No Differences in Levels of Circulating Progenitor Endothelial Cells or Circulating Endothelial Cells Among Patients Treated With Ticagrelor Compared With Clopidogrel During Non- ST -Segment-Elevation Myocardial Infarction

Background

Ticagrelor use during acute coronary syndromes demonstrated a decrease in all‐cause mortality in the PLATO (Platelet Inhibition and Patient Outcomes) trial. This effect has been attributed to a non–platelet‐derived improvement in endothelial function. The aim of this study was to determine differences in the number of endothelial progenitor cells and/or circulating endothelial cells found in peripheral blood in patients treated with either ticagrelor or clopidogrel during non–ST‐segment–elevation myocardial infarction.

Methods and Results

In this multicenter, randomized study (NCT02244710), patients were considered for inclusion after non–ST‐segment–elevation myocardial infarction whenever they were P2Y₁₂‐inhibitor naïve. Ticagrelor and clopidogrel were allocated at a 1:1 ratio. Blood samples for determining endothelial progenitor cells and circulating endothelial cells were extracted before the antiplatelet loading dose, 48 hours after presentation of index symptoms, and 1 month after the event. A multichannel cytometer was used for optimal cell characterization. A total of 96 patients fulfilled the inclusion criteria. Circulating endothelial cell levels corrected by white blood cells were as follows at baseline, 48 hours, and 1 month: 44 (28–64), 50 (33–63), and 38 (23–62) cells/mL, respectively, for clopidogrel and 38 (29–60), 45 (32–85), and 35 (24–71) cells/mL, respectively, for ticagrelor (P=0.6). Endothelial progenitor cell levels were 29 (15–47), 27 (15–33), and 18 (10–25) cells/mL, respectively, for clopidogrel and 20 (11–33), 22 (12–32), and 18 (11–29) cells/mL, respectively, for ticagrelor (P=0.9). No differences in intraindividual changes were found.

Conclusions

Patients treated with ticagrelor during non–ST‐segment–elevation myocardial infarction, in comparison to clopidogrel, showed similar levels of endothelial progenitor cells and circulating endothelial cells. These data suggest that the endothelial protective effect mediated by ticagrelor is not related to bone marrow physiology modulation.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02244710.

The effect of the lectin from Cherax quadricarinatus on its granular hemocytes

In crustaceans, lectins and hemocytes of the innate immune system provide the first line of defense. Although evidence points to the potential role of lectins in regulating hemocyte activity, the processes underlying the lectin activation have not been evaluated. In the present study, the receptor for CqL, a humoral lectin from Cherax quadricarinatus specific for galactose/sialic acid, was identified in a granular subset of hemocytes. The CqL receptor (CqLR) is a 490-kDa glycoprotein, composed of four identical 120-kDa subunits. As shown by immunohistochemistry, CqL at 7.5 μg/mL as optimal dose, after 2 min, induced, specifically on granular hemocytes, increased phosphorylation of serine (152%), threonine (192%), and tyrosine (242%) as compared with non-treated hemocytes; moreover, CqL induced increased generation of reactive oxygen species (ROS). Specific kinase inhibitors showed inhibition (P < 0.001) of ROS production induced by CqL. These results strongly suggest that CqL actively participated in the generation of ROS through kinases induced by a CqLR in a subset of granular hemocytes of the crayfish C. quadricarinatus. The results provide strong evidence that CqL activates, through specific granular hemocytes, receptors that modulate cellular functions in C. quadricarinatus.

Transient hemolysis due to anti-D and anti-A1 produced by engrafted donor's lymphocytes after allogeneic unmanipulated haploidentical hematopoietic stem cell transplantation

BACKGROUND

Development of de novo alloantibodies against recipient's red blood cell (RBC) antigens by engrafted donor's lymphocytes is a known phenomenon in the setting of allogeneic hematopoietic stem cell transplantation (HSCT). This situation is usually clinically insignificant. We report a case of early clinically relevant hemolytic anemia in a blood group A₁ D+ patient, due to a limited production of anti-D and anti-A₁ produced by nonpreviously sensitized newly engrafted donor's immune system.

