Leukocyte Depletion Research Articles

Leukocyte-Poor Platelet-Rich Plasma for the Management of Knee Osteoarthritis: A Retrospective Study With 12 Months of Follow-Up.

Introduction The knee, the most frequently affected joint in osteoarthritis (OA), impacts the life quality of millions of individuals globally, resulting in a considerable healthcare burden. Conservative treatments are preferred, turning to surgical intervention when necessary. Nonetheless, these conventional modalities have drawbacks. Recently, the use of regenerative medicine therapies, including autologous peripheral blood-derived orthobiologics (APBOs), such as leukocyte-poor platelet-rich plasma (LP-PRP), has evolved and demonstrated the ability to manage knee OA. The primary objective of this investigation was to evaluate the efficacy of LP-PRP via widely used patient-reported outcome measures (PROMs) in grade I or II (on the Kellgren-Lawrence scale) knee OA patients. The secondary objective was to characterize the formulated LP-PRP and determine the efficiency of the leukodepletion filter used for leukocyte removal and platelet recovery. Methods This investigation was a retrospective analysis of data collected from patients treated at a single center over a period of 15 months.Data from 40 patients included in this study were intra-articularly injected with 3mL of formulated LP-PRPunder ultrasound guidance. PROMs questionnaires, including Kujala and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores, were used and responses were documented at baseline and up to 12 months follow-up. The characterization of the formulated LP-PRP and the efficiency of the leukodepletion filter in removing leukocytes and recovering platelets were assessed via complete blood count (CBC) analysis. Results The intra-articular administration of LP-PRP resulted in statistically significant improvements in Kujala and WOMAC scores in patients with Grade I or II OA of the knee at all follow-up time points (four to 12 months) compared to the respective baseline scores. The subgroup analysis showed significant improvements in Kujala and WOMAC scores inboth male and female grade I or II knee OA patients with or without comorbidities, including diabetes and/or hypertension. The characterization of formulated PRP showedplatelet concentration to be at least 6x compared to the baseline whole blood levels, the absolute platelet count to be at least 5 billion, and total leukocytes, lymphocytes, neutrophils, and RBCs were depleted by over 88%, 82%, 98%, and 98%, respectively. In addition, the utilization of the PuriBlood leukocyte reduction filter (Puriblood Medical Co. Ltd., Baoshan Township, Taiwan) led to the depletion of approximately 93% of leukocytes and the recovery of about 83% of platelets. Conclusions Administration of LP-PRP resulted in significant improvements in pain and function of patients suffering from grade I or II OA of the knee. In addition, the leukodepletion filter used to formulate LP-PRP, successfully resulted in the depletion of leukocytes while recovering the platelets. More sufficiently powered, multi-center, prospective, non-randomized, and randomized controlled trials with long-term follow-up are needed to further establish the effectiveness of this formulation in knee OA patients.

Evaluation of leukocyte depletion of packed red blood cells for the prevention of clinically observed transfusion reactions at a medical center in Eastern Taiwan

ABSTRACT Objectives: The incidence of febrile nonhemolytic transfusion reactions (FNHTRs) is correlated with the level of cytokines released by donor leukocytes in blood bags during storage, which is the most common transfusion reaction. The study aimed to reveal whether the use of leukocyte-poor red blood cells (LPRBCs) can reduce the incidence of transfusion reactions to promote patient safety. Materials and Methods: From January 2014 to June 2022, 158,122 blood transfusion reports were collected from a medical center in Eastern Taiwan. Data were categorized into three groups according to usage prepromotion use of LPRBCs (January 2014–April 2016), promotion use of LPRBCs (May 2016 to February 2018), and full utilization of LPRBCs (March 2018 to June 2022). According to the American Association of Blood Bank Common Transfusion Reaction Reporting Form version 2.0 reporting system, FNHTRs were classified as moderate transfusion reactions. We used these data to analyze the association between LPRBC use and transfusion reaction rate. Results: At our hospital, the LPRBC usage rate from January 2014 to April 2016, May 2016 to February 2018, and March 2018 to June 2022 was 5.37%, 34.82%, and 56.45%, respectively. The total transfusion reaction rate from January 2014 to April 2016 was 1.66%, whereas the moderate reaction rate was 1.29%. The total transfusion and moderate reaction rates from May 2016 to February 2018 were 1.41% and 1.00%, whereas those from March 2018 to June 2022 were 0.95% and 0.63%, respectively. The total transfusion and moderate reaction rates from March 2018 to June 2022 decreased by 42.8% and 51.2%, respectively, compared with those from January 2014 to April 2016. We further compared the incidence of transfusion reactions caused by packed red blood cells (PRBC) and LPRBC products in different years. The results showed that between 2014 and 2022, the types of blood transfusion reaction caused using PRBC and LPRBC products are the mild transfusion reaction rate of 0.20%/0.20%, the moderate transfusion reaction rate of 1.61%/0.69%, the severe transfusion reaction rates 0.38%/0.16%, and the total transfusion reaction rates 2.19%/1.05%. Conclusion: Our study results indicate that both total transfusion and moderate reaction rates significantly decreased with increasing LPRBC usage rate. Based on our data analysis, LPRBC is more effective in reducing moderate and severe transfusion reactions than PRBC.

