RESUMO
Here, we performed single-cell RNA sequencing of S1 and receptor binding domain protein-specific B cells from convalescent COVID-19 patients with different clinical manifestations. This study aimed to evaluate the role and developmental pathway of atypical memory B cells (MBCs) in response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The results revealed a proinflammatory signature across B cell subsets associated with disease severity, as evidenced by the upregulation of genes such as GADD45B, MAP3K8, and NFKBIA in critical and severe individuals. Furthermore, the analysis of atypical MBCs suggested a developmental pathway similar to that of conventional MBCs through germinal centers, as indicated by the expression of several genes involved in germinal center processes, including CXCR4, CXCR5, BCL2, and MYC. Additionally, the upregulation of genes characteristic of the immune response in COVID-19, such as ZFP36 and DUSP1, suggested that the differentiation and activation of atypical MBCs may be influenced by exposure to SARS-CoV-2 and that these genes may contribute to the immune response for COVID-19 recovery. Our study contributes to a better understanding of atypical MBCs in COVID-19 and the role of other B cell subsets across different clinical manifestations.
Assuntos
COVID-19 , Células B de Memória , SARS-CoV-2 , Análise de Célula Única , Humanos , COVID-19/imunologia , COVID-19/virologia , COVID-19/genética , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Células B de Memória/imunologia , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Perfilação da Expressão Gênica , Transcriptoma , Centro Germinativo/imunologia , Linfócitos B/imunologia , IdosoRESUMO
This study reports the isolation and characterization of a human monoclonal antibody (mAb) called 19n01. This mAb was isolated by using single-cell RNAseq of B cells from donors infected with the ancestral strain. This mAb possesses a potent and broad capacity to bind and neutralize all previously circulating variants of concern (VOCs), including Omicron sublineages BA.1, BA.2, and BA.4/5. The pseudovirus neutralization assay revealed robust neutralization capacity against the G614 strain, BA.1, BA.2, and BA.4/5, with inhibitory concentration (IC50) values ranging from 0.0035 to 0.0164 µg/mL. The microneutralization assay using the G614 strain and VOCs demonstrated IC50 values of 0.013-0.267 µg/mL. Biophysical and structural analysis showed that 19n01 cross-competes with ACE2 binding to the receptor-binding domain (RBD) and the kinetic parameters confirmed the high affinity against the Omicron sublineages (KD of 61 and 30 nM for BA.2 and BA.4/5, respectively). These results suggest that the 19n01 is a remarkably potent and broadly reactive mAb.
RESUMO
The role of gut microbiota on immune regulation and the development of autoimmune diseases such as rheumatoid arthritis (RA) is an emerging research topic. Multiple studies have demonstrated alterations on gut microbiota composition and/or function (referred to as dysbiosis) both in early and established RA patients. Still, research delineating the molecular mechanisms by which gut microorganisms induce the loss of immune tolerance or contribute to disease progression is scarce. Available data indicate that gut microbiota alterations are involved in RA autoimmune response by several mechanisms including the post-translational modification of host proteins, molecular mimicry between bacterial and host epitopes, activation of immune system and polarization toward inflammatory phenotypes, as well as induction of intestinal permeability. Therefore, in this review we analyze recent clinical and molecular evidence linking gut microbiota with the etiopathogenesis of RA. The potential of the gut microbiota as a diagnostic or severity biomarker is discussed, as well as the opportunity areas for the development of complementary therapeutic strategies based on the modulation of gut microbiota in the rheumatic patient.
