Iranian journal of immunology
Volume:19 Issue: 3, Summer 2022

Impaired renal function is considered as a significant risk factor for cardiovascular events in chronic kidney disease patients. Several immunosuppressive drugs are used in these patients, which necessitates to minimize the drug-related side effects by employing alternative strategies.

This study aimed to evaluate prospectively the influence of low dose ATG induction therapy with two different protocols (Sirolimus versus Mycophenolate mofetil) on the expression of functional markers (LAG-3, CD39, and intracellular CTLA-4) on conventional Tregs in renal recipients.

Thirty-eight renal transplant recipients were enrolled in this study. The patients were randomly assigned into two groups, including TMP: Tacrolimus (Tac), Mycophenolate mofetil (MMF), and Prednisolone (n=23); and TSP: Tac, Sirolimus (SRL), and Prednisolone (n=15). The frequency of LAG-3, CD39, and intracellular CTLA-4 on circulating Tregs was analyzed by flow cytometry before and after transplantation.

Analysis of the flow cytometry data showed that the frequency of CD4+CD25+FOXP3+ Tregs increased 4 months post-transplantation compared to pre-transplantation in both groups, although this increase was only significant in TMP group. In TMP treated patients, the frequency of LAG-3+ Tregs and CD39+ Tregs increased, whereas the frequency of intracellular CTLA-4+ Tregs decreased 4 months post-transplantation. In TSP group, while the frequency of CD39+ Tregs increased, the frequency of CTLA-4+ Tregs decreased in post-transplantation compared to pre-transplantation.

it seems that both treatment regimen protocols with a low dose ATG induction therapy may be clinically applicable in kidney transplant recipients.

Sepsis is a serious condition with a high mortality rate, and septic patients often have organ dysfunction, low tissue perfusion and hypoxia, lactic acidosis, oliguria, or functional brain changes. To observe the number and the function of Vδ1T cells in peripheral blood of septic patients, to analyze the clinical significance of detecting Vδ1T cells, and to clarify the correlation of their presence with the prognosis of sepsis. The basic data of the septic patients were recorded at admission. The immunosuppressive function–related molecules on the surface of Vδ1T cells were detected, and the immunosuppressive function of Vδ1T cells was also evaluated. Compared with the healthy controls, the proportion of Vδ1T cells in the blood of septic patients significantly decreased (P<0.01). The proportion of Vδ1T cells in septic patients correlated with the patients’ condition (P<0.05). The expression of glucocorticoid-induced tumor necrosis factor receptor (GITR), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), and T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) on the surface of Vδ1T cells in the blood of septic patients significantly increased (P<0.01). The increase of Vδ1T cells in septic patients had inhibitory effects on T cell proliferation and interferon (IFN)-γ secretion. These findings implied that the immunosuppression of Vδ1Tcells in the peripheral blood of septic patients was significantly higher than that of the healthy controls (P<0.01). Changes in Vδ1T cells in septic patients were closely related to the patient’s condition and prognosis.

Background :

Dysregulation of the balance between different T cell populations is believed to be an important basis for asthma.

Objective:

 To observe the changes in γδT subtypes in transgenic asthmatic mice after aerosol inhalation of Mycobacterium vaccae, and to further investigate the mechanism of M. vaccae in asthmatic mice and its relationship with γδT cells.

Methods:

 TCR-β-/- mice were exposed to atomized normal saline or M. vaccae for 5 days and the γδT cells from the lung tissues were isolated. Changes in γδT17 and γδTreg populations were detected. Asthma was induced in BALB/c mice using ovalbumin, which was then transplanted with control or M. vaccae-primed γδT cells. First we analyzed the content of γδT cells that secrete IL-17 (IL-17 γδT cells) and Foxp3+ γδT cells in lung tissues and then measured the content of IL-17 in the bronchoalveolar lavage fluid (BALF) by ELISA.

