Molecular Modeling Insights into Upadacitinib Selectivity upon Binding to JAK Protein Family

Rheumatoid arthritis (RA) is a chronic disease characterized by bone joint damage and incapacitation. The mechanism underlying RA pathogenesis is autoimmunity in the connective tissue. Cytokines play an important role in the human immune system for signal transduction and in the development of inflammatory responses. Janus kinases (JAK) participate in the JAK/STAT pathway, which mediates cytokine effects, in particular interleukin 6 and IFNγ. The discovery of small molecule inhibitors of the JAK protein family has led to a revolution in RA therapy. The novel JAK inhibitor upadacitinib (RinvoqTM) has a higher selectivity for JAK1 compared to JAK2 and JAK3 in vivo. Currently, details on the molecular recognition of JAK1 by upadacitinib are not available. We found that characteristics of hydrogen bond formation with the glycine loop and hinge in JAKs define the selectivity. Our molecular modeling study could provide insight into the drug action mechanism and pharmacophore model differences in JAK isoforms.

Download Full-text

P06.07 In vivo studies of immunomodulatory a-CTLA-4 antibody in a humanized mouse model

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2021-itoc8.41 ◽

2021 ◽

Vol 9 (Suppl 1) ◽

pp. A22.1-A22

Author(s):

C Reitinger ◽

F Nimmerjahn

Keyword(s):

Immune System ◽

Mouse Model ◽

Cancer Immunotherapy ◽

Model Systems ◽

Checkpoint Control ◽

Human Immune System ◽

Humanized Mouse ◽

Humanized Mouse Model ◽

Human Immune

BackgroundRecent findings in cancer immunotherapy have reinforced the hypothesis that the immune system is able to control most cancers. Immunomodulatory antibodies can enhance immune responses, having the potential to generate anti-cancer immunity.1–4Materials and MethodsMost current studies addressing this question are performed in murine mouse model systems or use in vitro culture systems, which do not reflect the human in vivo situation, potentially leading to results that cannot be fully translated into human cancer therapy. Therefore, it is necessary to establish a new mouse model, which allows the study of cancer immunotherapy in the context of a human immune system. We focused on the establishment of a humanized mouse model, in which different immunomodulatory antibodies can be tested in the presence of a human immune system.ResultsFirst experiments concerning the suitability to test immunomodulatory antibodies in the humanized mouse model, revealed that effects of checkpoint-control antibody a-CTLA-4 were similar to the effects seen in patients of clinical studies. To analyse the anti-tumor activities of immunomodulatory antibodies in vivo we are establishing a human melanoma-like tumor model in humanized mice.ConclusionsThis enables us to test the efficacy of immunomodulatory agonistic antibodies (such as CP-870,893) and checkpoint control antibodies (such as anti-CTLA-4) in eliminating a melanoma-like tumor. Furthermore, parameters like tumor infiltrating human cells und cytokine/chemokine production can be analysed.ReferencesSchuster M, Nechansky A, Loibner H. Cancer immunotherapy. Biotechnol J 2006;1:138–147.Mellman I, Coukos G, Dranoff G. Cancer immunotherapy comes of age. Nature rev 2011;480:480–489.Finn OJ. Immuno-oncology: understanding the function and dysfunction of the immune system in cancer. Annals of Oncology 2012;23:vii6–vii9.Langer LF, Clay TM, Morse MA. Update on anti-CTLA-4 in clinical trials. Expert Opin Biol Ther 2007;8:1245–1256.Disclosure InformationC. Reitinger: None. F. Nimmerjahn: None.

Download Full-text

Immunoinformatic design of a COVID-19 subunit vaccine using entire structural immunogenic epitopes of SARS-CoV-2

Scientific Reports ◽

10.1038/s41598-020-77547-4 ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Esmaeil Behmard ◽

Bijan Soleymani ◽

Ali Najafi ◽

Ebrahim Barzegari

Keyword(s):

