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Midkine (MK) and pleiotrophin (PTN) belong to the same family of cytokines. They have similar sequences and functions. Both have important roles in cellular proliferation, tumors, and diseases. They regulate and are expressed by some immune cells. We have recently demonstrated MK production by some human innate antigen-presenting cells (iAPCs), i.e., monocyte-derived dendritic cells (MDDCs) and macrophages stimulated through Toll-like receptor (TLR)-4, and plasmacytoid dendritic cells (pDCs) stimulated through TLR 7. While PTN production was only documented in tissue macrophages. TLRs 3, 7, 8, and 9 are nucleic acid sensing (NAS) TLRs that detect nucleic acids from cell damage and infection and induce iAPC responses. We investigated whether NAS TLRs can induce MK and PTN production by human iAPCs, namely monocytes, macrophages, MDDCs, myeloid dendritic cells (mDCs), and pDCs. Our results demonstrated for the first time that PTN is produced by all iAPCs upon TLR triggering (p < 0.01). IAPCs produced more PTN than MK (p < 0.01). NAS TLRs and iAPCs had differential abilities to induce the production of MK, which was induced in monocytes and pDCs by all NAS TLRs (p < 0.05) and in MDDCs by TLRs 7/8 (p < 0.05). TLR4 induced a stronger MK production than NAS TLRs (p ≤ 0.05). Monocytes produced higher levels of PTN after differentiation to macrophages and MDDCs (p < 0.05). The production of MK and PTN differs among iAPCs, with a higher production of PTN and a selective induction of MK production by NAS TLR. This highlights the potentially important role of iAPCs in angiogenesis, tumors, infections, and autoimmunity through the differential production of MK and PTN upon TLR triggering. [ABSTRACT FROM AUTHOR]

The cytokine midkine (MK) is a growth factor that is involved in different physiological processes including tissue repair, inflammation, the development of different types of cancer and the proliferation of endothelial cells. The production of MK by primary human macrophages and monocyte-derived dendritic cells (MDDCs) was never described. We investigated whether MK is produced by primary human monocytes, macrophages and MDDCs and the capacity of macrophages and MDDCs to modulate the proliferation of endothelial cells through MK production. The TLR stimulation of human monocytes, macrophages and MDDCs induced an average of ≈200-fold increase in MK mRNA and the production of an average of 78.2, 62, 179 pg/ml MK by monocytes, macrophages and MDDCs respectively (p < 0.05). MK production was supported by its detection in CD11c+ cells, CLEC4C+ cells and CD68+ cells in biopsies of human tonsils showing reactive lymphoid follicular hyperplasia. JSH-23, which selectively inhibits NF-κB activity, decreased the TLR-induced production of MK in PMBCs, macrophages and MDDCs compared to the control (p < 0.05). The inhibition of MK production by macrophages and MDDCs using anti-MK siRNA decreased the capacity of their supernatants to stimulate the proliferation of endothelial cells (p = 0.01 and 0.04 respectively). This is the first study demonstrating that the cytokine MK is produced by primary human macrophages and MDDCs upon TLR triggering, and that these cells can stimulate endothelial cell proliferation through MK production. Our results also suggest that NF-κB plays a potential role in the production of MK in macrophages and MDDCs upon TLR stimulation. The production of MK by macrophages and MDDCs and the fact that these cells can enhance the proliferation of endothelial cells by producing MK are novel immunological phenomena that have potentially important therapeutic implications. [ABSTRACT FROM AUTHOR]

Background: Bone marrow mononuclear cells have been successfully utilized for numerous regenerative purposes. In the current study, patients suffering from erectile dysfunction (ED) unresponsive to phosphodiesterase 5 inhibitors were administered autologous bone marrow concentrate delivered intracavernously utilizing a point of care FDA cleared medical device.Methods: A total of 40 patients were treated in the primary trial and 100 in the clinical registry, with the longest follow up of 12 months.Results: Minimal treatment associated adverse effects where observed related to short term bruising at the site of harvest or injection. No long-term adverse events were noted related to the intervention. Mean improvements in IIEF-5 score were 2 in the Caverstem 1.0 low dose group, 3 in the high dose Caverstem 1.0 group and 9 in the Caverstem 2.0 group. Furthermore, improvements peaked by 3 months and maintained at 6 months follow-up.Conclusion: These data support the safety and efficacy of point of care, minimally to non-manipulated, non-expanded bone marrow concentrate for the treatment of ED. Trial registration Funded by Creative Medical Health, Inc.; Clinicaltrials.gov number: NCT03699943; https://clinicaltrials.gov/ct2/show/NCT03699943?term=caverstem&rank=1; initially registered December 12, 2015. [ABSTRACT FROM AUTHOR]