Results:

 Exposure to M. vaccae increased and decreased the relative proportions of Foxp3+ γδT cells and IL-17+ γδT cells, respectively, thereby decreasing airway reactivity and inflammation levels in asthmatic mice, and significantly decreasing IL-17 levels in BALF. Furthermore, mice treated with these primed T cells showed a decrease in IL-17+ γδT cells, and a concomitant increase in Foxp3+ γδT cells in their lung tissues. Furthermore, adoptive transfer of M. vaccae-primed γδT cells decreased GATA3 and NICD and increased T-bet in lung.

Conclusions:

 The M. vaccae-primed γδT cells alleviated the symptoms of asthma by reversing Th2 polarization in the lungs and inhibiting the Notch/GATA3 pathway.

Natural killer (NK) cells are dichotomously involved in chronic hepatitis B (CHB) infection as principal members of innate immunity. An effective treatment should enhance the antiviral potentials of NK cells and not their immunomodulatory roles. TIM-3 (T-cell immunoglobulin and mucin-containing domain) is a molecule with an essential role in controlling immune tolerance. TIM-3 demonstrated the highest expression among NK cells of patients with chronic liver disorders. Statins have been reported to attenuate the levels of TIM-3 on NK cells. To investigate the frequencies of NK cells, NKT cells, and TIM-3+ population in patients with CHB upon rosuvastatin (RSV) intervention. Thirty confirmed patients with CHB were randomly assigned into two groups of 15 (receiving 20 mg of RSV or placebo per day) for 12 weeks. We evaluated the percentages of TIM-3+ cells by staining the peripheral blood mononuclear cells (PBMCs) with CD3, CD16, and CD56 markers using flow cytometry. Our findings indicated that RSV administration could increase CD3- CD56+ NK cells (P>0.05) and CD3+ CD16+ CD56+ NKT cells (P<0.05). RSV intervention could reduce the percentages of TIM-3+ cells among NK cells (P<0.01) and NKT cells (P> 0.05) of patients with CHB compared with the placebo group. The increased population of NK and NKT cells and the effective reduction of TIM-3+ cells among patients with CHB delineated that rosuvastatin could be proposed as an appropriate modulator of innate immune response (regarding NK and NKT cells) in favor of enhancing their antiviral activities.

The negative feedback circuit NIK-SIN could inhibit the systemic inflammation and protect mouse from endotoxic shock. However, the physiological significance of NIK-SIX feedback circuit in the maintenance of intestinal immune homeostasis and prevention of early-onset spontaneous colitis is not known. To explore the role of NIK-SIX axis in the maintenance of intestinal immune homeostasis. The conditional knockout of NIK encoding gene, Map3k14, in the Cd11c+ dendritic cells were generated by crossing Map3k14-flox mice with Cd11c-Cre mice. DSS was used for colitis models. The expression of cytokines in the intestinal immune cells, isolated from Map3k14-cKO mice were detected by qPCR. The siRNA molecules were used for the silencing of SIN-proteins. Then luciferase assays and chromatin immunoprecipitation combined with qPCR were applied for mechanism investigations. The expression of SIX1 and SIX2 protein in BMDMs from WT were significantly lower than in the Map3k14-cKO mice. In vitro, the NIK-/- human-derived circulating monocytes also failed to express SIX-proteins under the stimulation of non-canonical NF-κB agonists. The expression of cytokines was significantly decreased in human circulating monocytes with overexpression SIN-proteins. The expression of cytokines in macrophages, DCs and T cells isolated from Map3k14-cKO mice were significantly increased in the DSS-induced models. Higher expression of cytokines was observed in the SIN1-/- and SIN2-/- cells including human circulating monocytes, mouse-derived BMDMs, intestinal macrophages and DCs. SIN-proteins directly bound the promoter region of inflammatory genes. NIK-SIX axis down-regulated inflammatory gene expression and plays a pivotal role in the maintenance of intestinal immune homeostasis.

Human polyclonal plasma-derived hepatitis B immunoglobulin (HBIG) is currently used for immunoprophylaxis of HBV infection. The development of virus-neutralizing monoclonal antibodies (MAbs) requires the use of optimized cell culture systems supporting HBV infection.