CASE REPORT

A 31-year-old Caucasian woman, blood group A₁ , D+, with Hodgkin's lymphoma, received an unmanipulated haploidentical allogeneic peripheral blood HSCT after a nonmyeloablative conditioning regimen. Donor blood group was A₂ B, D-. The patient had an uneventful course until Day +34, when she developed clinically significant hemolytic anemia with a positive direct antiglobulin test. Anti-D and anti-A₁ produced by the donor-engrafted lymphocytes were detected both in serum and in eluate. The hemolysis produced an accelerated group change, turning the patient's ABO group into A₂ B 2 weeks after the detection of the alloantibodies. As the residual patient's RBCs progressively disappeared, anti-D and anti-A₁ production decreased and were not detected in serum by Day +41.

CONCLUSION

This case illustrates that de novo alloantibody production against ABO and D antigens by the newly engrafted donor's lymphocytes can occasionally cause clinically significant anemia. To our knowledge, this is the first case reported of clinically significant hemolytic anemia due to a transient anti-D anti-A₁ alloimmunization after T-cell-repleted haploidentical HSCT.

Sertoli Cells Induce Systemic Donor-Specific Tolerance in Xenogenic Transplantation Model

Cell therapy is a potentially powerful tool in the treatment of many grave disorders including leukemia, immune deficiencies, autoimmune diseases, and diabetes. However, finding matched donors is challenging and recipients may suffer from the severe complications of systemic immune suppression. Sertoli cells, when cotransplanted with both allo- and xenograft tissues, promote graft acceptance in the absence of systemic immunosuppression. How Sertoli cells do this is not, as yet, clearly defined. We have examined the ability of Sertoli cells to produce systemic immune tolerance. For this purpose, Sertoli cells were injected into an otherwise normal C57/BL6 mouse host via the lateral tail vein. No other immunosuppressive protocols were applied. Six to 8 weeks posttransplantation, blood was collected for analysis of cytokine levels. Tolerance to donor cells was determined by mixed lymphocytic culture, and production of T-cell-dependent antibody was determined by an in vitro anti-sheep red blood cell plaque-forming assay. Results showed a marked modulation of immune cytokines in the transplanted mouse host and donor-specific transplantation tolerance was achieved. Tolerant mouse lymphocytes maintained a competent humoral antibody response. Additionally, C57/BL6 mice transplanted with rat Sertoli cells tolerated rat skin grafts significantly longer than control non-Sertoli cell transplanted mice. We conclude that systemic administration of rat Sertoli cells across xenogenic barrier induces transplantation tolerance without altering systemic immune competence. These data suggest that Sertoli cells may be used as a novel and potentially powerful tool in cell transplantation therapy.

Use of eltrombopag for secondary immune thrombocytopenia in clinical practice

Eltrombopag is a second-line treatment in primary immune thrombocytopenia (ITP). However, its role in secondary ITP is unknown. We evaluated the efficacy and safety of eltrombopag in secondary ITP in daily clinical practice. Eighty-seven secondary ITP patients (46 with ITP secondary to autoimmune syndromes, 23 with ITP secondary to a neoplastic disease subtype: lymphoproliferative disorders [LPDs] and 18 with ITP secondary to viral infections) who had been treated with eltrombopag were retrospectively evaluated. Forty-four patients (38%) had a platelet response, including 40 (35%) with complete responses. Median time to platelet response was 15 days (95% confidence interval, 7-28 days), and was longer in the LPD-ITP group. Platelet response rate was significantly lower in the LPD-ITP than in other groups. However, having achieved response, there were no significant differences between the durable response of the groups. Forty-three patients (49·4%) experienced adverse events (mainly grade 1-2), the commonest being hepatobiliary laboratory abnormalities. There were 10 deaths in this case series, all of which were related to pre-existing medical conditions. In routine clinical practice, eltrombopag is effective and well-tolerated in unselected patients with ITP secondary to both immune and infectious disorders. However, the response rate in LPD-ITP is low.

Digestive Physiology of Octopus maya and O. mimus: Temporality of Digestion and Assimilation Processes