The role of the innate immune response in detecting RNA viruses is crucial for the establishment of proper inflammatory and antiviral responses. Different receptors, known as pattern recognition receptors (PRRs), are present in the cytoplasm, endosomes, and on the cellular surface. These receptors have the capacity to sense the presence of viral nucleic acids as pathogen-associated molecular patterns (PAMPs). This recognition leads to the induction of type 1 interferons (IFNs) as well as inflammatory cytokines and chemokines. In this review, we provide an overview of the significant involvement of cellular RNA helicases and Toll-like receptors (TLRs) 3, 7, and 8 in antiviral immune defenses. [ABSTRACT FROM AUTHOR]

Background There are contradictory reports on the effects of obstructive sleep apnea (OSA) on the immune system. In order to clarify the effect of OSA on the different components of the immune system, we studied the association of OSA with changes in cytokine and chemokine levels, proliferative patterns of CD4 and CD8 T lymphocytes as well as NK cells ex vivo and neutrophil functions. Methods We investigated the association of OSA with potential alterations in 14 Th1/Th2 and inflammatory cytokines and chemokines, CD4 and CD8 T cells, NK cells, and the NADPH oxidase activation and phagocytic functions in neutrophils. Results Our results suggest that the increase in CD4 T cell frequency in OSA is associated with an increased expression of the nuclear protein Ki67 ( p < 0.05; power > 0.8), and is correlated with the levels of IL-1β ( p < 0.05; power > 0.8). The levels of IL-1β as well as IL-6 showed a potential increase, while the levels of IFN-γ ( p < 0.05; power > 0.8) and the ratio IFN-γ/IL-4 in the blood were possibly decreased in OSA. Additionally, we observed a potential increase in the expression of Ki67 in CD8 hi and CD8 lo NK cells ( p < 0.05; power > 0.8). Our results also suggest that neutrophils have a decreased capacity to phagocytose bacteria and activate NADPH oxidase in OSA patients ( p < 0.05; power > 0.8). Conclusion OSA may be associated with inflammatory and pro-Th2 immune responses, an increased proliferative potential of NK and CD4 T cells and a decreased capacity of neutrophils to phagocytose bacteria and produce ROS. [ABSTRACT FROM AUTHOR]

Background: The failure to establish potent anti-HBV T cell responses suggests the absence of an effective innate immune activation. Kupffer cells and liver-infiltrating monocytes/macrophages have an essential role in establishing anti-HBV responses. These cells express the costimulatory molecules CD80 and CD86. CD80 expression on antigen-presenting cells (APCs) induces Th1 cell differentiation, whereas CD86 expression drives the differentiation towards a Th2 profile. The relative expression of CD80, CD86 and PD-L1 on APCs, regulates T cell activation. Few studies investigated CD80 and CD86 expression on KCs and infiltrating monocytes/macrophages in HBV-infected liver and knowledge about the expression of PD-L1 on these cells is controversial. The expression of these molecules together in CD68+ cells has not been explored in HBV-infected livers. Methods: Double staining immunohistochemistry was applied to liver biopsies of HBV-infected and control donors to explore CD80, CD86 and PD-L1 expression in the lobular and portal areas. Results: Chronic HBV infection was associated with increased CD68+CD86+ cell count and percentage in the lobular areas, and no changes in the count and percentage of CD68+CD80+ and CD68+PD-L1+ cells, compared to the control group. While CD68+CD80+ cell count in portal areas correlated with the fibrosis score, CD68+CD80+ cell percentage in lobular areas correlated with the inflammation grade. Conclusion: The upregulation of CD86 but not CD80 and PD-L1 on CD68+ cells in HBV-infected livers, suggests that these cells do not support the induction of potent Th1. Moreover, the expression of CD80 on CD68+ cells correlates with liver inflammation and fibrosis. [ABSTRACT FROM AUTHOR]

