Iranian journal of immunology
Volume:21 Issue: 1, Winter 2024

Since the outbreak of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), several vaccine candidates have been developed within a short period of time. Although the potency of these vaccines was evaluated individually, their comparative potency was not comprehensively evaluated.

To compare the immunogenicity and neutralization efficacy of four approved COVID-19 vaccines in Iran, including: PastoCovac Plus, Sinopharm, SpikoGen, and Noora in BALB/c mice.

Different groups of female BALB/c mice were vaccinated with three doses of each vaccine. The serum levels of antibodies against the viral receptor binding domain (anti-RBD) and spike (anti-spike) protein as well as the vaccine formulation (anti-vaccine) were evaluated using enzyme-linked immunosorbent assay (ELISA). The neutralization efficacy of these four vaccines was assessed through four neutralization assays: conventional virus neutralization test (cVNT), pseudotype virus neutralization test (pVNT), surrogate virus neutralization test (sVNT), and inhibition flow cytometry.

All four vaccines induced seroconversion in vaccinated animals. All vaccines successfully induced high levels of anti-vaccine antibody; however, PastoCovac Plus and Sinopharm vaccines induced significantly higher levels of anti-RBD antibody titer compared to Noora and SpikoGen. Moreover, the results of the antibody response were corroborated by the virus neutralization tests, which revealed very weak neutralization potency by Noora and SpikoGen in all tests.

Our results indicate significant immunogenicity and neutralization efficacy induced by PastoCovac Plus and Sinopharm, but not by Noora and SpikoGen. This suggests the need for additional comparative assessment of the potency and efficacy of these four vaccines in vaccinated subjects.

Immunotherapies targeting peripheral natural killer (pbNK) cells in unexplained recurrent miscarriage (uRM) remain controversial. We hypothesized that the change in pbNK cell count might be a result of innate immune responses rather than a cause. To explore whether the pbNK count is significantly different in women testing positive than those testing negative for commonly studied autoimmune markers. Peripheral blood samples were collected from 302 eligible patients with uRM for the antinuclear antibody (ANA) testing determined by the enzyme-linked immunosorbent assay (ELISA), anti-thyroid peroxidase antibody (TPO-Ab) testing and anti-thyroglobulin antibody (Tg-Ab) testing determined by the chemiluminescent immunoassay, and pbNK cell testing determined by flow cytometry. The patients were divided into two groups according to the pbNK normal range, and the comparative analysis entailed an examination of the prevalence rates of autoantibodies within the high pbNK group and the normal pbNK group, followed by a comprehensive investigation into the potential correlations between autoantibodies and pbNK cells. There was a positive association between TPO-Ab positivity and high pbNK cells (p=0.016, OR=5.097, 95% CI 1.356–19.159), while there was a negative association between ANA positivity and high pbNK cells (p=0.013, OR=0.293, 95% CI 0.111-0.773). TPO-Ab-positive patients had a higher pbNK cell count compared with TPO-Ab-negative patients, while ANA-positive patients had a lower pbNK cell count compared with ANA-negative patients. The change in pbNK cell count may be a consequence of immune responses, and there should be careful consideration in applying it as an immunotherapeutic index.

Endometriosis is a medical condition that can cause infertility in women. Women with endometriosis experience a decrease in NK cell cytotoxic activity against endometrial cells, ultimately contributing to the spread of these cells. To assess the frequency of NK cells and the expression of the NKP46 receptor in endometrial tissue from patients with endometriosis using immunohistochemistry. 30 endometrial tissue specimens were collected from three groups of cases with mild (n=11), moderate (n=10), and severe endometriosis (n=9), respectively. Additionally, 20 normal endometrial tissue specimens were collected as the control group. Immunohistochemical staining was carried out using specific human monoclonal antibodies against CD56 and NKP46 molecules. Cases with severe endometriosis had a significantly higher number of CD56+ uterine NK cells (26.19±2.50) compared to fertile women (15.02±0.622) and women with mild to moderate endometriosis (p<0.001). However, there was no significant difference between the mild to moderate patients compared with the healthy women (p>0.05). Endometrial NKp46 expression was lower in women with severe endometriosis (0.447±0.0829) compared to fertile women (0.987±0.115, p=0.03). The NKp46+/CD56+ cell ratio was also lower in women with severe endometriosis (0.019±0.003) compared to fertile women (0.072±0.011, p=0.01). Women with severe endometriosis demonstrated an increased rate of infiltrated uterine NK cells and a significant decrease in NKP46 expression compared to fertile women. Therefore, NK cells and the NKp46 receptor may be involved in the development of endometriosis.

