Amir Hossein Mansourabadi; Mona Sadeghalvad; Hamid-Reza Mohammadimotlagh; Aliakbar Amirzargar
Abstract
The COVID-19 pandemic is probably the most devastating worldwide challenge in recent century. COVID-19 leads to a mild to severe respiratory disease and affects different organs and has become a global concern since December 2019. Meanwhile, molecular biology and diagnostic laboratories played an essential ...
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The COVID-19 pandemic is probably the most devastating worldwide challenge in recent century. COVID-19 leads to a mild to severe respiratory disease and affects different organs and has become a global concern since December 2019. Meanwhile, molecular biology and diagnostic laboratories played an essential role in diagnosis of the disease by introducing serological and molecular tests. Molecular-based techniques are reliable detection tools for SARS-CoV-2 and used for diagnosis of patients especially in the early stage of the disease. While, serological assays are considered as additional tools to verify the asymptomatic infections, tracing previous contacts of individuals, vaccine efficacy, and study the seroprevalance. The average time of the appearance of anti-SARS-CoV-2 antibodies in the patient's serum is 3-6 days after the onset of symptoms for both IgM and IgA and 10-18 days for IgG. Following the outbreak of COVID-19, FDA has approved and authorized a series of serological laboratory tests for early diagnosis. Serological assays have low-cost and provide fast results but have poor sensitivity in the early stage of the viral infection. Although the serological tests may not play an important role in the active case of COVID-19, it could be effective to determine the immunity of health care workers, and confirm late COVID-19 cases during the outbreak. In this review, we compared various laboratory diagnostic assays for COVID-19.
Parham Nejati; Marzieh Attar; Maryam Rahimian; Davood Fathi; Majid Shahbazi
Volume 14, Issue 3 , September 2017, , Pages 231-239
Abstract
Background: Multiple sclerosis (MS), as a multifactorial autoimmune disease with complex genetic basis, causes demyelination in the central nervous system via cytokine responses to myelin antigens. Myelin basic protein (MBP) is the main protein component of the myelin sheath. HLA-DRB (human leukocyte ...
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Background: Multiple sclerosis (MS), as a multifactorial autoimmune disease with complex genetic basis, causes demyelination in the central nervous system via cytokine responses to myelin antigens. Myelin basic protein (MBP) is the main protein component of the myelin sheath. HLA-DRB (human leukocyte antigen-DR beta) alleles, particularly HLA-DRB1*1501, may be of significance in the pathogenesis of MS. Objective: To examine the association of HLA-DRB1*1501 alleles and MBP VNTR (variable number tandem repeat) polymorphism with the MS susceptibility in Iranian population. Methods: Genomic DNA was extracted from peripheral blood. The alleles were determined by the Polymerase Chain Reaction (PCR) method in 259 MS patients and 312 healthy control individuals and analyses were carried out using Fisher's exact test. Results: The frequencies of MBP VNTR genotypes (AA, AB and BB) were 47%, 42% and 11% among patients, and 45%, 43% and 12% in control subjects, respectively. HLA-DRB1*1501 allele was more frequent among patients than healthy individuals (OR=1.65, P=0.0045). The frequency of allele A and genotype A/A was significantly higher among HLA-DRB1*1501 positive patients (61% and 32%) than controls (46% and 19%) (OR=1.88, P=0.0013; A/A vs. B/B: OR=5.09, P=0.0004). The two-locus analysis of the interaction between the MBP VNTR polymorphism and the HLA-DRB1 allele showed that the HLADRB1* 1501/A haplotype was more frequent among MS patients than the healthy controls. Conclusion: The interaction between the HLA-DRB1*1501 allele and MBP gene may be considered as a predisposing factor in the development and pathogenesis of MS in the case of gene-gene interaction.
Behnam Mohammadi-Ghalehbin; Gholam Reza Hatam; Bahador Sarkari; Mehdi Mohebali; Zabih Zarei; Mansoureh Jaberipour; Shahab Bohlouli
Volume 8, Issue 4 , December 2011, , Pages 244-250
Abstract
Background: Visceral leishmaniasis (VL) is caused by Leishmania infantum in Mediterranean basin and is an endemic disease in some parts of Iran. Canines are the main reservoirs of VL in most of the endemic areas. Different serological methods have been introduced for diagnosis of canine visceral leishmaniasis ...
