The effect of exosomes released from apheresis platelet concentrates under the impact of gamma irradiation and storage time upon platelet aggregation and hemostasis.

BACKGROUND: Blood components should be gamma-irradiated (γ-IR) in order to prevent transfusion-associated graft-versus-host disease. The aim of this study is to determine the effect of γ-IR and storage time on the exosomes released from apheresis platelet concentrates (aPC) and to investigate their impact on the maximum platelet aggregation (MPA) and hemostasis. MATERIALS AND METHODS: Eight units of aPC were included in this study. These were divided into four equal portions. Two portions were irradiated before storage while the other two were not. Thus, irradiated and non-irradiated aPC samples for storage Days 0 (D0) and 5 (D5) were obtained. Exosomes were isolated from these samples using a commercial kit and were evaluated to ascertain their parent cells by flow cytometry. For the following steps, exosomes were pooled according to their features. Pooled exosomes were then used for aggregometry and thromboelastography. RESULTS: Platelet-derived exosome (PD-EX) levels decreased in D5 compared to D0 in NI-aPC, whereas granulocyte-derived exosome (GD-EX) levels increased. Exosome pools had no effect on MPA compared to saline groups. Exosome pools decreased the time to initial fibrin formation (R), whereas they increased the rate of clot formation (α-angle) and coagulation index (CI) compared to saline groups. DISCUSSION: Storage time and γ-IR each have almost the opposite effects on PD-EX and GD-EX. Exosomes have no impact on MPA, but enhance the clot strength. The impact of exosomes on aPC quality and effectiveness can be ignored or considered as a positive effect.

Roles of novel IL-1 family (IL-36, IL-37, and IL-38) members in chronic brucellosis.

The secretion of interleukin (IL)-1 family cytokines is one of the most potent and earliest pro-inflammatory responses triggered by brucellosis. However, the roles of the most recently discovered IL-1 family members, IL-36, IL-37, and IL-38, in the transition into the chronic form of brucellos is remain largely unknown. Therefore, in this study, the roles of IL-36, IL-37, and IL-38 in brucella infections and their effects on the transition from the acute to chronic form of the disease were investigated. Using peripheral blood samples from 40 patients with acute brucellosis, 40 patients with chronic brucellosis, and 40 healthy control subjects, we analysed the serum concentrations of secreted IL-36, IL-37, and IL-38 using ELISA. The findings were confirmed by using RT-qPCR to analyse the mRNA levels of the genes encoding IL-36, IL-37, and IL-38 in peripheral blood mononuclear cells (PBMCs) from 10 randomly selected patients from each of the three groups. Our results showed that serum IL-37 (p < 0.001) and IL-38 (p < 0.001) concentrations were lower in patients with brucellosis than in the healthy controls. In addition, serum IL-37 and IL-38 concentrations were higher in the chronic patient group than in the acute patient group. The mRNA expression levels of IL-37 and IL1F10, genes that encode IL-38, did not affect serum cytokine secretion levels. This result suggests that the high secretion levels of IL-37 and IL-38 may be related to the progression into the chronic form of brucellosis. Our findings will aid in clarifying the mechanism of the transition of brucellosis from the acute to the chronic form of the disease.

The microRNA expression signature of CD4+ T cells in the transition of brucellosis into chronicity.

