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1.
Foods ; 13(1)2023 Dec 29.
Article in English | MEDLINE | ID: mdl-38201151

ABSTRACT

Gabiroba, a native fruit in Brazil's Atlantic Forest region, has significant nutritional and therapeutic properties. However, due to its seasonality, consumption by the population is limited. Thus, the development of gabiroba byproducts would add significant value to the food and therapeutic industries. Therefore, it is essential to study and support the lack of toxicity of gabiroba fruit extracts. In the present study, physicochemical analyses of fresh fruits (GF) and dehydrated whole gabiroba flour (WGF) and preliminary toxicity analyses of WGF were performed. The toxicity results showed a microcrustacean LC50 of >1000 mg/mL when exposed to WGF extracts at various concentrations (10-1000 µg/mL; p = 0.062) using the Artemia salina method, with no evidence observed of proliferative activity or toxic metabolic compounds in the WGF extract. The phytotoxicity of WGF using Lactuca sativa L. allowed germination and root growth at various concentrations of WGF extract, with the lowest (100 µg/mL) and highest (1000 µg/mL) concentrations exhibiting 98.3% and 100% seed germination, respectively. In conclusion, these results indicate that the WGF preparation preserved the nutritional and antioxidant potential of gabiroba fruits and that WGF is safe for use as a raw material in the food industry and for therapeutic purposes.

2.
Chem Biodivers ; 19(11): e202200615, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36198078

ABSTRACT

Arctium lappa L., also known as burdock, is an edible wild plant which has the ability to grow in distinct environments and is considered a weed in several parts of the world. This species has great value in the biological and medical fields with its major secondary components being phenolic compounds and terpenes, substances rich in desired biological activities as antioxidant, antimicrobial, antitumor and anti-inflammatory. In addition, burdock leaves extracts have shown a modulatory effect on the complement system, which plays an important role in the development of inflammatory diseases, with an inhibitory effect on all complement pathways. Thus, natural products with those relevant activities are promising agents for healthcare applications. Therefore, the species A. lappa may represent an interesting asset for researching and developing new therapies for inflammatory afflictions.


Subject(s)
Arctium , Arctium/chemistry , Plant Extracts/chemistry , Antioxidants/chemistry , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/metabolism , Phytochemicals/pharmacology , Phytochemicals/metabolism
3.
Chem Biodivers ; 19(12): e202200568, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36259393

ABSTRACT

The species Euphorbia umbellata has been used to treat inflammatory diseases, cancer, and ulcers. Biological activities reported in the literature, including antiproliferative, cytotoxic and anti-inflammatory, are attributed to the chemical constituents present in its composition as terpenes and polyphenolic compounds. The most recurrently verified metabolites in the Euphorbiaceae family plant species are terpenes, of which euphol is a major constituent with broadly reported cytotoxic, antinociceptive and anti-inflammatory effects; it frequently appears in various extracts obtained from the plant. Euphol has a documented inhibitory effect on neutrophil chemotaxis and can modulate the complement system. Since complement system activation is intimately intertwined with autoimmune and inflammatory diseases, tumor growth promotion and metastasis, plant metabolites from Euphorbia umbellata might influence the outcomes of inflammatory processes. We believe that this is the first review presenting the current knowledge on Euphorbia umbellata secondary metabolites and their biological activities.


Subject(s)
Antineoplastic Agents , Euphorbia , Euphorbiaceae , Neoplasms , Humans , Euphorbia/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Lanosterol/pharmacology , Anti-Inflammatory Agents
4.
Immunol Invest ; 51(7): 2108-2121, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36166216

