T-cell suppression by red blood cells is dependent on intact cells and is a consequence of blood bank processing

Impact on cytokine accumulation in 35-day preserved whole blood due to resin adsorption

Blood transfusion in critically ill individuals such as sepsis was associated with higher morbidity and mortality. During storage, various bioactive substances accumulated, may exacerbate the initial immunosuppressive reaction in severely ill patients. The objective of this study is to explore how resin adsorption impacts the accumulation of cytokines and the presence of extracellular microvesicles (EVs) in whole blood. Through comparative analysis and screening, amberchrom CG 300 C was chosen to assess the adsorption efficiency and evaluate the quality of whole blood after adsorption. Subsequently, the supernatants from both the unadsorpted (UA) and adsorpted (A) groups were co-cultured with peripheral blood mononuclear cells (PBMCs) to assess their effects on cellular growth and cytokine concentrations. The findings of our study revealed that resin adsorption effectively eradicated most bioactive components in conserved blood, including IL-8, TGF-β, sCD40L, sFasL, without affecting the quality of the blood. Furthermore, scanning electron microscopy (SEM) revealed a reduction in extracellular microvesicles following adsorption. Compared to UA, A 's supernatant markedly enhanced PBMC growth (p < 0.01). Additionally, the A's supernatant markedly diminished the emission of pro-inflammatory cytokines, like IL-6. The research revealed that adsorbing resin effectively reduced bioactive substances from preserved whole blood, and did not impact red blood cell quality, proving to be a reliable method for extracting bioactive substances from storage blood. The results could pave the way for creating innovative blood bags and hold clinical significance in lowering the frequency of TRIM among patients who have undergone transfusions.

Rapid, label-free enrichment of lymphocytes in a closed system using a flow-through microfluidic device

The majority of adoptive cellular therapies are produced from peripheral mononuclear cells obtained via leukapheresis and further enriched for the cells of interest (e.g., T cells). Here, we present a first-of-its-kind closed system, which effectively removes ~85% of monocytes and ~88% of platelets, while recovering ~88% of concentrated T cells in a separate output stream, as the leukapheresis sample flows through a microfluidic device at 5 mL/min. The system is driven by a common peristaltic pump, enabled by a novel pressure wave dampener, and operates in a closed bag-to-bag configuration, without requiring any specialized, dedicated equipment. When compared to standard density gradient centrifugation on paired samples, the new system demonstrated a 1.5-fold increase in T cell recovery and a 2-fold reduction in inter-sample variability for this separation outcome. The T cell-to-monocyte ratio of the leukapheresis sample was increased to 20:1, whereas with density gradient processing it decreased to 2:1. As a result of superior purity and/or gentler processing, T cells enriched by the system showed a 2.7-times higher fold expansion during subsequent culture, and an overall 3.5-times higher cumulative yield. This centrifugation-free and label-free closed system for enriching lymphocytes could significantly simplify and standardize the manufacturing of life-saving cellular therapies.

Low-dose aspirin confers protection against acute cellular allograft rejection after primary liver transplantation

This study investigated the effect of low-dose aspirin in primary adult liver transplantation (LT) on acute cellular rejection (ACR) as well as arterial patency rates. The use of low-dose aspirin after LT is practiced by many transplant centers to minimize the risk of hepatic artery thrombosis (HAT), although solid recommendations do not exist. However, aspirin also possesses potent anti-inflammatory properties and might mitigate inflammatory processes after LT, such as rejection. Therefore, we hypothesized that the use of aspirin after LT has a protective effect against ACR. This is an international, multicenter cohort study of primary adult deceased donor LT. The study included 17 high-volume LT centers and covered the 3-year period from 2013 to 2015 to allow a minimum 5-year follow-up. In this cohort of 2365 patients, prophylactic antiplatelet therapy with low-dose aspirin was administered in 1436 recipients (61%). The 1-year rejection-free survival rate was 89% in the aspirin group versus 82% in the no-aspirin group (hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.63-0.94; p = 0.01). The 1-year primary arterial patency rates were 99% in the aspirin group and 96% in the no-aspirin group with an HR of 0.23 (95% CI, 0.13-0.40; p < 0.001). Low-dose aspirin was associated with a lower risk of ACR and HAT after LT, especially in the first vulnerable year after transplantation. Therefore, low-dose aspirin use after primary LT should be evaluated to protect the liver graft from ACR and to maintain arterial patency.

