Memory Th1/Th2 cell generation controlled by Schnurri-2

Characterization of prostanoids response to Bordetella pertussis antigen BscF and Tdap in LPS-challenged monocytes

Prostanoids are potent inflammatory mediators that play a regulatory role in the innate immune activation of the adaptive immune response to determine the duration of protection against infection. We aim to quantify the modulation of prostanoids profiles in lipopolysaccharide (LPS)-stimulated THP-1 cells treated with the novel pertussis antigen BscF. We compared the effect with pertussis antigens present in the current Tdap vaccine to understand the immunomodulatory effect that might contribute to the diminished Tdap vaccine effectiveness. The inflammatory challenge with LPS induced a robust elevation of most prostanoid family members compared to the control treatment. Treatment with BscF and Tdap significantly reduced the LPS-stimulated elevation of prostaglandins (PGs) D2, E2, and F2α, as well as thromboxane (TX) A2 levels. An opposite trend was observed for PGI2, as both antigens accelerated the LPS-stimulated upregulation. Further, we quantified cyclooxygenases (COXs) that catalyze the biosynthesis of prostanoids and found that both antigens significantly reduced LPS-stimulated COX-1 and COX-2, demonstrating that the waning of acellular pertussis vaccines' protective immunity may be due to other downstream enzymes not related to COXs. Our present study validates the potential role of BscF as an adjuvant, resulting in the next-generation pertussis vaccine discovery.

Protective effect of Asarum sieboldii essential oil on ovalbumin induced allergic rhinitis in rat

BACKGROUND

The study was aimed to investigate the protective effect of Asarum sieboldii Miq. essential oil (AEO) on ovalbumin (OVA)-induced allergic rhinitis (AR) in rats.

METHODS AND RESULTS

Sixty Sprague-Dawley male rats were randomly divided into six groups (n=10): control, model, cetirizine (Cet, 4.65 g/kg), and AEO (0.5, 1.5, 3 g/kg) groups. All animals except the control group received repeated intranasal instillation with 20 μl of 20% OVA in Al(OH)3 saline solvent for 15 days. The control group was intranasally instilled with 5 mg/ml of Al(OH)3 instead of the same procedure. In the 15 days, Cet and AEO were orally administrated for 28 days. At the end of the drug administration, 20 μl of 5% OVA was given to animals to stimulate allergic reaction, then the rat behavioral detection, assessment of the patho-morphological changes in nasal mucosa, and the serum biomarkers were determined. The result showed that AEO could significantly reduce the amount of nasal secretions, sneezing, and the degree of nasal scratching in AR rats with EC50 = 1.5 and 2.8 g/kg, respectively. The degree of nasal mucosal inflammation in AEO group improved, the levels of immunoglobulin E (IgE), histamine, IL-4, IL-5, IL-17 were decreased, and the level of IFN-γ was increased obviously with EC50 = 2 g/kg.

CONCLUSION

The study suggested that the possible mechanism might be related with the inhibition of histamine release and regulation of the cytokine levels, which plays an important role in the treatment of AR.

Ribosome-Profiling Reveals Restricted Post Transcriptional Expression of Antiviral Cytokines and Transcription Factors during SARS-CoV-2 Infection

The global COVID-19 pandemic caused by SARS-CoV-2 has resulted in over 2.2 million deaths. Disease outcomes range from asymptomatic to severe with, so far, minimal genotypic change to the virus so understanding the host response is paramount. Transcriptomics has become incredibly important in understanding host-pathogen interactions; however, post-transcriptional regulation plays an important role in infection and immunity through translation and mRNA stability, allowing tight control over potent host responses by both the host and the invading virus. Here, we apply ribosome profiling to assess post-transcriptional regulation of host genes during SARS-CoV-2 infection of a human lung epithelial cell line (Calu-3). We have identified numerous transcription factors (JUN, ZBTB20, ATF3, HIVEP2 and EGR1) as well as select antiviral cytokine genes, namely IFNB1, IFNL1,2 and 3, IL-6 and CCL5, that are restricted at the post-transcriptional level by SARS-CoV-2 infection and discuss the impact this would have on the host response to infection. This early phase restriction of antiviral transcripts in the lungs may allow high viral load and consequent immune dysregulation typically seen in SARS-CoV-2 infection.