The imbalance between M1 and M2 macrophage activation is closely associated with the pathogenesis of inflammatory bowel diseases (IBDs). Sulforaphane (SFN) plays an important role in the treatment of inflammatory diseases. To investigate the effect of SFN on macrophage polarization and its underlying regulatory mechanism. Mouse bone marrow-derived macrophages (BMDMs) were treated with SFN and an Nrf2 inhibitor, Brusatol. M1 macrophages were induced by LPS and IFN-γ stimulation, whereas M2 macrophages were induced by stimulation with IL-4 and IL-13. LPS-stimulated BMDMs were co-cultured with Caco-2 cells. Flow cytometry, qRT-PCR, and Western blot were performed to assess macrophage polarization. Cell function was assessed using CCK8 assay, transepithelial electrical resistance (TEER) assay, and biochemical analysis. Higher concentrations of SFN resulted in better intervention effects, with an optimal concentration of 10 μM. SFN decreased the levels of IL-12, IL-6, and TNF-α, as well as the percentages of CD16/32 in M1 BMDMs. At the same time, SFN increased the levels of YM1, Fizz1, and Arg1 as well as the percentages of CD206+ cells in M2 BMDMs. In addition, SFN enhanced the accumulation of Nrf2, NQO1, and HO-1 in M1 BMDMs, and the downregulation of Nrf2 reversed the regulatory effect of SFN on M1/M2 macrophages. LPS-stimulated BMDMs induced Caco-2 cell damage, which was partially alleviated by SFN. Our findings indicate that SFN may act as an Nrf2 agonist to regulate macrophage polarization from M1 to M2. Furthermore, SFN may represent a potential protective ingredient against IBD.

Neutrophilic asthma is characterized by the predominant infiltration of neutrophils in airway inflammation. To explore the therapeutic potential of an antibody against the inducible T cell co-stimulator ligand (ICOSL) in a mouse model of neutrophilic asthma. Female BALB/c mice were randomly assigned to different groups. They were then injected with ovalbumin (OVA)/lipopolysaccharides (LPS) to induce neutrophilic asthma. The mice were then treated with either anti-ICOSL (the I group), control IgG (the G group), or no treatment (the N group). Additionally, a control group of mice received vehicle PBS and was labeled as the C group (n=6 per group). One day after the last allergen exposure, cytokine levels were measured in plasma and bronchoalveolar lavage fluid (BALF) using ELISA. After analyzing and categorizing BALF cells, the lung tissues were examined histologically and immunohistochemically. Administering anti-ICOSL resulted in a significant decrease in the total number of inflammatory infiltrates and neutrophils found in BALF. Moreover, it led to a decrease in the levels of interleukin (IL)-6, IL-13, and IL-17 in both BALF and plasma. Additionally, there was an increase in IFN-γ levels in the BALF of asthmatic mice (p<0.05 for all). Treatment with anti-ICOSL also reduced lung interstitial inflammation, mucus secretion, and ICOSL expression in asthmatic mice. The treatment of anti-ICOSL effectively improved lung interstitial inflammation and mucus secretion in mice with neutrophilic asthma by restoring the balance of Th1/Th2/Th17 responses. These findings indicate that blocking the ICOS/ICOSL signaling could be an effective way to manage neutrophilic asthma.