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Background: Visceral leishmaniasis (VL) is caused by Leishmania infantum in Mediterranean basin and is an endemic disease in some parts of Iran. Canines are the main reservoirs of VL in most of the endemic areas. Different serological methods have been introduced for diagnosis of canine visceral leishmaniasis (CVL). Objective: In this survey a Fucose-Mannose Ligand (FML) ELISA, using native L. infantum antigen, was developed and its validity for detection of infected dogs in comparison with direct agglutination test (DAT) and PCR was evaluated. Methods: Blood samples of sixty ownership dogs (≤ 3 years old) were collected from Meshkin-shahr district in Ardabil province, North-west of Iran. Sera were separated for serological assays (DAT and FMLELISA) and the buffy coats were collected for molecular evaluation. Results: Two out of the 60 (3.33%) samples were found to be positive (antibody titer of ≥ 1/320) in DAT while seven of the 60 (11.66%) samples were positive by FML-ELISA. Nine out of 60 (15%) buffy coat samples showed a band about 680 bp indicative of L. infantum in PCR. Three out of 60 dogs had Kala-azar symptoms and were positive by PCR and FML-ELISA, while two of these three dogs had antibody titers >1/320 in their serum samples. The sensitivity and specificity of FML-ELISA for the detection of CVL in both symptomatic and asymptomatic dogs were found to be 77.8% and 100%, respectively. Conclusion: Considering the acceptable sensitivity and high specificity of FMLELISA, use of this serological method can be recommended for epidemiological surveys of CVL.
Salomeh Fouladi; Minoo Adib; Mansoor Salehi; Hadi Karimzadeh; Zahra Bakhshiani; Vajiheh Ostadi
Volume 6, Issue 1 , March 2009, , Pages 49-54
Abstract
Background: HLA-B*27 is strongly associated with ankylosing spondylitis (AS). It represents a family of alleles that differ among ethnic groups. Objective: The aim of this study was to determine the distribution of HLA-B*27 alleles in AS patients and healthy controls in Isfahan (Iran). Methods: Sixty ...
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Background: HLA-B*27 is strongly associated with ankylosing spondylitis (AS). It represents a family of alleles that differ among ethnic groups. Objective: The aim of this study was to determine the distribution of HLA-B*27 alleles in AS patients and healthy controls in Isfahan (Iran). Methods: Sixty AS patients and 430 healthy blood donors were selected. All subjects were HLA-B*27 positive by flow cytometry. HLAB* 27 subtypes were determined by PCR-SSP. Results: Forty patients (66.7%) and 17 controls (3.95%) were HLA-B*27 positive. Subtypes detected by PCR-SSP were B*2705, B*2702, B*2704 and B*2707. One patient was B*2702/B*2710. No significant difference was found in the distribution of these alleles between AS patients and controls. Conclusion: Although Caucasian subtypes are predominant among Iranians, this population is characterized by a combination of both specific Caucasian and Oriental subtypes. However such results should be interpreted carefully because of the small sample size in our investigation and definitive conclusion awaits more ethnicgroup studies.
Behzad Haghpanah; Mansoor Salehi; Shahram Sadri
Volume 3, Issue 1 , March 2006, , Pages 47-53
Abstract
Background: Toxoplasmosis is a zoonotic disease with high seroprevalence worldwide. Several immunological methods have been described for diagnosis of toxoplasmosis. Objective: To determine the parasitemia period in patients infected with toxoplasma using PCR and comparing serological data with molecular ...
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Background: Toxoplasmosis is a zoonotic disease with high seroprevalence worldwide. Several immunological methods have been described for diagnosis of toxoplasmosis. Objective: To determine the parasitemia period in patients infected with toxoplasma using PCR and comparing serological data with molecular results. Methods: 154 serum samples from patients with toxoplasmosis were examined. Presence of parasite DNA was evaluated using PCR method. IgG and IgM antibody titers were measured using IFA test. Results: Of 154 studied samples, 28 were positive for IgM and 60 were positive for IgG with titers higher than 1/400. PCR was performed on those samples having either IgG or IgM titers. Samples with IgM titers lower than 1/800 and higher than 1/3200 had no detectable level of parasite DNA. Parasitemia was detected in cases with IgG titer of 1/100 to 1/200. All samples with no detectable IgM and with IgG titers higher than 1/400 were negative when tested by PCR. Conclusion: IgM specific antibody titer between 1/800 and1/3200 represents a window opportunity in treatment of patients with toxoplasmosis. Absence of parasite DNA in patients with higher IgM antibody titer is explained by the effector mechanism of antibody for clearance of the parasite.