Multivariate genome-wide analysis of immunoglobulin G N-glycosylation identifies new loci pleiotropic with immune function

The N-glycosylation of immunoglobulin G (IgG) affects its structure and function. It has been demonstrated that IgG N-glycosylation patterns are inherited as complex quantitative traits. Genome-wide association studies identified loci harboring genes encoding enzymes directly involved in protein glycosylation as well as loci likely to be involved in regulation of glycosylation biochemical pathways. Many of these loci could be linked to immune functions and risk of inflammatory and autoimmune diseases. The aim of the present study was to discover and replicate new loci associated with IgG N-glycosylation and to investigate possible pleiotropic effects of these loci onto immune function and the risk of inflammatory and autoimmune diseases. We conducted a multivariate genome-wide association analysis of 23 IgG N-glycosylation traits measured in 8090 individuals of European ancestry. The discovery stage was followed up by replication in 3147 people and in silico functional analysis. Our study increased the total number of replicated loci from 22 to 29. For the discovered loci, we suggest a number of genes potentially involved in the control of IgG N-glycosylation. Among the new loci, two (near RNF168 and TNFRSF13B) were previously implicated in rare immune deficiencies and were associated with levels of circulating immunoglobulins. For one new locus (near AP5B1/OVOL1), we demonstrated a potential pleiotropic effect on the risk of asthma. Our findings underline an important link between IgG N-glycosylation and immune function and provide new clues to understanding their interplay.

Genome-wide interaction study reveals age-dependent determinants of responsiveness to inhaled corticosteroids in individuals with asthma

While genome-wide association studies have identified genes involved in differential treatment responses to inhaled corticosteroids (ICS) in asthma, few studies have evaluated the potential effects of age in this context. A significant proportion of asthmatics experience exacerbations (hospitalizations and emergency department visits) during ICS treatment. We evaluated the interaction of genetic variation and age on ICS response (measured by the occurrence of exacerbations) through a genome-wide interaction study (GWIS) of 1,321 adult and child asthmatic patients of European ancestry. We identified 107 genome-wide suggestive (P<10-05) age-by-genotype interactions, two of which also met genome-wide significance (P<5x10-08) (rs34631960 [OR 2.3±1.6-3.3] in thrombospondin type 1 domain-containing protein 4 (THSD4) and rs2328386 [OR 0.5±0.3-0.7] in human immunodeficiency virus type I enhancer binding protein 2 (HIVEP2)) by joint analysis of GWIS results from discovery and replication populations. In addition to THSD4 and HIVEP2, age-by-genotype interactions also prioritized genes previously identified as asthma candidate genes, including DPP10, HDAC9, TBXAS1, FBXL7, and GSDMB/ORMDL3, as pharmacogenomic loci as well. This study is the first to link these genes to a pharmacogenetic trait for asthma.

HIV-1 infection increases microRNAs that inhibit Dicer1, HRB and HIV-EP2, thereby reducing viral replication

HIV-1 is the causative agent of AIDS (Autoimmune Deficiency Syndrome). HIV-1 infection results in systemic CD4⁺ T cell depletion, thereby impairing cell-mediated immunity. MicroRNAs are short (~22 nucleotides long), endogenous single-stranded RNA molecules that regulate gene expression by binding to the 3' untranslated regions (3' UTR) of mRNA transcripts. The relation between HIV-1 infection and human miRNA expression profile has been previously investigated, and studies have shown that the virus can alter miRNA expression and vice versa. Here, we broaden the understanding of the HIV-1 infection process, and show that miRNA-186, 210 and 222 are up-regulated following HIV-1 infection of human Sup-T1 cells. As a result, the host miRNA target genes: Dicer1 (Double-Stranded RNA-Specific Endoribonuclease), HRB (HIV-1 Rev-binding protein) and HIV-EP2 (Human Immunodeficiency Virus Type I Enhancer Binding Protein 2), are down-regulated. Moreover, testing the miRNA-gene anti- correlation on the Jurkat and the HeLa-MAGI cell lines demonstrated the ability of the miRNAs to down-regulate viral expression as well. To conclude, we found that human miR-186, 210 and 222 directly regulate the human genes Dicer1, HRB and HIV-EP2, thus may be filling key roles during HIV-1 replication and miRNA biogenesis. This finding may contribute to the development of new therapeutic strategies.

Systems biology and the quest for correlates of protection to guide the development of an HIV vaccine

Over the last three decades, a myriad of data has been generated regarding HIV/SIV evolution, immune evasion, immune response, and pathogenesis. Much of this data can be integrated and potentially used to generate a successful vaccine. Although individual approaches have begun to shed light on mechanisms involved in vaccine-conferred protection from infection, true correlates of protection have not yet been identified. The systems biology approach helps unify datasets generated using different techniques and broaden our understanding of HIV immunopathogenesis. Moreover, systems biology is a tool that can provide correlates of protection, which can be targeted for the production of a successful HIV vaccine.

