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1.
Sensors (Basel) ; 23(2)2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36679468

RESUMEN

Human antibodies are produced due to the activation of immune system components upon exposure to an external agent or antigen. Human antibody G, or immunoglobin G (IgG), accounts for 75% of total serum antibody content. IgG controls several infections by eradicating disease-causing pathogens from the body through complementary interactions with toxins. Additionally, IgG is an important diagnostic tool for certain pathological conditions, such as autoimmune hepatitis, hepatitis B virus (HBV), chickenpox and MMR (measles, mumps, and rubella), and coronavirus-induced disease 19 (COVID-19). As an important biomarker, IgG has sparked interest in conducting research to produce robust, sensitive, selective, and economical biosensors for its detection. To date, researchers have used different strategies and explored various materials from macro- to nanoscale to be used in IgG biosensing. In this review, emerging biosensors for IgG detection have been reviewed along with their detection limits, especially electrochemical biosensors that, when coupled with nanomaterials, can help to achieve the characteristics of a reliable IgG biosensor. Furthermore, this review can assist scientists in developing strategies for future research not only for IgG biosensors but also for the development of other biosensing systems for diverse targets.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Sarampión , Paperas , Rubéola (Sarampión Alemán) , Humanos , COVID-19/diagnóstico , Inmunoglobulina G , Anticuerpos Antivirales
2.
Infect Dis (Lond) ; 55(3): 216-220, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36625442

RESUMEN

BACKGROUND: There are limited data on the rates of the waning of antibody levels after two-dose and booster vaccination according to the different platforms of COVID-19 vaccines. METHODS: We enrolled healthcare workers (HCWs) in a tertiary care hospital who received homologous two-dose vaccination, followed by a homologous or heterologous booster mRNA vaccine. SARS-CoV-2 S1-specific IgG was measured using ELISA. A linear mixed regression model was used to compare the slope from the peak antibody titre to the lowest antibody titres 3 months after vaccination. RESULTS: A total of 113 HCWs (BNT162b2 (n = 48 [42%]), ChAdOx1 nCoV-19 (n = 52 [46%]) or mRNA-1273 (n = 13 [12%])) were enrolled in this prospective cohort study. More gradual antibody waning was observed over 3 months with the two-dose ChAdOx1 nCoV-19 (ChAdOx1) than with the two-dose BNT162b2 or mRNA-1273 (p < 0.001 and p = 0.001, respectively). In addition, homologous mRNA-1273 booster induced a more durable antibody response than homologous BNT162b2 booster (p < 0.001) or heterologous ChAdOx1-BNT162b2 booster (p < 0.001). CONCLUSIONS: Two-dose homologous ChAdOx1 vaccination or homologous mRNA-1273 booster appears to induce more-durable antibody responses than 2-dose homologous mRNA vaccination, homologous BNT162b2 booster, or 2-dose ChAdOx1 followed by BNT62b2 booster, although our findings are based on the relatively short term (3-month) follow-up after the vaccinations and the evaluation of the slopes from different antibody peak levels. Further studies on long-term durability depending on the types of vaccines are needed.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Humanos , Inmunidad Humoral , Vacuna BNT162 , ChAdOx1 nCoV-19 , Vacuna nCoV-2019 mRNA-1273 , Estudios Prospectivos , COVID-19/prevención & control , SARS-CoV-2 , Anticuerpos Antivirales , Inmunoglobulina G , Vacunación
3.
Commun Biol ; 6(1): 100, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36697496

RESUMEN

Human milk contains SARS-CoV-2-specific antibodies after COVID-19 vaccination. These milk antibodies decrease several months post-vaccination. Whether booster immunization restores human milk antibody levels, potentially offering prolonged passive immunity for the infant, remains unknown. In this prospective follow-up study, we investigated the longitudinal SARS-CoV-2-specific antibody response in human milk of 26 lactating women who received a COVID-19 booster dose of an mRNA-based vaccine. Moreover, we evaluated whether the booster-induced human milk antibody response differs for participants who received a similar or different vaccine type in their primary vaccination series. All participants (100%) who received a homologous booster vaccination showed SARS-CoV-2-specific immunoglobulin A (IgA) and immunoglobulin G (IgG) in their milk. Heterologous booster vaccination resulted in milk conversion for 9 (69%) and 13 (100%) participants for IgA and IgG respectively. Findings of this study indicate that both homologous and heterologous boosting schedules have the potential to enhance SARS-CoV-2-specific IgA and IgG in human milk.