ABSTRACT

INTRODUCTION: Chagas disease (CD), caused by Trypanosoma cruzi, is a major public health issue worldwide affecting 6-7 million people, mainly in Latin America. The complement system plays a crucial role in host immune defense against T. cruzi infection and during the chronic phase of CD; however, the role of the MBL-associated serine protease 1 (MASP1) gene encoding MASP-1, MASP-3, and MAp44 complement proteins has not yet been reported in CD. This study investigated the possible association between MASP1 gene polymorphisms and MASP-3 protein serum levels in chronic CD and its clinical forms. METHODS: Five polymorphisms of MASP1 gene regulatory regions were genotyped in 214 patients with CD and 197 healthy controls (rs7609662 G>A, rs13064994 C>T, rs72549262 C>G, rs1109452 C>T and rs850314 G>A). MASP-3 serum levels were assessed in 70 patients and 66 healthy controls. Clinical data, serum levels of complement proteins (ficolin-2, ficolin-3 and MBL) and inflammatory markers (pentraxin-3 and hsCRP) were also included in the analyses. RESULTS: A significant association of the MASP1 GC_CCA haplotype with CD (padj= 0.002; OR 3.17 [1.19-8.39]) and chronic chagasic cardiomyopathy (CCC) (padj= 0.013; OR 4.57 [1.37-15.16] was observed. MASP-3 and pentraxin-3 levels were positively correlated in the patients (rho = 0.62; p = 0.0001). MASP-3 levels were not associated with MASP1 polymorphisms or CD and its clinical forms. Furthermore, no correlation was observed between MASP-3 levels and that of ficolin-2, ficolin-3, MBL and hsCRP. CONCLUSION: Our findings suggest a possible role for the MASP1 GC_CCA haplotype in susceptibility to chronic CD and CCC clinical forms.


Subject(s)
Chagas Disease , Mannose-Binding Protein-Associated Serine Proteases , C-Reactive Protein , Chagas Disease/genetics , Complement System Proteins , Humans , Mannose-Binding Protein-Associated Serine Proteases/genetics , Mannose-Binding Protein-Associated Serine Proteases/metabolism , Polymorphism, Genetic
5.
Life Sci ; 282: 119793, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34242658

ABSTRACT

Visceral leishmaniasis (VL) is a neglected and highly lethal disease. VL is endemic in South American countries, with Brazil being responsible for 96% of the cases. In this continent, VL is caused by the protozoan Leishmania (Leishmania) infantum (L. infantum), transmitted by the bite of infected female phlebotomine sandflies. Immediately after the inoculation of L.infantum promastigotes into the vertebrate host, the complement, as part of the first line of innate response, becomes activated. L. infantum promastigotes glycocalyx is rich in carbohydrates that can activate the lectin pathway of complement system. In this study, we evaluated whether the lectin pathway collectins [manose binding lectin (MBL) and collectin-11 (CL-11)] and ficolins (-1, -2 and -3) interact with L.infantum promastigotes, using confocal microscopy and flow cytometry. The binding of MBL, CL-11 and ficolins -1 and -3, but not ficolin-2, was observed on the surface of live metacyclic promastigotes after incubation with normal human serum (NHS) or recombinant proteins. C3 and C4 deposition as well as complement mediated lyses was also demonstrated after interaction with NHS. These results highlight a role for collectins and ficolins in the initial immune response to L.infantum.


Subject(s)
Complement System Proteins/immunology , Lectins/immunology , Leishmania infantum/immunology , Leishmaniasis, Visceral/immunology , Complement Activation , Host-Parasite Interactions , Humans , Leishmania infantum/physiology
6.
Immunol Invest ; 50(8): 1027-1041, 2021 Nov.
Article in English | MEDLINE | ID: mdl-32787514

ABSTRACT

The complement system is a key component of the innate immunity that plays a significant role in the development and clinical presentation of Rheumatoid arthritis (RA). Complement protein C3 is a central molecule in the activation of complement with a significant role in the inflammatory processes of RA. Nevertheless, the impact of C3 gene polymorphisms in the development of RA is still unknown. The current study aimed to investigate the possible influence of C3 gene polymorphisms in the susceptibility and clinical expression of RA. Three C3 polymorphisms (rs2250656:A > G, intron 2; rs2230199:C > G [p.Arg102Gly], exon 3 and rs1047286:C > T [p.Pro314Leu], exon 9) were assessed by sequence-specific PCR in a total of 156 RA patients and 270 healthy controls from Southern Brazil. In addition, C3 levels were measured in 60 patients and 60 controls by immunoturbidimetry and clinical features were collected from medical records. The frequency of rs2230199 G allele and GG genotype was significantly higher in RA patients than controls (padj = 0.012 OR = 1.57 [1.11-2.31]; padj = 0.008, OR = 1.60 [1.35-2.33]) as well as the rs1047286 T and TT (padj = 0.010, OR = 1.67 [1.12-2.40]; padj = 0.001, OR = 1.83 [1.27-2.65] and the C3 AGT haplotype (padj = 0.0007 OR = 1.92 [1.32-2.80]). Moreover, C3 serum levels were higher in patients than controls (median: 169 mg/dl vs.155 mg/dl; padj = 0.022), as well as in RF seronegative compared with seropositive patients (172 mg/dl vs. 165 mg/dl; padj = 0.007). Our results suggest that the rs2230199 G (p.102Gly) and rs1047286 T (p.314Leu) alleles play a role in the pathophysiology of RA, possibly impacting complement activation by the alternative pathway.