Aim: The lack of potent innate immune responses during HCV infection might lead to a delay in initiating adaptive immune responses. Kupffer cells (KCs) and liver-infiltrating monocytes/macrophages (CD68+ cells) are essential to establish effective anti-HCV responses. They express co-stimulatory molecules, CD80 and CD86. CD86 upregulation induces activator responses that are then potentially regulated by CD80. The relative levels of expression of CD80, CD86 and the inhibitory molecule, PD-L1, on CD68+ cells modulate T cell activation. A few studies have explored CD80 and PD-L1 expression on KCs and infiltrating monocytes/macrophages in HCV-infected livers, and none investigated CD86 expression in these cells. These studies have identified these cells based on morphology only. We investigated the stimulatory/inhibitory profile of CD68+ cells in HCV-infected livers based on the balance of CD80, CD86 and PD-L1 expression. Methods: CD80, CD86 and PD-L1 expression by CD68+ cells in the lobular and portal areas of the liver of chronic HCV-infected (n = 16) and control (n = 14) individuals was investigated using double staining immunohistochemistry. Results: The count of CD68+ KCs in the lobular areas of the HCV-infected livers was lower than that in the control (p = 0.041). The frequencies of CD68+CD80+ cells and CD68+PD-L1+ cells in both lobular and total areas of the liver were higher in HCV-infected patients compared with those in the control group (p = 0.001, 0.031 and 0.007 respectively). Moreover, in the lobular areas of the HCV-infected livers, the frequency of CD68+CD80+ cells was higher than that of CD68+CD86+ and CD68+PD-L1+ cells. In addition, the frequencies of CD68+CD80+ and CD68+CD86+ cells were higher in the lobular areas than the portal areas. Conclusions: Our results show that CD68+ cells have an inhibitory profile in the HCV-infected livers. This might help explain the delayed T cell response and viral persistence during HCV infection. [ABSTRACT FROM AUTHOR]

Sleep is an imperative physiological aspect that plays a vital role in maintaining hormonal and humeral functions of the body and hence a healthy life. Circadian rhythms are daily oscillations in human activities and physiology that prepare human beings to better react to and anticipate challenges in the surrounding environment, which are a consequence of diurnal changes of day and night. The sleep/wake cycle is one of the most prominent manifestations of the circadian rhythm and communicates tightly with the immune system with daily oscillation of immunity. Sleep deprivation is now recognized as a common condition inherent to modern society, and it is detrimental to certain body functions, particularly immune function. The aim of this review is to explore the role of sleep in maintaining a healthy immune system during the COVID-19 pandemic. The review discusses sleep-regulatory substances that are linked to host defense mechanisms such as interleukin-1β, interleukin-6, tumor necrosis factor alpha, and interferon gamma. Cytokine levels also fluctuate with sleep/wake homeostasis and our review explores the relationship between sleep and cytokines and proposed therapeutics. The review will also cover sleep and immune response in children, adolescents, and healthcare workers, and finally it will touch on the effect of obstructive sleep apnea on immune response and the severity of COVID-19. [ABSTRACT FROM AUTHOR]

The article reports on the chromosomal locations of mcr-1 and blaCTX-M-15 in fluoroquinolone-resistant Escherichia coli ST410. It says that extended-spectrum beta-lactamase (ESBL)-producing and carbapenemase-producing isolates obtained from livestock and a human in Germany that harbored the mcr-1 gene were described in the past.

Guideline-directed medical therapy (GDMT) is crucial in reducing mortality in patients with heart failure with heart rate lowering by a beta blocker (BB) being an important therapeutic concept. We aimed to assess the usefulness of a wearable cardioverter/defibrillator (WCD) to provide detailed information about heart rate for managing patients with reduced left ventricular ejection fraction (LVEF) and symptoms of heart failure and to correlate mortality with the mean heart rate. A total of 4509 consecutive patients (mean age: 59 + 13 years, 88% male) were analyzed retrospectively. All patients had reduced LVEF and were prescribed a WCD for protection from sudden cardiac death (SCD) during GDMT uptitration awaiting LVEF recovery. The device continuously measured nighttime and daytime HR at the beginning and end of WCD use. Patients who died during wear time had significantly higher HRs compared with survivors: daytime beginning of use (BOU), 80 ± 15 bpm vs. 76 ± 13, p < 0.01; nighttime BOU, 76 ± 14 vs. 69 ± 13, p < 0.0001; daytime end of use (EOU), 84 ± 20 vs. 73 ± 13, p < 0.0001; nighttime EOU, 80 ± 20 vs. 65 ± 12, p < 0.0001). In conclusion, HR monitoring with a WCD yields important prognostic information and may assist in optimal usage of BB in patients with low LVEF. [ABSTRACT FROM AUTHOR]

