Cytokines are critical coordinators of the immune response necessary for resolving bacterial and viral assaults on the immune system. In particular, the IL-12 family of cytokines are key players in the regulation of T cell responses. These responses are orchestrated by monocytes, macrophages, and dendritic cells which produce the members of the IL-12 family of cytokines in response to infection. IL-27 and IL-23 are two cytokines that are related to IL-12; these cytokines share homology at the subunit, receptor, and signalling levels. IL-12 is composed of p35 and p40 subunits, which, when combined together form the bioactive IL-12p70. IL-23 is composed of the IL-12p40 subunit as well as the IL-23p19 subunit, which shares homology with IL-12p35. IL-27 is composed of EBI3 and p28. These three cytokines activate similar members of the JAK/STAT signalling pathways as a result of homology in their receptor components. Production of these cytokines by activated monocytes, macrophages, and dendritic cells results in the activation and differentiation of T cells. In spite of their similarity, each of these cytokines has specific roles in the regulation of immune responses. IL-12 is required for the induction of IFN-gamma production, critical for the induction of Th1 cells. IL-27 has been shown to play a role in the induction of Th1 cells from naive T cells, whereas IL-23 has been demonstrated to play a key role in the induction of the newly described Th17 cells. Recently, a novel heterodimeric and anti-inflammatory cytokine composed of the IL-12p35 and EBI3 subunits has been identified as IL-35. The biological properties of the IL-12 family of cytokines, the signalling pathways mediated by these cytokines and their role in infection, inflammation, and autoimmune diseases will be the focus of this review.

IL-27 is a heterodimeric cytokine bridging innate and adaptive immunity by playing a role in the activation of naive T cells and in development of Th1 cells. Additionally, recent evidence supports a role for IL-27 in the activation of monocytic cells. Both pro-inflammatory and anti-inflammatory activities have been attributed to IL-27; however, the role played by IL-27 in the activation of human monocytic cells in terms of cytokine production has not been well described. Our results show that IL-27 is a strong inducer of proinflammatory cytokine and chemokine expression, including enhancement of IL-6, IP-10, MIP-1␣, MIP-1␤, and TNF-␣ expression in human primary monocytes. Furthermore, we observed that IL-27-induced cytokine and chemokine production was mediated by STAT1, STAT3, and NF-B activation. Understanding how IL-27 exerts its effects on monocytic cells will identify important molecular mechanisms in the regulation of immune responses, particularly in the modulation of monocyte activation.

Malaysia has recorded the highest number of COVID-19 cases in Southeast Asia with more than 35% of new COVID-19 cases linked to the Sri Petaling gathering, a Moslem missionary movement attended by more than 19 000 people of different nationalities, in March 2020 in Kuala Lumpur. From this cluster, 1701 samples have been tested positive out of 21 920 tests carried out. Thus, mass gathering during COVID-19 pandemic period should be banned to curb disease transmission.

A newly described cytokine, interleukin-27 (IL-27), that activates naive CD4 T cells, has recently been shown to be an anti-HIV cytokine. However, the effect of HIV infection on IL-27 expression has not been characterized. We found that clinical characteristics, including HIV viral load, hepatitis C virus coinfection, and CD4 T cell counts, were associated with changes in serum IL-27. Overall, our results suggest circulating HIV may suppress IL-27, a critical concept in treatment development with this cytokine.