Subject(s)
Arthritis, Rheumatoid , Genetic Predisposition to Disease , Alleles , Arthritis, Rheumatoid/genetics , Case-Control Studies , Complement C3/genetics , Gene Frequency , Genotype , Humans , Polymorphism, Single Nucleotide
7.
Autoimmunity ; 53(7): 400-407, 2020 11.
Article in English | MEDLINE | ID: mdl-32820945

ABSTRACT

Rheumatoid arthritis (RA) is an autoimmune disease, which compromises the synovial membrane resulting in chronic inflammation. Ficolins are key proteins of the lectin pathway of complement able to recognize pathogen-associated molecular patterns, apoptotic cells, and cellular debris mediating the clearance by phagocytes. High ficolin-1 and ficolin-3 levels have been observed in RA patients, however, the influence of polymorphisms in the FCN1 gene in RA is not completely established, while no study evaluated FCN3 gene polymorphisms in RA to date. We investigated the influence of FCN1 and FCN3 gene polymorphisms in the susceptibility and clinical presentation of RA. A total of 148 patients with RA and up to 160 controls from Southern Brazil were genotyped by sequence-specific PCR (PCR-SSP) for five FCN1 promoter polymorphisms (rs2989727, rs10120023, rs17039495, rs10117466, and rs10858293) and three FCN3 gene variants (rs532781899, rs28362807, and rs4494157). The FCN1 g.-542GG (rs10120023) genotype and g.-542G allele, were associated with increased susceptibility to RA (p = .025, OR = 1.69 [1.07-2.69]; p = .041, OR = 1.47 [1.02-2.12], respectively) and related to decreased FCN1 gene expression in whole blood (p < .00001), according to gene expression databases. In addition, the FCN1 AAGAG haplotype was more prevalent in rheumatoid factor seronegative in comparison to seropositive patients (p = .006, OR = 0.042 [0.002-0.80]). There was no association of FCN3 polymorphisms with the susceptibility or clinical characteristics of RA. Our results indicate that the FCN1 rs10120023 [g.-542G>A] polymorphism in the promoter region might contribute to RA susceptibility, probably by impacting FCN1 gene expression.


Subject(s)
Arthritis, Rheumatoid/etiology , Genetic Predisposition to Disease , Lectins/genetics , Polymorphism, Single Nucleotide , Alleles , Arthritis, Rheumatoid/diagnosis , Arthritis, Rheumatoid/metabolism , Brazil , Complement System Proteins/immunology , Gene Expression , Genetic Association Studies , Genotype , Haplotypes , Humans , Promoter Regions, Genetic , Ficolins
8.
Front Immunol ; 11: 574457, 2020.
Article in English | MEDLINE | ID: mdl-33643280