Risk Factors for Sepsis in Postoperative Patients

Sepsis is a severe acute infection that can lead to organ failure and mortality in 30-50% of patients. It ranks among the top 10 causes of mortality in the United States and has increased significantly since the 1970s. Postoperative sepsis, the primary type of sepsis, accounts for almost one-third of all sepsis cases. Postoperative sepsis is a major cause of illness and death for hospitalized patients, often leading to multiple organ failure and mortality. A study found that patients aged 18 years or older who have undergone surgical interventions and have been hospitalized for at least 4 days after the operation have a higher likelihood of developing sepsis. The most prevalent complication after radical gastrectomy for stomach cancer is postoperative infection, which occurs through leukocyte depletion in transfusion patient. Being male or over 65 significantly increased the likelihood of having postoperative sepsis. Sex hormones significantly influence the body's response to sepsis, and elderly individuals may be more susceptible due to deterioration of immune system function and age-related immunosenescence. Chronic renal illness, diabetes, and chronic heart failure have the highest risks of developing postoperative sepsis, ranked first, second, and third, respectively. Dysfunctions in the cardiovascular and hematological systems also have the highest probability of leading to the development of postoperative sepsis. These findings suggest potential areas for future research to decrease the impact of the disease.

Rosamultin ameliorates radiation injury via promoting DNA injury repair and suppressing oxidative stress in vitro and in vivo

Radiotherapy remains the preferred treatment option for cancer patients with the advantages of broad indications and significant therapeutic effects. However, ionizing radiation can also damage normal tissues. Unfortunately, there are few anti-radiation damage drugs available on the market for radiotherapy patients. Our previous study showed that rosamultin had antioxidant and hepatoprotective activities. However, its anti-radiation activity has not been evaluated. Irradiating small intestinal epithelial cells and mice with whole-body X-rays radiation were used to evaluate the in vitro and in vivo effects of rosamultin, respectively. Intragastric administration of rosamultin improved survival, limited leukocyte depletion, and reduced damage to the spleen and small intestine in irradiated mice. Rosamultin reversed the downregulation of the apoptotic protein BCL-2 and the upregulation of BAX in irradiated mouse small intestine tissue and in irradiation-induced small intestinal epithelial cells. DNA-PKcs antagonists reversed the promoting DNA repair effects of rosamulin. Detailed mechanistic studies revealed that rosamultin promoted Translin-associated protein X (TRAX) into the nucleus. Knockdown of TRAX reduced the protective effect of rosamultin against DNA damage. In addition, rosamultin reduced irradiation-induced oxidative stress through promoting Nrf2/HO-1 signaling pathway. To sum up, in vitro and in vivo experiments using genetic knockdown and pharmacological activation demonstrated that rosamultin exerts radioprotection via the TRAX/NHEJ and Nrf2/HO pathways.