Loss-of-function variants in HIVEP2 are a cause of intellectual disability

Intellectual disability (ID) affects 2-3% of the population. In the past, many genetic causes of ID remained unidentified due to its vast heterogeneity. Recently, whole exome sequencing (WES) studies have shown that de novo variants underlie a significant portion of sporadic cases of ID. Applying WES to patients with ID or global developmental delay at different centers, we identified three individuals with distinct de novo variants in HIVEP2 (human immunodeficiency virus type I enhancer binding protein), which belongs to a family of zinc-finger-containing transcriptional proteins involved in growth and development. Two of the variants were nonsense changes, and one was a 1 bp deletion resulting in a premature stop codon that was reported previously without clinical detail. In silico prediction programs suggest loss-of-function in the mutated allele leading to haploinsufficiency as a putative mechanism in all three individuals. All three patients presented with moderate-to-severe ID, minimal structural brain anomalies, hypotonia, and mild dysmorphic features. Growth parameters were in the normal range except for borderline microcephaly at birth in one patient. Two of the patients exhibited behavioral anomalies including hyperactivity and aggression. Published functional data suggest a neurodevelopmental role for HIVEP2, and several of the genes regulated by HIVEP2 are implicated in brain development, for example, SSTR-2, c-Myc, and genes of the NF-κB pathway. In addition, HIVEP2-knockout mice exhibit several working memory deficits, increased anxiety, and hyperactivity. On the basis of the genotype-phenotype correlation and existing functional data, we propose HIVEP2 as a causative ID gene.

Identification and characterization of human MIBP1 gene in glioma cell differentiation

Malignant gliomas are the most common and lethal intracranial tumors; differentiation therapy is a promising candidate for their treatment. In order to reveal the mechanisms related to glioma differentiation, after confirming that differentiation was induced by sodium phenylbutyrate in SHG-44 human glioma cells, RNA arbitrary primer differential display was used to screen differentially expressed genes. One gene was found to be upregulated by differential display, and this was also confirmed by reverse northern blot and quantitative real-time PCR analysis. After it was cloned and sequenced, the 505-bp fragment was identified as the MIBP1 (c-myc intron-binding protein 1) gene, also named Hivep2/MBP-2/Schnurri-2. Quantitative real-time PCR analysis of 30 human tissue samples revealed that the expression of MIBP1 tended to decrease with increasing WHO grade and was significantly depressed in the high malignancy gliomas group (WHO grade IV). We cloned and sequenced the MIBP1 gene, which was accepted by GenBank as number DQ231041. Finally, transfection of MIBP1 in a reverse transcription vector into glioma cells inhibited cell growth, induced differentiation, and blocked the cell cycle. Here, we identify and describe the structure and function of a differentiation-related gene, human MIBP1, in human glioma.

Murine Schnurri-2 controls natural killer cell function and lymphoma development

Schnurri (Shn)-2 is a large zinc finger-containing protein implicated in cell growth, signal transduction and lymphocyte development. Here, we report that Shn-2-deficient (Shn-2(-/-)) mice develop CD3-positive lymphoma spontaneously. In Shn-2(-/-) mice, we observed decreased cytotoxicity of natural killer (NK) cells accompanied by decreased expression of perforin and granzyme-B. In addition, phosphorylation of signal transducer and activator of transcription (STAT) 5 was reduced in Shn-2(-/-) NK cells, while phosphorylation of STAT3 and protein expression of nuclear factor-κB p65 subunit were enhanced in Shn-2(-/-) NK cells. Moreover, cell-surface expression of activation molecules such as CD27, CD69 and CD122 were decreased on Shn-2(-/-) NK cells. Thus, Shn-2 is considered to play an important role in the activation and function of NK cells and the development of T cell lymphoma in vivo.

Role of T cell-nuclear factor κB in transplantation

Nuclear factor (NF) κB is a pleiotropic transcription factor that is ubiquitously expressed. After transplantation of solid organs, NF-κB in the graft is activated within a few hours as a consequence of ischemia/reperfusion and then again after a few days in intragraft infiltrating cells during the process of acute allograft rejection. In the present article, we review the components of the NF-κB pathway, their mechanisms of activation, and their role in T cell and antigen-presenting cell activation and differentiation and in solid organ allograft rejection. Targeted inhibition of NF-κB in selected cell types may promote graft survival with fewer adverse effects compared with global immunosuppressive therapies.

Schnurri-2 deficiency counteracts against bone loss induced by ovariectomy

Schnurri (Shn)-2 is a transcriptional modulator of bone formation and bone resorption and its deficiency causes low turnover state with higher cancellous bone mass due to the defects in osteoclasts that exceeds the defects in osteoblasts in mice. We addressed whether such low turnover of bone remodeling in Shn2 deficiency may be modulated in the absence of estrogen that induces high turnover state in vivo. Ovariectomy reduced bone mass in wild type compared to sham operated control mice and such reduction in bone mass was also observed in Shn2 deficient mice. However, due to the high levels of basal bone mass in Shn2 deficient mice, the bone mass levels after ovariectomy were still comparable to sham operated wild-type mice. Analysis indicated that estrogen depletion increased bone resorption at similar levels in wild type and Shn2 deficient mice though the basal levels of osteoclast number was slightly lower in Shn2-deficient mice. In contrast, basal levels of bone marrow cell mineralization in cultures were low in Shn2-deficeint mice while estrogen depletion increased the mineralization levels to those that were comparable to sham wild type. This indicates that Shn2-deficient mice maintain bone mass at the levels comparable to wild-type sham mice even after ovariectomy-induced bone loss and this correlates with the high levels of mineralization activity in bone marrow cells after ovariectomy.