Iranian Journal of Allergy, Asthma and Immunology
Volume:19 Issue: 5, Oct 2020

The new coronavirus, known as “SARS-CoV-2”; is the cause of one of the most prevalent infectious viral diseases that was recently announced pandemic by the world health organization. Ongoing research in the fields of prevention, management, and therapy establishes a functional scaffold for clinics during the time of crisis. To obtain this goal, it is necessary that all pathophysiologic aspects of COVID-19 from infection to predisposing backgrounds of infection be identified, so that all the ambiguities of researchers regarding transmission mechanisms, variable clinical manifestation, and therapeutic response can be solved. Here, we firstly discuss about the homology screening between nCoV-2019 and beta-coronavirus family using phylogenetic analyses. Secondly, we analyzed the viral motifs to show that viral entry into the host cells requires a primary activation step performed by FURIN and FURIN-like-mediated enzymatic cleavage on the structural glycoprotein. The cleavage increases viral performance by 1000 folds. We then present a comprehensive view on host cells and the significance of gene variants affecting activation enzymes, supportive entry, and spread mechanisms in humans including renin-angiotensin-aldosterone system (RAAS) a pathway results in certain phenotypes or exacerbate infection-related phenotypes in different organs, hence causes variable clinical manifestations. This is followed by discussing about the importance of personalized medicine in nCoV-2019 exposure. Moreover, chemical drugs prescribed for individuals affected with COVID-19, as well as genes involved in drug transport and metabolisms are reviewed as a prelude to drug response. Finally, we suggest some therapeutic approaches developed based on new methods and technology such as anti-sense therapy and antibodies.

The emergence of a highly pathogenic virus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) accounts for severe pneumonia throughout the world. More than 7 million world population have been infected with SARS-CoV-2, and the number of deaths is increasing every day. This study aimed to evaluate the frequency of SARS-CoV-2 in hospitalized patients with an acute respiratory infection (ARI). During an outbreak of the SARS-CoV-2, the nasopharyngeal and oropharyngeal swabs were collected from 909 hospitalized patients with severe pneumonia, including 517 (56.9%) males and 392 (43.1%) females. All the collected samples were from different cities of Khuzestan province from 19 February to- 27 March 2020. The RNA was extracted from samples and subjected to real-time polymerase chain reaction (PCR) tests for the detection of the SARS-CoV-2. Simultaneously, the computerized tomography (CT) scan was tested for the presence of ground-glass opacity in the lung among the patients. Of the total number of 909 specimens, 328 (36.08%) cases, including 185 (20.35%) females and 143 (15.73%) males, were positive for the SARS-CoV-2 while, 581 (63.9%) cases, including 374 (41.14%) males and 207 (22.77%) were negative for the SARS-CoV-2 by real-time PCR (p=0.001).Four hundred sixteen (45.76%) cases were positive for ground-glass opacity in the lung by CT scan, while 328/909 (36.08%) trials proved positive for SARS-CoV-2 by the real-time PCR (p=0.003).  In this study, 36.08% of patients were positive for SARS-CoV-2. Although the results of positive cases by CT scan showed higher than real-time PCR, screening the SARS-COV-2 with a real-time PCR method is the first line of choice.

This study aims to investigate the role of prenatal diagnosis (PND) in Iranian couples with a previous history of primary immunodeficiency disorders (PIDD) in their family. All referred couples with a family history of PIDD and a tendency for PND were included in this project. Based on gestational age, chorionic villus sampling (CVS) was performed to analyze the molecular defect of the fetus according to the previous gene defect of the affected case in the family. Postnatal confirmation was performed by immunological screening tests. In a total of 100 cases, CVS was not evaluated in 19 patients due to unwillingness (n=5), late prenatal referral (n=7), miscarriage before CVS (n=3), and female fetus with x-linked diseases in previous children (n=4). In the remaining 81 patients, heterozygous and homozygous mutations were found in 33 and 23 cases, respectively. The hemizygous mutation was obtained in 6 and no pathogenic mutations were found in 19 individuals. Postnatal evaluations revealed that a total of 65 babies were healthy, 32 fetuses were aborted (3 cases before CVS, 2 spontaneous abortions of a healthy and as affected fetus in the CVS subgroup, and 27 cases were aborted due to therapeutic causes). One fetus from the heterozygous subgroup was spontaneously aborted with severe combined immunodeficiency (SCID) and one fetus from the homozygous subgroup that was supposed to be healthy was affected by the autosomal dominant-chronic granulomatous disease (AR-CGD). The diagnostic error was 1.2%. PND is highly recommended in families with a history of PID in their previous child to prevent an affected baby being born and to reduce the government, family, and personal burden of these diseases.