Red blood cell transfusions impact response rates to immunotherapy in patients with solid malignant tumors

Red blood cell (RBC) transfusions have been shown to exert immunosuppressive effects in different diseases. In consequence, RBC transfusions might also negatively influence the response to immunotherapeutic treatment approaches. To address how RBC transfusions impact response rates of antitumor immunotherapy (IT), we conducted a retrolective clinical study of patients with different solid tumors treated with IT (atezolizumab, pembrolizumab, nivolumab and/or ipilimumab). We assessed the number of RBC concentrates received within 30 days before and 60 days after the start of IT. Primary objective was the initial therapy response at first staging, secondary objectives the number of immune related adverse events and infections. 15 of 55 included patients (27.3%) received RBC concentrates. The response rates were 77.5% in the non-transfused (n=40) versus 46.7% in the transfused patient group (n=15) and reached statistical significance (p=0.047). The correlation between therapy response and transfusion was statistically significant (p=0.026) after adjustment for the only identified confounder “line of therapy”. In contrast, transfusion in the interval 30 days before IT showed no significant difference for treatment response (p=0.705). Moreover, no correlation was detected between RBC transfusion and irAE rate (p=0.149) or infection rate (p=0.135). In conclusion, we show for the first time that the administration of RBC transfusions during, but not before initiation of IT treatment, negatively influences the response rates to IT. Our findings suggest a restrictive transfusion management in patients undergoing IT to receive optimal response rates.

Development and Validation of a Machine Learning-Based Nomogram for Prediction of Ankylosing Spondylitis

Introduction

Ankylosing spondylitis (AS) is a chronic progressive inflammatory disease of the spine and its affiliated tissues. AS mainly affects the axial bone, sacroiliac joint, hip joint, spinal facet, and adjacent ligaments. We used machine learning (ML) methods to construct diagnostic models based on blood routine examination, liver function test, and kidney function test of patients with AS. This method will help clinicians enhance diagnostic efficiency and allow patients to receive systematic treatment as soon as possible.

Methods

We consecutively screened 348 patients with AS through complete blood routine examination, liver function test, and kidney function test at the First Affiliated Hospital of Guangxi Medical University according to the modified New York criteria (diagnostic criteria for AS). By using random sampling, the patients were randomly divided into training and validation cohorts. The training cohort included 258 patients with AS and 247 patients without AS, and the validation cohort included 90 patients with AS and 113 patients without AS. We used three ML methods (LASSO, random forest, and support vector machine recursive feature elimination) to screen feature variables and then took the intersection to obtain the prediction model. In addition, we used the prediction model on the validation cohort.

Results

Seven factors—erythrocyte sedimentation rate (ESR), red blood cell count (RBC), mean platelet volume (MPV), albumin (ALB), aspartate aminotransferase (AST), and creatinine (Cr)—were selected to construct a nomogram diagnostic model through ML. In the training cohort, the C value and area under the curve (AUC) value of this nomogram was 0.878 and 0.8779462, respectively. The C value and AUC value of the nomogram in the validation cohort was 0.823 and 0.8232055, respectively. Calibration curves in the training and validation cohorts showed satisfactory agreement between nomogram predictions and actual probabilities. The decision curve analysis showed that the nonadherence nomogram was clinically useful when intervention was decided at the nonadherence possibility threshold of 1%.

Conclusion

Our ML model can satisfactorily predict patients with AS. This nomogram can help orthopedic surgeons devise more personalized and rational clinical strategies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-022-00481-6.

AS is a chronic progressive inflammatory disease of the spine and its affiliated tissues. AS starts gradually, and its early symptoms are mild. Some hospitals lack HLA-B27 and related imaging instruments to assist in the diagnosis of AS. There are relatively few studies on liver function and kidney function of patients with AS. We used ML methods to construct diagnostic models. Our model can satisfactorily predict patients with AS. This diagnostic model can help orthopedic surgeons devise more personalized and rational clinical strategies.