Tumor-infiltrating lymphocytes (TILs) and brain stromal cells produce immunosuppressive cytokines, contributing to an immunosuppressive tumor microenvironment (TME). Interleukin-38 (IL-38) is a novel anti-inflammatory cytokine and a natural modulator of the innate and adaptive immune system. However, its biological roles in brain tumors are not well defined.

To assess the serum levels of IL-38 and the percentages of TILs in the tumor tissues of patients with primary brain tumors and to determine their associations with the pathological features of the disease.

IL-38 was evaluated in sera using the enzyme-linked immunosorbent assay (ELISA). Hematoxylin and eosin (H&E)-stained sections were scored to determine the percentages of TILs in four different areas: the invasive margin, central tumor, perivascular and perinecrotic areas.

IL-38 serum levels were significantly higher in low- and high-grade tumors than in healthy individuals, meanwhile, its levels remained consistent between these two grades. Although no significant difference was found in IL-38 serum levels between different histological subtypes of brain tumors, its levels were significantly higher in intra-axial brain tumors than in extra-axial ones. Additionally, a significant positive correlation was observed between serum levels of IL-38 and tumor size in patients with low-grade tumors. TILs were detected in at least one of the four examined areas; however, no statistically significant correlation was found between IL-38 levels and TILs.

Our data may suggest a connection between IL-38 and immune suppression and tumor progression in primary brain tumors. Further investigation is needed to uncover the role of IL-38 in the brain tumor microenvironment.

Pulmonary neutrophils may play a crucial role in the development of bronchiolitis obliterans (BO) following measles virus infection. IL-27 could potentially have a negative regulatory effect on the release of reactive oxygen species and cytotoxic granules in neutrophils. To investigate the levels of IL-27 in the bronchoalveolar lavage fluid (BALF) of children with post-infectious bronchiolitis obliterans (PIBO) and analyze the relationship between IL-27 levels and neutrophil proportions. A total of 24 children with PIBO were recruited for the experimental group, while 23 children with bronchial foreign bodies were included in the control group. Bronchoscopic alveolar lavage was performed in both groups. The levels of IL-27 in BALF were measured using enzyme-linked immunosorbent assay (ELISA). The proportions of neutrophils in BALF were determined by smear staining. The relationship between the levels of IL-27 in BALF and the neutrophil proportions was analyzed by the Pearson test. The levels of IL-27 in BALF were significantly lower in children with PIBO compared to children with bronchial foreign bodies (p<0.05). Additionally, the proportions of neutrophils in BALF were significantly higher in children with PIBO compared to children with bronchial foreign bodies (p<0.05). The levels of IL-27 were negatively correlated with the neutrophil proportions in BALF in children with PIBO (p<0.05), but not in children with bronchial foreign bodies (p>0.05). The present study suggests that a decrease in IL-27 may be associated with an increase in neutrophils in BALF and may contribute to the pathogenesis of PIBO.

Human adenovirus (HAdV) is an enveloped icosahedral DNA virus. HAdV infection can lead to immune system damage, resulting in decreased numbers and compromised function of T cells and B cells. It can also cause an imbalanced Th1/Th2 ratio and dysregulation of pro-inflammatory and anti-inflammatory cytokines. To investigate the serum levels of interleukin (IL)-13 and IL-17A in children with HAdV pneumonia. Pediatric patients diagnosed with HAdV pneumonia were divided into a non-severe group or a severe group based on the severity of their condition. Patients in the severe group were further classified into good and poor prognosis subgroups. We collected 2-2.5 mL of venous blood from each patient, which was then centrifuged. Using an ELISA detection kit, we determined the concentrations of IL-13 and IL-17A. Patients with a severe condition exhibited significantly higher serum concentrations of IL-13 and IL-17A than the non-severe cases. Out of 50 severe cases, 32 had good prognoses, while 18 cases showed poor prognoses. Patients with poor prognoses showed significantly higher serum concentrations of IL-13 compared to those with good prognoses. Serum concentrations of IL-13 and IL-17A are potential diagnostic markers for pediatric patients with severe HAdV pneumonia. Additionally, they demonstrate good predictive value for a poor prognosis in severe pneumonia cases.