P727 Clinical efficacy of apheresis in Ulcerative Colitis. The experience of four tertiary centers

Abstract Background Selective depletion of myeloid lineage leucocytes by adsorptive granulocyte and monocyte apheresis (GMA) with Adacolumn ® was introduced as a nonpharmacologic treatment for ulcerative colitis (UC) in 2000. It has been reported that GMA may be effective in combination with immunosuppressive treatment in a subset of patients. Τhe purpose of our study is the evaluation of the effectiveness and safety of GMA as a complementary treatment in patients with refractory ulcerative colitis. Methods Prospective data collection of a patient cohort with refractory UC receiving Adacolumn ® as an adjunct to their medical treatment. The therapeutic protocol has 2 phases: The induction phase entails two sessions per week for at least 3 weeks. The maintenance includes one weekly session for one month, one session every 15 days for one the next month, and monthly sessions thereafter. The patients’ medical treatment was maintained during the sessions. As a failure to GMA was considered the need for colectomy, the switch to a different treatment and inability to discontinue steroids. Response was evaluated after completion of at least 6 sessions of GMA. Results Ten patients with refractory UC were offered Adacolumn® between February 2021 and September 2023. Mean age was 39.6 years (22-61years). All patients had failed at least one biologic treatment and two-thirds two biologics. Their treatment which was maintained during GMA was: tofacitinib 10mg bid for 4 patients, ustekinumab 90mg sc every 8 weeks for 3, vedolizumab 300 mg every 8 weeks for 2, and corticosteroids 16mg for one. The median duration of treatment was 5.1 months (2-13 months), while the median number of sessions was 16 (6-45). Clinical and endoscopic remission was achieved in two cases (20%), after 13 sessions for both (in brackets in the Table) whereas two patients (20%) responded clinically according to partial Mayo score. Treatment failure was documented for 6 patients (60%) after 6-45 sessions. Patient number 4 performed 45 sessions in different hospitals because he was reluctant to be operated. Three underwent colectomy and three discontinued due to non-response. No adverse effects were observed. The initial median of partial Mayo score was 6 (5-9) while at the end of the evaluation was 4.5 (0-9). Table 1 summarizes the results of our study. Conclusion 1) GMA may be beneficial as an adjunct to biologics in refractory to medical treatment UC patients. 2) Interestingly, all patients on tofacitinib showed a favorable response after the addition of GMA. This observation may help define a subset of UC patients who may benefit the most.

A novel selective leukocyte depletion human whole blood model reveals the specific roles of monocytes and granulocytes in the cytokine response to Escherichia coli.

The lepirudin-based human whole blood model is a well-established ex vivo system to characterize inflammatory responses. However, the contribution of individual cell populations to cytokine release has not been investigated. Thus, we modified the model by selectively removing leukocyte subpopulations to elucidate their contribution to the inflammatory response. Lepirudin-anticoagulated whole blood was depleted from monocytes or granulocytes using StraightFrom Whole Blood MicroBeads. Reconstituted blood was incubated with Escherichia coli (108/mL) for 2 hours at 37 °C. CD11b, CD62P, and CD63 were detected by flow cytometry. Complement (C3bc, sC5b-9) and platelet activation (platelet factor 4, NAP-2) were measured by enzyme-linked immunosorbent assay. Cytokines were quantified by multiplex assay. A significant (P < 0.05) specific depletion of the monocyte (mean = 86%; 95% confidence interval = 71%-92%) and granulocyte (mean = 97%; 95% confidence interval = 96%-98%) population was obtained. Background activation induced by the depletion protocol was negligible for complement (C3bc and sC5b-9), leukocytes (CD11b), and platelets (NAP-2). Upon Escherichia coli incubation, release of 10 of the 24 cytokines was solely dependent on monocytes (interleukin [IL]-1β, IL-2, IL-4, IL-5, IL-17A, interferon-γ, granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, macrophage inflammatory protein-1α, and fibroblast growth factor-basic), whereas 8 were dependent on both monocytes and granulocytes (IL-1ra, IL-6, IL-8, IL-9, IL-10, macrophage inflammatory protein-1β, tumor necrosis factor, and eotaxin). Six cytokines were not monocyte or granulocyte dependent, of which platelet-derived growth factor and RANTES were mainly platelet dependent. We document an effective model for selective depletion of leukocyte subpopulations from whole blood, without causing background activation, allowing in-depth cellular characterization. The results are in accordance with monocytes playing a major role in cytokine release and expand our knowledge of the significant role of granulocytes in the response to E. coli.