Scalable Manufacturing of CAR T cells for Cancer Immunotherapy

As of April 2021, there are five commercially available chimeric antigen receptor (CAR) T cell therapies for hematological malignancies. With the current transition of CAR T cell manufacturing from academia to industry, there is a shift toward Good Manufacturing Practice (GMP)-compliant closed and automated systems to ensure reproducibility and to meet the increased demand for cancer patients. In this review we describe current CAR T cells clinical manufacturing models and discuss emerging technological advances that embrace scaling and production optimization. We summarize measures being used to shorten CAR T-cell manufacturing times and highlight regulatory challenges to scaling production for clinical use.

Statement of Significance ∣

As the demand for CAR T cell cancer therapy increases, several closed and automated production platforms are being deployed, and others are in development.This review provides a critical appraisal of these technologies that can be leveraged to scale and optimize the production of next generation CAR T cells.

Red blood cells exposed to cancer cells in culture have altered cytokine profiles and immune function

It is now accepted that red blood cells (RBCs) from healthy individuals regulate T-cell activity through modulating cytokine interactions, and that stored RBCs or RBCs from inflammatory cohorts are dysfunctional. Our study aimed to investigate how changes in RBCs that have been intentionally modified can affect T-cell activity as a mechanistic test of this modification. Exposure to a cancer cell line in culture was used to alter the cytokine profile of intact RBCs and the effect of these modified RBCs (ccRBCs) on T-cells was evaluated using flow cytometry. We used RBCs from healthy volunteers and quantified cytokines in RBC lysates and conditioned media using Luminex technology. During in vitro cancer cell exposure, RBCs sequestered a variety of cytokines including IL-8, bFGF, and VEGF. Although unmodified RBCs (oRBCs) stimulated proliferation of T-cells (Jurkat cells and peripheral blood mononucleated cells), ccRBCs augmented this proliferative response (3.5-fold and 1.9-fold more respectively). Unlike oRBCs, T-cells stimulated with ccRBCs were no longer protected from phytohemagglutinin-P-driven overexpression of GATA-3 and T-bet and these T-cells were induced to secrete a variety of cytokines including IL-17 and MCP-3. This study supports the hypothesis that RBCs are capable of binding and releasing cytokines in blood, and that modification of these cells can then also affect the T-cell response.

Impact of transfusion on survival in patients with myelodysplastic syndromes: Current knowledge, new insights and transfusion clinical practice

Red Blood Cell (RBC) transfusion dependence is a prevalent consequence of anaemia in patients with lower risk Myelodysplastic Syndromes (MDS). These patients have shorter survival compared to patients responding to Erythropoiesis-stimulating agents (ESA), raising the question of potential negative effects of chronic RBC transfusions on MDS prognosis, independently of IPSS-R. Besides commonly identified complications of transfusions like iron toxicity or cardiac events, oxidative stress could be a risk factor for ineffective haematopoiesis. Recently, physicochemical changes of RBC during storage have been described. These changes called storage lesions could play a role in immunomodulation in vivo. We review the currently identified sources of potential impact on transfusion-associated effects in MDS patients and we discuss the unexplored potential role of erythrocyte-derived-extracellular vesicles. They could amplify impairment of haematopoiesis in addition to the negative intrinsic effects underlying the pathology in MDS. Thus, chronic RBC transfusions appear to potentially impact the outcome of MDS.

The emerging role of red blood cells in cytokine signalling and modulating immune cells

For many years red blood cells have been described as inert bystanders rather than participants in intercellular signalling, immune function, and inflammatory processes. However, studies are now reporting that red blood cells from healthy individuals regulate immune cell activity and maturation, and red blood cells from disease cohorts are dysfunctional. These cells have now been shown to bind more than 50 cytokines and have been described as a sink for these molecules, and the loss of this activity has been correlated with disease progression. In this review, we summarise what is currently understood about the role of red blood cells in cytokine signalling and in modulating the activity of immune cells. We also discuss the implications of these findings for transfusion medicine and in furthering our understanding of anaemia of chronic inflammation. By bringing these disparate units of work together, we aim to shine a light on an area that requires significantly more investigation.

Transfusion of red blood cells does not impact progression-free and overall survival after surgery for ovarian cancer

BACKGROUND

Allogeneic red blood cells (RBCs) have the potential to impact the immunosurveillance of the recipient and may therefore increase the risk of recurrence after cancer surgery. In this article the relationship between perioperative RBC transfusion and the risk of recurrence after ovarian cancer surgery is examined.