A Priori ◽

3D Structure ◽

Free Energy Calculations ◽

Structural Proteins ◽

Toll Like Receptor ◽

Cell Binding ◽

Human Immune System ◽

Human Immune ◽

Dynamics Simulations

AbstractCoronavirus disease 2019 (COVID-19) is an acute pneumonic disease, with no prophylactic or specific therapeutical solution. Effective and rapid countermeasure against the spread of the disease’s associated virus, SARS-CoV-2, requires to incorporate the computational approach. In this study, we employed various immunoinformatics tools to design a multi-epitope vaccine polypeptide with the highest potential for activating the human immune system against SARS-CoV-2. The initial epitope set was extracted from the whole set of viral structural proteins. Potential non-toxic and non-allergenic T-cell and B-cell binding and cytokine inducing epitopes were then identified through a priori prediction. Selected epitopes were bound to each other with appropriate linkers, followed by appending a suitable adjuvant to increase the immunogenicity of the vaccine polypeptide. Molecular modelling of the 3D structure of the vaccine construct, docking, molecular dynamics simulations and free energy calculations confirmed that the vaccine peptide had high affinity for Toll-like receptor 3 binding, and that the vaccine-receptor complex was highly stable. As our vaccine polypeptide design captures the advantages of structural epitopes and simultaneously integrates precautions to avoid relevant side effects, it is suggested to be promising for elicitation of an effective and safe immune response against SARS-CoV-2 in vivo.

Download Full-text

Immunomodulatory Effects of Edible and Medicinal Mushrooms and Their Bioactive Immunoregulatory Products

Journal of Fungi ◽

10.3390/jof6040269 ◽

2020 ◽

Vol 6 (4) ◽

pp. 269

Author(s):

Shuang Zhao ◽

Qi Gao ◽

Chengbo Rong ◽

Shouxian Wang ◽

Zhekun Zhao ◽

...

Keyword(s):

Bioactive Compounds ◽

Immune Modulation ◽

Essential Amino Acids ◽

Current Status ◽

Human Immune System ◽

Mushroom Species ◽

Medicinal Mushrooms ◽

Human Immune

Mushrooms have been valued as food and health supplements by humans for centuries. They are rich in dietary fiber, essential amino acids, minerals, and many bioactive compounds, especially those related to human immune system functions. Mushrooms contain diverse immunoregulatory compounds such as terpenes and terpenoids, lectins, fungal immunomodulatory proteins (FIPs) and polysaccharides. The distributions of these compounds differ among mushroom species and their potent immune modulation activities vary depending on their core structures and fraction composition chemical modifications. Here we review the current status of clinical studies on immunomodulatory activities of mushrooms and mushroom products. The potential mechanisms for their activities both in vitro and in vivo were summarized. We describe the approaches that have been used in the development and application of bioactive compounds extracted from mushrooms. These developments have led to the commercialization of a large number of mushroom products. Finally, we discuss the problems in pharmacological applications of mushrooms and mushroom products and highlight a few areas that should be improved before immunomodulatory compounds from mushrooms can be widely used as therapeutic agents.

Download Full-text

Human NK cells of mice with reconstituted human immune system components require preactivation to acquire functional competence

Blood ◽

10.1182/blood-2010-02-270678 ◽

2010 ◽

Vol 116 (20) ◽

pp. 4158-4167 ◽

Cited By ~ 70

Author(s):

Till Strowig ◽

Obinna Chijioke ◽

Paolo Carrega ◽

Frida Arrey ◽

Sonja Meixlsperger ◽

...

Keyword(s):

Immune System ◽

Cord Blood ◽

Nk Cells ◽

Nk Cell ◽

Human Immune System ◽

Hematopoietic Progenitor ◽

Human Adult ◽

System Components ◽

Human Immune

Abstract To investigate human natural killer (NK)–cell reactivity in vivo we have reconstituted human immune system components by transplantation of human hematopoietic progenitor cells into NOD-scid IL2Rγnull mice. We demonstrate here that this model allows the development of all NK-cell subsets that are also found in human adult peripheral and cord blood, including NKp46+CD56− NK cells. Similar to human cord blood, NK cells from these reconstituted mice require preactivation by interleukin-15 to reach the functional competence of human adult NK cells. Mainly the terminally differentiated CD16+ NK cells demonstrate lower reactivity without this stimulation. After preactivation, both CD16+ and CD16− NK cells efficiently produce interferon-γ and degranulate in response to stimulation with NK cell–susceptible targets, including K562 erythroleukemia cells. NK-cell lines, established from reconstituted mice, demonstrate cytotoxicity against this tumor cell line. Importantly, preactivation can as well be achieved by bystander cell maturation via poly I:C stimulation in vitro and injection of this maturation stimulus in vivo. Preactivation in vivo enhances killing of human leukocyte antigen class I negative tumor cells after their adoptive transfer. These data suggest that a functional, but resting, NK-cell compartment can be established in immune-compromised mice after human hematopoietic progenitor cell transfer.