Asunto(s)
COVID-19 , Leche Humana , Lactante , Humanos , Femenino , SARS-CoV-2 , Formación de Anticuerpos , Vacunas contra la COVID-19 , Estudios de Seguimiento , Lactancia , Estudios Prospectivos , COVID-19/prevención & control , Anticuerpos Antivirales , Inmunoglobulina G , Inmunoglobulina A
4.
Mediators Inflamm ; 2023: 7590549, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36714243

RESUMEN

Objectives: Helicobacter pylori (H. pylori) immunoglobulin G (IgG) seropositivity is prevalent, but its correlation with homocysteine (Hcy), a biomarker of vascular risk events, is unclear. This study is aimed at exploring the correlation of H. pylori IgG seropositivity and plasma Hcy levels in adults. Methods: Data was obtained from the National Health and Nutrition Examination Survey (NHANES) cycle 1999-2000. Hcy was measured by the Abbott homocysteine assay, and H. pylori IgG was measured by enzyme-linked immunosorbent assays. The weighted multiple logistic regression analyses with adjustments for potential confounders were conducted. Subgroup analyses stratified by gender, age, and race were performed. Results: A total of 4029 subjects aged 20-85 years were included. Population prevalence of H. pylori IgG seropositivity was 44.7% in the overall population with higher prevalence found in those with older age, Mexican Americans, lower education, and lower household income. Levels of plasma Hcy were not elevated in those with H. pylori IgG seropositivity versus seronegativity (ß -0.120 (-0.438, 0.199) P = 0.462). This difference was not significant after stratifying by gender and age. However, in the subgroup analyses stratified by race, a negative correlation between H. pylori seropositivity and plasma Hcy levels was observed in Mexican Americans (ß -0.802 (-1.253, -0.352) P < 0.001). Conclusions: H. pylori IgG seropositivity was not associated with plasma Hcy levels in the general population, but there may be a negative correlation in Mexican Americans. These findings provide new insights to advance the research of the link between plasma Hcy levels and stomach health.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Humanos , Adulto , Encuestas Nutricionales , Ensayo de Inmunoadsorción Enzimática , Biomarcadores , Anticuerpos Antibacterianos , Inmunoglobulina G
5.
PLoS Negl Trop Dis ; 17(1): e0011019, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36608168

RESUMEN

BACKGROUND: There have been significant improvements in Chagas disease therapy and it is now widely accepted that most patients with chronic disease might benefit from therapy. However, there are challenges to monitor drug efficacy and cure for these patients, which are important impediments for current and future therapies. Trypanosoma cruzi-PCR is highly variable while IgG seroconversion takes decades yielding variable results depending on the antigen(s) used for the assay. METHODS AND RESULTS: We used the genomic phage display (gPhage) platform to perform a pairwise comparison of antigens and epitopes recognized by twenty individual patients with chronic Chagas disease before and after treatment with benznidazole. In total, we mapped 54,473 T. cruzi epitopes recognized by IgG from individual patients (N = 20) before benznidazole treatment. After treatment, the number of epitopes recognized by all patients was significantly smaller (21,254), a reduction consistent with a decrease in anti-T. cruzi antibodies. Most of these epitopes represent distinct fragments from the same protein and could, therefore, be grouped into 80 clusters of antigens. After three years of treatment with benznidazole, we observed a 64% reduction in the number of clusters of antigens recognized by patients (59 clusters before versus 21 clusters after treatment). The most abundant antigenic clusters recognized by patients correspond to the surface antigen CA-2 (B13) followed by the microtubule associated antigen, which highlights the value of these epitopes in Chagas disease diagnosis. Most importantly, quantitative pairwise comparison of gPhage data allowed for the prediction of patient response to treatment based on PCR status. PRINCIPAL FINDING: Here, we compiled a list of antigens and epitopes preferentially recognized by Chagas disease patients before and after benznidazole treatment. Next, we observed that gPhage data correlated with patient PCR-status and could, therefore, predict patient response to treatment. Moreover, gPhage results suggest that overall, independent of PCR status, treatment led to a reduction in the presence of T. cruzi-specific antibody levels and the number of antigens and epitopes recognized by these patients. CONCLUSION: The gPhage platform use of unbiased library of antigens, which is different from conventional serological assays that rely on predetermined antigens, is a contribution for the development of novel diagnostic tools for Chagas disease.