Assuntos
Artrite Reumatoide/patologia , Disbiose/complicações , Microbioma Gastrointestinal , Inflamação/complicações , Animais , Artrite Reumatoide/etiologia , HumanosRESUMO
CD36 glycoprotein is a candidate receptor involved in the gustatory detection of lipids and emerging evidence has suggested that genetic variations in CD36 may modulate the oral perception threshold to fatty acids. Here, we analyzed the association of -31118 G > A polymorphism in CD36 gene with nutritional status and preferences for fatty foods in Mexican children. Genotyping of SNP rs1761667 was performed in school-age children (n = 63) in addition to sensory tests evaluating the preference and satisfaction score assigned to oil-based sauces of different fatty acid composition. The G allele was associated with high BMI z-score in children (OR = 2.43, 95% (CI 1.02-5.99); p = 0.02) but CD36 genotypes (AA, GA, and GG) did not show significant association with the preference and satisfaction scores assigned to oil-based sauces. The BMI z-score showed no association with the preference to oil-based sauces; however, children with normal weight gave higher satisfaction scores to sauces with a high content of unsaturated fatty acids than to sauces rich in saturated fatty acids (0.56 ± 1.26 vs. 0.06 ± 1.22; p = 0.02). Therefore, the G allele of -31118 G > A SNP in CD36 gene is associated with overweight and obesity in Mexican children but do not appear to modulate the preferences and satisfaction scores to fat.
Assuntos
Gorduras na Dieta , Polimorfismo de Nucleotídeo Único , Antígenos CD36/genética , Criança , Genótipo , Humanos , ObesidadeRESUMO
BACKGROUND: Type 2 diabetes mellitus (T2D) is the most frequent type of diabetes. It has a multifactorial etiology, affecting millions of people worldwide. Ghrelin gene (GHRL) encodes the ghrelin peptide, which promotes food intake, induces body weight and adipogenesis. Several single nucleotide polymorphisms (SNPs) in GHRL gene have been associated with metabolic diseases. A protective effect of the Leu72Met (rs696217) polymorphism has been described for T2D in some populations, but this effect seems to depend on the ethnicity of the patients studied. METHODS: The aim of this study was to investigate the association between the GHRL Leu72Met (rs696217) SNP with the development of T2D and serum ghrelin levels in a Western Mexican population. We performed a case-control study in which we included 284 subjects (159 with previous T2D diagnosis and 125 control subjects (CS)). Leu72Met SNP was genotyped by using PCR-RFLPs technique. Serum ghrelin levels were measured using a commercial enzyme immunoassay. Genotypic and allelic distributions were compared using Chi square test. Student T-test and Mann-Whitney U test were used to compare quantitative variables. Odds ratio (OR) was used to evaluate the association between alleles or genotypes and T2D. Multiple and logistic regression models were performed for adjustment. A two-tailed p-value ≤0.05 was considered statistically significant. RESULTS: Leu72Leu genotype was more frequent among T2D compared to CS (p < 0.05). After adjusting for age and body composition, there was a significant protective effect of the 72Met allele for T2D development (OR 0.40 IC 95% 0.23-0.70; p ≤ 0.001). Fasting serum ghrelin levels were lower in T2D than CS (p ≤ 0.0001) irrespective of age, body weight and BMI. No associations were found between genotypes and ghrelin serum levels in our population. CONCLUSIONS: The GHRL 72Met allele decreases susceptibility for T2D development in a Western Mexican population. Serum ghrelin levels are lower in T2D independently of Leu72Met polymorphism genotype.
