Evaluation of the Lectin Pathway in the Serum of Patients with Chronic Chagas Disease by Detection of C4 by Elisa / Avaliação da via das lectinas no soro de pacientes com doença de Chagas crônica pela detecção de C4 por Elisa

ABSTRACT Chagas disease (CD) is a chronic tropical disease caused by Trypanosoma cruzi , affecting about 8 million people in Latin America. The lectin pathway (LP) of the complement system is one of the first lines of host defense in the response against T. cruzi , and can continue to be activated in chronic infection due to the escape of the parasite to its action. Although some components of this pathway have been investigated in CD, there are no reports on its activation in patient serum. In this context, our objective was to evaluate the activation of LP in chronic chagasic patients and controls by the detection of the C4 component, using the direct ELISA assay. For this purpose, serum of 80 patient with chronic CD (clinical forms: asymptomatic n=17; symptomatic n=63; cardiac n=45; cardio digestive n=13; digestive n=5) followed at the Ambulatory of Attention to Chagasic Patients (HC/UFPR) and 80 healthy controls (donors of the Blood Bank of HC) were evaluated regarding the evaluation of the LP. The results showed that LP activation by mannose-binding lectin (MBL) was found reduced while activation by ficolins was increased in patients with CD when compared to controls. The same results were observed when the patients were categorized according to the indeterminate and symptomatic clinical forms. We conclude that the detection of the C4 component by ELISA is an efficient methodology to assess LP activation in serum from patients with chronic CD, enabling to differentiate the activation profile between patients and controls..

RESUMO A doença de Chagas (DC) é uma doença tropical crônica causada pelo Trypanosoma cruzi, atingindo cerca de 8 milhões de pessoas na América Latina. A via das lectinas (VL) do sistema complemento é uma das primeiras linhas de defesa na resposta imunológica contra a infecção pelo T. cruzi, e pode continuar sendo ativada na infecção crônicadevido ao escape do parasito à sua ação. Embora alguns componentes dessa via tenham sido investigados na DC, não existem relatos sobre sua ativação em soro de pacientes. Neste contexto, nosso objetivo foi avaliar a ativação da VL no soro de pacientes com DC crônica e controles pela detecção do componente C4 empregando a técnica de ELISA. Para isso, amostras de soro de 80 pacientes com DC crônica (formas clínicas: indeterminada n=17; sintomática n=63; cardíaca n=45; cardiodigestiva n=13; digestiva n=5) atendidos no Ambulatório de Atenção ao Paciente Chagásico (HC/UFPR) e 80 controles saudáveis (doadores do Banco de Sangue do HC) foram avaliados quanto a ativação da VL. Os resultados demonstraram que a ativação da VL pela lectina ligante de manose (MBL) encontra-se reduzida, enquanto que a ativação pelas ficolinas está aumentada em pacientes com DC quando comparados aos controles. Os mesmos resultados foram observados quando os pacientes foram categorizados quanto às formas clínicas indeterminada e sintomática. Concluímos que a detecção do componente C4 por ELISA é uma metodologia eficiente para avaliar a ativação da VL em soro de pacientes com DC crônica possibilitando diferenciar o perfil de ativação entre pacientes e controles.

Influence of the presence of mannose-binding lectin polymorphisms on the occurrence of leishmaniasis: a systematic review and meta-analysis

