Dysfunctional Myelopoiesis and Myeloid-Derived Suppressor Cells in Sepsis

Sepsis participant: Inclusion Criteria: 1. age ≥18 years 2. meets criteria for sepsis/septic shock by Sepsis-3 consensus criteria. Exclusion Criteria: 1. have disease states that predispose to significant immune system dysfunction 2. have comorbidity burden or goals of care that preclude recovery after sepsis. These criteria include: a. irreversible shock (death \<12 hours) b. uncontrollable surgical source of sepsis c. patients deemed to be futile care or have advanced directives limiting resuscitative efforts d. alternative diagnoses causing shock state (e.g., hemorrhage, myocardial infarction or pulmonary embolus) e. known HIV infection with CD4+ count \<200 cells/mm3 g. severe traumatic brain injury with unencumbered assessment of GCS equaling 3 on admission to the intensive care unit. 3. known pregnancy 4. enrollment \>96 hours after suspected sepsis onset 5. pre-hospitalization bedridden performance status (WHO/Zubrod score ≥4) 6. subsequent clinical adjudication diagnosis not consistent with sepsis/septic shock by Sepsis-3 criteria. 7. Burn injury greater than 20% total body surface area (tBSA) Trauma Participant: Inclusion Criteria 1. All adults age ≥ 18 years 2. Blunt trauma patient with a. Injury Severity Score (ISS) greater than or equal to 25 b. ISS \> 15 and one of the following: i. \> 4 units of PRBC or \>3 units of whole blood or \>1500 ml of autogenous blood product in the first 24 hours of admission ii. AIS (acute injury score) \> 2 spine iii. Shock on arrival (Systolic blood pressure (SBP) \< 90) OR c. ISS \> 15 and two of the following: i. Age \> 55 ii. AIS \> 2 chest iii. +ETOH (ethyl alcohol) on arrival iv. Any red blood cell transfusion in first 24 hours Exclusion Criteria 1. Patients not expected to survive greater than 48 hours. 2. Prisoners. 3. Pregnancy. 4. Previous bone marrow transplantation. 5. Patients with End Stage Renal Disease. 6. Patients with any pre-existing hematological disease. 7. Patients deemed to be futile care or have advanced directives limiting resuscitative efforts. 8. Known HIV infection with CD4+ count \<200 cells/mm3 9. Burn injury greater than 20% tBSA