Asunto(s)
Bacteriófagos , Enfermedad de Chagas , Nitroimidazoles , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Enfermedad de Chagas/diagnóstico , Nitroimidazoles/uso terapéutico , Epítopos , Inmunoglobulina G
6.
Anal Chem ; 95(2): 836-845, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36592029

RESUMEN

Although safe and efficacious coronavirus disease-2019 (COVID-19) vaccines are available, real protective immunity is revealed by the serum COVID-19 neutralizing antibody (NAb) concentration. NAbs deactivate the virus by attaching to the viral receptor-binding domain (RBD), which interacts with angiotensin-converting enzyme 2 (ACE2) on the human cell. This paper introduces inexpensive, rapid, sensitive, and quantifiable impedance-based immunosensors to evaluate the NAb. The sensor limit of detection is experimentally determined in different buffer dilutions using bovine IgG-anti-bovine IgG interaction. The dominance of AC electrokinetic transport and molecular diffusion in the sensor is investigated using scaling analysis and numerical simulations. The results demonstrated that the sensor detection mechanism is mainly based on the diffusion of the biomolecules onto the electrode surface. After evaluating the sensor working principles, viral RBD buffers, including different NAb concentrations, are applied to the sensor, immobilized with the human ACE2 (hACE2). Results demonstrate that the sensor is capable of NAb detection in the analytical measuring interval between 45 ng/mL and 185 ng/mL. Since the present sensor provides fast test results with lower costs, it can be used to assess the NAb in people's blood serum before receiving further COVID vaccine doses.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Humanos , COVID-19/diagnóstico , Anticuerpos Neutralizantes , Enzima Convertidora de Angiotensina 2 , Vacunas contra la COVID-19 , SARS-CoV-2/metabolismo , Impedancia Eléctrica , Inmunoensayo , Anticuerpos Antivirales , Receptores Virales/metabolismo , Inmunoglobulina G
7.
Lab Chip ; 23(2): 251-260, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36598080

RESUMEN

Enzyme-linked immunosorbent assay (ELISA) is widely employed for detecting target molecules in bioassays including the serological assays that measure specific antibody titers. However, ELISA tests are inherently limited to centralized laboratories staffed with trained personnel as the assay workflow requires multiple steps to be performed in a specific sequence. Here, we report a dipstick ELISA test that automates this otherwise laborious process and reports the titer of a target molecule in a digital manner without the need for an external instrument or operator. Our assay measures titer by gradually immuno-depleting the target analyte from a flowing sample effectively diluting the residual target - a process conventionally achieved through serially diluting the whole sample in numerous, time-consuming pipetting steps performed manually. Furthermore, the execution of the depletion ELISA process is automated by a built-in flow controller which sequentially delivers different reagents with preset delays. We apply the technology to develop assays measuring (1) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody titers (IgM/IgG antibodies to nucleocapsid and spike protein) and (2) troponin I, a cardiac biomarker.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Anticuerpos Antivirales , Inmunoglobulina G , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina M , Sensibilidad y Especificidad
8.
J Int Med Res ; 51(1): 3000605221147188, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36636770