Abstract Background Leishmaniasis is caused by an intracellular protozoan of the Leishmania genus. Mannose-binding lectin (MBL) is a serum complement protein and recognizes lipoprotein antigens in protozoa and the bacterial plasma membrane. Nucleotide variants in the promoter region and exon 1 of the MBL gene can influence its expression or change its molecular structure. Objective To evaluate, through a systematic review, case-control studies of the genetic association of variants in the MBL2 gene and the risk of developing leishmaniasis. Methods This review carried out a search in PubMed, Science Direct, Cochrane Library, Scopus and Lilacs databases for case-control publications with six polymorphisms in the mannose-binding Lectin gene. The following strategy was used: P = Patients at risk of leishmaniasis; I = Presence of polymorphisms; C = Absence of polymorphisms; O = Occurrence of leishmaniasis. Four case/control studies consisting of 791 patients with leishmaniasis and 967 healthy subjects (Control) are included in this meta-analysis. The association of variants in the mannose-binding Lectin gene and leishmaniasis under the allelic genetic model, -550 (Hvs. L), -221 (X vs. Y), +4 (Q vs. P), CD52 (A vs. D), CD54 (A vs. B), CD57 (A vs. C) and A/O genotype (A vs. O) was evaluated. International Prospective Register of Systematic Reviews (PROSPERO): CRD42020201755. Results The meta-analysis results for any allelic genetic model showed no significant association for the variants within the promoter, the untranslated region, and exon 1, as well as for the wild-type A allele and mutant allele O with leishmaniasis. Study limitations Caution should be exercised when interpreting these results, as they are based on a few studies, which show divergent results when analyzed separately. Conclusions This meta-analysis showed a non-significant association between the rs11003125, rs7096206, rs7095891, rs5030737, rs1800450, and rs1800451 polymorphisms of the Mannose-binding Lectin gene and leishmaniasis in any allelic and heterogeneous evaluation.

Association of the polymorphism Exon 1 (A/O) region of the mannose-binding lectin gene and periportal fibrosis regression in schistosomiasis after specific treatment

Abstract INTRODUCTION: We evaluated the association between genetic polymorphisms in exon 1 (A/O alleles) and promoter regions at positions -550 (H/L variant, rs11003125) and -221 (X/Y variant, rs7096206) MBL2 and periportal fibrosis regression. METHODS: This was a retrospective cohort study involving 114 Brazilians infected with Schistosoma mansoni, who were subjected to follow-up for three years after specific treatment for schistosomiasis to estimate the probability of periportal fibrosis regression. RESULTS: A risk association was observed between polymorphism at the exon 1 MBL2 and periportal fibrosis regression. CONCLUSIONS: This study suggests that the polymorphism of exon 1 MBL2 may potentially be used to predict periportal fibrosis regression in this population.

Mannose-binding lectin gene polymorphism and its effect on short term outcomes in preterm infants / Polimorfismo do gene da lectina ligante de manose e seu efeito em desfechos de curto prazo em bebês prematuros

Abstract Objective: Mannose-binding lectin, which belongs to the collectin family, is an acute-phase reactant that activates the complement system. This study aimed to investigate the effect of MBL2 gene polymorphism on short-term outcomes in preterm infants. Method: Infants of <37 gestational weeks who were admitted to the neonatal intensive care unit during a two-year period were enrolled in this prospective study. The neonates were categorized into two groups according to their MBL2 genotypes. Normal MBL2 genotype was defined as MBL2 wild-type (AA genotype), whereas mutant MBL2 genotype was defined as MBL2 variant-type (AO/OO genotype). The relationship between MBL2 genotype and short-term morbidity and mortality was evaluated. Results: During the two-year study period, 116 preterm infants were enrolled in this study. In MBL2 variant-type, mannose-binding lectin levels were significantly lower and incidences of mannose-binding lectin deficiency (MBL level < 700 ng/mL) were higher (p < 0.001). In this group, the prevalence of respiratory distress syndrome and mortality was significantly higher (p < 0.001, p = 0.03 respectively). In the MBL2 wild-type group, the prevalence of necrotizing enterocolitis (NEC) was higher (p = 0.01). Logistic regression analyses revealed that MBL2 variant-type had a significant effect on respiratory distress syndrome development (odds ratio, 5.1; 95% confidence interval, 2.2-11.9; p < 0.001). Conclusions: MBL2 variant-type and mannose-binding lectin deficiency are important risk factors for respiratory distress syndrome development in preterm infants. Additionally, there is an association between MBL2 wild-type and NEC. Further studies on this subject are needed.