STUDY DESIGN AND METHODS

This is a retrospective cohort analysis of a prospective database of patients who underwent surgery due to primary ovarian cancer between 2006 and 2014 and who had no residual disease after surgery. Patients who did and did not receive perioperative RBC transfusion were compared. The primary endpoint was progression-free survival (PFS). Propensity score matching (PSM) and Cox proportional hazards regression (CPH) was used to control for between-group differences of prognostic determinants.

RESULTS

A total of 529 patients with a median follow-up of 51.4 months (95% CI, 46.1-56.5) were eligible for analysis. Of those, 408 patients (77.1%) received allogeneic, leukoreduced RBCs with a median of 4 units (IQR, 2-6) per patient. There was a strong selection bias of prognostic determinants between patients with and without transfusion. In unadjusted analysis, transfusion of RBCs was associated with an increased risk of cancer recurrence (hazard ratio [HR] of PFS 2.71 [95% CI, 1.94-3.77], p < 0.001). After bias reduction, transfusion of RBCs was no longer associated with an increased risk of cancer recurrence, neither in PSM-adjusted (HR 1.03 [95% CI, 0.59-1.80], p = 0.91), nor in multivariable CPH-adjusted analysis (HR 1.26 [95% CI, 0.85-1.86], p = 0.23).

CONCLUSION

Perioperative transfusion of RBCs did not increase the risk of recurrence after ovarian cancer surgery.

The Challenge of Variability in Chimeric Antigen Receptor T cell Manufacturing

Autologous Chimeric Antigen Receptor (CAR) T cell manufacturing involves the modification and expansion of T cells obtained by apheresis collection from a patient. The mechanism of apheresis collection and the specific clinical features seen in these patients combine to generate apheresis products with high variability of content. Manufacturers often attempt to minimize this variability such that processes can be standardize in accordance with Good Manufacturing Practices (GMP). Such standardization improves efficiency and helps to ensure robustness of the overall process. Apheresis product variability can negatively impact T cell manufacturing success. Patient and collection driven variability often leads to non-T cells entering the apheresis product. Many of these cells can directly or indirectly impair T cell activation and expansion, decreasing the manufacturing success rate. Therefore, patient driven variability observed in apheresis products, must be mitigated through downstream processing. T cell enrichment is one step in the manufacturing cycle that can reduce process variability by generating more uniform downstream material. However, current T cell enrichment methods have limitations. Much of this type of variability can be avoided by collecting patients earlier in their disease or treatment course, this is not current, widespread or standard practice. While variability poses challenges to successful CAR T cell manufacturing and mitigation strategies can be successful, more work is needed in this area.

Vaccine immune response, autoimmunity and morbidity after neonatal blood exchange transfusion

INTRODUCTION

A blood exchange transfusion (BET) is most commonly performed to treat severe neonatal haemolytic disease. A distinct form of blood transfusion adverse reaction is transfusion-related immunomodulation. The purpose of our retrospective single-centre case-control cohort study was to investigate whether a blood exchange transfusion in the neonatal period provokes immunomodulation and affects humoral immune response to vaccination, morbidity and occurrence of autoantibodies.

METHODS

Study subjects were 74 apparently healthy children, who were born at term as appropriate for gestational age and received four doses of diphtheria and tetanus toxoid vaccine. Forty-one received BET due to neonatal hemolytic disease and no other blood product afterwards, while 33 did not receive any blood products. Analysis of diphtheria, tetanus and autoimmune antibodies was performed and their medical records were analyzed for infectious, allergic, cancerous and autoimmune diseases.

RESULTS

A clearly exaggerated immune response to diphtheria (1.016 IU/mL, 95% confidence interval (CI) 0.662-1.369 IU/mL vs. 0.515 IU/mL, 95% CI 0.363 to 0.626 IU/mL, P = 0.011) and slightly exaggerated immune response to tetanus vaccine (1.798 IU/mL, 95% CI 1.180-2.416 IU/mL vs. 1.036 IU/mL, 95% CI 0.398-1.673 IU/mL, P = non-specific) were observed in BET subjects. A propensity towards autoimmunity (25.8% vs. 12.5%, P = non-specific) was observed in BET subjects. However, BET in the neonatal period did not influence the occurrence of bacterial, childhood viral diseases with exception of varicella (43.9% vs. 21.2%, P = 0.040), autoimmune and cancer diseases.