Co-inhibitory molecules modulate immune responses. Immunomodulatory properties of mesenchymal stem cells (MSCs) turn them into ideal candidates for cell therapy. This study was designed to investigate the immunomodulatory effect of adipose-derived stem cells (ASCs) on inflammatory environment of a co-culture of allogenic peripheral blood mononuclear cells (PBMCs) in a two-way mixed leukocyte reaction (twMLR) setting. ASCs were co-cultured with allogenic PBMCs in twMLR setting for four days. The proliferation of peripheral blood mononuclear cells (PBMCs), levels of interleukin (IL)-10, and expression of interferon-gamma (IFN-γ), B7-1, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), programmed death-ligand 1 (PD-L1), +, and CD200R1 genes, as well as cell surface expression of CD200 and CD200R1, were measured in twMLR as control, and co-culture groups on days 0, 2 and 4 of the experiment. The proliferation of PBMCs was suppressed on days 2 and 4 of co-culture. The expression of CD200 (p=0.014), CD200R1, CTLA-4, and PD1 genes increased on days 2 and 4 of the co-culture compared to twMLR. CD200 expressing PBMCs decreased by 1.75% on day 2 of the co-culture but increased by 6.23% on day 4 of the co-culture (p=0.013) compared to the same days of twMLR. IL-10 levels increased in the co-culture supernatants on days 2 and 4 compared to twMLR (p<0.05). Our results showed that ASCs upregulate the CD200/CD200R1 axis more than PD-1/PD-L1 and CTLA-4/B7-1 pathways in the twMLR. Also, elevated expression of CD200R1 in the final day of co-culture was similar to PD-1 expression pattern. This finding suggests a role for the CD200/CD200R1 axis in later modulation of the immune response.

The H1N1 influenza virus is known as a serious pandemic threat across the globe. Vaccination is one of the most effective methods of protection against this virus and the way to reduce the seasonal pandemic risk. The commercial vaccine does not adequately respond to pandemic strains. This study examines the potential function of formulated H1N1 hemagglutinin with MF59 adjuvant against A/PR/8/34 (H1N1). To this end, a recombinant hemagglutinin (rHA) gene of influenza A virus was designed and expressed in SF9 cell by the Baculovirus expression system. Four groups of mice were immunized by rHA in combination with MF59, Alum adjuvant, and virus split only. The immunized mice subsequently used for the humoral immune assay and the results compared with untreated mice (negative group). Besides, both treated and control mice groups were challenged with mouse-adapted influenza virus A/PR/8/34(H1N1) through the intranasal drop. Bodyweight, survival, temperature variation, and the medical conditions of the samples were assessed. Mice immunized with the recombinant protein demonstrated a humoral response to the influenza A virus. Upon virus challenging, co-administration of rHA with MF59 adjuvant could lead to 92% survival of the vaccinated mice within 10 days. The MF59-treated group showed slight weight loss and hightemperature body two weeks after infection. This group also displayed a higher hemagglutination inhibition (HI) antibody titer as compared to the group vaccinated with virus split, and Alum adjuvant. Altogether, the results showed that the recombinant protein with the MF59 adjuvant created better safety than the Alum adjuvant, thereby can be considered as a safe and reliable vaccine against the H1N1 virus for further investigations.