Brucellosis is a serious infectious disease that continues to be a significant cause of morbidity worldwide and across all ages. Despite early diagnosis and treatment, 10-30% of patients develop chronic brucellosis. Although there have been recent advances in our knowledge of Brucella virulence factors and hosts' immune response to the infection, there is a lack of clear data regarding how the infection bypasses the immune system and becomes chronic. The present study investigated immunological factors and their roles in the transition of brucellosis from an acute to a chronic infection in CD4+ T cells. CD4+ T cells sorted from peripheral blood samples of patients with acute or chronic brucellosis and healthy controls using flow cytometry as well as more than 2000 miRNAs were screened using the GeneSpring GX (Agilent) 13.0 miRNA microarray software and were validated using reverse transcription polymerase chain reaction (RT-qPCR). Compared to acute cases, the expression levels of 28 miRNAs were significantly altered in chronic cases. Apart from one miRNA (miR-4649-3p), 27 miRNAs were not expressed in the acute cases (p <0.05, fold change> 2). According to KEGG pathway analysis, these miRNAs are involved in the regulation of target genes that were previously involved in the MAPK signalling pathway, regulation of the actin cytoskeleton, endocytosis, and protein processing in the endoplasmic reticulum. This indicates the potential role of these miRNAs in the development of chronic brucellosis. We suggest that these miRNAs can be used as markers to determine the transition of the disease into chronicity. This is the first study of miRNA expression that analyses human CD4+ T cells to clarify the mechanism of chronicity in brucellosis.

Altered Expressions of miR-1238-3p, miR-494, miR-6069, and miR-139-3p in the Formation of Chronic Brucellosis.

Brucellosis is a zoonotic disease that is still endemic in developing countries. Despite early diagnosis and treatment of patients, chronic infections are seen in 10-30% of patients. In this study, we aimed to investigate the immunological factors that play roles in the transition of brucellosis from acute infection into chronic infection. Here, more than 2000 miRNAs were screened in peripheral blood mononuclear cells (PBMCs) of patients with acute or chronic brucellosis and healthy controls by using miRNA array, and the results of the miRNA array were validated through qRT-PCR. Findings were evaluated using GeneSpring GX (Agilent) 13.0 software and KEGG pathway analysis. Four miRNAs were expressed in the chronic group but were not expressed in acute and control groups. Among these miRNAs, the expression level of miR-1238-3p was increased while miR-494, miR-6069, and miR-139-3p were decreased (p < 0.05, fold change > 2). These miRNAs have the potential to be markers for chronic cases. The differentially expressed miRNAs and their predicted target genes involved in endocytosis, regulation of actin cytoskeleton, MAPK signaling pathway, and cytokine-cytokine receptor interaction and its chemokine signaling pathway indicate their potential roles in chronic brucellosis and its progression. It is the first study of miRNA expression analysis of human PBMC to clarify the mechanism of inveteracy in brucellosis.

[Investigation of the presence of HBV-DNA in isolated anti-HBc positive cases and their importance in blood banking]. / Izole anti-HBc pozitif olgularda HBV-DNA varliginin arastirilmasi ve bu olgularin kan bankaciligi açisindan önemi.

Despite the decrease in transfusion-transmitted hepatitis B virus (HBV), it is still one of the main problems in transfusion medicine. Recent studies have shown that HBV is transmissible to recipients from HBsAg negative donations. This study was aimed to detect anti-HBc, anti-HBs and HBV-DNA positivity in HBsAg negative cases and to determine whether a reconsideration is required for HBV screening policies in blood banking. In this study, anti-HBs and anti-HBc total was investigated in 9282 HBsAg negative donor samples by commercial ELISA (Orto-Clinical Diagnostics, Vitros, Brazil) system and HBV-DNA by real-time PCR method (QIAGEN, Artus 3000, Germany). In 9282 HBsAg negative samples, anti-HBc positivity rate was 18% (1679/9282). Anti-HBs negativity was detected in 15% (n=225) of these anti-HBc positive sera. Among the isolated anti-HBc positive (HBsAg negative, anti-HBc positive, anti-HBs negative) 225 serum samples 218 were investigated for HBV-DNA presence and one sample was found to be positive (0.45%). When the samples not tested due to insufficient serum amount were excluded, the total rate of isolated anti-HBc positivity in the study region was 2.5% (225/9107) and HBV-DNA positivity in the HBsAg negative group was 0.011% (1/9100). The annual number of blood donations in our center was about 21.000, thus the rate of HBV transmission from HBsAg negative donors could be estimated as 2.3 patients/year. Although the rate of HBV transmission due to HBV-DNA positivity among HBsAg negative blood donors is low, this risk should always be kept in mind in transfusion medicine.