RESUMEN

OBJECTIVES: To evaluate the effect of zinc supplementation on immunotoxicity induced by subchronic oral exposure to glyphosate-based herbicide (GBH). METHODS: Sixty adult male Wistar rats randomly divided equally into six groups were exposed to GBH by gavage daily for 16 weeks with or without zinc pretreatment. Group DW rats received distilled water (2 mL/kg), group Z rats received zinc (50 mg/kg), and group G1 and G2 rats received 187.5 and 375 mg/kg GBH, respectively. Group ZG1 and ZG2 rats were pretreated with 50 mg/kg zinc before exposure to 187.5 and 375 mg/kg GBH, respectively. Tumor necrosis factor alpha (TNF-α) and immunoglobulin (IgG, IgM, IgE) levels were measured by enzyme-linked immunosorbent assay. Spleen, submandibular lymph node, and thymus samples were processed for histopathology. RESULTS: Exposure to GBH (G1 and G2) significantly increased serum TNF-α concentrations and significantly decreased serum IgG and IgM concentrations compared with the control levels. Moderate-to-severe lymphocyte depletion occurred in the spleen, lymph nodes, and thymus in the GBH-exposed groups. Zinc supplementation mitigated the immunotoxic effects of GBH exposure. CONCLUSIONS: GBH exposure increased pro-inflammatory cytokine responses, decreased immunoglobulin production, and depleted lymphocytes in lymphoid organs in rats, but zinc supplementation mitigated this immunotoxicity.


Asunto(s)
Herbicidas , Zinc , Animales , Masculino , Ratas , Suplementos Dietéticos , Herbicidas/toxicidad , Inmunoglobulina G , Inmunoglobulina M , Ratas Wistar , Factor de Necrosis Tumoral alfa , Zinc/farmacología
9.
Viral Immunol ; 36(1): 63-70, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36648773

RESUMEN

Understanding the functional characteristics of antibodies produced against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) will assist in the determination of disease outcomes for this virus. In this study, the ability of antibodies to inhibit viral entry into the host cell through the interaction of the receptor binding domain of the viral spike protein and the angiotensin-converting enzyme 2 receptor on the human cell surface was investigated. The SARS-CoV-2 IgG levels in 20 SARS-CoV-2 positive patients were measured using an enzyme-linked immunosorbent assay, and the samples were further analyzed using a functional binding assay. Inhibition of viral infectivity was also measured using a pseudovirus neutralization assay against a D614G SARS-CoV-2 virus strain. A significant correlation between IgG levels and neutralizing antibody 50% inhibitory concentration (IC50) titers was observed (p < 0.05). Similarly, the IC50 titers obtained in the neutralization and binding assays were significantly correlated (p < 0.001). Varying levels of IgG and IC50 titers were observed for the SARS-CoV-2 antibody-positive samples, with one sample not showing any neutralizing capability despite detectable IgG levels. Gender comparisons showed no statistical differences in any of the assays. These results suggest that increased SARS-CoV-2 IgG levels correlate with greater protection against the entry of the virus into cells; however, further investigations in larger studies are needed to confirm the correlates of protection.


Asunto(s)
COVID-19 , Humanos , Enzima Convertidora de Angiotensina 2 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Inmunoglobulina G , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/química
10.
Arch Virol ; 168(2): 69, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36658402

RESUMEN

The aim of this study was to measure the extent of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among workers at the Institut Pasteur de Tunis (IPT), a public health laboratory involved in the management of the COVID-19 pandemic in Tunisia, and to identify risk factors for infection in this occupational setting. A cross-sectional survey was conducted on IPT workers not vaccinated against coronavirus disease 2019 (COVID-19). Participants completed a questionnaire that included a history of reverse transcription-polymerase chain reaction (RT-PCR)-confirmed SARS-CoV-2 infection. Immunoglobulin G antibodies against the receptor-binding domain of the spike antigen (anti-S-RBD IgG) and the nucleocapsid protein (anti-N IgG) of the SARS-CoV-2 virus were detected by enzyme-linked immunoassay (ELISA). A multivariate analysis was used to identify factors significantly associated with SARS-CoV-2 infection. A total of 428 workers were enrolled in the study. The prevalence of anti-S-RBD and/or anti-N IgG antibodies was 32.9% [28.7-37.4]. The cumulative incidence of SARS-CoV-2 infection (positive serology and/or previous positive RT-PCR test) was 40.0% [35.5-44.9], while the proportion with asymptomatic infection was 32.9%. One-third of the participants with RT-PCR-confirmed infection tested seronegative more than 90 days postinfection. Participants aged over 40 and laborers were more susceptible to infection (adjusted OR [AOR] = 1.65 [1.08-2.51] and AOR = 2.67 [1.45-4.89], respectively), while tobacco smokers had a lower risk of infection (AOR = 0.54 [0.29-0.97]). The SARS-CoV-2 infection rate among IPT workers was not significantly different from that detected concurrently in the general population. Hence, the professional activities conducted in this public health laboratory did not generate additional risk to that incurred outside the institute in day-to-day activities.