Assuntos
Biomarcadores/análise , Diabetes Mellitus Tipo 2/prevenção & controle , Predisposição Genética para Doença , Grelina/genética , Polimorfismo de Nucleotídeo Único , Adulto , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Feminino , Seguimentos , Genótipo , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , PrognósticoRESUMO
Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease characterized by elevated levels of pro-inflammatory cytokines, such as interleukin (IL)-6, IL-17, and macrophage migration inhibitory factor (MIF). MIF induces IL-17 secretion and MIF promoter polymorphisms influence the expression of selected downstream mediators. The aim of this study was to investigate the relationship between known functional MIF haplotypes and Th17-related cytokine secretion profile in peripheral blood mononuclear cells (PBMC) from control subjects (CS) and RA patients stimulated with lipopolysaccharide (LPS) and recombinant human MIF (rhMIF). The -794 CATT5-8 and -173Gâ¯>â¯C polymorphisms of the MIF gene were determined by conventional PCR and PCR-RFLP, respectively. The most frequent haplotypes of the MIF polymorphism and PBMC were identified from three subjects homozygous for each haplotype and in both study groups, the PBMC were obtained and stimulated with LPS or rhMIF. The secretion of cytokines related to the Th17 profile was determined by a multiplex immunoassay (MAGPIX). LPS stimulation induced the secretion of cytokines related to the Th17 profile in PBMC from CS and RA patients, whereas, rhMIF only stimulated this response in PBMC from RA patients. PBMC from CS carriers of the MIF 7C haplotype showed more IL-17A, IL-17F, IL-22, and IL-23 secretion than non-7C carriers after LPS stimulation. In the case of rhMIF stimulation, the PBMC from CS carriers of the 7C haplotype secreted more IL-17A and IL-23 than non-7C carriers. In conclusion, genetic variants of the MIF promoter modulate the secretion of cytokines related to the Th17 profile in PBMC from CS inducing a differential response in comparison to PBMC from RA patients.
Assuntos
Artrite Reumatoide/genética , Citocinas/genética , Haplótipos/genética , Oxirredutases Intramoleculares/genética , Leucócitos Mononucleares/metabolismo , Fatores Inibidores da Migração de Macrófagos/genética , Regiões Promotoras Genéticas/genética , Células Th17/metabolismo , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genéticaRESUMO
INTRODUCTION: Patients with HIV+ often present lipid disturbances. The role of ghrelin and obestatin in these lipid disturbances is not clear. The effect of antiretroviral (ART) drugs on those molecules is also unknown. This study measured ghrelin and obestatin levels, as well as metabolic markers, in patients with HIV+ before and after 36 weeks of ART. MATERIAL AND METHODS: Twenty HIV-positive, ART-naïve patients who started a scheme consisting of tenofovir/emtricitabine+lopinavir/ritonavir were enrolled. Plasma samples were collected before and after 36 weeks of treatment. Serum ghrelin and obestatin levels were quantitated by ELISA; glucose, cholesterol, and triglyceride levels were measured by colorimetric and enzymatic methods, and cardiovascular risk was calculated by the atherogenic index of plasma (AIP). RESULTS: All patients completed 36 weeks of ART. Total cholesterol (p<0.001), LDL-C (p=0.019), HDL-C (p=0.003), VLDL-C (p=0.002), and triglyceride levels (p=0.021) significantly increased after treatment. AIP revealed increased cardiovascular risk at baseline, which remained high after treatment. There was a statistically significant increase in obestatin level in the unpaired and paired analyses, while ghrelin levels only showed a trend to increase. Changes in ghrelin and obestatin levels positively correlated, but no correlation was seen with any metabolic parameter. CONCLUSION: After 36 weeks of ART, patients showed an altered lipid profile, but there were no significant changes in cardiovascular risk. Ghrelin and obestatin levels increased after 36 weeks of ART, but the increase was only significant for obestatin. Changes in ghrelin and obestatin positively correlate.