This study aims to optimize the hepatitis B virus infectivity of NTCP-reconstituted HepG2 (HepG2-NTCP) cells to establish an efficient system to evaluate the HBV-neutralizing effect of anti-HBs MAbs.

Serum-derived HBV (sHBV) and cell culture-derived HBV (ccHBV) were simultaneously used for the optimization of HBV infection in HepG2-NTCP cells by applying different modifications.

Our results for the first time showed that in addition to human serum, monkey serum could significantly improve ccHBV infection, while fetal and adult bovine serum as well as duck and sheep serum did not have a promotive effect. In addition, sHBV and ccHBV infectivity are largely similar except that adding 5% of PEG, which is commonly used to improve in vitro infection of ccHBV, significantly reduced sHBV infection. We showed that a combination of spinoculation, trypsinization, and also adding human or monkey serum to HBV inoculum could significantly improve the permissivity of HepG2-NTCP cells to HBV infection compared with individual strategies. All anti-HBs MAbs were able to successfully neutralize both ccHBV and sHBV infection in our optimized in vitro system.

Our study suggests different strategies for improving ccHBV and sHBV infection in HepG2-NTCP cells. This cell culture-based system allows assessment of HBV neutralizing MAbs and may also prove to be valuable for the analysis of other HBV neutralizing therapeutics.

Periodontal diseases originate from a group of oral inflammatory infections initiated by oral pathogens. Among these pathogens, Gram-negative bacteria such as p. gingivalis play a major role in chronic periodontitis. P. gingivalis harbours lipopolysaccharide (LPS) which enables it to attach to TLR2. Evaluating the effects of P. gingivalis and E. coli LPS on the gene expression of TLRs and inflammatory cytokines in human dental pulp stem cells (hDPSCs). We evaluated the expression level of TLR2, TLR4, IL-6, IL-10, and 1L-18 in hDPSCs treated with 1μg/mL of P. gingivalis lipopolysaccharide and E. coli LPS at three different exposure times using Real-time RT-PCR. The test group treated with P. gingivalis LPS showed a high level of TLR4 expression in 24 hours exposure period and the lowest expression in 48 hours of exposure time. In the case of IL-10, the lowest expression was in the 24 hours exposure period. Although in the E.coli LPS treated group, IL-10 showed the highest expression in 24 and lowest in 48 hours exposure period. Moreover, IL-18 in P. gingivalis LPS treated group showed a significant difference between 6, 24, and 48-time periods of exposure, but not in the E. coli LPS treated group. Both types of LPS stimulate inflammation through TLR4 expression. P. gingivalis LPS performs more potentially than E. coli in terms of stimulating inflammation at the first 24 hours of exposure. Nevertheless, our study confirmed that increasing P. gingivalis and/or the E.coli LPS exposure time, despite acting as an inflammatory stimulator, apparently showed anti-inflammatory properties.

Coronavirus disease 2019 (COVID-19) is an emergent viral disease in which the host inflammatory response modulates the clinical outcome. Severe outcomes are associated with an exacerbation of inflammation in which chemokines play an important role as the attractants of immune cells to the tissues. To evaluate the relationship of the chemokines IL-8, RANTES, MIG, MCP-1, and IP-10 with COVID-19 severity and outcomes in Mexican patients. We analyzed the serum levels of IL-8, RANTES, MIG, MCP-1 and IP-10 in 148 COVID-19 hospitalized patients classified as mild (n=20), severe (n=61), and critical (n=67), as well as in healthy individuals (n=10), by flow cytometry bead array assay. Chemokine levels were higher in patients than in the healthy individuals, but only MIG, MCP-1, and IP-10 increased according to the disease severity, showing the highest levels in the critical group. MIG, MCP-1, and IP-10 levels were also higher in COVID-19 patients with comorbidities such as renal disease, type 2 diabetes, and hypertension. Moreover, elevated MIG levels seem to be related to organic failure/shock, and an increased risk of death. Our results suggest that the increased levels of MCP-1, IP-10, and especially MIG might be useful in predicting severe COVID-19 outcomes and could be promising therapeutic targets.