Asunto(s)
COVID-19 , Humanos , Adulto , Persona de Mediana Edad , COVID-19/epidemiología , SARS-CoV-2 , Incidencia , Salud Pública , Pandemias/prevención & control , Túnez/epidemiología , Estudios Transversales , Factores de Riesgo , Inmunoglobulina G , Anticuerpos Antivirales
11.
BMC Endocr Disord ; 23(1): 5, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36604681

RESUMEN

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has dramatically impacted global health, and patients with type 2 diabetes have been identified as a high-risk group for COVID-19 infection and the development of severe disease. In response, this study aimed to evaluate whether patients with type 2 diabetes infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could develop antibody responses in the same manner as patients without diabetes, and whether there is a difference in antibody response to SARS-CoV-2 between patients with diabetes diagnosed prior to hospitalization, and those with newly diagnosed diabetes. METHODS: SARS-CoV-2-specific immunoglobulin G (IgG) levels were quantified using two iFlash 3000 Chemiluminescence Immunoassay analyzer kits (Shenzhen YHLO Biotech Co., Ltd.) to detect IgG antibodies specific for nucleocapsid protein (IgG-N), and specific for the S1 subunit of the spike protein (IgG-S1). In 124 hospitalized patients with COVID-19, 40 patients with type 2 diabetes were matched to 40 patients without diabetes using propensity score matching (PSM). RESULTS: There was no difference in IgG-N and IgG-S1 levels between the patients with diabetes and those without. Of patients with diabetes, 31 patients had known diabetes and nine patients had newly diagnosed diabetes. The median levels of IgG-N at 7-13 days in patients with newly diagnosed diabetes were significantly lower than those in patients with known diabetes (IgG-N; 10.9 vs. 31.0 AU/mL, p = 0.031, IgG-S1; 7.5 vs. 24.4 AU/mL, p = 0.023). CONCLUSIONS: Even after adjusting for covariates using PSM, COVID-19 patients with type 2 diabetes had comparable antibody responses to patients without diabetes. Patients with newly diagnosed diabetes had lower IgG-N and IgG-S1 production in the second week of the disease compared with those with previously known diabetes.


Asunto(s)
COVID-19 , Diabetes Mellitus Tipo 2 , Humanos , COVID-19/diagnóstico , SARS-CoV-2 , Formación de Anticuerpos , Diabetes Mellitus Tipo 2/complicaciones , Anticuerpos Antivirales , Inmunoglobulina G
12.
BMC Geriatr ; 23(1): 33, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658508

RESUMEN

BACKGROUND: The diagnosis of unilateral eosinophilic pleural effusion (EPE) is difficult, especially for the elderly. IgG4-related disease (IgG4-RD) is a rare cause of EPE. CASE PRESENTATION: An 81-year-old man was admitted to the hospital for dyspnea due to right pleural effusion. Laboratory examination shows elevated IgG4 and eosinophils in both serum and pleural fluid. The patient was diagnosed with IgG4-RD by video-assisted thoracoscopy and pleural biopsy. We found no evidence of other organ involvement except for the EPE and history of prurigo. He was treated with prednisolone 40 mg daily orally and pleural effusion decreased significantly. CONCLUSION: IgG4-RD should be considered in the differential diagnosis of EPE in the elderly. High effusion IgG4 concentration may be an indication of IgG4-related pleural lesions.