Digestive physiology is one of the bottlenecks of octopus aquaculture. Although, there are successful experimentally formulated feeds, knowledge of the digestive physiology of cephalopods is fragmented, and focused mainly on Octopus vulgaris. Considering that the digestive physiology could vary in tropical and sub-tropical species through temperature modulations of the digestive dynamics and nutritional requirements of different organisms, the present review was focused on the digestive physiology timing of Octopus maya and Octopus mimus, two promising aquaculture species living in tropical (22-30°C) and sub-tropical (15-24°C) ecosystems, respectively. We provide a detailed description of how soluble and complex nutrients are digested, absorbed, and assimilated in these species, describing the digestive process and providing insight into how the environment can modulate the digestion and final use of nutrients for these and presumably other octopus species. To date, research on these octopus species has demonstrated that soluble protein and other nutrients flow through the digestive tract to the digestive gland in a similar manner in both species. However, differences in the use of nutrients were noted: in O. mimus, lipids were mobilized faster than protein, while in O. maya, the inverse process was observed, suggesting that lipid mobilization in species that live in relatively colder environments occurs differently to those in tropical ecosystems. Those differences are related to the particular adaptations of animals to their habitat, and indicate that this knowledge is important when formulating feed for octopus species.

Supplementation of arachidonic acid rich oil in European sea bass juveniles (Dicentrarchus labrax) diets: Effects on leucocytes and plasma fatty acid profiles, selected immune parameters and circulating prostaglandins levels

The main objective of this study was to assess the effects of graded levels of dietary arachidonic acid (ARA), supplemented from alternative sources, on fatty acid composition of plasma and head kidney leucocytes of European sea bass (Dicentrarchus labrax). For that purpose, sea bass juveniles were fed four diets containing graded levels of ARA as follows: 0.5% (ARA0.5), 1% (ARA1), 2% (ARA2) and 4% (ARA4) during 60 days. At the end of the feeding trial fatty acid profiles of plasma and head kidney leucocytes were analyzed. Besides, plasma prostaglandins levels, head kidney leucocytes respiratory burst activity; peroxidase activity and phagocytic index were assayed. Reducing dietary ARA levels below 1% markedly reduced European sea bass growth performance. However, fish fed diet ARA0.5 tried to compensate this dietary ARA deficiency by a selective deposition of ARA on plasma and head kidney leucocytes, reaching similar levels to those fish fed diet ARA1 after 60 days of feeding. Nevertheless, head kidney phagocytic capacity was reduced as dietary ARA content in relation not only to variations on membrane composition but also to changes on fish basal prostaglandins levels. Results obtained demonstrated the importance to supply the necessary quantity n-6 LC-PUFA, and not only n-3 LC-PUFA levels, in European sea bass diets, in relation to not only growth performance but also immune system function.

Outcomes and infectious etiologies of febrile neutropenia in non-immunocompromised children who present in an emergency department

There are no unified protocols governing the management of healthy children with febrile neutropenia in the emergency department (ED). Conservative management is the norm, with admission and empirical broad-spectrum antibiotics prescribed, although viral infections are considered the most frequent etiology. The aim of this study was to describe the clinical outcomes and identified etiologies of unsuspected neutropenia in febrile immunocompetent children assessed in the ED. This was a retrospective study: well-appearing healthy children <18 years old with febrile moderate [absolute neutrophil count (ANC) 500-999 neutrophils ×10(9)/l] or severe (ANC <500 neutrophils ×10(9)/l) neutropenia diagnosed in ED between 2005 and 2013 were included. Patients newly diagnosed with hematologic or oncologic disease were excluded. We included 190 patients: 158 (83.2 %) with moderate and 32(16.8 %) with severe neutropenia. One hundred and one (53.2 %) were admitted; 48(47.5 %) with broad-spectrum antibiotics. The median length of stay was 3 days (IQR 3-5) and the median duration of neutropenia was 6 days (IQR 3-12). An infectious agent was identified in 23(12.1 %); 21 (91.3 %) were viruses. Four (2.1 %) children had a serious bacterial infection (SBI): urinary tract infection and lobar pneumonia (two cases each). All blood cultures performed (144; 75.8 %) were negative. Over the 1-year follow-up, one or several blood tests were performed on 167 patients (87.9 %); two (1.2 %) were diagnosed with autoimmune chronic neutropenia. Previously healthy children with moderate or severe febrile neutropenia have a low risk of SBI and a favorable clinical outcome. Less aggressive management could be carried out in most of them. Although chronic hematological diseases are infrequently diagnosed, serial ANC are necessary to detect them.

Eltrombopag safety and efficacy for primary chronic immune thrombocytopenia in clinical practice

BACKGROUND

Eltrombopag is effective and safe in chronic immune thrombocytopenia (ITP). However, clinical trials may not accurately reflect what happens in clinical practice. We evaluated the efficacy and safety of eltrombopag in primary chronic ITP in a real-world setting.

