Distribution and differentiation of myeloid-derived suppressor cells after fluid resuscitation in mice with hemorrhagic shock

Abstract

Abstract:Objective: To investigate the distribution and differentiation of myeloid-derived suppressor cells (MDSCs) in hemorrhagic shock mice, which are resuscitated with normal saline (NS), hypertonic saline (HTS), and hydroxyethyl starch (HES). Methods: BALB/c mice were randomly divided into control, NS, HTS, and HES resuscitation groups. Three subgroups (n=8) in each resuscitation group were marked as 2, 24, and 72 h. Flow cytometry was used to detect the MDSCs, monocytic MDSCs (M-MDSCs), and granulocytic/neutrophilic MDSCs (G-MDSCs) in peripheral blood nucleated cells (PBNCs), spleen single-cell suspension, and bone marrow nucleated cells (BMNCs). Results: The MDSCs in BMNCs among three resuscitation groups were lower 2 h after shock, in PBNCs of the HTS group were higher, and in spleen of the NS group were lower (all P<0.05 vs. control). The M-MDSC/G-MDSC ratios in PBNCs of the HTS and HES groups were lower (both P<0.05 vs. control). At 24 h, the MDSCs in PBNCs of the NS and HTS groups were higher, while the spleen MDSCs in the HTS group were higher (all P<0.05 vs. control). The M-MDSC/ G-MDSC ratios were all less in PBNCs, spleen, and BMNCs of the NS and HTS groups, and were lower in BMNCs of the HES group (all P<0.05 vs. control). At 72 h, the elevated MDSCs in PBNCs were presented in the HTS and HES groups, and in spleen the augment turned up in three resuscitation groups (all P<0.05 vs. control). The inclined ratios to M-MDSC were exhibited in spleen of the NS and HTS groups, and in PBNCs of the NS group; the inclination to G-MDSC in BMNCs was shown in the HES group (all P<0.05 vs. control). Conclusions: HTS induces the earlier elevation of MDSCs in peripheral blood and spleen, and influences its distribution and differentiation, while HES has a less effect on the distribution but a stronger impact on the differentiation of MDSCs, especially in bone marrow.

Early Activation of Myeloid-Derived Suppressor Cells Participate in Sepsis-Induced Immune Suppression via PD-L1/PD-1 Axis

“…The major populations of MDSCs can be divided into two large groups: polymorphonuclear (PMN-MDSC) and monocytic (M-MDSC), which use different mechanisms to suppress immune responses ( 20 ). Our previous study demonstrated that MDSCs declined after hemorrhagic shock, but increased gradually after fluid resuscitation, and the ratio of M-MDSC to PMN-MDSC decreased after 24 h fluid resuscitation, but increased later ( 21 ). However, the distribution and differentiation of the subsets of MDSCs after sepsis are not well-known and few studies have demonstrated the expression of PD-L1 on MDSCs and the subsets during sepsis.…”

Neuroendocrine Modulation of the Immune Response after Trauma and Sepsis: Does It Influence Outcome?

“…Based on these observations, the modulation of MDSC function by systemic steroids may represent a new therapeutic target, although detailed data on the timing of use and type of steroid are still lacking. Furthermore, the function of MDSC in sepsis and trauma has not been sufficiently studied [ 105 , 106 ]. The vast majority of data are based on studies in tumors, although an increasing number of studies highlight the role of MDSC subtypes in the resolution of inflammation after severe sepsis and trauma [ 106 , 107 ].…”

Effect of miR-21-3p on lung injury in rats with traumatic hemorrhagic shock resuscitated with sodium bicarbonate Ringer’s solution

“…Lung injury may develop into acute respiratory distress syndrome (ARDS) and is one of the main causes of death of THS (4). Lung injury after THS is characterized by an excessive uncontrolled inflammatory response and vascular endothelial injury (5)(6)(7). Thus, the reduction of the pulmonary inflammatory response and vascular endothelial injury are important in improving the curative effect of THS.…”