Asunto(s)
Enfermedad Relacionada con Inmunoglobulina G4 , Derrame Pleural , Masculino , Humanos , Anciano , Anciano de 80 o más Años , Enfermedad Relacionada con Inmunoglobulina G4/complicaciones , Enfermedad Relacionada con Inmunoglobulina G4/diagnóstico , Enfermedad Relacionada con Inmunoglobulina G4/tratamiento farmacológico , Inmunoglobulina G , Derrame Pleural/diagnóstico , Derrame Pleural/etiología , Derrame Pleural/patología , Biopsia/efectos adversos
13.
Vaccine ; 41(2): 304-314, 2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36587961

RESUMEN

All seasonal influenza vaccines for 2021-2022 in the US were quadrivalent and the market continues to be dominated by intramuscular delivery of non-adjuvanted, virion-derived antigens grown in chicken eggs. Up to four new egg-adapted production influenza vaccine strains must be generated each year. The introduction in 2012 of Flucelvax®, which is grown in mammalian suspension cell culture and uses vaccine production strains without adaptive mutations for efficient growth in eggs, represented a major advance in vaccine production technology. Here we demonstrate that Flucelvax can be reformulated and combined with a liposomal adjuvant containing QS-21 (Verndari Adjuvant System 1.1, VAS1.1) or QS-21 and 3D-PHAD (VAS1.2) for intradermal administration using a painless skin patch, VaxiPatch™. VAS1.2 is similar to AS01B, the adjuvant system used in Shingrix® and Mosquirix™. We show that Flucelvax, when reformulated and concentrated using tangential flow filtration (TFF), maintains hemagglutination and single radial immunodiffusion (SRID) potency. Loading the reformulated Flucelvax material onto VaxiPatch arrays conferred high levels of resistance to heat stress and room temperature stability. TFF enriched vaccine antigens were combined with VAS1.1 or VAS1.2 and dispensed in 10nL drops into the pockets of 36 (total 360 nL) stainless steel microneedles arranged in a microarray 1.2 cm in diameter. Using VaxiPatch delivery of 2 µg of antigen, we demonstrated intramusuclar-comparable IgG and hemagglutination inhibition (HAI) immune responses in Sprague Dawley® rats. With addition of VAS1.2, antigen-specific IgG titers were increased as much as 68-fold (47-fold for VAS1.1) with improvements in seroconversion for three of four strains (all four were improved by VAS1.1). TFF-reformulated antigens combined with VAS1.1 or VAS1.2 and delivered by VaxiPatch showed only minor skin reactogenicity after 1 h and no skin reactogenicity after 24 h. These data indicate that VaxiPatch and the VAS system have the potential to be transformative for vaccine delivery.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Ratas , Animales , Humanos , Estaciones del Año , Ratas Sprague-Dawley , Gripe Humana/prevención & control , Adyuvantes Inmunológicos , Vacunación , Pruebas de Inhibición de Hemaglutinación , Vacunas Combinadas , Anticuerpos Antivirales , Inmunoglobulina G , Inyecciones Intradérmicas , Mamíferos
14.
Egypt J Immunol ; 30(1): 31-41, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36591956

RESUMEN

Since the start of the pandemic, the number of cases has been increased rapidly. Due to asymptomatic and mild cases and restricted testing in many geographic locations, the overall number of actual COVID-19 cases is likely significantly higher than the number of verified cases. Several COVID-19-related comorbid diseases impair immune system function, which has an impact on COVID-19 responsiveness. So, we evaluated the immune response to SARS-CoV-2 after the third wave of COVID-19 and assessed the effect of comorbid diseases on this immune response. The current cross-sectional study was conducted in August 2021 after the third wave of COVID-19. The study included 287 participants. All participants were asked about their epidemiological data, comorbid diseases, data suggesting COVID-19 infection, and precautions measures to minimize the exposure to the disease. Of the 278 participants, 50% had a positive IgG response to COVID-19. Regarding comorbid diseases, the IgG antibody titer was significantly lower in patients with chronic kidney diseases (CKD) on dialysis, ischemic heart disease, and chronic obstructive lung diseases than other participants (p= 0.01, p= 0.02, p= 0.005, respectively). Neither precaution measures nor comorbid diseases had a role in risk factors of COVID-19 infections in our participants. In conclusion, high seroprevalence (50%) of SARS-CoV-2 IgG antibody after the third wave of COVID-19 was observed in the current study. Comorbid conditions as hypertension, chronic cardiac diseases, chronic chest problems, and CKD on dialysis could decrease the immune response against COVID-19 infection.