Resumo Objetivo: A lectina ligante de manose (MBL, do inglês mannose-binding lectin), que pertence à família das colectinas, é um reagente de fase aguda que ativa o sistema complemento. Este estudo teve como objetivo investigar o efeito do polimorfismo do gene MBL2 em desfechos de curto prazo em prematuros. Método: Este estudo prospectivo incluiu crianças com menos de 37 semanas de gestação admitidas na unidade de terapia intensiva neonatal durante dois anos. Os neonatos foram categorizados em dois grupos de acordo com os genótipos do MBL2. O genótipo normal do gene MBL2 foi definido como MBL2 do tipo selvagem (genótipo AA), enquanto o genótipo mutante do gene MBL2 foi definido como o gene variante (genótipo AO/OO). Foi avaliada a relação entre o genótipo MBL2 e a morbidade e mortalidade em curto prazo. Resultados: Durante o período de dois anos, 116 bebês prematuros foram incluídos neste estudo. Os níveis de lectina ligante de manose foram significativamente menores nos variantes do MBL2 e as incidências de deficiência de lectina ligante de manose (nível de MBL < 700 ng/mL) foram maiores (p < 0,001). Nesse grupo, a prevalência de síndrome do desconforto respiratório (SDR) e a mortalidade foram significativamente maiores (p < 0,001, p = 0,03, respectivamente). No grupo MBL2 do tipo selvagem, a prevalência de enterocolite necrosante foi maior (p = 0,01). Análises de regressão logística revelaram que os genes variantes do MBL2 apresentaram um efeito significativo no desenvolvimento da síndrome do desconforto respiratório (odds ratio, 5,1; intervalo de confiança de 95%, 2,2-11,9; p < 0,001). Conclusões: As variantes do MBL2 e a deficiência de lectina ligante de manose são importantes fatores de risco para o desenvolvimento da síndrome do desconforto respiratório em neonatos prematuros. Além disso, existe uma associação entre MBL2 do tipo selvagem e a enterocolite necrosante. Mais estudos são necessários sobre esse assunto.

Short Communication: Predicting receptor for mannose-binding lectin on neutrophil surface

Neutrophils play as major phagocytes that participate in the various effector phase of immunity. Mannosebinding lectin (MBL) assisted priming of neutrophils could trigger various processes including modulationof endocytosis rate, reactive oxygen production, chemotaxis, etc., through interactions with cell surfacereceptors. The physiological receptor for MBL on neutrophil's surface is still unreported. Macromoleculardocking could be attempted to determine the protein-protein interactions which are important forunderstanding cellular function and organization. The study was performed to identify the interacting partnerof MBL present on neutrophils surface which leads to the activation of various cell processes. Protein networkanalysis, homology modeling, and Rigid docking were performed to explore structural features and bindingmechanism of MBL with its cellular receptors. The results indicates that CR1 interact with the MBL and mayact as MBL receptor.

The value of the Luminex magnetic bead immunoassay in detecting serum MBL in kidney transplantation patients / 中华检验医学杂志

Objective@#To evaluate the performance of serum mannose-binding lectin(MBL) using Luminex magnetic bead immunoassay, and further clarify the value of serum MBL in the patients of renal transplantation.@*Methods@#A retrospective study based on 110 patients who had underwent renal transplantation in Peking University First Hospital from February 2012 to May 2016 was carried out, and 50 healthy persons were selected as controls. The precision, linearity and correlation of serum MBL were evaluated using Luminex magnetic bead immunoassay, and compared with the traditional ELISA method. The frequency of infection and clinical rejection after transplantation was evaluated according to serum pre-transplant MBL level before transplantation, based on the Luminex method. Statistics analysis was implemented with SPSS 19.0 and MedCalc 12.7.0 software.@*Results@#The repeatability precision and inter-day precision were less than 7.15% and 8.44% respectively, and linear range was 0.05-11 233.00 μg/L detected by Luminex immunoassay.The linear range of MBL detected by ELISA was 3.20-4 202.70 μg/L. The Luminex method had a wider range compared with ELISA. Correlation analysis showed that the regression equation was Y=1.248 6X+231.81, and the correlation coefficient was r=0.978 (P<0.01). Bland-Altman analysis showed that the average deviation percentage was 37.4% (95%CI 33.7%-41.1%).The median (quartile) of pre-transplant serum MBL was 4 164.00 (2 124.00, 7 064.50) μg/L. Patients with a serum MBL<4 164.00 μg/L and MBL≥4 164.00 μg/L were defined as low-and high-level group, respectively. The incidence of infection among the low-level group and high-level group was 47.4% (27/57) and 28.3% (15/53)respectively, which showed a statistical difference(χ2=4.230, P<0.05). The incidence of rejection among the low-level group and high-level group was 43.9% (25/57) and 20.8% (11/53)respectively, which also showed a statistical difference(χ2=6.659, P<0.05).@*Conclusions@#The Luminex magnetic bead immunoassay has a wider linearity compared with ELISA in detecting serum MBL. Additionally, serum pre-transplant MBL level has a good predictive value for the infection and rejection reaction after transplantation.

