19, asymptomatic convalescents, both with PCR-positive at the moment of diagnosis; and individuals with subclinical infection detected by viral-specific IgG. They received a single intramuscular injection of the FINLAY-FR-1A vaccine (50 µg of the recombinant dimeric receptor binding domain). The primary outcomes were safety and reactogenicity, assessed over 28 days after vaccination. The secondary outcome was vaccine immunogenicity. Humoral response at baseline and following vaccination was evaluated by ELISA and live-virus neutralization test. The effector T cellular response was also assessed. Cuban Public Registry of Clinical Trials, WHO-ICTRP: https://rpcec.sld.cu/en/trials/RPCEC00000349-En. Findings: No serious adverse events were reported. Minor adverse events were found, the most common, local pain: 3 (10%) and redness: 2 (6·7%). The vaccine elicited a >21 fold increase in IgG anti-RBD antibodies 28 days after vaccination. The median of inhibitory antibody titres (94·0%) was three times greater than that of the COVID-19 convalescent panel. Virus neutralization titres higher than 1:160 were found in 24 (80%) participants. There was also an increase in RBD-specific T cells producing IFN-γ and TNF-α. Interpretation: A single dose of the FINLAY-FR-1A vaccine against SARS-CoV-2 was an efficient booster of pre-existing natural immunity, with excellent safety profile. Funding: Partial funding for this study was received from the Project-2020-20, Fondo de Ciencia e Innovación (FONCI), Ministry of Science, Technology and the Environment, Cuba.

The epidermal growth factor receptor (EGFR) is highly expressed in many types of epithelial tumors. EGFR overexpression has been associated with an advanced stage of the disease, with resistance to standard therapies, and, for certain tumors, with poor patient prognosis. As a result, EGFR has been considered a meaningful target in anti-tumor strategies. Active and passive immunotherapies blocking EGFR and its ligands have been explored. But for successful pre-clinical evaluation of these approaches, well-established murine tumor models are not available and highly desirable. We described, for the first time, the generation and characterization of an anti-murine EGFR extracellular domain monoclonal antibody (7A7 MAb) (IgG1). 7A7 was generated by immunization of Balb/c mice with the recombinant extracellular domain of murine EGFR (rECD-mEGFR). 7A7 recognized an epitope present in the amino acidic core of the antigen and is cross-reactive with the human EGFR. Interestingly, this MAb was able to specifically bind EGFR at the cell surface, allowing the assessment of its differential expression in a panel of murine cells. Noteworthy, in a preliminary immunohistochemical study with 7A7 MAb, recognition of Balb/c mice skin sections and EGFR-positive tumors were observed. We concluded that 7A7 MAb is a valuable tool for EGFR-based therapeutic pre-clinical studies. [ABSTRACT FROM AUTHOR]

Background: Growth hormone secretagogues (GHS), among other factors, regulate the release of GH. The biological activity of the secretagogue peptide A233 as a promoter of growth and innate immunity in teleost fish has previously been demonstrated, but its role in the immune system of mammals is not well understood. Methods: The effect of the peptide was investigated in J774A.2 macrophage cells using a comparative proteomics approach after 6 and 12 h of peptide stimulation. Results: The functional analysis of differentially modulated proteins showed that A233 peptide treatment appears to promote activation and ROS-dependent cytotoxic functions in macrophages and enhanced expression of antiviral protein complexes such as MAVS. In accordance with this hypothesis, we found that A233 treatment enhanced superoxide anion production and the IFN-γ level in J774A.2 cells and mouse splenocytes, respectively, and reduced viral load in a dengue virus mouse model of infection. Conclusions: The growth hormone secretagogue A233 peptide promotes activation of ROS-dependent cytotoxic functions and exerts immunomodulatory effects that enable an antiviral state in a dengue virus mouse model. General Significance: The increase of IFN-γ level and the differential modulation of antiviral proteins by the A233 peptide suggest that the molecule could activate an innate immune response with a possible further impact in the treatment of acute and chronic diseases.

Defining how epidermal growth factor receptor (EGFR)-targeting therapies influence the immune response is essential to increase their clinical efficacy. A growing emphasis is being placed on immune regulator genes that govern tumor – T cell interactions. Previous studies showed an increase in HLA class I cell surface expression in tumor cell lines treated with anti-EGFR agents. In particular, earlier studies of the anti-EGFR blocking antibody cetuximab, have suggested that increased tumor expression of HLA class I is associated with positive clinical response. We investigated the effect of another commercially available anti-EGFR antibody nimotuzumab on HLA class I expression in tumor cell lines. We observed, for the first time, that nimotuzumab increases HLA class I expression and its effect is associated with a coordinated increase in mRNA levels of the principal antigen processing and presentation components. Moreover, using 7A7 (a specific surrogate antibody against murine EGFR), we obtained results suggesting the importance of the increased MHC-I expression induced by EGFR-targeted therapies display higher in antitumor immune response. 7A7 therapy induced upregulation of tumor MHC-I expression in vivo and tumors treated with this antibody display higher susceptibility to CD8+ T cells-mediated lysis. Our results represent the first evidence suggesting the importance of the adaptive immunity in nimotuzumab-mediated antitumor activity. More experiments should be conducted in order to elucidate the relevance of this mechanism in cancer patients. This novel immune-related antitumor mechanism mediated by nimotuzumab opens new perspectives for its combination with various immunotherapeutic agents and cancer vaccines.