Assuntos
Antirretrovirais/farmacologia , Antirretrovirais/uso terapêutico , Grelina/sangue , Grelina/efeitos dos fármacos , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de TempoRESUMO
BACKGROUND AND OBJECTIVE: Lipid metabolism alterations contribute to acute coronary syndrome (ACS). rs670, rs5070 and rs693 polymorphisms have shown to modify the risk of cardiovascular disease. Apolipoprotein A-I (ApoA-I) plays a major role in reverse cholesterol transport; apolipoprotein B (ApoB) contributes to accumulation of cholesterol in the plaque. The aim of this study was to investigate the association of rs670 and rs5070 polymorphisms of APOA1 and rs693 polymorphism of APOB with ACS and circulating levels of its proteins and find if ApoB/ApoA-I could be implemented as an independent parameter of risk for cardiovascular disease and as a biomarker of lipid-lowering therapy effectiveness in Mexican population. METHODS: Three hundred patients with ACS and 300 control subjects (CS) were included. RESULTS: Neither genotype nor allele frequencies of rs670, rs5070 and rs693 polymorphisms showed statistical differences between groups. Serum levels of ApoA-I (195 vs. 161.4mg/dL; P<.001) and ApoB (167 vs. 136.9mg/dL; P<.001) were significantly higher in CS compared with ACS; however, there was no genetic association. Unstable angina patients showed the highest ApoA-I levels (males: 176.3mg/dL; females: 209.1mg/dL). CONCLUSION: The rs670, rs5070 and rs693 polymorphisms are not genetic susceptibility factors for ACS in Mexican population and had no effect on their apolipoprotein concentrations. In our population, ApoA-I, ApoB and HDL-C could be better biomarkers of cardiovascular risk and could indicate if statins doses reduce atherogenic particles properly.
Assuntos
Síndrome Coronariana Aguda/genética , Apolipoproteína A-I/genética , Apolipoproteína B-100/genética , Polimorfismo de Nucleotídeo Único , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Apolipoproteína A-I/sangue , Apolipoproteína B-100/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos Transversais , Feminino , Frequência do Gene , Marcadores Genéticos , Predisposição Genética para Doença , Genótipo , Humanos , Hipolipemiantes/uso terapêutico , Masculino , México , Pessoa de Meia-Idade , Fatores de Risco , Resultado do TratamentoRESUMO
Obesity is a metabolic disorder that has a multifactorial etiology and affects millions of people worldwide. Ghrelin, a hormone coded by the GHRL gene, plays a role in human body composition and appetite. Single nucleotide polymorphisms (SNPs) of the GHRL gene have been associated with obesity and metabolic disorders. To evaluate the association of A-604G SNP of GHRL promoter region with serum ghrelin levels and the risk of obesity in a Mexican population. Two hundred and fifty individuals were enrolled and classified as obese or control subjects (CS) according to BMI. DNA samples, anthropometric measurements and biochemical parameters were obtained from all subjects. The A-604G SNP was genotyped using PCR-RFLPs technique. Ghrelin levels were measured using a commercial enzyme immunoassay. The G/G genotype was more frequent among obese individuals (p < 0.0001) when compared to CS. The G/A genotype and A allele were associated with protection against obesity (OR 0.29, p < 0.0001; OR 0.39, p < 0.0001 respectively), the A allele remained significant after adjusting for age and gender (OR: 0.25, p < 0.0001). Serum ghrelin levels were higher in obese patients (p = 0.004) than in CS, however, significance was lost after adjustment for age (p = 0.088). The G/G genotype was associated with higher levels of serum ghrelin (p = 0.02) independently of the effect of age. The G/G genotype of the A-604G SNP in the GHRL gene is associated with altered serum ghrelin levels and obesity. The A allele was also associated with protection against obesity in this study.
Assuntos
Predisposição Genética para Doença , Grelina/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Feminino , Grelina/sangue , Humanos , Masculino , México , Pessoa de Meia-Idade , Obesidade/sangueRESUMO
Plasmablastic lymphoma is an aggressive variant of large B-cells lymphoma in which the infection by Human Immunodeficiency Virus and Epstein-Barr herpesvirus are involved. This recently denominated neoplasia has a special tropism through the oral cavity. However, its presence has been reported in the digestive tract, abdominal cavity and retroperitoneum. We describe two Human Immunodeficiency Virus infected patient cases with rectal presentation of PL in the HIV service of the Hospital Civil de Guadalajara.