CONCLUSION

BET impacted humoral immune response to diphtheria and tetanus vaccine and occurrence of autoimmune antibodies, but did not affect morbidity and the occurrence of autoimmune diseases. These effects could be related to massive antigenic load of BET and an accelerated priming of immune cells and consequent immunomodulation.

Red blood cell storage lesion: causes and potential clinical consequences

Red blood cells (RBCs) are a specialised organ that enabled the evolution of multicellular organisms by supplying a sufficient quantity of oxygen to cells that cannot obtain oxygen directly from ambient air via diffusion, thereby fueling oxidative phosphorylation for highly efficient energy production. RBCs have evolved to optimally serve this purpose by packing high concentrations of haemoglobin in their cytosol and shedding nuclei and other organelles. During their circulatory lifetimes in humans of approximately 120 days, RBCs are poised to transport oxygen by metabolic/redox enzymes until they accumulate damage and are promptly removed by the reticuloendothelial system. These elaborate evolutionary adaptions, however, are no longer effective when RBCs are removed from the circulation and stored hypothermically in blood banks, where they develop storage-induced damages ("storage lesions") that accumulate over the shelf life of stored RBCs. This review attempts to provide a comprehensive view of the literature on the subject of RBC storage lesions and their purported clinical consequences by incorporating the recent exponential growth in available data obtained from "omics" technologies in addition to that published in more traditional literature. To summarise this vast amount of information, the subject is organised in figures with four panels: i) root causes; ii) RBC storage lesions; iii) physiological effects; and iv) reported outcomes. The driving forces for the development of the storage lesions can be roughly classified into two root causes: i) metabolite accumulation/depletion, the target of various interventions (additive solutions) developed since the inception of blood banking; and ii) oxidative damages, which have been reported for decades but not addressed systemically until recently. Downstream physiological consequences of these storage lesions, derived mainly by in vitro studies, are described, and further potential links to clinical consequences are discussed. Interventions to postpone the onset and mitigate the extent of the storage lesion development are briefly reviewed. In addition, we briefly discuss the results from recent randomised controlled trials on the age of stored blood and clinical outcomes of transfusion.

Effect of storage period of red blood cell suspensions on helper T-cell subpopulations

BACKGROUND

The aim of this study was to investigate the immunological alterations that occur during the storage of erythrocyte suspensions which may lead to transfusion-related immunomodulation following allogeneic blood transfusion.

MATERIALS AND METHODS

One part of the erythrocyte suspensions obtained from donors was leucoreduced while the other part was not. The leucoreduced (LR) and non-leucoreduced (NL) erythrocyte suspensions were then further divided into three equal amounts which were stored for 0, 21 or 42 days prior to measurements, by enzyme-linked immunosorbent assays, of cytokine levels in their supernatants. T-helper (Th) lymphocyte subgroups and gene expression were analysed in the NL erythrocyte suspensions by flow cytometry and real-time polymerase chain reaction, respectively. Results were compared to those of storage day 0.

RESULTS

By day 21, the number of Th2 cells had increased significantly and the numbers of Th1, Th22 and Treg cells had decreased significantly in the NL erythrocyte suspensions. On day 42 the numbers of Th2 and Treg cells in the NL suspensions were significantly increased while the number of Th1 cells was significantly decreased. The levels of transcription factors (TBX21, GATA3, and SPI.1) were significantly decreased on days 21 and 42, and AHR, FOXP3 and RORC2 levels were significantly increased on day 42 in NL erythrocyte suspensions. The decrease in interleukin-22 and increase in transforming growth factor-β levels found in NL erythrocyte suspensions on day 21 were statistically significant. Elevated levels of interleukin-17A were found in both LR and NL erythrocyte suspensions on day 42.

DISCUSSION

Our results suggest that allogeneic leucocytes and cytokines may play significant roles in the development of transfusion-related immunomodulation.

Perioperative Allogeneic Red Blood-Cell Transfusion Associated with Surgical Site Infection After Total Hip and Knee Arthroplasty

BACKGROUND

Perioperative allogeneic red blood-cell transfusion is a suspected risk factor for surgical site infection (SSI) after total joint arthroplasty (TJA), but the interrelationships among SSI risk, transfusion dose, preoperative anemia, and the presence of coagulopathies have not been well described.