Vitamin D plays a variety of physiological functions, such as regulating mineral homeostasis. More recently, it has emerged as an immunomodulator player, affecting several types of immune cells, such as regulatory T (Treg) cells. It has been reported that vitamin D exerts some mediatory effects through an epigenetic mechanism. In this study, the impacts of calcitriol, the active form of vitamin D, on the methylation of the conserved non-coding sequence 2 (CNS2) region of the forkhead box P3 (Foxp3) gene promoter, were evaluated. Fourteen C57BL/6 mice were recruited in this study and divided into two intervention and control groups. The CD4+ T cells were isolated from mice splenocytes. The expression of Foxp3, IL-10, and transforming growth factor-beta (TGF-β1) genes were relatively quantified by real-time PCR technique, and the DNA methylation percentage of every CpG site in the CNS2 region was measured individually by bisulfite-sequencing PCR. Vitamin D Intervention significantly (p<0.05) could increase the expression of Foxp3, IL-10, and TGF-β1 gene in the CD4+ T cells of mice comparing with the control group. Meanwhile, methylation of the CNS2 region of Foxp3 promoter was significantly decreased in three of ten CpG sites in the vitamin D group compared to the control group. The results of this study showed that vitamin D can engage the methylation process to induce Foxp3 gene expression and probably Treg cytokines profile. Further researches are needed to discover the precise epigenetic mechanisms by which vitamin D modulates the immune system.

Vitiligo is the most common cause of skin, hair, and oral depigmentation which is known as an autoimmune disorder. Genetic and environmental factors have important roles in the progression of the disease. Dysregulation of gene expression, like microRNAs (miRNA), may serve as major relevant factors. Several biological processes are involved in vitiligo disease and developing a comprehensive approach helps us to better understand the molecular mechanisms of disease. In this research, we describe how a weighted gene co-expression network analysis as a systems biology approach assists to define the primary gene modules, hub genes, and messenger RNA (mRNA)-miRNA regulatory network in vitiligo disease as the novel biomarkers. The results demonstrated a module with a high correlation with vitiligo state. Moreover, gene enrichment analysis showed that this module's genes were mostly involved in some biological activities including G protein-coupled receptors signaling pathway, lymphocyte chemotaxis, chemokine activity, neutrophil migration, granulocyte chemotaxis, etc. The co-expression network was constructed using top hub genes of the correlated module which are named as CXCL10, ARL9, AKR1B10, COX7B, RPL26, SPA17, NDUFAF2, RPF2, DAPL1, RPL34, CWC15, NDUFB3, RPL26L1, ACOT13, HSPB11, and NSA2. MicroRNAs prediction tool (miRWalk) revealed top miRNAs correlated with the interested module. Finally, a drug-target network was constructed which indicated interactions of some food and drug administration (FDA) approved drugs with hub genes. Our findings specified one important module and main hub genes which can be considered as novel biomarkers for vitiligo therapeutic purposes.

The exact mechanisms of Adenoid hypertrophy (AHT) pathogenesis and otitis media with effusion (OME) are unclear but there is increasing evidence that allergies may play a role. We aimed to investigate the prevalence of atopy and the effect of anti-allergic drugs in patients with AHT and OME. In a non-randomized, prospective cross-sectional study, 122 patients younger than 18 years of age with AHT or OME were included. Atopic patients based on clinical symptoms of allergic disorders and/or elevated levels of total serum immunoglobulin E (IgE) were referred to allergists and tested for allergen sensitization by skin prick test (SPT). Atopic patients were treated with nasal corticosteroids and antihistamines. Response to treatment was evaluated by comparing symptoms score before and after the treatment. In this study 122 patients were evaluated, 116 of them had AHT and 30 patients had OME. The mean age of participants was 6.7±2.4 years old and 68 of them (55.7%) were male. Allergic symptoms were observed in 38 patients with AHT (32.7%) and nine patients with OME (30%). Among the total cases, 34 patients (28%) were considered atopic. SPT was performed on 25 (73%) cases of atopic patients, with 11 (44 %) positive results. The mean symptom score of AHT and OME decreased significantly after treatment respectively, (p=0.001, p=0.007). According to this study, atopy was relatively common in patients with AHT and OME. Treatment with nasal corticosteroid and antihistamines were effective in these patients.

