Transfusion of 35‐day‐stored red blood cells does not alter lipopolysaccharide tolerance during human endotoxemia

Abstract

BACKGROUND: Transfusion-related immunomodulation (TRIM) encompasses immunosuppressive and proinflammatory effects induced by red blood cell (RBC) transfusion. Changes that occur during storage in the RBC product have been hypothesized to underlie TRIM, mediated by tolerance of toll-like receptors (TLR). We investigated whether transfusion of 35-day-stored autologous RBCs alters cytokine production in response to stimulation with lipopolysaccharide (LPS) or lipotheic acid (LTA), in a clinically relevant model of endotoxemia. STUDY DESIGN AND METHODS:Eighteen volunteers received 2 ng/kg LPS intravenously, followed by normal saline or 2-or 35-day-stored autologous RBC transfusion. Before LPS, before transfusion, and 6 hours after transfusion blood was collected to measure cytokine gene expression. Whole blood was used for ex vivo stimulation with LPS and LTA, after which cytokine levels were measured with enzyme-linked immunosorbent assay. RESULTS:In vivo LPS induced a biphasic response in cytokine mRNA with peak values 2 hours after LPS infusion. Storage time of RBC transfusion did not influence cytokine mRNA levels. In vivo infusion of LPS resulted in tolerance for ex vivo stimulation with LPS and LTA. However, transfusion of either fresh or stored RBCs did not further affect the capacity to produce cytokines after ex vivo stimulation. CONCLUSION:In a clinically relevant model of human endotoxemia, autologous transfusion of 35-day-stored RBCs does not influence cytokine mRNA levels nor does it change the capacity of white blood cells in whole blood to produce cytokines after ex vivo stimulation with LPS or LTA. License, which permits use and distribution in any medium, provided the original work is properly cited, the use is noncommercial and no modifications or adaptations are made. MATERIALS AND METHODSAll procedures have been reviewed and approved by the Academic Medical Center Medical Ethical Committee and are according to the Declaration of Helsinki including good clinical practice. The study has been registered at the Dutch Trial Register (NTR4455). All enrolled volunteers provided written informed consent before enrollment. Subjects and designThis study is part of a larger study on the influence of storage time of RBCs on transfusion-related acute lung injury. 21 In short, a total of 18 healthy volunteers, ages 18 to 35 years old, were included in our open-label randomized controlled study. Volunteers were screened at the Academic Medical Center. To be included an unremarkable medical history as well as physical examination was required. Participants were not allowed to participate in another intervention trial during the course of our study. Randomization and blood donationVolunteers were randomly assigned into one of three groups: six volunteers received 2-day-stored (fresh) autologous RBC transfusion, six received 35-day-stored (stored) autologous RBC transfusion, and six volunteers were infused with 350 mL of 0.9% NaCl as endotoxemic control. Depending on group allocation, the volunteers donated 1 uni...

Transfusion-related immunomodulation: a reappraisal

“…This suggests the testable hypothesis of whether pathologically increased erythrophagocytosis can “train” macrophages and monocytes. In the context of TRIM, one hypothesis would be whether increased erythrophagocytosis by macrophages or monocytes induces epigenetic and/or metabolic “immunosuppressive” alterations that affect their ability to function appropriately in response to subsequent stimuli, such as exposure to invading pathogens [65], inflammatory disorders, surgery, trauma, or immune surveillance of neoplastic cells. In addition, it is possible that the effects on macrophages and monocytes may not only be mediated by the ingested RBCs per se , but also by the signal transduction pathways activated by the relevant cell surface receptor recognizing the “damaged” RBC (e.g., various Fc-gamma receptors for IgG-opsonized RBCs).…”

A comparison of different methods of red blood cell leukoreduction and additive solutions on the accumulation of neutrophil‐priming activity during storage

“…46 Injection of E. coli LPS induced fevers of more than 38 C, pulses or more than 90 beats/min, and mild tachypnea (>20 breaths/min) without evidence of pulmonary endothelial activation or PMN sequestration in the lung, a prerequisite for the two-event model of TRALI. 23,45,47,48 In contrast, animals used for the two-event model of TRALI demonstrated fevers with rigors, copious diarrhea, and when euthanized pulmonary sequestration of PMNs. 2,23,49 In addition, in tissue culture the activation of primary human, microvascular, endothelial cells does not occur until LPS concentrations of 20 ng/mL are reached and such systems do not allow for the removal, modification, or inactivation of LPS, which includes serum as part of the growth medium.…”

“…The two‐event model of TRALI has been recently criticized because of the inability of volunteers injected with 2 ng/kg Escherichia coli lipopolysaccharide (LPS) to manifest TRALI when transfused with autologous RBC units stored for 35 days . Injection of E. coli LPS induced fevers of more than 38°C, pulses or more than 90 beats/min, and mild tachypnea (>20 breaths/min) without evidence of pulmonary endothelial activation or PMN sequestration in the lung, a prerequisite for the two‐event model of TRALI . In contrast, animals used for the two‐event model of TRALI demonstrated fevers with rigors, copious diarrhea, and when euthanized pulmonary sequestration of PMNs .…”

Ferroportin inhibition attenuates plasma iron, oxidant stress, and renal injury following red blood cell transfusion in guinea pigs

“…Additionally, free iron is a labile toxicant that contributes to the generation of reactive oxygen species, lipid peroxides, and cellular injury . Nonetheless, other well‐conducted studies in humans have challenged these concepts in acute transfusion with endotoxemia . The contributions of transfusion‐based iron excess to organ injury and failure are well defined in diseases requiring chronic RBC replacement, such as sickle cell disease and the thalassemias .…”

“…6 Nonetheless, other well-conducted studies in humans have challenged these concepts in acute transfusion with endotoxemia. [10][11][12] ABBREVIATIONS: AKI = acute kidney injury; AUC = area under the curve; C max = maximum plasma concentration; Fe 2+ = ferrous iron; Fe 3+ = ferric iron; FPN = ferroportin; FPN-INH = ferroportin inhibitor; KDIGO = Kidney Disease: Improving Global Outcomes; NTBI = non-transferrin-bound iron.From the…”