Evaluation of the Feasibility of Transfusing Leukocyte Depletion Filter–Processed Intraoperative Cell Salvage Blood in Metastatic Spine Tumor Surgery: Protocol for a Non Randomized Study (Preprint)

Evaluation of the Feasibility of Transfusing Leukocyte Depletion Filter–Processed Intraoperative Cell Salvage Blood in Metastatic Spine Tumor Surgery: Protocol for a Non Randomized Study (Preprint)

Low-cost 3D printed inertial flow microfluidic devices for cellular isolation in liquid biopsies

Microfluidic devices for biomedical applications manufactured by conventional lithography often lack flexibility in design integration. Limitations in aspect ratio or in the ability to integrate microfluidic elements located in different planes reduce the available design options. Regarding this, 3D printing offers several advantages over traditional fabrication techniques. However, 3D printing technologies indeed show some limitations in the resolution of the microstructures obtained in comparison with standard lithography. We have optimized a low-cost multi-system combining standard lithography and 3D printing to design inertial flow microfluidic devices with different channels dimensions for cell concentration or isolation in blood, which are adaptable to cancer tumor cell (CTC) detection in liquid biopsies. CTC separation from complete blood using microfluidic devices often faces the challenge of leukocyte contamination due to their similar size with CTC. However, with 3D printing, we can create larger channels than those produced through lithography, enabling the use of beads coated with antibodies that bind to leukocytes expressing the CD45+ receptor. This binding results in larger particles that could be separated from the CTCs in the microfluidic devices, providing a more purified CTC sample. Microfluidic spiral structures were obtained with standard lithography for a first purification step using rectangular channel of 152 µm height and 500 µm width channels. The blood samples after processingE were analyzed by flow cytometry and revealed a recovery efficiency using two different CTC models of 80% ± 4% and 95% ± 4%. Also, the system enables 97.5% ± 1.89% and 83.4% ± 3.6% depletion of erythrocytes and leukocytes respectively. In addition, single or double microfluidic spiral structures to reduce leukocyte contamination using beads were directly fabricated using stereolithography 3D printing. In the single device with a channel of 600 μm and 1.4 mm of height and width respectively, and in the case of the device with two spirals placed on different planes, with a channel of 800 μm and 1.4 mm of height and width respectively. In addition, a read-out system based on an electronic circuit with piezoelectric micropumps, and a low-cost optical microscope was designed and adapted. This configuration avoids usual limitations when using syringe pumps and big microscopes, such as lack of sample recirculation, loss of CTCs during stabilization, blood sedimentation in the syringe, and reduced portability. Finally, combining a microfluidic spiral to separate red blood cells and partially leucocytes with the 3D microfluidic spiral to separate particles as the beads coated with CD45+ antibodies, could be possible to achieve a total leukocyte depletion up to 91%, and a maximum recovery of cancer cells up to 95%.

Therapeutic Leukocytapheresis to relieve priapism due to leukostasis in CML patients: Our experience in a tertiary care centre

Hyperleukocytosis in leukemic patients may cause tumour lysis syndrome, disseminated intravascular coagulopathy, and leukostasis, resulting in decreased tissue perfusion and increasing the risk of mortality. Since the myeloid blasts are larger than lymphoid blasts and are less deformable, complications of leukostasis are seen more frequently in myeloid leukemia. Priapism is a less common complication associated with leukostasis in leukaemia patients that should be treated as soon as possible to avoid ischemic injuries. Although chemotherapeutic drugs such as hydroxyurea and imatinib are used to treat hyperleukocytosis in CML patients, leukocytapheresis (LCP) can achieve rapid cytoreduction. Prophylactic LCP could not offer any advantage over aggressive chemotherapy, but therapeutic leukocyte depletion has a proven role in patients having symptomatic leukostasis due to high tumour burden. Three patients with ischaemic priapism were reported at our institute's emergency department, where detumescence could not be achieved by distal shunting or aspiration with phenylephrine instillation. The procedure of therapeutic LCP was performed in all three patients on an emergency basis, which resolved painful priapism by rapid cytoreduction.

Statistical Assessment of Drug Synergy from In Vivo Combination Studies using Mouse Tumor Models.