METHODS

A total of 164 primary patients with chronic ITP from 40 Spanish centers, who had been treated with eltrombopag, were retrospectively evaluated.

RESULTS

The median age of our cohort (72% women) was 63 yr (interquartile range, IQR, 45-75 yr). The median time with ITP diagnosis was 81 months (IQR, 30-192 months). The median number of therapies prior to eltrombopag was 3 (IQR, 2-4). At the time of eltrombopag start, 45 patients (30%) were receiving concomitant treatment for ITP. Forty-six patients (30%) had bleeding signs/symptoms the month before the treatment started. The median platelet count at eltrombopag initiation was 22 × 10(9) /L (IQR, 8-39 × 10(9) /L). A total of 135 patients (88.8%) achieved a platelet response. The median time to platelet response was 12 d (95% CI, 9-13 d). Maintained platelet response rate during the 15-month period under examination was 75.2%. Twenty-eight patients (18.4%) experienced adverse events, mainly grades 1-2.

CONCLUSION

Eltrombopag is highly effective and well tolerated in unselected patients with primary chronic ITP.

Inhibitory killer cell immunoglobulin-like receptor (iKIR) mismatches improve survival after T-cell-repleted haploidentical transplantation

Alloreactivity triggered by interaction between killer cell immunoglobulin-like receptors (KIRs) and natural killer (NK) cells plays a role in the graft-versus-tumor effect after hematopoietic stem cell transplantation (SCT). Our aim in this study was to evaluate this role in the setting of T-cell-repleted haploidentical SCT with postinfusion high-dose cyclophosphamide (PT-Cy). We included 33 patients. Among patient-donor pairs with at least 1 inhibitory KIR (iKIR) gene mismatch, event-free survival (EFS) and cumulative incidence of relapse 1 year after transplant were significantly better (85% vs. 37% [P = 0.008] and 18% vs. 46% [P = 0.041], respectively). A subanalysis in 12 patients with Hodgkin's lymphoma (HL) showed an improvement in EFS 1 year after transplant in those patients with KIR ligand mismatch (100% vs. 25%, P = 0.012), although overall survival (OS) was not affected (85% vs. 80%, P = 0.2). Eight of 12 patient-donors pairs presented iKIR mismatches. Of note, this outcome was better in the small subgroup, both for EFS (100% vs. 25%, P = 0.012) and for OS (100% vs. 37%, P = 0.004). Our data suggest that in the setting of T-cell-repleted haploidentical SCT with PT-Cy, iKIR mismatch is associated with improved survival, with particularly good results for both iKIR and KIR ligand mismatches in patients with HL.

Successful discontinuation of eltrombopag after complete remission in patients with primary immune thrombocytopenia

Eltrombopag is effective and safe in immune thrombocytopenia (ITP). Some patients may sustain their platelet response when treatment is withdrawn but the frequency of this phenomenon is unknown. We retrospectively evaluated 260 adult primary ITP patients (165 women and 95 men; median age, 62 years) treated with eltrombopag after a median time from diagnosis of 24 months. Among the 201 patients who achieved a complete remission (platelet count >100 × 10(9) /l), eltrombopag was discontinued in 80 patients. Reasons for eltrombopag discontinuation were: persistent response despite a reduction in dose over time (n = 33), platelet count >400 × 10(9) /l (n = 29), patient's request (n = 5), elevated aspartate aminotransferase (n = 3), diarrhea (n = 3), thrombosis (n = 3), and other reasons (n = 4). Of the 49 evaluable patients, 26 patients showed sustained response after discontinuing eltrombopag without additional ITP therapy, with a median follow-up of 9 (range, 6-25) months. These patients were characterized by a median time since ITP diagnosis of 46.5 months, with 4/26 having ITP < 1 year. Eleven patients were male and their median age was 59 years. They received a median of 4 previous treatment lines and 42% were splenectomized. No predictive factors of sustained response after eltrombopag withdrawal were identified. Platelet response following eltrombopag cessation may be sustained in an important percentage of adult primary ITP patients who achieved CR with eltrombopag. However, reliable markers for predicting which patients will have this response are needed.

