IFNβ (recombinant interferon Beta) has been widely used for the treatment of Multiple sclerosis for the last four decades. Despite the human origin of the IFNβ sequence, IFNβ is immunogenic, and ...unwanted immune responses in IFNβ-treated patients may compromise its efficacy and safety in the clinic. In this study, we applied the DeFT (De-immunization of Functional Therapeutics) approach to producing functional, de-immunized versions of IFNβ-1a. Two de-immunized versions of IFNβ-1a were produced in CHO cells and designated as IFNβ-1a(VAR1) and IFNβ-1a(VAR2). First, the secondary and tertiary protein structures were analyzed by circular dichroism spectroscopy. Then, the variants were also tested for functionality. While IFNβ-1a(VAR2) showed similar in vitro antiviral activity to the original protein, IFNβ-1a(VAR1) exhibited 40% more biological potency. Finally, in vivo assays using HLA-DR transgenic mice revealed that the de-immunized variants showed a markedly reduced immunogenicity when compared to the originator.
Immune responses to protein and peptide drugs can alter or reduce their efficacy and may be associated with adverse effects. While anti-drug antibodies (ADA) are a standard clinical measure of ...protein therapeutic immunogenicity, T cell epitopes in the primary sequences of these drugs are the key drivers or modulators of ADA response, depending on the type of T cell response that is stimulated (e.g., T helper or Regulatory T cells, respectively). In a previous publication on T cell-dependent immunogenicity of biotherapeutics, we addressed mitigation efforts such as identifying and reducing the presence of T cell epitopes or T cell response to protein therapeutics prior to further development of the protein therapeutic for clinical use. Over the past 5 years, greater insight into the role of regulatory T cell epitopes and the conservation of T cell epitopes with self (beyond germline) has improved the preclinical assessment of immunogenic potential. In addition, impurities contained in therapeutic drug formulations such as host cell proteins have also attracted attention and become the focus of novel risk assessment methods. Target effects have come into focus, given the emergence of protein and peptide drugs that target immune receptors in immuno-oncology applications. Lastly, new modalities are entering the clinic, leading to the need to revise certain aspects of the preclinical immunogenicity assessment pathway. In addition to drugs that have multiple antibody-derived domains or non-antibody scaffolds, therapeutic drugs may now be introduced via viral vectors, cell-based constructs, or nucleic acid based therapeutics that may, in addition to delivering drug, also prime the immune system, driving immune response to the delivery vehicle as well as the encoded therapeutic, adding to the complexity of assessing immunogenicity risk. While it is challenging to keep pace with emerging methods for the preclinical assessment of protein therapeutics and new biologic therapeutic modalities, this collective compendium provides a guide to current best practices and new concepts in the field.
Influenza vaccines of H7N9 subtype are consistently less immunogenic in humans than vaccines developed for other subtypes. Although prior immunoinformatic analysis identified T-cell epitopes in H7 ...hemagglutinin (HA) which potentially enhance regulatory T cell response due to conservation with the human genome, the links between the T-cell epitopes and low immunogenicity of H7 HA remains unknown due to the lack of animal models reproducing the response observed in humans. Here, we utilized a humanized mouse model to recapitulate the low immunogenicity of H7 HA. Our analysis demonstrated that modification of a single H7 epitope by changing 3 amino acids so that it is homologous with a known H3 immunogenic epitope sequence significantly improved the immunogenicity of the H7 HA in the humanized mouse model, leading to a greater than 4-fold increase in HA-binding IgG responses. Thus, we provide experimental evidence for the important contribution of this H7-specific T cell epitope in determining the immunogenicity of an influenza vaccine. Furthermore, this study delineates strategies that can be used for screening and selecting vaccine strains using immunoinformatics tools and a humanized mouse model.