 Vaccines are the most effective way to prevent Coronavirus 2 severe acute respiratory syndrome (SARS-CoV-2). To compare the antibody response of healthy individuals vaccinated with either the AstraZeneca (ChAdOx1 nCoV-19) or the Sinopharm (BBIBP-CorV) vaccine, in those who had no prior infection with SARS-CoV-2. Thirty seven participants were included, of which 17 were administered the AstraZeneca (ChAdOx1 nCoV-19) vaccine, while 20 were given the Sinopharm (BBIBP-CorV) vaccine. SARS-CoV-2 neutralizing antibody and anti-receptor-binding domain (RBD) IgG levels were checked 4 weeks after giving the first and the second dose of either vaccine using the enzyme-linked immunosorbent assay (ELISA) technique. The AstraZeneca (ChAdOx1 nCoV-19) vaccine exhibited a higher levels of anti-(RBD) IgG compared with the Sinopharm (BBIBP-CorV) in both the first (14.51 μg/ml vs. 1.160 μg/ml) and the second (46.68 μg/ml vs. 11.43 μg/ml) doses. About neutralizing Abs, the titer of the antibody was higher in the AstraZeneca (ChAdOx1 nCoV-19) recipients than in the Sinopharm (BBIBP-CorV) subjects after the first (7.77 μg/ml vs. 1.79 μg/ml, p < 0.0001) and the second dose (10. 36 μg/ml vs. 4.88 μg/ml, p < 0.0001). Recipients vaccinated with two doses of the AstraZeneca (ChAdOx1 nCoV-19) had superior quantitative antibody levels than Sinopharm (BBIBP-CorV)-vaccinated subjects. These data suggest that a booster dose may be needed for the Sinopharm (BBIBP-CorV) recipients, to control the COVID-19 pandemic.

Pregnant women with coronavirus disease 2019 (COVID-19) have a higher risk of morbidity and mortality compared with the general population. Possible pathways are: I) in patients with COVID-19, cytokine storm defined as the excess release of pro-inflammatory cytokines such as interleukin 1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) has been associated with morbidities and an even higher rate of mortality. II) Labor, despite being a term/preterm, has an inflammatory nature, although, inflammation is more prominent in preterm delivery. During labor, different pro-inflammatory cytokines such as IL-1β, IL-6, and TNF-α are involved which as mentioned, all are crucial role players in the cytokine storm. III) Tissue injury, and during labor, (especially cesarean section) is shown to cause inflammation via pro-inflammatory cytokines release including those involved in the cytokine storm through the activation of nuclear factor κB (NFκB). IV) post-partum hemorrhage with a notable amount of blood loss which can cause significant hypoxemia. In this condition, hypoxia-inducible factor 1α which has a cross-talk with NFκB, leads to the expression of IL-1β, IL-6, and TNF-α as both angiogenic and pro-inflammatory factors. Considering all the mentioned issues and pathways, we suggest that clinicians be careful about the escalation of the inflammatory status in their pregnant COVID-19 patients during/following labor.

Recently in a review article by Mansourabadi et al. published in the Iranian Journal of Immunology, the authors described the serological and molecular tests for COVID-19 (1). The mentioned review considered helicase (Hel) as a structural protein of SARS-CoV-2 (1). However, based on evidence, the genome of novel coronavirus is approximately 30kb in length and encodes only four structural proteins, including spike (S), envelope (E), membrane (M), and nucleoprotein (N) (2, 3), although helicase (NSP13) as a nonstructural protein such as RNA-dependent RNA polymerases (NSP12) encoded by the ORF region and is involved in the replication of the virus (3). In addition, authors reported that hemagglutinin esterase could be used as a favorite target for SARS-CoV-2 Real-time PCR (1); however, scientific evidence shows that SARS-CoV-2 as a betacoronavirus lineage B like SARS-CoV lacks hemagglutinin esterase (4-6); thus this protein cannot be a target for detection of SARS-CoV-2.