Correlation between gene polymorphism of mannose-binding lectin 2 and posttraumatic susceptibility to sepsis in Hainan Province / 中华创伤杂志

Objective@#To investigate the clinical relevance of mannose-binding lectin 2 (MBL2) gene polymorphism with traumatic sepsis in Hainan Province.@*Methods@#A retrospective case control study was conducted to analyze the clinical data of 112 severe trauma patients admitted to the First Affiliated Hospital of Hainan Medical College and Haikou People's Hospital from June 2017 to June 2018. There were 73 males and 39 females, aged 17-83 years [(41.8±8.9)years]. There were 48 patients in the sepsis group and 64 patients in the non-sepsis group. Multiplex single nucleotide extension polymorphism (SNaPshot) typing technique was used to detect the MBL2 gene polymorphism. The correlation between different genotypes and the risk of sepsis was analyzed. ELISA method was used to detect the level of MBL2 in plasma of each group.@*Results@#Among the three polymorphic loci of MBL2 gene (rs5030737, rs1800450 and rs1800451), the mutation frequency of rs1800450 was 27.7%, while the mutation frequency of rs5030737 and of rs1800451 was 0. The genotype distribution in two groups was in accordance with Hardy-Weinberg equilibrium. The frequency of GA genotype in sepsis group was significantly higher than that in non-sepsis group (P<0.05). A allele frequency in sepsis group was also much higher than that in non-sepsis group (P<0.05). Patients with GA genotype had increased risk of traumatic sepsis when compared to GG genotype(OR=3.442, 95%CI 1.447-8.187). Allele A increased the prevalence of sepsis significantly as well when compared to allele G(OR=2.799, 95%CI 1.270-6.170). The MBL2 level in serum in sepsis patients with genotype GG and GA was significantly lower than that in non-sepsis group (P<0.05). In sepsis group, the MBL2 serum level of patients with genotype GA was obviously lower than that in patients with genotype GG (P<0.05).@*Conclusion@#MBL2 rs1800450G/A polymorphism is closely related to the occurrence of sepsis in Hainan province, and may be related to the decrease of serum MBL2 level in patients with mutant type.

Correlation between gene polymorphism of mannose-binding lectin 2 and posttraumatic susceptibility to sepsis in Hainan Province / 中华创伤杂志

Objective To investigate the clinical relevance of mannose-binding lectin 2 (MBL2) gene polymorphism with traumatic sepsis in Hainan Province. Methods A retrospective case control study was conducted to analyze the clinical data of 112 severe trauma patients admitted to the First Affiliated Hospital of Hainan Medical College and Haikou People's Hospital from June 2017 to June 2018. There were 73 males and 39 females, aged 17-83 years [(41. 8 ± 8. 9)years]. There were 48 patients in the sepsis group and 64 patients in the non-sepsis group. Multiplex single nucleotide extension polymorphism ( SNaPshot ) typing technique was used to detect the MBL2 gene polymorphism. The correlation between different genotypes and the risk of sepsis was analyzed. ELISA method was used to detect the level of MBL2 in plasma of each group. Results Among the three polymorphic loci of MBL2 gene (rs5030737, rs1800450 and rs1800451), the mutation frequency of rs1800450 was 27. 7％, while the mutation frequency of rs5030737 and of rs1800451 was 0. The genotype distribution in two groups was in accordance with Hardy-Weinberg equilibrium. The frequency of GA genotype in sepsis group was significantly higher than that in non-sepsis group (P<0. 05). A allele frequency in sepsis group was also much higher than that in non-sepsis group (P<0. 05). Patients with GA genotype had increased risk of traumatic sepsis when compared to GG genotype(OR=3. 442, 95％CI 1. 447-8. 187). Allele A increased the prevalence of sepsis significantly as well when compared to allele G(OR =2. 799, 95％CI 1. 270-6. 170). The MBL2 level in serum in sepsis patients with genotype GG and GA was significantly lower than that in non-sepsis group (P<0. 05). In sepsis group, the MBL2 serum level of patients with genotype GA was obviously lower than that in patients with genotype GG (P<0. 05). Conclusion MBL2 rs1800450G/A polymorphism is closely related to the occurrence of sepsis in Hainan province, and may be related to the decrease of serum MBL2 level in patients with mutant type.