Objectives: Identification of the high risk alleles, genotypes and haplotypes of the human leukocyte antigens (HLA) in different populations is beneficial for understanding their roles in type 1 diabetes (T1D) pathogenesis and intervention practices. This study aimed to identify T1D-associated HLA gene alleles in the Omani population. Methods: The present case-control study included 73 diabetic seropositive children (mean age 9.08 ± 3.27 years) attending the paediatric clinic at Sultan Qaboos University Hospital in Muscat, Oman, and 110 healthy controls. HLA--A, -B, -C, -DRB1 and -DQB1 genes were genotyped using a sequence-specific primer polymerase chain reaction (SSP-PCR). Results: Two HLA class I alleles (B*08, B*58) and three class II alleles (DQB1*02, DRB1*03 and DRB1*04) were associated with T1D susceptibility, while one class I (B*51) and three class II (DQB1*05, DQB1*06 and DRB1*16) alleles were associated with T1D protection. HLA-DRB1*03 and DQB1*02 alleles showed the strongest risk association among all alleles. Six DRB1 residues (E9, S11, S13, Y30, V70 and K71) were significantly associated with T1D susceptibility. Heterozygous genotypes, HLA-DRB1*03/*04 and DQB1*02/*03 were significantly associated with T1D susceptibility (P <0.0001, odds ratio [OR] = 63.21 and P = 0.02, OR = 3.63, respectively). Furthermore, a significant combined action of DRB1*03-DQB1*02 haplotype in T1D risk (P = 0.000176, OR = 15) and DRB1*16-DQB1*05 haplotype in protection (P = 0.0312, OR = 0.48) was detected. Conclusion: Known HLA class II gene alleles are associated with T1D in Omani children. [ABSTRACT FROM AUTHOR]

Around 15–30% of AIDS patients fail to recover their CD4 + T cell levels following combined antiretroviral therapy despite successful inhibition of HIV-1 replication. The exact reasons for this immune recovery failure are not completely understood. HLA alleles are among the candidate that may explain this failure. A total of 65 adult AIDS patients, with viral load of <50 copies per ml were investigated. Viral load and CD4 T cells counts were performed following standard techniques. HLA genotyping was performed using PCR-SSP technique. The Statistical Package for Social Sciences (SPSS version 19) was used for data processing and analysis. A significantly higher proportion of poor immune responders were carrying HLA-A68 (4.8% compared to 25.0%, P = 0.025) and HLA-B15 (2.4% compared to 20.8%, P = 0.023). The etiological fraction (Efe%) among carriers of HLA-A68 was 57.89% (95% CI = 26.79, 75.79) and was 61.35% (95% CI = 35.33, 76.91) among carriers of HLA-B15 . [ABSTRACT FROM AUTHOR]

Beractant, a natural surfactant, induces an antifibrogenic phenotype and apoptosis in normal human lung fibroblasts (NHLF). As intracellular Ca2+ signalling has been related to programmed cell death, we aimed to assess the effect of beractant on intracellular Ca2+ concentration ([Ca2+]i) in NHLF in vitro. Cultured NHLF were loaded with Fura-2 AM (3 μM) and Ca2+ signals were recorded by microfluorimetric techniques. Beractant causes a concentration-dependent increase in [Ca2+]i with a EC50 of 0.82 μg/ml. The application of beractant, at a concentration of 500 μg/ml, which has been shown to exert an apoptotic effect in human fibroblasts, elicited different patterns of Ca2+ signals in NHLF: a) a single Ca2+ spike which could be followed by b) Ca2+ oscillations, c) a sustained Ca2+ plateau or d) a sustained plateau overlapped by Ca2+ oscillations. The amplitude and pattern of Ca2+ transients evoked by beractant were dependent on the resting [Ca2+]i. Pharmacological manipulation revealed that beractant activates a Ca2+ signal through Ca2+ release from intracellular stores mediated by phospholipase Cβ (PLCβ), Ca2+ release from inositol 1,4,5-trisphosphate receptors (IP3Rs) and Ca2+ influx via a store-operated pathway. Moreover, beractant-induced Ca2+ release was abolished by preventing membrane depolarization upon removal of extracellular Na+ and Ca2+. Finally, the inhibition of store-operated channels prevented beractant-induced NHLF apoptosis and downregulation of α1(I) procollagen expression. Therefore, beractant utilizes SOCE to exert its pro-apoptotic and antifibrinogenic effect on NHLF. [ABSTRACT FROM AUTHOR]