Drug combination therapy is a promising strategy for treating cancer, however, its efficacy and synergy require rigorous evaluation in preclinical studies before going to clinical trials. Existing methods have limited power to detect synergy in animal studies. Here, we introduce a novel approach to assess in vivo drug synergy with high sensitivity and low false discovery rate. It can accurately estimate combination index and synergy score under the Bliss independence model and the highest single agent (HSA) model without any assumption on tumor growth kinetics, study duration, data completeness and balance for tumor volume measurement. We show that our method can effectively validate in vitro drug synergy discovered from cell line assays in in vivo xenograft experiments, and can help to elucidate the mechanism of action for immune checkpoint inhibitors in syngeneic mouse models by combining an anti-PD-1 antibody and several tumor-infiltrating leukocytes depletion treatments. We provide a unified view of in vitro and in vivo synergy by presenting a parallelism between the fixed-dose in vitro and the 4-group in vivo combination studies, so they can be better designed, analyzed and compared. We emphasize that combination index, when defined here via relative survival of tumor cells, is both dose and time dependent, and give guidelines on designing informative in vivo combination studies. We explain how to interpret and apply Bliss and HSA synergies. Finally, we provide an open-source software package named invivoSyn that enables automated analysis of in vivo synergy using our method and several other existing methods.

Evaluation of leukocyte depletion of packed red blood cell units and impact on clinically observed transfusion reactions.

The aim of this retrospective study was to determine whether there is an association between leukoreduction of packed red blood cell (pRBC) units and reduction of clinically observed transfusion reactions (TR), particularly febrile non-haemolytic transfusion reactions (FNHTR), and better outcomes in dogs. Secondary aims were to evaluate the effects of other factors suspected to influence transfusion reaction frequency or survival, including crossmatching, use of immunosuppressive drugs, and age and number of the blood products being administered. Medical data on dogs transfused with leukocyte-reduced (LR) and non-leukocyte-reduced (N-LR) pRBC units at the Animal Hospital Zürich, University of Zürich, Switzerland between January 1, 2007, and December 17, 2018 were searched. Before 2014, only N-LR blood were transfused. After 2014, both LR and N-LR blood were available. A total of 339 canine patients were transfused with 413 pRBC units; 30.5% (126/413) were LR units and 69.5% (287/413) were N-LR. Data collected from medical records was analyzed using univariate and multivariate logistic regression. In the present study, TR occurred in 19.8% of pRBC units (25/126) with LR and in 17.7% (51/287) of pRBC with N-LR; p > 0.05. FNHTR occurred in 6.3% of pRBC units (8/126) with LR and in 4.5% (13/287) of those with N-LR; p > 0.05. There was no correlation between the occurrence of TR and discharge from hospital (p > 0.05). Crossmatching, immunosuppressive therapy, and age of the blood product were not associated with the frequency of TR; p > 0.05 for all. The duration of survival days was not related to the number of transfusions dogs received. In the present study, the leukocyte-depletion of transfused pRBC units was not associated with fewer TR nor to fewer FNHTR compared to N-LR units. Discharge of dogs from hospital was not dependent on the occurrence of TR.

140 A novel selective leukocyte depletion human whole blood model reveals the specific roles of monocytes and granulocytes in the cytokine response to Escherichia coli

140 A novel selective leukocyte depletion human whole blood model reveals the specific roles of monocytes and granulocytes in the cytokine response to Escherichia coli

Reduction of EpCAM-Positive Cells from a Cell Salvage Product Is Achieved by Leucocyte Depletion Filters Alone.

Intraoperative cell salvage reduces the need for allogeneic blood transfusion in complex cancer surgery, but concerns about the possibility of it re-infusing cancer cells have hindered its application in oncology. We monitored the presence of cancer cells on patient-salvaged blood by means of flow cytometry; next, we simulated cell salvage, followed by leucodepletion and irradiation on blood contaminated with a known amount of EpCAM-expressing cancer cells, assessing also residual cancer cell proliferation as well as the quality of salvaged red blood cell concentrates (RBCs). We observed a significant reduction of EpCAM-positive cells in both cancer patients and contaminated blood, which was comparable to the negative control after leucodepletion. The washing, leucodepletion and leucodepletion plus irradiation steps of cell salvage were shown to preserve the quality of RBCs in terms of haemolysis, membrane integrity and osmotic resistance. Finally, cancer cells isolated from salvaged blood lose their ability to proliferate. Our results confirm that cell salvage does not concentrate proliferating cancer cells, and that leucodepletion allows for the reduction of residual nucleated cells, making irradiation unnecessary. Our study gathers pieces of evidence on the feasibility of this procedure in complex cancer surgery. Nevertheless, it highlights the necessity of finding a definitive consensus through prospective trials.

COVID-19-associated pulmonary aspergillosis in immunocompetent patients: a virtual patient cohort study.