Relationship between serum mannose-binding lectin and Th17/Treg cells in patients with silicosis / 中国职业医学

OBJECTIVE: To explore the relationship between serum mannose-binding lectin( MBL) and T helper cell 17( Th17)/regulatory T cells( Treg) balance in patients with silicosis. METHODS: A total of 101 male patients with silicosis were selected in silicosis group and 62 health individuals in control group using the cross-sectional study. The level of serum MBL was measured by enzyme linked immunosorbent assay. The ratio of Th17/Treg was recorded by flow cytometry.The relative expression of retinoid-related orphan nuclear receptor γt( RORγt) and forkhead box 3( Foxp3) mRNA in peripheral blood mononuclear cell were tested by real-time polymerase chain reaction method. RESULTS: The level of serum MBL in silicosis group was higher than that of control group( P < 0. 01). The ratio of Th17 cells and the relative expression of RORγt mRNA increased in silicosis group( P < 0. 05),while the ratio of Treg cells and the relative expression of Foxp3 mRNA decreased in silicosis group( P < 0. 05) compared to the control group. The level of serum MBL had negative correlation with forced expiratory volume in the first second,forced vital capacity and forced expiratory flow( P < 0. 05) in patients with stage Ⅰ and Ⅱ silicosis. Meanwhile,the level of serum MBL had negative correlation with Th17 ratio and RORγt mRNA relative expression( P < 0. 05),and positive correlation with Treg ratio and Foxp3 mRNA relative expression( P < 0. 05). CONCLUSION: MBL might participate in the development of silicosis through regulating the balance of Th17/Treg cells.

Circulating levels of mannose-binding lectin (MBL) in age-related macular degeneration / Níveis circulantes da lectina ligadora de manose (MBL) na degeneração macular relacionada à idade

ABSTRACT Purpose: To assess whether the serum levels of mannose-binding lectin of the lectin complement pathway are associated with age-related macular degeneration. Methods: Patients with age-related macular degeneration and age-matched controls underwent full ophthalmologic examination and optical coherence tomography. Using a time-resolved immunofluorometric assay, blood samples were evaluated to determine the serum mannose-binding lectin levels. Results: A total of 136 individuals were evaluated, including 68 patients with age-related macular degeneration (34 exudative and 34 nonexudative) and 68 age-matched controls. The median mannose-binding lectin level was 608 ng/mL (range, 30-3,415 ng/mL) in patients with age-related macular degeneration and 739 ng/mL (range, 30-6,039 ng/mL) in controls, with no difference between the groups. Additionally, the median mannose-binding lectin level was 476 ng/mL (range, 30-3,415 ng/mL) in exudative cases and 692 ng/mL (range, 30-2,587 ng/mL) in nonexudative cases. Conclusions: Serum mannose-binding lectin levels were not associated with age-related macular degeneration or with the exudative and nonexudative forms of the disease.

RESUMO Objetivos: Avaliar se as concentrações séricas da lectina ligante de manose da via das lectinas do sistema complemento estão associadas à degeneração macular relacionada à idade. Métodos: Pacientes com degeneração macular relacionada à idade a controles pareados realizaram exame oftalmológico completo e imagens de tomografia de coerência óptica. As concentrações de lectina ligante de manose foram aferidas em amostras de sangue pelo método "time-resolved Immunofluorometric assay". Resultados: Um total de 136 indivíduos foram avaliados incluindo 68 com degeneração macular relacionada à idade (34 exsudativa e 34 não-exsudativa) e 68 controles. Concentrações medianas de lectina ligante de ma-nose foram 608 ng/mL (30-3,415 ng/mL) nos casos e 739 ng/mL (30-6,039 ng/mL) nos controles, não havendo diferença entre os grupos. Comparando degeneração macular relacionada a idade exsudativa (mediana de lectina ligante de manose 476 ng/mL; 30-3,415 ng/mL) e não-exsudativa (692 ng/mL; 30-2,587 ng/mL) também não apresentaram diferença. Conclusões: Concentrações séricas de lectina ligante de manose não estão relacionadas à degeneração macular relacionada a idade ou às formas exsudativa e não-exsudativa.