Multiple sclerosis (MS) is an inflammatory autoimmune disease of the central nervous system, in which proinflammatory cytokines play a critical role in the pathogenic formation of lesions. Caspase-1 is a cysteine protease that proteolytically cleaves precursors of interleukin (IL)-18 and IL-1β and turns them into their active forms. These inflammatory cytokines play an important role in the development of MS. The aim of the present study was the investigation of caspase-1 and its downstream products, IL-18 and IL-1β, in relapsing-remitting MS (RRMS) patients. In this study, we used an ELISA assay to measure serum and cellular caspase-1 and serum levels of IL-18 and IL-1β in RRMS patients in the relapse phase (n=23) and healthy age-and gender-matched controls (n=19). We observed that the caspase-1 level was significantly increased in the serum of MS patients compared to the healthy controls (p=0.03). Although caspase-1 concentration in the lysate of peripheral blood mononuclear cells (PBMCs) was higher than serum among patients and controls (p<0.001), no significant difference was found in cellular levels of caspase-1 between the two groups. There was no significant difference in serum levels of IL-18 and IL-1β between patients and controls. In this study, we found an elevation of extracellular caspase-1, as a reflection of its intracellular level, in the serum of RRMS patients during the relapse phase. Therefore, it suggests being a suitable peripheral biomarker of disease activity in multiple sclerosis.

Bone morphogenetic proteins (BMPs) and wingless (Wnt) signaling molecules and their antagonists, such as sclerostin and noggin, have been identified to have different effects on bone metabolism. This research intended to evaluate the transcript levels of CTNNB1 (catenin beta 1protein), SOST (sclerostin protein), BMP4 (Bone Morphogenetic Protein 4 protein), and NOG (noggin protein) bone metabolism-related genes in peripheral blood mononuclear cells (PBMCs) from condylar hyperplasia (CH) patients in comparison to rheumatoid arthritis (RA), ankylosing spondylitis (AS), and healthy individuals. PBMCs were separated from blood samples of 10 patients with CH, AS, RA, and 10 healthy controls. SYBR Green real-time polymerase chain reaction (PCR) was used for quantitative analysis of CTNNB1, SOST, BMP4, and NOG messenger RNAs (mRNAs). The expression of CTNNB1 was significantly upregulated in CH and AS patients compared with healthy individuals and RA patients. The difference of SOST expression was not significant between all groups. The BMP4 expression was significantly downregulated in AS, CH, and RA patients compared with healthy controls. The NOG expression was downregulated in RA, AS, and CH groups, however, it was only significant in CH and RA patients compared with controls.CH and AS patients were distinguished from RA by the upregulatedCTNNB1 expression. These results demonstrated that CTNNB1, BMP4, and NOG, but not SOST, may contribute to the pathogenesis of CH, AS, and RA.

Sometimes allergic reactions caused by various food allergens often hidden in the composition of medications can mistakenly be diagnosed as drug allergies. Such reactions can especially be unexpected if antihistamines-virtually designed to treat allergy symptoms, are imitated. We present the case of a 37-year-old female patient with cutaneous allergic reaction initially diagnosed as drug allergy to desloratadine/aerius, a desloratadine-containing antihistamine medication. The diagnostic search began with the anamnestic data of the patient about an allergy to cooked corn in her childhood, current seasonal allergic rhinitis, and hand dermatitis probably related to her professional activity. Skin tests and additional laboratory examinations led to diagnosing corn/maize allergy manifested as both food (mainly) and pollen allergy. Besides, it was concluded that hand dermatitis also can becaused by cornstarch contained in medical gloves. Finally, based on the results of a drug challenge test performed with two desloratadine-containing medications–desloratadine/aerius containing cornstarch as an excipient and desloratadine/lordestinenot containing cornstarch, the causative significance of corn was confirmed. Thus, the initial diagnosis of drug allergy was changed to that of food allergy.

Linear IgA bullous dermatosis (LABD) is a rare autoimmune blistering disease that may be triggered by some diseases and medications. For the latter one, non-steroidal anti-inflammatory drugs (NSAIDs) have been identified as one of the potential causative agents to develop LABD. Here, a rare case of drug-induced LABD is introduced. A 13-month-old Iranian boy presented with a history of generalized blisters, displaying the classic “string of pearls” sign who was eventually diagnosed as a case of LABD. In his admission, he was diagnosed whit Mucocutaneous lymph node syndrome and treated with aspirin.  Some features like appearing the characteristic lesions one week following the administration of aspirin, rapid clearance of lesions after the withdrawal of the drug, and reappearance of new lesions after readministration of aspirin were highly suggestive of aspirin-induced LABD. To establish the diagnosis, we used the “Naranjo probability score” which determined the probable causative role of aspirin. The diagnosis was confirmed by showing the positive IgA deposition in the basement membrane zone in a direct immunofluorescence study of the skin biopsy. The child was treated with dapsone with dramatical response to the drug.