The opportunistic fungus Aspergillus fumigatus infects the lungs of immunocompromised hosts, including patients undergoing chemotherapy or organ transplantation. More recently however, immunocompetent patients with severe SARS-CoV2 have been reported to be affected by COVID-19 Associated Pulmonary Aspergillosis (CAPA), in the absence of the conventional risk factors for invasive aspergillosis. This paper explores the hypothesis that contributing causes are the destruction of the lung epithelium permitting colonization by opportunistic pathogens. At the same time, the exhaustion of the immune system, characterized by cytokine storms, apoptosis, and depletion of leukocytes may hinder the response to A. fumigatus infection. The combination of these factors may explain the onset of invasive aspergillosis in immunocompetent patients. We used a previously published computational model of the innate immune response to infection with Aspergillus fumigatus. Variation of model parameters was used to create a virtual patient population. A simulation study of this virtual patient population to test potential causes for co-infection in immunocompetent patients. The two most important factors determining the likelihood of CAPA were the inherent virulence of the fungus and the effectiveness of the neutrophil population, as measured by granule half-life and ability to kill fungal cells. Varying these parameters across the virtual patient population generated a realistic distribution of CAPA phenotypes observed in the literature. Computational models are an effective tool for hypothesis generation. Varying model parameters can be used to create a virtual patient population for identifying candidate mechanisms for phenomena observed in actual patient populations.

Measuring antigen expression of cancer cell lines and circulating tumour cells

When evaluating EpCAM-based enrichment technologies for circulating tumour cells (CTCs), the cell lines used should closely resemble real CTCs, meaning the EpCAM expression of CTCs needs to be known, but also the EpCAM expression of cell lines at different institutions and times is important. As the number of CTCs in the blood is low, we enriched CTCs through the depletion of leukocytes from diagnostic leukapheresis products of 13 prostate cancer patients and measured EpCAM expression using quantitative flow cytometry. Antigen expression was compared between multiple institutions by measuring cultures from each institution. Capture efficiency was also measured for one of the used cell lines. Results show CTCs derived from castration-sensitive prostate cancer patients have varying but relatively low EpCAM expression, with median expression per patient ranging from 35 to 89,534 (mean 24,993) molecules per cell. A large variation in the antigen expression of identical cell lines cultured at different institutions was found, resulting in recoveries when using the CellSearch system ranging from 12 up to 83% for the same cell line. We conclude that large differences in capture efficiency can occur while using the same cell line. To closely resemble real CTCs from castration-sensitive prostate cancer patients, a cell line with a relatively low EpCAM expression should be used, and its expression should be monitored frequently.

Alemtuzumab treatment exemplifies discordant immune effects of blood and cerebrospinal fluid in multiple sclerosis

Background and objectivesImmune responses in the central nervous system (CNS) are highly compartmentalized and cerebrospinal fluid (CSF) in particular often reflects CNS pathology better than peripheral blood. While CSF leukocytes are known to be distinct from blood, the immediate effects of peripheral leukocyte depletion on CSF leukocytes have not been studied in humans. MethodsWe here analyzed CSF and blood from two relapsing-remitting multiple sclerosis (RRMS) patients early after peripheral leukocyte depletion with the anti-CD52 antibody alemtuzumab compared to untreated RRMS and control patients using single cell RNA-sequencing. ResultsAs expected for alemtuzumab, most leukocyte lineages including T cells were synchronously depleted from CSF and blood, while - surprisingly - pDCs were maintained in CSF but depleted from blood by alemtuzumab. Transcriptionally, genes associated with migration were elevated only in the CSF after alemtuzumab. Predicted cellular interactions indicated a central role of pDCs and enhanced migration signaling in the CSF after alemtuzumab. DiscussionThe CSF and blood compartments are thus partially uncoupled, emphasizing that the CNS is only partially accessible even for treatments profoundly affecting the blood.

Drug Resistance Molecular Markers of Plasmodium falciparum and Severity of Malaria in Febrile Children in the Sentinel Site for Malaria Surveillance of Melen in Gabon: Additional Data from the Plasmodium Diversity Network African Network.