Abstract Protein therapeutics hold a prominent and rapidly expanding place among medicinal products. Purified blood products, recombinant cytokines, growth factors, enzyme replacement factors, ...monoclonal antibodies, fusion proteins, and chimeric fusion proteins are all examples of therapeutic proteins that have been developed in the past few decades and approved for use in the treatment of human disease. Despite early belief that the fully human nature of these proteins would represent a significant advantage, adverse effects associated with immune responses to some biologic therapies have become a topic of some concern. As a result, drug developers are devising strategies to assess immune responses to protein therapeutics during both the preclinical and the clinical phases of development. While there are many factors that contribute to protein immunogenicity, T cell- (thymus-) dependent (Td) responses appear to play a critical role in the development of antibody responses to biologic therapeutics. A range of methodologies to predict and measure Td immune responses to protein drugs has been developed. This review will focus on the Td contribution to immunogenicity, summarizing current approaches for the prediction and measurement of T cell-dependent immune responses to protein biologics, discussing the advantages and limitations of these technologies, and suggesting a practical approach for assessing and mitigating Td immunogenicity.
Protein therapeutics, such as monoclonal antibodies, enzymes and toxins, hold significant promise for improving human health. However, repeated administration of protein therapeutics, whether natural ...or recombinant, often leads to the induction of undesirable anti-drug antibodies (ADAs), which interfere with or neutralize the effect of the drug. Although an immune response to foreign proteins can be expected and is well understood, the basis for the development of responses to therapeutic autologous proteins is the subject of some debate. Inflammatory components of the drug delivery vehicle, T cell responses, T and B cell epitopes in the protein drug, and the associated B cell response are all targets for interventions aimed at reducing ADA responses. Here, we review some theories put forward to explain the immunogenicity of therapeutic proteins and describe some emerging protein-engineering approaches that might prevent the development of anti-drug antibodies.
Although screening for pre-cancerous cervical lesions and human papilloma virus (HPV) vaccination are accepted and effective means to prevent cervical cancer, women in Mali have limited access to ...these interventions. In addition, cervical cancer prevention by HPV vaccination has been controversial in some settings. To reduce cervical cancer prevalence and increase HPV vaccine uptake, it is important to understand the level of knowledge about cervical cancer screening and practices related to vaccination in at-risk populations. In this study, the level of knowledge about HPV and cervical cancer and attitudes towards vaccination were assessed among 301 participants (male and female, adults and adolescents) in a house-to-house survey in two urban neighborhoods in Bamako, Mali. The survey was combined with a brief educational session on HPV. Prior to the education session, overall knowledge of HPV infection and cervical cancer was very low: only 8% knew that HPV is a sexually transmitted infection (STI). Less than 20% of women had ever consulted a gynecologist and less than 3% had ever had cervical cancer screening. After hearing a description of HPV vaccine, more than 80% would accept HPV vaccination; fathers and husbands were identified as primary decisions makers and local clinics or the home as preferred sites for vaccination. This study provides information on STI knowledge and vaccine acceptance in Bamako, Mali in 2012, prior to the introduction of HPV vaccination.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The field of cancer therapy has undergone a major transformation in less than a decade due to the introduction of checkpoint inhibitors, the advent of next generation sequencing and the discovery of ...neoantigens. The key observation that the breadth of each patient's immune response to the unique mutations or neoantigens present in their tumor is directly related to their survival has led oncologists to focus on driving immune responses to neoantigens through vaccination. Oncology has entered the era of precision immunotherapy, and cancer vaccine development is undergoing a paradigm shift.
Neoantigens are short peptide sequences found in tumors, but not noncancerous tissues, the vast majority of which are unique to each patient. In addition to providing a description of the distinguishing features of neoantigen discovery platforms, this review will address cross-cutting personalized cancer vaccine design themes and developmental stumbling blocks.
Immunoinformatic pipelines that can rapidly scan cancer genomes and identify 'the best' neoantigens are in high demand. Despite the need for such tools, immunoinformatic methods for identifying neoepitopes in cancer genomes are diverse and have not been well-validated. Validation of 'personalized vaccine design pipelines' will bring about a revolution in neoantigen-based vaccine design and delivery.