Download Full-text

Human innate responses and adjuvant activity of TLR ligands in vivo in mice reconstituted with a human immune system

Vaccine ◽

10.1016/j.vaccine.2017.09.052 ◽

2017 ◽

Vol 35 (45) ◽

pp. 6143-6153 ◽

Cited By ~ 21

Author(s):

Liang Cheng ◽

Zheng Zhang ◽

Guangming Li ◽

Feng Li ◽

Li Wang ◽

...

Keyword(s):

Immune System ◽

Human Immune System ◽

Adjuvant Activity ◽

Human Immune

Download Full-text

Tryptophan hydroxylase-1 regulates immune tolerance and inflammation

Journal of Experimental Medicine ◽

10.1084/jem.20120408 ◽

2012 ◽

Vol 209 (11) ◽

pp. 2127-2135 ◽

Cited By ~ 76

Author(s):

Elizabeth C. Nowak ◽

Victor C. de Vries ◽

Anna Wasiuk ◽

Cory Ahonen ◽

Kathryn A. Bennett ◽

...

Keyword(s):

Immune Tolerance ◽

Tryptophan Hydroxylase ◽

Inflammatory Responses ◽

Essential Amino Acids ◽

The Novel ◽

Skin Allograft ◽

Autoimmune Encephalomyelitis ◽

Tumor Remission ◽

Experimental Autoimmune

Nutrient deprivation based on the loss of essential amino acids by catabolic enzymes in the microenvironment is a critical means to control inflammatory responses and immune tolerance. Here we report the novel finding that Tph-1 (tryptophan hydroxylase-1), a synthase which catalyses the conversion of tryptophan to serotonin and exhausts tryptophan, is a potent regulator of immunity. In models of skin allograft tolerance, tumor growth, and experimental autoimmune encephalomyelitis, Tph-1 deficiency breaks allograft tolerance, induces tumor remission, and intensifies neuroinflammation, respectively. All of these effects of Tph-1 deficiency are independent of its downstream product serotonin. Because mast cells (MCs) appear to be the major source of Tph-1 and restoration of Tph-1 in the MC compartment in vivo compensates for the defect, these experiments introduce a fundamentally new mechanism of MC-mediated immune suppression that broadly impacts multiple arms of immunity.

Download Full-text

Stable Engraftment of a Human Gut Bacterial Microbiome in Double Humanized BLT-mice

10.1101/749093 ◽

2019 ◽

Cited By ~ 1

Author(s):

Lance Daharsh ◽

Amanda E. Ramer-Tait ◽

Qingsheng Li

Keyword(s):

Immune System ◽

Gut Microbiome ◽

Human Disease ◽

Humanized Mice ◽

Rrna Gene ◽

Human Immune System ◽

Human Gut ◽

Healthy Human ◽

Human Immune

AbstractBackgroundHumanized mice featuring a functional human immune system are an important pre-clinical model for examining immune responses to human-specific pathogens. This model has been widely utilized to study human diseases that are otherwise impossible or difficult to investigate in humans or with other animal models. However, one limitation of using humanized mice is their native murine gut microbiome, which significantly differs from the one found in humans. These differences may be even greater for mice housed and bred in specific pathogen free conditions. Given the importance of the gut microbiome to human health and disease, these differences may profoundly impact the ability to translate the results from humanized mice studies to human disease. Further, there is a critical need for improved pre-clinical models to study the complex in vivo relationships of the gut microbiome, immune system, and human disease. We therefore created double humanized mice with both a functional human immune system and stable human-like gut microbiome.ResultsSurgery was performed on NOD.Cg-PrkdcscidII2rgtm1Wjl/SzJ (NSG) mice to create bone-marrow, liver, thymus (BLT) humanized mice. After immune reconstitution, mice were treated with broad spectrum antibiotics to deplete murine gut bacteria and then transplanted with fecal material from healthy human donors. Characterization of 173 fecal samples obtained from 45 humanized mice revealed that double humanized mice had unique 16S rRNA gene profiles consistent with those of the individual human donor samples. Importantly, transplanted human-like gut microbiomes were stable in mice for the duration of the study, up to 14.5 weeks post-transplant. Microbiomes of double humanized mice also harbored predicted functional capacities that more closely resembled those of the human donors compared to humanized mice.ConclusionsHere, we describe successful engraftment of a stable human microbiome in BLT humanized mice to further improve this preclinical humanized mouse model. These double humanized mice represent a unique and tractable new model to study the complex relationships between the human gut microbiome, human immune system, and human disease in vivo.

