scholarly journals Discovery of amino acid variants in the human glucose-dependent insulinotropic polypeptide (GIP) receptor: the impact on the pancreatic beta cell responses and functional expression studies in Chinese hamster fibroblast cells

Diabetologia ◽  
1998 ◽  
Vol 41 (10) ◽  
pp. 1194-1198 ◽  
Author(s):  
K. Almind ◽  
L. Ambye ◽  
S. A. Urhammer ◽  
T. Hansen ◽  
S. M. Echwald ◽  
...  
1996 ◽  
Vol 24 (2) ◽  
pp. S261-S263 ◽  
Author(s):  
Yuji Kawamura ◽  
Yuko Saito ◽  
Mikiro Imamura ◽  
John P. Modderman

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Dominique Lison ◽  
Saloua Ibouraadaten ◽  
Sybille van den Brule ◽  
Milica Todea ◽  
Adriana Vulpoi ◽  
...  

Abstract Background In vitro models are widely used in nanotoxicology. In these assays, a careful documentation of the fraction of nanomaterials that reaches the cells, i.e. the in vitro delivered dose, is a critical element for the interpretation of the data. The in vitro delivered dose can be measured by quantifying the amount of material in contact with the cells, or can be estimated by applying particokinetic models. For carbon nanotubes (CNTs), the determination of the in vitro delivered dose is not evident because their quantification in biological matrices is difficult, and particokinetic models are not adapted to high aspect ratio materials. Here, we applied a rapid and direct approach, based on femtosecond pulsed laser microscopy (FPLM), to assess the in vitro delivered dose of multi-walled CNTs (MWCNTs). Methods and results We incubated mouse lung fibroblasts (MLg) and differentiated human monocytic cells (THP-1) in 96-well plates for 24 h with a set of different MWCNTs. The cytotoxic response to the MWCNTs was evaluated using the WST-1 assay in both cell lines, and the pro-inflammatory response was determined by measuring the release of IL-1β by THP-1 cells. Contrasting cell responses were observed across the MWCNTs. The sedimentation rate of the different MWCNTs was assessed by monitoring turbidity decay with time in cell culture medium. These turbidity measurements revealed some differences among the MWCNT samples which, however, did not parallel the contrasting cell responses. FPLM measurements in cell culture wells revealed that the in vitro delivered MWCNT dose did not parallel sedimentation data, and suggested that cultured cells contributed to set up the delivered dose. The FPLM data allowed, for each MWCNT sample, an adjustment of the measured cytotoxicity and IL-1β responses to the delivered doses. This adjusted in vitro activity led to another toxicity ranking of the MWCNT samples as compared to the unadjusted activities. In macrophages, this adjusted ranking was consistent with existing knowledge on the impact of surface MWCNT functionalization on cytotoxicity, and might better reflect the intrinsic activity of the MWCNT samples. Conclusion The present study further highlights the need to estimate the in vitro delivered dose in cell culture experiments with nanomaterials. The FPLM measurement of the in vitro delivered dose of MWCNTs can enrich experimental results, and may refine our understanding of their interactions with cells.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A317-A317
Author(s):  
Dobrin Draganov ◽  
Antonio Santidrian ◽  
Ivelina Minev ◽  
Duong Nguyen ◽  
Dmitriy Zamarin ◽  
...  

BackgroundThe development of oncolytic viruses for the treatment of cancer has been significantly hampered by their rapid clearance in circulation due to complement and antibody-mediated neutralization. In our recent first-in-human Phase I clinical trial, we evaluated the safety and feasibility of our approach to enhance virus delivery and improve tumor targeting by utilizing an autologous stromal vascular fraction (SVF) based cell delivery system. Patient sample analysis demonstrated that patients could be stratified based on the level of vaccinia virus amplification in vivo, as evidenced by analysis of persistent viral DNA in the blood.MethodsIn the current study, we evaluated the immunomodulatory potential of vaccinia virus delivered by autologous stromal vascular fraction (SVF)-derived cells and attempted to identify immunological correlates of successful vaccinia virus amplification in vivo. To this end, we performed an extensive time-course analysis of cytokines in patients‘ plasma as well as various peripheral blood immune subpopulations using Luminex multi-analyte profiling and multiparameter flow cytometry, respectively. We also analyzed the impact of this therapeutic approach on the innate and adaptive immune subpopulations, including NK cells, myeloid cells, as well as effector, regulatory and memory T cells.ResultsTherapy with SFV-delivered oncolytic vaccinia virus induced a coordinated activation of cytokine, T cell and NK cell responses in patients as early as 1 day after treatment, which peaked around 1-week and lasted for up to 1-month post treatment. The ability of the oncolytic virus to effectively amplify in cancer patients correlated with significant changes of multiple innate (NK) and adaptive (T cell) immunological parameters. Interestingly, patient stratification into groups with transient versus persistent viral DNA was linked to opposing and mutually exclusive patterns of robust activation of NK versus T cell responses, respectively. Our study also identified intriguing cytokine and immune subset frequency signatures present at baseline and associated with successful amplification and persistence of oncolytic vaccinia virus in vivo.ConclusionsOverall, this study establishes the timeline of treatment-related immunological changes and identifies biomarkers present at baseline and potential immunological correlates associated with the persistence of virus amplification in vivo. Therefore, our findings provide new insights into the role of interpatient immunological variability and will contribute to the proper evaluation of the therapeutic potency of oncolytic virotherapy in future clinical trials.