Computational vaccinology includes epitope mapping, antigen selection, and immunogen design using computational tools. Tools that facilitate the
prediction of immune response to biothreats, emerging ...infectious diseases, and cancers can accelerate the design of novel and next generation vaccines and their delivery to the clinic. Over the past 20 years, vaccinologists, bioinformatics experts, and advanced programmers based in Providence, Rhode Island, USA have advanced the development of an integrated toolkit for vaccine design called iVAX, that is secure and user-accessible by internet. This integrated set of immunoinformatic tools comprises algorithms for scoring and triaging candidate antigens, selecting immunogenic and conserved T cell epitopes, re-engineering or eliminating regulatory T cell epitopes, and re-designing antigens to induce immunogenicity and protection against disease for humans and livestock. Commercial and academic applications of iVAX have included identifying immunogenic T cell epitopes in the development of a T-cell based human multi-epitope Q fever vaccine, designing novel influenza vaccines, identifying cross-conserved T cell epitopes for a malaria vaccine, and analyzing immune responses in clinical vaccine studies. Animal vaccine applications to date have included viral infections of pigs such as swine influenza A, PCV2, and African Swine Fever. "Rapid-Fire" applications for biodefense have included a demonstration project for Lassa Fever and Q fever. As recent infectious disease outbreaks underscore the significance of vaccine-driven preparedness, the integrated set of tools available on the iVAX toolkit stand ready to help vaccine developers deliver genome-derived, epitope-driven vaccines.
Clinical trials of personalized cancer vaccines have shown that on-demand therapies that are manufactured for each patient, result in activated T cell responses against individual tumor neoantigens. ...However, their use has been traditionally restricted to adjuvant settings and late-stage cancer therapy. There is growing support for the implementation of PCV earlier in the cancer therapy timeline, for reasons that will be discussed in this review.
The efficacy of cancer vaccines may be to some extent dependent on treatment(s) given prior to vaccine administration. Tumors can undergo radical immunoediting following treatment with immunotherapies, such as checkpoint inhibitors, which may affect the presence of the very mutations targeted by cancer vaccines. This review will cover the topics of neoantigen cancer vaccines, tumor immunoediting, and therapy timing.
Therapy timing remains a critical topic to address in optimizing the efficacy of personalized cancer vaccines. Most personalized cancer vaccines are being evaluated in late-stage cancer patients and after treatment with checkpoint inhibitors, but they may offer a greater benefit to the patient if administered in earlier clinical settings, such as the neoadjuvant setting, where patients are not facing T cell exhaustion and/or a further compromised immune system.
As US Hispanic populations are at higher risk than non-Hispanics for cardiovascular disease and Type 2 diabetes targeted interventions are clearly needed. This paper presents the four years results ...of the Vida Sana Program (VSP), which was developed and is implemented by a small clinic serving mostly Spanish-speaking, limited literacy population.
The eight-week course of interactive two-hour sessions taught by Navegantes, bilingual/cultural community health workers, was delivered to participants with hypertension, or high lipids, BMI, waist circumference, glucose or hemoglobin A1C (A1C). Measures, collected by Navegantes and clinic nurses, included blood chemistries, blood pressure, anthropometry, and an assessment of healthy food knowledge.
Most participants (67%) were female, Hispanic (95%), and all were 18 to 70 years of age. At baseline, close to half of participants were obese (48%), had high waist circumference (53%), or elevated A1C (52%), or fasting blood glucose (57%). About one third had high blood pressure (29%) or serum cholesterol (35%), and 22% scored low on the knowledge assessment. After the intervention, participants decreased in weight (-1.0 lb), BMI (-0.2 kg/m2), WC (-0.4 inches), and cholesterol (-3.5 mg/dl, all p<0.001). Systolic blood pressure decreased (-1.7 mm Hg, p<0.001), and the knowledge score increased (6.8 percent, p<0.001).
VSP shows promising improvements in metabolic outcomes, similar to other programs with longer duration or higher intensity interventions. VSP demonstrates an important model for successful community-connected interventions.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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