Serial Changes in Mannose-Binding Lectin in Patients with Sepsis / 결핵및호흡기질환

BACKGROUND: Mannose-binding lectin (MBL) deficiency leads to increased susceptibility to infection. We investigated whether serial changes in MBL levels are associated with the prognosis of patients diagnosed with septic shock, and correlated with cytokine levels. METHODS: We enrolled 131 patients with septic shock in the study. We analyzed the serum samples for MBL and cytokine levels at baseline and 7 days later. Samples on day 7 were available in 73 patients. RESULTS: We divided the patients with septic shock into four groups according to serum MBL levels ( < 1.3 µg/mL or ≥1.3 µg/mL) on days 1 and 7. Patients with low MBL levels on day 1 and high MBL levels on day 7 showed a favorable prognosis for 28-day survival (odds ratio, 1.96, 95% confidence interval, 1.10–2.87; p=0.087). The high MBL group on day 7 showed a significant decrease in monocyte chemoattractant protein 1, interleukin (IL)-1β, IL-6, IL-8, interferon-γ, and granulocyte macrophage colony-stimulating factor levels compared with the low MBL group on day 7. CONCLUSION: The increase in MBL levels of patients with septic shock may suggest a favorable prognosis and attenuate pro-inflammatory and anti-inflammatory responses.

The clinical relevance of MBL2 gene polymorphism and sepsis

Objective: To detect the clinical relevance of mannose-binding lectin 2 (MBL2) gene polymorphism and sepsis in Chinese lived in Hainan island. Methods: Blood samples from 57 patients with sepsis and 69 patients without sepsis were collected in the ICU of several large hospitals in Hainan province. Genomic DNA was extracted from whole blood and then PCR purification product was sequenced and typed by 3730 sequencing analyzer. The concentration of MBL2 in serum was detected by ELISA. Results: We found that genotype and allele distributions in two groups were in accordance with the Hardy-Weinberg Equilibrium. The frequency of GA genotype was significantly higher than that in non-sepsis group (P=0.013). A allele frequency in sepsis group was also much higher than that in non-sepsis group (P=0.028). Logister regression analysis showed that the patients who carried A allele were more prone to get sepsis than G allele carrier (P=0.014, 0R=2.550, 95%CI=1.207-5.386). The MBL2 level in serum of sepsis patients with genotype GG and GA was significantly lower than that in non-sepsis group (P<0.05). In sepsis group, the MBL2 serum level of patients with genotype GA was obviously lower than that in patients with genotype GG (P<0.05). Conclusions: The variation of rs1800450 G→A increased the incidence of sepsis and decreased the level of MBL2 in serum.

The clinical relevance of MBL2 gene polymorphism and sepsis

Objective:To detect the clinical relevance of mannose-binding lectin 2 (MBL2) gene polymorphism and sepsis in Chinese lived in Hainan island.Methods:Blood samples from 57 patients with sepsis and 69 patients without sepsis were collected in the ICU of several large hospitals in Hainan province. Genomic DNA was extracted from whole blood and then PCR purification product was sequenced and typed by 3730 sequencing analyzer. The concentration of MBL2 in serum was detected by ELISA.Results:We found that genotype and allele distributions in two groups were in accordance with the Hardy-Weinberg Equilibrium. The frequency of GA genotype was significantly higher than that in non-sepsis group (P=0.013). A allele frequency in sepsis group was also much higher than that in non-sepsis group (P=0.028). Logister regression analysis showed that the patients who carried A allele were more prone to get sepsis than G allele carrier (P=0.014, 0R=2.550, 95%CI=1.207-5.386). The MBL2 level in serum of sepsis patients with genotype GG and GA was significantly lower than that in non-sepsis group (P<0.05). In sepsis group, the MBL2 serum level of patients with genotype GA was obviously lower than that in patients with genotype GG (P<0.05).Conclusions:The variation of rs1800450 G→A increased the incidence of sepsis and decreased the level of MBL2 in serum.