METHODS

Data on SSI within 1 year after surgery as well as on transfusion with blood products within 30 days after surgery were obtained for 6,788 patients who had undergone primary or revision total hip or knee arthroplasty from 2000 to 2011 in a single hospital system. Multivariate logistic regression modeling was used to determine the independent association between allogeneic red blood-cell transfusion and SSI.

RESULTS

There was a dose-dependent association between allogeneic red blood-cell transfusion and SSI, with the infection rate increasing as the transfusion dose increased from 1 unit (odds ratio [OR] = 1.97; 95% confidence interval [CI] = 1.38, 2.79; p < 0.001), to 2 units (OR = 2.20; CI = 1.37, 3.44; p = 0.002), to 3 units (OR = 3.66; CI = 1.72, 7.16; p = 0.001), and to >3 units (OR = 7.40; CI = 4.91, 11.03; p < 0.001) after controlling for medical comorbidities, planned procedure, preoperative anemia, and preexisting coagulopathies. A preexisting bleeding disorder (OR = 2.09; CI = 1.57, 2.80; p < 0.001) and clotting disorder (OR = 1.37; CI = 1.14, 1.64; p = 0.001) and preoperative anemia (OR = 3.90; CI = 3.31, 4.61; p < 0.001) were all independent risk factors for transfusion after adjusting for the planned procedure.

CONCLUSIONS

We found a dose-dependent relationship between allogeneic red blood-cell transfusion and SSI risk after total hip or knee arthroplasty. Additionally, preoperative anemia or a known bleeding or clotting disorder were risk factors for the need for allogeneic red blood-cell transfusion. Our findings underscore the need for preoperative risk assessment, methods to limit surgical tissue injury, and optimized blood conservation strategies.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Mechanisms of red blood cell transfusion-related immunomodulation

Red blood cell (RBC) transfusion is common in critically ill, postsurgical, and posttrauma patients in whom both systemic inflammation and immune suppression are associated with adverse outcomes. RBC products contain a multitude of immunomodulatory mediators that interact with and alter immune cell function. These interactions can lead to both proinflammatory and immunosuppressive effects. Defining clinical outcomes related to immunomodulatory effects of RBCs in transfused patients remains a challenge, likely due to complex interactions between individual blood product characteristics and patient-specific risk factors. Unpacking these complexities requires an in-depth understanding of the mechanisms of immunomodulatory effects of RBC products. In this review, we outline and classify potential mediators of RBC transfusion-related immunomodulation and provide suggestions for future research directions.

Medical comorbidities and perioperative allogeneic red blood cell transfusion are risk factors for surgical site infection after shoulder arthroplasty

BACKGROUND

Multiple perioperative factors have been implicated in infection risk after shoulder arthroplasty. The purpose of this study was to determine surgical site infection (SSI) risk due to medical comorbidities or blood transfusion after primary or revision shoulder arthroplasty.

METHODS

Comprehensive data on medical comorbidities, surgical indication, perioperative transfusion, and SSI were obtained for 707 patients who underwent primary or revision hemiarthroplasty or total shoulder arthroplasty in a single hospital system. Multivariate Poisson regression was used to determine the independent association between allogeneic red blood cell transfusion, medical comorbidities, and SSI after controlling for procedure.

RESULTS

The SSI rate was 1.9% for primary hemiarthroplasties and 1.3% for primary total shoulder arthroplasties. Among patients without prior shoulder infection, revision arthroplasty or prior open reduction and internal fixation had higher SSI risk than primary arthroplasties (incidence risk ratio [IRR], 11.4; 95% confidence interval [CI], 3.84-34.0; P < .001); among primary arthroplasties, SSI risk factors included male gender (IRR, 60.0; CI, 4.39-819; P = .002), rheumatoid arthritis (IRR, 8.63; CI, 1.84-40.4; P = .006), and long-term corticosteroid use (IRR, 37.4; CI, 5.79-242; P < .001). Perioperative allogeneic red blood cell transfusion significantly increased SSI risk and was dose dependent (IRR, 1.68 per unit packed red blood cell; CI, 1.21-2.35; P = .002).