Asunto(s)
COVID-19 , Humanos , Egipto/epidemiología , Estudios Transversales , ARN Viral , SARS-CoV-2 , Estudios Seroepidemiológicos , Inmunoglobulina G , Anticuerpos Antivirales , Inmunidad
15.
Egypt J Immunol ; 30(1): 49-56, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36591958

RESUMEN

This study aimed to report the dynamic profile of IgG-specific antibodies to SARS-CoV-2 infection for 6 months after infection. We conducted a prospective study, recruited 33 recently confirmed covid -19 patients and collected 6 samples from each patient. The first samples were collected one month from the start of symptoms and subsequent samples collected at 30 days interval. We measured the IgG by chemiluminescent immunoassay (CLIA). According to the disease severity, patients were categorized as asymptomatic 4 (12.1%), mild 14 (42,4%), moderate 9 (27.3%), and severe 6 (18.2%). Patients were 12 (35.3%) females and 21 (64.7%) males. The mean IgG levels maintained a high level till the second month (92.81 ± 110.15 AU/ml) from the onset of symptoms followed by a gradual decrease till the sixth month after infection (17.42 ± 22.61 AU/ml). The patients with severe symptoms significantly exhibited the highest IgG levels, reached the highest level (mean=237.44 ± 164.13 AU/ml) at the second month. While the lowest levels were detected among the asymptomatic patients (mean= 3.04 ± 2.94 AU/ml) at the second month. Older age correlated with higher IgG antibody level (r= 0.350 p=0.046); however, sex was not related to IgG level. In conclusion, Symptomatic COVID-19 disease is followed by protective immunity for more than 6 months. Immunity in asymptomatic patients is low and fades rapidly than symptomatic cases. Patients with severe disease had significantly higher IgG levels compared to mild, moderate, or asymptomatic patients.


Asunto(s)
COVID-19 , SARS-CoV-2 , Femenino , Masculino , Humanos , Inmunoglobulina G , Egipto , Estudios Prospectivos , Inmunidad , Anticuerpos Antivirales , Inmunoglobulina M
18.
Viruses ; 15(1)2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36680289

RESUMEN

The amaranthine scale of the COVID-19 pandemic and unpredictable disease severity is of grave concern. Serological diagnostic aids are an excellent choice for clinicians for rapid and easy prognosis of the disease. To this end, we studied the humoral immune response to SARS-CoV-2 infection to map immunogenic regions in the SARS-CoV-2 proteome at amino acid resolution using a high-density SARS-CoV-2 proteome peptide microarray. The microarray has 4932 overlapping peptides printed in duplicates spanning the entire SARS-CoV-2 proteome. We found 204 and 676 immunogenic peptides against IgA and IgG, corresponding to 137 and 412 IgA and IgG epitopes, respectively. Of these, 6 and 307 epitopes could discriminate between disease severity. The emergence of variants has added to the complexity of the disease. Using the mutation panel available, we could detect 5 and 10 immunogenic peptides against IgA and IgG with mutations belonging to SAR-CoV-2 variants. The study revealed severity-based epitopes that could be presented as potential prognostic serological markers. Further, the mutant epitope immunogenicity could indicate the putative use of these markers for diagnosing variants responsible for the infection.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Inmunidad Humoral , Pandemias , Proteoma , Péptidos , Epítopos , Inmunoglobulina A , Inmunoglobulina G , Glicoproteína de la Espiga del Coronavirus/genética , Anticuerpos Antivirales
19.
BMC Vet Res ; 19(1): 21, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36698186