Association of MBL With Work-Related Respiratory Symptoms in Bakery Workers

Baker's asthma is the most prevalent occupational asthma, and IgE-mediated response is known as a major pathogenesis. However, recent studies have suggested the involvement of innate immune response because wheat flour contains bacterial endotoxins or lipopolysaccharides. To further understand a role of innate immune response in the development of work-related respiratory symptoms (WRS) in bakery workers, we investigated mannose-binding lectin (MBL), one of the initiating components of the complement cascade in a single cohort of bakery workers. A total of 373 bakery workers completed a questionnaire regarding WRS. The bakery workers were divided into 2 groups according to previous history of allergic rhinitis (AR)/bronchial asthma (BA): those with history of AR/BA (group I) and those without (group II). We measured serum MBL levels by using enzyme-linked immunosorbant assay and genotyped 4 single nucleotide polymorphisms of the MBL2 gene (226G>A in exon 1, -554G>C, -431A>C, and -225G>C in the promoter) by using TaqMan assays. Fifty-nine subjects (15.5%) were previously diagnosed with AR/BA, and 64 subjects (16.8%) complained of WRS. No significant differences were found in serum MBL levels between groups I and II. However, in group II subjects, but not in group I subjects, the serum MBL levels were significantly higher in bakery workers with WRS than in those without. In addition, the serum MBL levels were significantly different according to genetic polymorphisms of the MBL2 gene and its haplotypes. In conclusion, serum MBL, affected by genetic polymorphisms, may be associated with WRS in bakery workers with no previous history of AR/BA.

Association of Single-Nucleotide Polymorphisms of the MBL2 with Atopic Dermatitis in Korean Patients

BACKGROUND: Human mannose-binding lectin (MBL) is a serum lectin taking part in the innate immunity by opsonizing various microorganisms for phagocytosis. The MBL serum concentration is affected by several single-nucleotide polymorphisms (SNPs) in the promoter region of the MBL2 gene. OBJECTIVE: The purpose of this study was to examine the relationship between MBL2 polymorphisms and atopic dermatitis (AD) susceptibility. METHODS: To examine whether the MBL2 SNPs are related to AD susceptibility, we examined 237 patients with AD and 94 controls by polymerase chain reaction (PCR)-restriction fragment length polymorphism and PCR-sequence specific primer analyses of four polymorphic loci: two (H/L and X/Y) within the promoter region and the other two (P/Q and A/B) within exon 1. MBL concentrations in the blood were estimated by ELISA. RESULTS: The prevalence of haplotype HYPB, leading to MBL deficiency, was significantly decreased in the AD patients compared to the controls (p=0.002), while the prevalence of haplotype HYPA was increased with a clear trend toward significance (p=0.056). The frequency of MBL2 LYPB/LXPA (odds ratio, 0.08; 95% confidence interval, 0.009~0.655; p=0.021) were significantly decreased in the AD patients. The blood log [total immunoglobulin E, IgE] levels of MBL2 HYPA/HYPA, HYPA/LYPA, HYPA/LYPB, HYPA/LYQA, and LYQA/LXPA haplotype pairs were significantly increased in the AD patients. CONCLUSION: The frequency of MBL2 HYPB haplotype was significantly decreased in the AD patients compared to the controls. The frequency of LYPB/LXPA had a possibly protective effect on AD. Moreover, the MBL2 HYPA haplotype pairs, which were related to higher blood total IgE levels, were possibly associated with extrinsic AD.

On vascular stenosis, restenosis and mannose binding lectin / Acerca de estenose vascular, re-estenose e lectina ligadora da manose

Mannose binding lectin is a lectin instrumental in the innate immunity. It recognizes carbohydrate patterns found on the surface of a large number of pathogenic micro-organisms, activating the complement system. However, this protein seems to increase the tissue damage after ischemia. In this paper is reviewed some aspects of harmful role of the mannose binding lectin in ischemia/reperfusion injury.

Lectina de ligação à manose é uma lectina instrumental na imunidade inata. Ela reconhece padrões de hidratos de carbono encontrados na superfície de um grande número de microrganismos patogênicos, que ativam o sistema complemento. No entanto, esta proteína parece aumentar o dano tecidual após isquemia. Neste trabalho são revisados alguns aspectos do papel nocivo da lectina de ligação à manose na lesão de isquemia/reperfusão.