Download Full-text

Building the Next Generation of Humanized Hemato-Lymphoid System Mice

Frontiers in Immunology ◽

10.3389/fimmu.2021.643852 ◽

2021 ◽

Vol 12 ◽

Author(s):

Tijana Martinov ◽

Kelly M. McKenna ◽

Wei Hong Tan ◽

Emily J. Collins ◽

Allie R. Kehret ◽

...

Keyword(s):

Immune System ◽

Adaptive Immunity ◽

Humanized Mice ◽

Human Immune System ◽

Functional Interactions ◽

Life Saving ◽

Mouse Tissues ◽

Fundamental Biology ◽

Human Immune

Since the late 1980s, mice have been repopulated with human hematopoietic cells to study the fundamental biology of human hematopoiesis and immunity, as well as a broad range of human diseases in vivo. Multiple mouse recipient strains have been developed and protocols optimized to efficiently generate these “humanized” mice. Here, we review three guiding principles that have been applied to the development of the currently available models: (1) establishing tolerance of the mouse host for the human graft; (2) opening hematopoietic niches so that they can be occupied by human cells; and (3) providing necessary support for human hematopoiesis. We then discuss four remaining challenges: (1) human hematopoietic lineages that poorly develop in mice; (2) limited antigen-specific adaptive immunity; (3) absent tolerance of the human immune system for its mouse host; and (4) sub-functional interactions between human immune effectors and target mouse tissues. While major advances are still needed, the current models can already be used to answer specific, clinically-relevant questions and hopefully inform the development of new, life-saving therapies.

Download Full-text

Epigenetic promoter alterations in GI tumour immune-editing and resistance to immune checkpoint inhibition

Gut ◽

10.1136/gutjnl-2021-324420 ◽

2021 ◽

pp. gutjnl-2021-324420

Author(s):

Raghav Sundar ◽

Kie-Kyon Huang ◽

Vikrant Kumar ◽

Kalpana Ramnarayanan ◽

Deniz Demircioglu ◽

...

Keyword(s):

Gastric Cancer ◽

T Cell ◽

Checkpoint Inhibition ◽

Immune Checkpoint Inhibition ◽

Human Immune System ◽

Immune Microenvironment ◽

Gastrointestinal Tumours ◽

Alternate Promoter ◽

Human Immune

ObjectivesEpigenomic alterations in cancer interact with the immune microenvironment to dictate tumour evolution and therapeutic response. We aimed to study the regulation of the tumour immune microenvironment through epigenetic alternate promoter use in gastric cancer and to expand our findings to other gastrointestinal tumours.DesignAlternate promoter burden (APB) was quantified using a novel bioinformatic algorithm (proActiv) to infer promoter activity from short-read RNA sequencing and samples categorised into APBhigh, APBint and APBlow. Single-cell RNA sequencing was performed to analyse the intratumour immune microenvironment. A humanised mouse cancer in vivo model was used to explore dynamic temporal interactions between tumour kinetics, alternate promoter usage and the human immune system. Multiple cohorts of gastrointestinal tumours treated with immunotherapy were assessed for correlation between APB and treatment outcomes.ResultsAPBhigh gastric cancer tumours expressed decreased levels of T-cell cytolytic activity and exhibited signatures of immune depletion. Single-cell RNAsequencing analysis confirmed distinct immunological populations and lower T-cell proportions in APBhigh tumours. Functional in vivo studies using ‘humanised mice’ harbouring an active human immune system revealed distinct temporal relationships between APB and tumour growth, with APBhigh tumours having almost no human T-cell infiltration. Analysis of immunotherapy-treated patients with GI cancer confirmed resistance of APBhigh tumours to immune checkpoint inhibition. APBhigh gastric cancer exhibited significantly poorer progression-free survival compared with APBlow (median 55 days vs 121 days, HR 0.40, 95% CI 0.18 to 0.93, p=0.032).ConclusionThese findings demonstrate an association between alternate promoter use and the tumour microenvironment, leading to immune evasion and immunotherapy resistance.

Download Full-text