CONCLUSION

Gender, rheumatoid arthritis, and long-term (>1 year) corticosteroid use affect SSI risk after shoulder arthroplasty. Revision surgery, particularly in the setting of prior infection, increased risk of future infection. Finally, allogeneic red blood cell transfusion increases SSI risk after shoulder arthroplasty in a dose-dependent manner.

Leukocyte and plasma activation profiles in chronically transfused patients with a history of allergic reactions

BACKGROUND

Allergic transfusion reactions are drawbacks to the benefits of transfusion. Classically, allergic transfusion reactions depend on histamine release from mast cells or basophils, but other leukocyte subsets may also be important. Thus, we propose to better define the exact leukocyte subsets involved in allergic transfusion reactions.

STUDY DESIGN AND METHODS

The overall objective of the current study was to compare the activation of specific peripheral blood leukocyte subsets (monocytes, neutrophils, eosinophils, and basophils) in a cohort of 13 patients who received chronic transfusions and had a history of allergic transfusion reactions compared with a control group of patients who received chronic transfusions and had no history of allergic transfusion reactions. Leukocyte subsets were analyzed by flow cytometry at baseline and after red blood cell transfusion, and cytokine levels in platelet-free plasma collected at the same time points were measured by Luminex assay.

RESULTS

Flow cytometry and cytokine profiles before and after transfusion did not differ significantly between patients who did and did not have a history of allergic transfusion reactions (p > 0.05). However, post-transfusion samples from both groups showed a decrease in CD63 expression in basophils, monocytes, and eosinophils and a decrease in CD45 expression in all leukocyte subsets compared with pretransfusion samples. Interleukin 10 levels increased after transfusion in the group with a history of allergic transfusion reactions (p = 0.0469), and RANTES (regulated upon activation, normal T-cell expressed and secreted) was significantly decreased post-transfusion in all patients (p = 0.0122).

CONCLUSION

None of the leukocyte subsets from patients who had a history of allergic transfusion reactions significantly increased in activation either before or after transfusion. All leukocyte subsets from patients who did and did not have a history of allergic transfusion reactions decreased in their activation profile upon transfusion challenge.

Red blood cell transfusion in surgical cancer patients: Targets, risks, mechanistic understanding and further therapeutic opportunities

Anemia is present in more than half of cancer patients and appears to be an independent prognostic factor of short- and long-term adverse outcomes. It increases in the advanced period of cancer and perioperatively, in patients with solid tumors who undergo surgery. As a result, allogeneic red blood cell (RBC) transfusion is an indispensable treatment in cancer. However, its safety remains controversial, based on several laboratory and clinical data reporting a linkage with increased risk for cancer recurrence, infection and cancer-related mortality. Immunological, inflammatory and thrombotic reactions mediated by the residual leukocytes and platelets, the stored RBCs per se, the biological response modifiers and the plasticizer of the unit may underlie infection and tumor-promoting effects. Although the causality between transfusion and infection has been established, the effects of transfusion on cancer recurrence remain confusing; this is mainly due to the extreme biological heterogeneity that characterizes RBC donations and cancer context. In fact, the functional interplay between donation-associated factors and recipient characteristics, including tumor biology per se, inflammation, infection, coagulation and immune activation state and competence may synergistically and individually define the clinical impact of each transfusion in any given cancer patient. Our understanding of how the potential risk is mediated is important to make RBC transfusion safer and to pave the way for novel, promising and highly personalized strategies for the treatment of anemia in surgical cancer patients.

Transfusion-related immunomodulation: review of the literature and implications for pediatric critical illness

Transfusion-related immunomodulation (TRIM) in the intensive care unit (ICU) is difficult to define and likely represents a complicated set of physiologic responses to transfusion, including both proinflammatory and immunosuppressive effects. Similarly, the immunologic response to critical illness in both adults and children is highly complex and is characterized by both acute inflammation and acquired immune suppression. How transfusion may contribute to or perpetuate these phenotypes in the ICU is poorly understood, despite the fact that transfusion is common in critically ill patients. Both hyperinflammation and severe immune suppression are associated with poor outcomes from critical illness, underscoring the need to understand potential immunologic consequences of blood product transfusion. In this review we outline the dynamic immunologic response to critical illness, provide clinical evidence in support of immunomodulatory effects of blood product transfusion, review preclinical and translational studies to date of TRIM, and provide insight into future research directions.