The heredity of research in neonatal respiratory distress syndrome / 中国小儿急救医学

Neonatal respiratory distress syndrome(NRDS)is the most critical disease in neonatal pe-riod.Studies have proved that genetic factors play an important role in the pathogenesis of NRDS.More and more proteins and genes which are associated with NRDS are researched.This article mainly reviewed the re-search of surfactant protein,ATP-binding cassette transporters A3,mannose-binding lectin,thyroid transcrip-tion factor-1and NRDS.

Study on relation between regulation of MBL level and pulmonary tuberculosis susceptibility / 国际检验医学杂志

Objective To study the relation between the regulation of mannose‐binding lectin (MBL) level and pulmonary tuber‐culosis(TB) susceptibility .Methods A total of 142 inpatients with pulmonary TB and 120 healthy controls were recruited to par‐ticipate in this case‐control study .Serum MBL level was detected ,meanwhile the restriction fragment length polymorphism (RFLP) was adopted to detect MBL2 gene polymorphism .Results The one‐way analysis of variance was adopted to analyze the MBL level in different genotype groups ,including the group YA/YA ,XA/YA ,XA/XA ,YA/YB ,XA/YB and YB/YB ,it was found that the MBL level had statistical differences among 3 groups and between any two groups(P1 000 ng/mL ,while which in 100% individuals(26/26) carrying geno‐type XA/XA or allele B was≤1 000 ng/mL .Conclusion The MBL level may be associated with the susceptibility to pulmonary TB .The YA/YA gene for determining high MBL level may be a protected gene .

Effect of lectin (ScLL) on fibroblasts stimulated with LPS - an in vitro study

Abstract: The lectin (ScLL) extracted from the Synadenium carinatum plant has been evaluated as an immunomodulator in diseases such as asthma, neosporosis and leishmaniasis. However, it has not yet been evaluated in the oral cavity. This study evaluated the effect of ScLL on viability, proliferation and release of IL-10 in human gingival fibroblasts (HGF) stimulated with lipopolysaccharide (LPS). HGF were stimulated with LPS 1 µg/ml and treated with ScLL in concentrations of 10, 5 and 2 µg/ml for 1 and 5 h, and evaluated by flow cytometry for viability, apoptosis (initial/advanced) and necrosis. The supernatant was collected to detect release of IL-10 by ELISA. The proliferation was assessed with the BrdU assay. Positive control consisted of cells maintained in Dulbecco's Modified Eagles Medium (DMEM), and the negative control, of those kept in tap water. Data were analyzed by ANOVA and Dunnett's test (α = 0.05). No significant difference was found for ScLL concentrations regarding viability or initial and advanced apoptosis (p=0.455). All the groups, including the positive control, had a significantly lower necrosis parameter than negative control at 5 h (p < 0.001). No difference was found for proliferation among the experimental groups (p = 0.832). ScLL at 5 and 2 µg/ml resulted in a lower release of IL-10 than positive and negative controls at 5 h (p = 0.047). The results indicated that ScLL concentrations tested were not cytotoxic, and had no effect on proliferation and release of IL-10 parameters. A thorough understanding of ScLL, regarding its immunomodulatory potential, may open the door to new perspectives for dentistry.

Mannose-binding lectin 2 (Mbl2) gene polymorphisms are related to protein plasma levels, but not to heart disease and infection by Chlamydia

The presence of the single nucleotide polymorphisms in exon 1 of the mannose-binding lectin 2 (MBL2) gene was evaluated in a sample of 159 patients undergoing coronary artery bypass surgery (71 patients undergoing valve replacement surgery and 300 control subjects) to investigate a possible association between polymorphisms and heart disease with Chlamydia infection. The identification of the alleles B and D was performed using real time polymerase chain reaction (PCR) and of the allele C was accomplished through PCR assays followed by digestion with the restriction enzyme. The comparative analysis of allelic and genotypic frequencies between the three groups did not reveal any significant difference, even when related to previous Chlamydia infection. Variations in the MBL plasma levels were influenced by the presence of polymorphisms, being significantly higher in the group of cardiac patients, but without representing a risk for the disease. The results showed that despite MBL2 gene polymorphisms being associated with the protein plasma levels, the polymorphisms were not enough to predict the development of heart disease, regardless of infection with both species of Chlamydia.