2018 ◽  
Vol 92 (16) ◽  
Author(s):  
Pritesh Desai ◽  
Vikas Tahiliani ◽  
Georges Abboud ◽  
Jessica Stanfield ◽  
Shahram Salek-Ardakani

ABSTRACTRespiratory infection with vaccinia virus (VacV) elicits robust CD8+T cell responses that play an important role in host resistance. In the lung, VacV encounters multiple tissue-resident antigen-presenting cell (APC) populations, but which cell plays a dominant role in priming of virus-specific CD8+effector T cell responses remains poorly defined. We used Batf3−/−mice to investigate the impact of CD103+and CD8α+dendritic cell (DC) deficiency on anti-VacV CD8+T cell responses. We found that Batf3−/−mice were more susceptible to VacV infection, exhibiting profound weight loss, which correlated with impaired accumulation of gamma interferon (IFN-γ)-producing CD8+T cells in the lungs. This was largely due to defective priming since early in the response, antigen-specific CD8+T cells in the draining lymph nodes of Batf3−/−mice expressed significantly reduced levels of Ki67, CD25, and T-bet. These results underscore a specific role for Batf3-dependent DCs in regulating priming and expansion of effector CD8+T cells necessary for host resistance against acute respiratory VacV infection.IMPORTANCEDuring respiratory infection with vaccinia virus (VacV), a member ofPoxviridaefamily, CD8+T cells play important role in resolving the primary infection. Effector CD8+T cells clear the virus by accumulating in the infected lungs in large numbers and secreting molecules such as IFN-γ that kill virally infected cells. However, precise cell types that regulate the generation of effector CD8+T cells in the lungs are not well defined. Dendritic cells (DCs) are a heterogeneous population of immune cells that are recognized as key initiators and regulators of T-cell-mediated immunity. In this study, we reveal that a specific subset of DCs that are dependent on the transcription factor Batf3 for their development regulate the magnitude of CD8+T cell effector responses in the lungs, thereby providing protection during pulmonary VacV infection.


PLoS ONE ◽  
2014 ◽  
Vol 9 (12) ◽  
pp. e115433 ◽  
Author(s):  
Donna L. Nile ◽  
Audrey E. Brown ◽  
Meutia A. Kumaheri ◽  
Helen R. Blair ◽  
Alison Heggie ◽  
...  

2015 ◽  
Vol 89 (20) ◽  
pp. 10303-10318 ◽  
Author(s):  
Justine E. Sunshine ◽  
Brendan B. Larsen ◽  
Brandon Maust ◽  
Ellie Casey ◽  
Wenje Deng ◽  
...  

ABSTRACTTo understand the interplay between host cytotoxic T-lymphocyte (CTL) responses and the mechanisms by which HIV-1 evades them, we studied viral evolutionary patterns associated with host CTL responses in six linked transmission pairs. HIV-1 sequences corresponding to full-length p17 and p24gagwere generated by 454 pyrosequencing for all pairs near the time of transmission, and seroconverting partners were followed for a median of 847 days postinfection. T-cell responses were screened by gamma interferon/interleukin-2 (IFN-γ/IL-2) FluoroSpot using autologous peptide sets reflecting any Gag variant present in at least 5% of sequence reads in the individual's viral population. While we found little evidence for the occurrence of CTL reversions, CTL escape processes were found to be highly dynamic, with multiple epitope variants emerging simultaneously. We found a correlation between epitope entropy and the number of epitope variants per response (r= 0.43;P= 0.05). In cases in which multiple escape mutations developed within a targeted epitope, a variant with no fitness cost became fixed in the viral population. When multiple mutations within an epitope achieved fitness-balanced escape, these escape mutants were each maintained in the viral population. Additional mutations found to confer escape but undetected in viral populations incurred high fitness costs, suggesting that functional constraints limit the available sites tolerable to escape mutations. These results further our understanding of the impact of CTL escape and reversion from the founder virus in HIV infection and contribute to the identification of immunogenic Gag regions most vulnerable to a targeted T-cell attack.IMPORTANCERapid diversification of the viral population is a hallmark of HIV-1 infection, and understanding the selective forces driving the emergence of viral variants can provide critical insight into the interplay between host immune responses and viral evolution. We used deep sequencing to comprehensively follow viral evolution over time in six linked HIV transmission pairs. We then mapped T-cell responses to explore if mutations arose due to adaption to the host and found that escape processes were often highly dynamic, with multiple mutations arising within targeted epitopes. When we explored the impact of these mutations on replicative capacity, we found that dynamic escape processes only resolve with the selection of mutations that conferred escape with no fitness cost to the virus. These results provide further understanding of the complicated viral-host interactions that occur during early HIV-1 infection and may help inform the design of future vaccine immunogens.


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