Metastatic castration-resistant prostate cancer (CRPC) remains incurable due to the lack of effective therapies. Activation of the human epidermal growth factor receptor 1 (HER1) in prostate cancer contributes to metastatic progression as well as to disease relapse. Here, we determined the toxicity and immunogenicity of a HER1-based cancer vaccine in CRPC patients included in a phase I clinical trial. CRPC patients (n = 24) were intramuscularly vaccinated with HER1 vaccine consisting of the extracellular domain of HER1 molecule (ECD) and very small size proteoliposome from Neisseria meningitidis (VSSP) and Montanide ISA-51 VG as adjuvants. Patients were included in five groups according to the vaccine dose (100, 200, 400, 600, and 800 μg). The primary endpoints were safety and immunogenicity. The anti-HER1 antibodies were measured by an ELISA, the recognition of an HER1 positive tumor cell line and the inhibition of HER1 phosphorylation by sera were determined by flow cytometry and western blot analysis, respectively. The HER1-specific T cell response was assessed by determination of IFN-γ-producing T cells using ELISpot assay. The vaccine was well tolerated. No grade III or IV adverse events were reported. High titers of anti-HER1 antibodies were observed in most of the evaluated patients. There were no significant differences regarding the geometric means of the anti-HER1 titers among the dose groups except the group of 100 μg in which antibody titers were significantly lower. A Th1-type IgG subclasses pattern was predominant in most patients. Only patients receiving the higher doses of vaccine showed significant tumor cell recognition and HER1 phosphorylation inhibition by hyperimmune sera. Forty two percent of the patients showed a specific T cell response against HER1 peptides pool in post-treatment samples. There was a trend toward survival benefit in those patients showing high anti-HER1 specific antibody titers and a significant association between cellular immune response and clinical outcome.

The expression and production of pharmaceutical, industrial and veterinary proteins in plants is an attractive approach. These expression hosts bear an enormous production potential in terms of volume, easy processing of the starting material, and safety of the final product due to the lack of pathogens able to infect animal and human cells. Antibodies are among the most frequently proteins expressed in plants, subsequently called plantibodies. However, plantibodies are differently glycosylated in plant cells, with oligosaccharide residues being added which may them immunogenic in the final organism. For that reason, several strategies have been developed to genetically modify host plants to mimic the N-glycosylation patterns typical in animal cells. This work was aimed at developing a strategy to obtain a aglycosylated plantibody version of nimotuzumab, the first antibody registered as a product in Cuba for cancer immunotherapy. The strategy comprised the genetic modification of the heavy chain glycosylation site of nimotuzumab, and its expression as an aglycosylated protein in tobacco leaves, by means of developing a transient expression system using Agrobacterium infiltration into tobacco leaves for the initial characterization of the plantibody. It was demonstrated that transgenic plants were capable of producing a plant-derived nimotuzumab antibody which retained the antitumor activity in vitro and in vivo, compared to its glycosylated counterpart produced in mammalian cells. This work demonstrates the potential of transgenic plants to produce aglycosylated therapeutic antibodies for cancer treatment, and won the National Award of the Academy of Sciences of Cuba in 2012.

The Epidermal Growth Factor Receptor (EGFR) plays an essential role in regulating neoplastic processes. EGFR over-expression in many human epithelial tumors has been correlated with disease progression and bad prognosis. Passive EGFR-directed immunotherapy has been introduced in medical oncology practice, but no active specific approaches have been used. We designed a vaccine candidate based on the extracellular domain (ECD) of human EGFR (HER1), and the homologous vaccine for mice based on murine EGFR. This vaccine candidate uses the Very Small-Sized Proteoliposomes from Neisseria meningitidis (VSSP) and Montanide ISA 51-VG as adjuvants. The autologous vaccine circumvents the tolerance to self EGFR by inducing a specific immune response with an anti-metastatic effect on EGFR+ tumors. The vaccine candidate based on HER1-ECD induced anti-EGFR polyclonal antibodies (PAb) that bind EGFR+ human tumor cell lines from different tissues. These anti-EGFR PAb abrogate ligand-dependent EGFR phosphorylation, provoking the inhibition of tumor cell growth and apoptosis. Preclinical results further encouraged the evaluation of the HER1 vaccine candidate in phase I clinical trials

The Epidermal Growth Factor Receptor (EGFR) plays an essential role in regulating neoplastic processes. EGFR over-expression in many human epithelial tumors has been correlated with disease progression and bad prognosis. Passive EGFR-directed immunotherapy has been introduced in medical oncology practice, but no active specific approaches have been used. We designed a vaccine candidate based on the extracellular domain (ECD) of human EGFR (HER1), and the homologous vaccine for mice based on murine EGFR. This vaccine candidate uses the Very Small-Sized Proteoliposomes from Neisseria meningitidis (VSSP) and Montanide ISA 51-VG as adjuvants. The autologous vaccine circumvents the tolerance to self EGFR by inducing a specific immune response with an anti-metastatic effect on EGFR+ tumors. The vaccine candidate based on HER1-ECD induced anti-EGFR polyclonal antibodies (PAb) that bind EGFR+ human tumor cell lines from different tissues. These anti-EGFR PAb abrogate ligand-dependent EGFR phosphorylation, provoking the inhibition of tumor cell growth and apoptosis. Preclinical results further encouraged the evaluation of the HER1 vaccine candidate in phase I clinical trials