The objective of this study was to analyze the relationship between the frequency of artemisinin-based combination (ACT) drug resistance molecular markers and clinical forms of P. falciparum malaria and parasitemia. A cross-sectional study was carried out between January and April 2014 at the Operational Clinical Research Unit of Melen in febrile children aged 12 to 240 months with a Plasmodium sp. infection. A total of 3 mL of peripheral blood collected from an EDTA tube was used for leukocyte depletion. DNA mutation detection was performed by next generation sequencing (NGS). A total of 1075 patients were screened for malaria. Among them, 384 had a Plasmodium infection. P. falciparum mono-infection was found in 98.9% of the patients. Pfcrt-326T mutation was found in all isolates, while 37.9% had Pfmdr2-484I mutant allele. The highest median parasite densities were found in patients infected by parasites carrying the CVIET haplotype of the Pfcrt gene. The different genetic profiles found here, and their variations according to clinical and biological signs of severe malaria, are additional arguments for the surveillance of P. falciparum strains.

Oxidative stress and related metabolic alterations are induced in ex situ perfusion of donated hearts regardless of the ventricular load or leukocyte depletion

We sought to determine the role of donor blood circulating leukocytes in mediating oxidative stress and inflammation during normothermic ex situ heart perfusion (ESHP). Normothermic ESHP allows preservation of donated heart in a perfused, dynamic state, preventing ischemia. However, the cardiac function declines during ESHP, limiting the potential of this method for improvement of the outcomes of transplantation and expanding the donor pool. Extracorporeal circulation-related oxidative stress plays a critical role in the functional decline of the donor heart. Hearts from domestic pigs were perfused in working mode (WM, whole blood-based or leukocyte-depleted blood-based perfusate) or nonworking mode. Markers of oxidative stress and responsive glucose anabolic pathways were induced in the myocardium regardless of left ventricular load. Myocardial function during ESHP as well as cardioprotective mechanisms were preserved better in WM. Leukocyte-depleted perfusate did not attenuate tissue oxidative stress or perfusate proinflammatory cytokines and did not improve functional preservation. Although ESHP is associated with ongoing oxidative stress and metabolic alteration in the myocardium, preserved cardioprotective mechanisms in WM may exert beneficial effects. Leukocyte depletion of the perfusate may not attenuate inflammation and oxidative stress effectively or improve the functional preservation of the heart during ESHP.

Combined effects of granulocyte and monocyte adsorption apheresis and corticosteroids on ulcerative colitis.

Several new treatments for ulcerative colitis have been developed recently. The depletion of leukocytes by granulocyte and monocyte adsorption apheresis (GMA) was developed and adapted for patients with ulcerative colitis with rare adverse events. We investigated whether treatment with GMA and prednisolone (GMA + PSL) is more effective than PSL alone for patients with moderate to severe ulcerative colitis. Forty-seven patients with moderate to severe ulcerative colitis were retrospectively analyzed. Among the 47 patients, 27 received PSL, while 20 received GMA + PSL. The clinical activity of ulcerative colitis was evaluated using the Lichtiger clinical activity index (CAI) and serum levels of C-reactive protein. Mayo endoscopic score (MES) was used to examine endoscopic activity. The clinical remission rate was significantly higher in the GMA + PSL group than in the PSL group (65% vs 29.6%, p = 0.0206). The mucosal healing rate was also significantly higher in the GMA + PSL group than in the PSL group (60% vs 26%, p = 0.0343). The combination of GMA and steroids may be more effective than steroids alone for inducing clinical remission and mucosal healing in patients with moderate to severe ulcerative colitis.

Leukocyte Depletion and Size-Based Enrichment of Circulating Tumor Cells Using a Pressure-Sensing Microfiltration Device.

Considering the challenges in isolating circulating tumor cells (CTCs) pertaining to cellular stress and purity, we report the application of a blood microfiltration device as an optimal approach for noninvasive liquid biopsy to target CTCs. We experimentally analyzed the filtration behavior of the microfilter using pressure sensing to separate tumor cells from leukocytes in whole blood. This approach achieved an average recovery of >96% of the spiked tumor cells and depletion of >99% of total leukocytes. Furthermore, we carried out genomic profiling of the CTCs using the blood microfiltration device. The method was also applied in a clinical setting; DNA amplification was performed using a small number of microfiltered CTCs and epidermal growth factor receptor mutations were successfully detected to characterize the efficacy of molecularly targeted drugs against lung cancer. Overall, the proposed method can provide a tool for evaluating efficient filtration pressure to concentrate CTCs from whole blood.