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PurposeThe aim of this study was to investigate the potential of the synergetic triple therapeutic combination encompassing bismuth oxide nanoparticles (BiONPs), cisplatin (Cis), and high dose rate (HDR) brachytherapy with Ir-192 source in breast cancer and normal fibroblast cell line.MethodsIn vitro models of breast cancer cell lines (MCF-7, MDA-MB-231) and normal fibroblast cell line (NIH/3T3) were employed. Cellular localization and cytotoxicity studies were conducted prior to inspection on the radiosensitization effects and generation of reactive oxygen species (ROS) on three proposed radiosensitizers: BiONPs, Cis, and BiONPs-Cis combination (BC). The optimal, non-cytotoxic concentration of BiONPs (0.5 mM) and the 25% inhibitory concentration of Cis (1.30 µM) were applied. The radiosensitization effects were evaluated by using a 0.38 MeV Iridium-192 HDR brachytherapy source over a prescribed dose range of 0 Gy to 4 Gy.ResultsThe cellular localization of BiONPs was visualized by light microscopy and accumulation of the BiONPs within the vicinity of the nuclear membrane was observed. Quantification of the sensitization enhancement ratio extrapolated from the survival curves indicates radiosensitization effects for MCF-7 and MDA-MB-231 when treated with BiONPs, Cis, and BC. However, NIH/3T3 cells exhibited contradictive behavior as it only reacted towards the BC combination. Nonetheless, the MCF-7 cell line loaded with BC shows the highest SER of 4.29. ROS production analysis, on the other hand, shows that Cis and BC radiosensitizers generated the highest free radicals in comparison to BiONPs alone.ConclusionA BiONPs-Cis combination was unveiled as a novel approach that offers promising radiosensitization enhancement that will increase the efficiency of tumor control while preserving the normal tissue at a reduced dose. This data is the first precedent to prove the synergetic implication of BiONPs, Cis, and HDR brachytherapy that will be beneficial for future chemoradiotherapy strategies in cancer care.

The successful of transplantation is determined by the shared human leukocyte antigens (HLAs) and ABO blood group antigens between donor and recipient. In recent years, killer cell receptor [i.e., killer cell immunoglobulin-like receptor (KIR)] and major histocompatibility complex (MHC) class I chain-related gene molecule (i.e., MICA) were also reported as important determinants of transplant compatibility. At present, several different genotyping techniques (e.g., sequence specific primer and sequence based typing) can be used to characterize blood group, HLA, MICA and KIR and loci. These molecular techniques have several advantages because they do not depend on the availability of anti-sera, cellular expression and have greater specificity and accuracy compared with the antibody-antigen based typing. Nonetheless, these molecular techniques have limited capability to capture increasing number of markers which have been demonstrated to determine donor and recipient compatibility. It is now possible to genotype multiple markers and to the extent of a complete sequencing of the human genome using next generation sequencer (NGS). This high throughput genotyping platform has been tested for HLA, and it is expected that NGS will be used to simultaneously genotype a large number of clinically relevant transplantation genes in near future. This is not far from reality due to the bioinformatics support given by the immunogenetics community and the rigorous improvement in NGS methodology. In addition, new developments in immune tolerance based therapy, donor recruitment strategies and bioengineering are expected to provide significant advances in the field of transplantation medicine.

ObjectiveTo characterize the effect of HIV infection on IL-27-induced gene expression.DesignDuring HIV infection, cytokine expression and function become deregulated. IL-27 is an important modulator of inflammatory responses. Interestingly, IL-27 can inhibit HIV replication in T cells and monocytes, implicating IL-27 as a potential adjunct to anti-viral treatment. Our previous work demonstrated that circulating HIV may suppress IL-27 expression, therefore, this study, in continuation of our previous work, aimed to understand how HIV affects expression levels of the IL-27 receptor and downstream functions of IL-27.MethodsPeripheral blood mononuclear cells (PBMC) were isolated from whole blood of HIV negative and HIV positive (viremic) individuals to assess IL-27-induced gene expression by flow cytometry and ELISA. PBMC were also processed for monocyte enrichment to assess IL-27 receptor expression by flow cytometry and real-time PCR.ResultsExpression of the IL-27 receptor subunit, gp130, was upregulated in response to IL-27 in HIV negative individuals, however, in HIV positive individuals, this IL-27 response was diminished. Furthermore, we observed downregulation of IL-27-induced IL-6, TNF-α, and IL-10 expression in HIV positive subjects.ConclusionIn HIV infection, IL-27-induced gene expression was impaired, indicating HIV-mediated dysregulation of IL-27 functions occurs during HIV infection. This study provides evidence for new viral pathogenic mechanisms contributing to the widespread impairment of immune responses observed in HIV pathogenesis.