Understanding the effects of epigenetic factors on the pathogenesis of rheumatoid arthritis (RA) is important for the early diagnosis and therapeutic intervention of this disease. MicroRNA-150 (miR-150) exerts an important influence on the development and function of lymphocytes. However, the role of miR-150 in the pathogenesis of RA remains unclear. To explore the role of miR-150 in the pathogenesis of RA and the related immune mechanism. In this study, we used miR-150 knock-out (miR-150KO) and created animal models of RA. Flow cytometry, immunohistochemistry, and real-time RT-PCR were employed to assess the frequency of T cell subsets and cytokines expression. Compared to wild-type (WT) mice, the onset of RA was postponed and the incidence of RA was reduced in miR-150KO mice. The expression of IL-4 and IFN-γ significantly increased while the expression of IL-17 decreased significantly in NKT and CD4+ T cells of KO mice compared to that of WT mice after RA induction. In addition, the expression of IL-4 and IFN-γ increased while the expression of IL-17 decreased significantly in the joint tissues of KO mice compared to that of WT mice. Furthermore, the mRNA expression of TNF-α and IL-17 decreased significantly in the synovial fluid cells of KO mice compared to that of the WT mice after RA induction. MiR-150 deficiency decreases the expression of IL-17 in T cells and joint tissues, and alleviates the occurrence and progression of RA in mice.

Dear Editor I am writing in response to the recently published study titled "Antibody Production after COVID-19 Vaccination in Patients with Inborn Errors of Immunity" (1). The article offers essential insights into the immune response engendered by COVID-19 vaccines in a vulnerable cohort. To build upon this seminal work and deepen our understanding, I offer the following brief suggestions for future research endeavours:Conduct longitudinal studies to track the long-term vaccine efficacy and the potential need for booster vaccinations in patients with inborn errors of immunity (IEI) (2). Utilize larger and more diverse patient populations for robustness in data and to better generalize findings across the spectrum of IEI conditions (3). Compare immune responses to different COVID-19 vaccine types within the IEI population to inform vaccine strategy optimizations (4). Thank you for your consideration of these suggestions, and I commend your journal for addressing this critical aspect of the pandemic's response. References: Nourizadeh M, Feizabadi E, Mirmoghtadaei M, Mohammadi A, Fazlollahi MR, Moradi L, et al. Antibody Production after COVID-19 Vaccination in Patients with Inborn Errors of Immunity. Iranian Journal of Immunology [Internet]. 2023 Dec 1;20(4):400–9 Tallantyre EC, Vickaryous N, Anderson V, Asardag AN, Baker D, Bestwick J, et al. COVID ‐19 Vaccine Response in People with Multiple Sclerosis. Annals of Neurology. 2021 Nov 17;91(1):89–100. Mohamed Khosroshahi L, Rokni M, Mokhtari T, Noorbakhsh F. Immunology, immunopathogenesis and immunotherapeutics of COVID-19; an overview. International Immunopharmacology [Internet]. 2021 Apr 1;93:107364. Liao SY, Gerber AN, Pearlanne Zelarney, Make B, Wechsler ME. SARS-CoV-2 mRNA Vaccine Antibody Response in Patients with Asthma Receiving Biologic Therapy: A Real-World Analysis. American Journal of Respiratory and Critical Care Medicine. 2022 Sep 1;206(5):644–8   Author’s response Dear Editor As the corresponding author of the above-mentioned manuscript, I would like to thank the author(s) of this letter for their interest in our paper and valuable comments. It is a great suggestion to track the long-term vaccine efficacy and conduct longitudinal evaluations, especially with a larger number of samples. Additionally, comparing different types of COVID-19 vaccines would be very thoughtful. However, the pandemic has ended, and alternative sampling at different time points, preferably close to the time of vaccination, is not practicable currently. Therefore, we may have missed the golden time to evaluate humoral immunity, but it could still be assessed with more precise molecular techniques not currently available in our center, such as Omics profiling of patients and RNA sequencing.