Use of eltrombopag after romiplostim in primary immune thrombocytopenia

The thrombopoietin receptor agonists (THPO-RAs), romiplostim and eltrombopag, are effective and safe in immune thrombocytopenia (ITP). However, the value of their sequential use when no response is achieved or when adverse events occur with one THPO-RA has not been clearly established. Here we retrospectively evaluated 51 primary ITP adult patients treated with romiplostim followed by eltrombopag. The median age of our cohort was 49 (range, 18-83) years. There were 32 women and 19 men. The median duration of romiplostim use before switching to eltrombopag was 12 (interquartile range 5-21) months. The reasons for switching were: lack of efficacy (n = 25), patient preference (n = 16), platelet-count fluctuation (n = 6) and side-effects (n = 4). The response rate to eltrombopag was 80% (41/51), including 67% (n = 35) complete responses. After a median follow-up of 14 months, 31 patients maintained their response. Efficacy was maintained after switching in all patients in the patient preference, platelet-count fluctuation and side-effect groups. 33% of patients experienced one or more adverse events during treatment with eltrombopag. We consider the use of eltrombopag after romiplostim for treating ITP to be effective and safe. Response to eltrombopag was related to the cause of romiplostim discontinuation.

Sustained response after discontinuation of short-and medium-term treatment with eltrombopag in patients with immune thrombocytopenia

Eltrombopag is effective and safe in chronic immune thrombocytopenia (ITP) patients not responding to previous therapy. However, when eltrombopag is discontinued, platelet counts usually return to baseline within 2 weeks. Here, we describe the clinical characteristics of the, to the best of our knowledge, largest case series of patients with ITP, who presented sustained responses after discontinuing eltrombopag (n = 12). The median time from diagnosis to eltrombopag initiation was 24 months (range, 1-480). The median number of prior therapies was 5 (range, 1-7), and the median duration of eltrombopag treatment was 5 months (range, 1-13). Three patients received eltrombopag for only 1 month. The treatment was well-tolerated. The median (range) follow-up of this case series was of 7 months (6-20), during which all patients maintained a safe platelet count without the need for anti-ITP treatment. The communication of such cases may support the conduction of new studies to investigate which predictive factors could identify ITP patients with sustained responses after discontinuing eltrombopag without additional therapy. The need of long-term use of eltrombopag should be re-examined.

Epidemiological study of Clostridium difficile infection in critical patients admitted to the Intensive Care Unit

Data on the epidemiology of infections caused by Clostridium difficile (CDI) in critically ill patients are scarce and center on studies with a limited time framework and/or epidemic outbreaks.

OBJECTIVE

To describe the characteristics and risk factors of critically ill patients admitted to the ICU with CDI, as well as the treatments used for the control of such infections.

MATERIAL AND METHODS

A retrospective study was made of patients included in the ENVIN-ICU registry with CDI in 2012. Patients were followed up to 72 h after discharge from the ICU. A case report form was used to record the following data: demographic variables, risk factors related to CDI, treatment and outcome. Infections were classified as community-acquired, nosocomial out-ICU and nosocomial in-ICU, according to the day on which Clostridium difficile isolates were obtained. Infection rates as episodes per 10,000 days of ICU stay are presented. The global in-ICU and hospital mortality rates were calculated.

RESULTS

Sixty-eight episodes of CDI in 33 out of a total of 173 ICUs participating in the registry were recorded (19.1%) (2.1 episodes per 10,000 days of ICU stay). Forty-five patients were men (66.2%), with a mean (SD) age of 63.4 (16.4) years, a mean APACHE II score on ICU admission of 19.9 (7.4), and an underlying medical condition in 44 (64.7%). Sixty-two patients (91.2%) presented more than 3 liquid depositions/day, 40 (58.8%) in association with severe sepsis or septic shock. Community-acquired infection occurred in 13 patients (19.1%), nosocomial out-ICU infection in 13 (19.1%), and in-ICU infection in 42 (61.8%). Risk factors included age>64 years in 39 cases (57.4%), previous hospital admission (3 months) in 32 (45.6%), use of antimicrobials (previous 7 days) in 57 (83.8%), enteral nutrition in 23 (33.8%), and the use of H2 inhibitors in 39 (57.4%). Initial combined treatment was administered to 18 patients (26.5%). Metronidazole was used in 60 (88.2%) and vancomycin in 31 (45.6%). The in-ICU mortality rate was 25.0% (n=17), with a hospital mortality 27.9% (n=19).

CONCLUSIONS

The rate of ICD in ICU patients is low, the infection affects severely ill patients, and is associated with high mortality. The presence of CDI is a marker of poor prognosis.