RESUMO
Rheumatoid arthritis (RA) is an inflammatory autoimmune disease of unknown etiology. Many cytokines have been found to be associated with RA pathogenesis and among them is macrophage migration inhibitory factor (MIF). The aim of this study was to determine whether MIF serum levels are associated with RA course, clinical activity, and clinical biomarkers of the disease. MIF levels were determined in serum samples of 54 RA patients and 78 healthy subjects (HS) by enzyme-linked immunosorbent assay (ELISA). Disease activity was evaluated using the DAS28 score. Patients were subgrouped according to disease activity and years of evolution of disease. Statistical analysis was carried out by SPSS 10.0 and GraphPad Prism 5 software. RA patients presented increased levels of MIF as compared to HS. MIF levels were raised on early stages of RA and tend to decrease according to years of evolution. Moreover, MIF levels positively correlated with rheumatoid factor in RA patients and with C reactive protein in all individuals studied. Our findings suggest that MIF plays a role in early stages of RA.
Assuntos
Artrite Reumatoide/sangue , Oxirredutases Intramoleculares/sangue , Fatores Inibidores da Migração de Macrófagos/sangue , Adulto , Idoso , Antirreumáticos/uso terapêutico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Biomarcadores/sangue , Proteína C-Reativa/análise , Estudos de Casos e Controles , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Prognóstico , Fator Reumatoide/sangue , Índice de Gravidade de Doença , Regulação para Cima , Adulto JovemRESUMO
CD28 is one of the main activator receptors involved in systemic lupus erythematosus (SLE) pathogenesis, and its expression and serum levels are significantly higher in patients with SLE and other autoimmune diseases than in healthy controls (HC). However, it is unknown whether this increase is associated with specific organ damage. Therefore, our objective was to measure the CD28 levels in serum from SLE and HC groups to confirm the CD28 serum levels increase, as reported previously, and to determine whether this increase was associated with specific organ activity and the SLE Disease Activity Index (SLEDAI). Forty SLE patients and 40 matched HC were included, and the age, disease duration, SLEDAI and Mexican SLEDAI were recorded for the SLE group. CD28 serum levels were measured by ELISA. There was a statistically significant increase in the CD28 serum levels of SLE patients compared to controls (p = 0.039); however, we did not find any significant correlation with disease activity indices or organ involvement, although we found a significant but low correlation with C3. Our results and a review of the literature suggest that the increase in CD28 serum levels may be the result of CD28 gene overexpression, which could be related to the decrease in CD28+ T cells, T-cell hyporesponsiveness and immune impairment that occurs in SLE.
Assuntos
Antígenos CD28/sangue , Lúpus Eritematoso Sistêmico/imunologia , Regulação para Cima/imunologia , Adolescente , Adulto , Antígenos CD28/genética , Feminino , Humanos , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/patologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Linfócitos T/imunologia , Linfócitos T/patologia , Adulto JovemRESUMO
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by the presence of autoantibodies against nuclear autoantigens as well as cytoplasmic and circulating proteins. Recent studies have demonstrated mechanisms responsible for modulation of the immune response by the plasminogen activator inhibitor-1 (PAI-1). Furthermore, the endogenous PAI-1 has shown to promote a Th2 immune response. We assessed the -844 G>A and HindIII C>G PAI-1 polymorphisms in SLE. In a case-control study of 71 SLE patients classified according to ACR criteria and 71 healthy subjects (HS). The A allele of -844 PAI-1 polymorphism showed a significant difference in SLE patients (41%) when compared with HS (27%) [P = 0.01; OR = 1.8, 95%, CI = 1.1-3.0]. In addition, the -844 G>A PAI-1 polymorphism was associated with increased risk for SLE in a dominant genetic model (G/G vs. G/A + A/A; OR = 2.3, 95% CI = 1.14-4.44). Also, anti-RNP positive antibodies in SLE were associated with G/G -844 PAI-1 genotype. The HindIII polymorphism did not show any differences. The haplotype analysis showed that the AC haplotype confers susceptibility to SLE (OR = 3.1, 95% CI, 1.45-6.52; P = 0.003). The AC haplotype of the -844 and HindIII PAI-1 polymorphism might be an additional susceptibility factor to SLE in Mexicans.