RESUMEN

BACKGROUND: Hepatitis E Virus (HEV) is recently considered an emerging public health concern. HEV genotypes 1 and 2 are widely distributed and pathogenic only for humans. In contrast, HEV, genotypes 3 and 4 are observed in swine, deer, wild boars and rabbits and can also be transmitted to humans. The presence of HEV in the liver, muscle, faeces, blood, and bile was detected by real-time RT-PCR in 156 pigs belonging to twenty different farms, ranging from 1 to 8 months of age. The phylogenetic analysis was performed on the viral strain present in the positive biological matrix, with the lowest Ct. HEV-IgG and HEV-IgM in the sera were analysed by two different ELISA kits. RESULTS: Twenty-one pigs, i.e., 13.46% of them (21/156, 95% CI: 8.53%-19.84%), tested positive for HEV in at least one biological matrix by real-time RT-PCR, while phylogenetic analysis revealed the presence of HEV subtypes 3f and 3c. Pig serums analysed by ELISA showed an overall prevalence of 26.92% (42/156, 95% CI: 20.14%-34.60%) for HEV-IgG, whereas the 28.95% (33/114, 95% CI: 20.84%-38.19%) of them tested negative resulted positive for the HEV-IgM. CONCLUSIONS: The faeces are the biological matrix with the highest probability of detecting HEV. The best concordance value (Kappa Kohen index) and the highest positive correlation (Phi index) were observed for the correlation between bile and liver, even when the number of positive liver samples was lower than the positive bile samples. This finding may suggest that a higher probability of HEV occurs in the bile, when the virus is present in the liver, during the stages of infection. Finally, the presence of HEV in muscle was observed in 11 pigs, usually used for the preparation of some dishes, typical of the Italian tradition, based on raw or undercooked meat. Therefore, their consumption is a possible source of infection for final consumer.


Asunto(s)
Ciervos , Virus de la Hepatitis E , Hepatitis E , Enfermedades de los Porcinos , Humanos , Porcinos , Animales , Conejos , Virus de la Hepatitis E/genética , Hepatitis E/epidemiología , Hepatitis E/veterinaria , Filogenia , Enfermedades de los Porcinos/epidemiología , Ciervos/genética , Italia/epidemiología , ARN Viral/genética , ARN Viral/análisis , Inmunoglobulina G , Inmunoglobulina M , Sus scrofa/genética
20.
PLoS One ; 18(1): e0280276, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36689402

RESUMEN

BACKGROUND: Reports on the evaluation of immune responses to different COVID-19 vaccines are limited. Similarly, effects of age and gender have not been well explored as variables that could impact on the vaccine-induced antibody response. Therefore, seroprevalence of anti-SARS-CoV-2 specific antibodies in vaccinated and vaccine naïve adult Nigerians was determined in this study. METHODOLOGY: A total of 141 adults were enrolled into this study. Presence or absence of SARS-CoV-2 infection was confirmed by real-time reverse-transcriptase polymerase-chain reaction (RT-PCR) assay on nasopharyngeal and oropharyngeal swab specimens. Anti-SARS-CoV-2 Specific IgG and IgM antibodies were qualitatively detected using a Rapid Diagnostic Test kit. RESULTS: Pre-vaccination, 77% of the study participants had never had PCR-confirmed COVID-19 test yet 66.7% of them were seropositive for SARS-CoV-2 antibodies. Of 111 COVID-19 vaccinated participants, 69.2% and 73.8% of them had SARS-CoV-2 specific IgG post-first and second doses of COVID-19 vaccine respectively. However, 23.1% and 21.4% of the participants who have had first and second doses respectively had no detectable anti-SARS-CoV-2 antibodies. The proportion of participants with SARS-CoV-2 specific IgG was insignificantly higher in those between the ages of 18-40 years and 41-59 years compared with individuals aged ≥60 years. No significant association was observed between gender and seropositivity for SARS-CoV-2 antibodies. CONCLUSION: There is high SARS-CoV-2 antibody seroprevalence among Nigerian adults who never had PCR-confirmed COVID-19. Also, there is the need for anti-SARS-CoV-2 antibodies screening post vaccination as this could be essential in achieving herd immunity. Age and gender do not seem to have significant association with seropositivity.


Asunto(s)
COVID-19 , Vacunas , Humanos , Adulto , Adolescente , Adulto Joven , Vacunas contra la COVID-19 , Estudios Seroepidemiológicos , SARS-CoV-2 , Anticuerpos Antivirales , Inmunoglobulina G , Reacción en Cadena en Tiempo Real de la Polimerasa
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