Abbasali Pourazar; Mansoor Salehi; Aabollah Jafarzadeh; Mohammad Kazemi Arababadi; Farzad Oreizi; Keivan Shariatinezhad
Volume 2, Issue 3 , September 2005, , Pages 172-176
Abstract
Background: The risk of infection by transfusion-transmitted viruses has been reduced remarkably. However, a zero-risk blood supply is still desirable. The screening for antibody to HBc (anti-HBc) has been shown as an alternative test for the detection of HBV infection. Objective: The main aim of this ...
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Background: The risk of infection by transfusion-transmitted viruses has been reduced remarkably. However, a zero-risk blood supply is still desirable. The screening for antibody to HBc (anti-HBc) has been shown as an alternative test for the detection of HBV infection. Objective: The main aim of this study was to evaluate HBV infection markers and the potential value of anti-HBc testing of blood donors to detect HBV infection. Methods: In this descriptive cross-sectional study, 545 blood samples were collected and tested for HbsAg using ELISA method. Then all HBsAg negative samples were tested for anti-HBc by the same method. To detect HBV infection, all HBsAg negative and anti-HBc positive samples were tested by PCR for HBV DNA. Results: All blood samples were HBsAg negative of which, 43 (8%) were anti-HBc positive. From those which were positive for anti-HBc, five samples were also positive for HBV DNA. Conclusion: Occult HBV infection is a clinical form of HBV infection in which HBsAg is not expressed by HBV and blood samples cannot be screened by ELISA method, therefore more sensitive techniques are needed. Our results demonstrate that a complementary test such as PCR, for detecting HBV DNA, is essential to ensure safety of blood samples.
Behrouz Nikbin; Nader Tajik; Ali Saraji; Gholam Reza Pourmand; Fatemeh Talebian; Abdurasul Mehrsai; Ali Akbar Amirzargar
Volume 1, Issue 3 , December 2004, , Pages 162-168
Abstract
Background: The Presence of donor leukocytes in recipients of organ allograft has been shown even several years after transplantation. However, it remains unclear whether this donor cell microchimerism plays an effective role in allograft acceptance or is simply a consequence of immunosuppressive conditions ...
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Background: The Presence of donor leukocytes in recipients of organ allograft has been shown even several years after transplantation. However, it remains unclear whether this donor cell microchimerism plays an effective role in allograft acceptance or is simply a consequence of immunosuppressive conditions in recipients. Objective: To study microchimerism in a group of kidney transplant recipients. Methods: In this study, the Peripheral Blood Microchimerism (PBM) after renal transplantation was retrospectively evaluated in 32 male-to-female recipients of living (unrelated) and cadaveric donor renal transplants. Using a Nested Polymerase Chain Reaction (Nested-PCR) amplification specific for SRY region of the Y chromosome, microchimerism was detected with a sensitivity of 1:1000000. Recipients were classified and compared according to the presence of PBM, acute and chronic rejection episodes, type of allotransplant, recipient and donor age at transplantation, previous male labor or blood transfusion, allograft function (serum creatinine level), and body mass index. Results: Among 32 recipients, 7 (21.9) were positive for PBM in multiple testing at different post-transplantation times. All microchimeric recipients had received kidney from living-unrelated donors. No significant difference was observed with regard to other parameters mentioned above. In addition, acute rejection rate in the microchimeric group was 3 (42%) versus 4 (16%) in the nonmicrochimeric recipients (not significant). Conclusion: Our results demonstrate better establishment of microchimerism after living donor kidney transplantation. However, concerning the true effect of microchimerism after renal transplantation doubt still persists; and it seems that microchimerism alone has no major protective role in renal allograft survival.