Inhibition of Interleukin-10 Restores T-cell Function in Patients with Sepsis
CCCF ePoster library. Mazer M. Nov 9, 2018; 233345
Monty Mazer
Monty Mazer
Login now to access Regular content available to all registered users.

You may also access this content "anytime, anywhere" with the Free MULTILEARNING App for iOS and Android
Abstract
Rate & Comment (0)

Introduction

Sepsis, defined as life-threatening organ dysfunction due to a dysregulated host response to infection, is characterized by an initial unbridled inflammatory response followed by a phase of immunosuppression. This immunosuppression is categorized by increased numbers of suppressive regulatory T-cells, apoptosis of B-cells and T-cells, and dysregulation of antigen presenting cells (APCs). Additionally, there is downregulation of pro-inflammatory cytokines and upregulation of inhibitory cytokines including interleukin-10 (IL-10). IL-10 is a potent anti-inflammatory cytokine produced primarily by regulatory T-cells and macrophages. IL-10 downregulates function of activated T cells and macrophages, and reduces expression of MHC Class-II.



Objectives

Previous work in our lab established that both IL-7 and downregulation of the PD1:PD1-ligand (Programmed cell death) axis had immunostimulatory properties. We hypothesize that inhibition of IL-10 alone and in combination with addition of IL7 or anti-PD1 in peripheral blood mononuclear cells (PBMCs) from sepsis patients will restore monocyte and T-cell function and thereby improve crosstalk between innate and adaptive immune systems.



Methods

We enrolled 30 septic and 30 non-septic (control) critically ill patients admitted to the intensive care units (ICU) at a large academic hospital. Blood samples were obtained during early (<72 hours) and later sepsis (>4 days) and patient PBMCs were isolated using density gradient separation. Cells were treated with an anti-IL-10 antibody, IL-7, and anti-PD1. To identify T-cell and monocyte activation, we used ELISpot analysis of IFN-ɣ and TNF-α production respectively. The number of spots compared to control indicates the number of activated cells, and spot size indicates amount of produced cytokine per cell. Cells were also treated with combinations of anti-IL-10 with IL7 and/or anti-PD1. Addition of  rhIL-10 was used to evaluate immunosuppressive effects of IL10.  Finally, we measured stimulatory and inhibitory receptor ligands and HLA-DR expression using flow cytometry. Results were analyzed using t-test and ANOVA.   



Results

Inhibition of IL-10 increased the number of TNF-α producing monocytes as well as the amount of TNF-α produced per cell (fig 1c). When PD1 was blocked in combination with IL-10 inhibition, there was an additive effect in number of cells which produced TNF-α. IL-10 inhibition combined with IL-7 increased the number of cells producing TNF-α as well as spot size (fig 1c+d). There was a subset of patients in the cohort who did not respond to these in vitro treatments. Previous studies in our lab showed that IL-7 significantly increases T-cell activity in-vitro by inducing production of IFN-ɣ, although a subset of patients were non-responders. When IL-10 was blocked in combination with IL-7, there was an increased number of responders, with an increase in IFN-ɣ producing cells (fig 1a+b). The addition of recombinant human IL-10 to septic patient PMBCs did not further inhibit production of TNF-α or IFN-ɣ when compared with controls.



Conclusions

Inhibition of IL-10 restores the innate immune system through increased monocyte production of TNF- α. Inhibition of IL-10 in combination with other immunomodulating therapies has the potential to improve crosstalk between the innate and adaptive immune system and reverse the suppressive effects of sepsis. It will be important to characterize the difference between responders and non-responders.


    This eLearning portal is powered by:
    This eLearning portal is powered by MULTIEPORTAL
Anonymous User Privacy Preferences

Strictly Necessary Cookies (Always Active)

MULTILEARNING platforms and tools hereinafter referred as “MLG SOFTWARE” are provided to you as pure educational platforms/services requiring cookies to operate. In the case of the MLG SOFTWARE, cookies are essential for the Platform to function properly for the provision of education. If these cookies are disabled, a large subset of the functionality provided by the Platform will either be unavailable or cease to work as expected. The MLG SOFTWARE do not capture non-essential activities such as menu items and listings you click on or pages viewed.


Performance Cookies

Performance cookies are used to analyse how visitors use a website in order to provide a better user experience.


Save Settings