ABSTRACT

Thousands of leprosy patients not only suffer from physical deformities, but also either have or have had hepatitis B virus (HBV) coinfection. Polymorphisms of the complement system modulate susceptibility to leprosy, but genetic susceptibility to past or present HBV infection is unknown. We used sequencing and multiplex sequence-specific PCR to genotype 72 polymorphisms of seven genes (MBL2, FCN1, FCN2, FCN3, MASP1, MASP2, C3) encoding components of the lectin pathway, and two genes encoding complement receptors (CR1, VSIG4) in 190 patients, of which 74 were positive for HBsAg and/or anti-HBc (HBV+, 93.2% with a resolved infection) and 116 lepromatous patients, and 408 HBV-blood donors. In addition, we tested for levels of proteins of the lectin pathway. We found no difference between serum concentrations of mannan-binding lectin (MBL), MBL-associated serine proteins (MASP-1, MASP-2, MASP-3, MAp44), ficolin-3 (FCN-3), soluble complement receptor 1 (sCR1) and MBL mediated C4 activation, measured by ELISA or TRIFMA in up to 167 HBV+ and HBV- patients. Haplotypes lowering protein levels or encoding dysfunctional proteins increased susceptibility to HBV infection: MBL2*LYQC (OR = 3.4, p = 0.02), MASP1*AC_CC (OR = 4.0, p = 0.015) and MASP2*1C2-l (OR = 5.4, p = 0.03). Conversely, FCN1*3C2 haplotype, associated with higher gene expression, was protective (OR = 0.56, P = 0.033). Other haplotypes associated with HBV susceptibility were: MASP2*2B1-i (OR = 19.25, P = 0.003), CR1*3A (OR = 2.65, P = 0.011) and VSIG4*TGGRCG (OR = 12.55, P = 0.014). Some polymorphisms in ficolin genes associated with lower protein levels increased susceptibility to leprosy/HBV infection: FCN*1 (OR = 1.66, P = 0.029), FCN2*GGGCAC (OR = 6.73, P = 0.008), and FCN3*del_del_C (OR = 12.54, P = 0.037), and to lepromatous disease/HBV infection: FCN2*TA (OR = 2.5, P = 0.009), whereas FCN2*MAG was associated with increased FCN-2 expression and resistance against coinfection (OR = 0.29, P = 0.026). These associations were independent of demographic factors and did not increase susceptibility to leprosy per se, except MASP2*1C2-l. Associations for FCN2, FCN3, MASP1, MASP2, and VSIG4 variants were also independent of each other. In conclusion, polymorphisms compromising activation of the lectin pathway of complement increase susceptibility to HBV infection, with ficolin polymorphisms playing a major role in modulating the susceptibility among leprosy patients.


Subject(s)
Coinfection/genetics , Complement Pathway, Mannose-Binding Lectin/genetics , Hepatitis B/genetics , Leprosy/genetics , Receptors, Complement/genetics , Adult , Aged , Aged, 80 and over , Coinfection/immunology , Complement System Proteins/genetics , Complement System Proteins/metabolism , Female , Genetic Association Studies , Genetic Predisposition to Disease/genetics , Genotype , Haplotypes , Hepatitis B/immunology , Hepatitis B virus , Humans , Leprosy/immunology , Male , Middle Aged , Mycobacterium leprae , Polymorphism, Single Nucleotide , Young Adult
9.
Immunol Lett ; 200: 18-25, 2018 08.
Article in English | MEDLINE | ID: mdl-29908956

ABSTRACT

BACKGROUND: Acute myocardial infarction (AMI) is a potentially fatal condition, being a major cause of death worldwide. Ischemia suffered during AMI causes tissue damage, leading to an inflammatory process. Moreover, myocardial injury can generate damage-associated molecular patterns that activate pattern recognition molecules including some complement proteins. METHODS: Here we investigated products of complement activation, C3d and soluble C5b9 (sC5b9), as potential biomarkers for myocardial injury and inflammation, as well as serum cytokines (IL-6 and TNF-alpha), alpha-1-acid glycoprotein (AGP), and classical markers of myocardial necrosis (creatine kinase, creatine kinase-MB isoform, myoglobin and troponin-I) in a longitudinal study of patients with AMI (from admission, 6 h and 12 h post admission, and at discharge from hospital). Individuals undergoing cardiac catheterization (CC) with normal coronary arteries and asymptomatics with no history of cardiovascular disease or invasive procedures were included as controls. RESULTS: Plasma C3d was higher in AMI at admission, 6 h, 12 h, and discharge vs CC (p < 0.0001; p = 0.0061; p = 0.0081; p = 0.044) and asymptomatic (p = 0.0001 for admission, 6 h and 12 h; p = 0.0002 for discharge). Moreover, sC5b9 was higher only at admission and 6 h vs asymptomatic (p = 0.0031 and p = 0.0019). Additionally, AGP levels were elevated at admission, 6 h, 12 h, and discharge vs asymptomatic (p = 0.0003; p = 0.0289; p = 0.0009, p = 0.0017). IL-6 concentration was low at admission and 6 h and reached a peak at 12 h (p < 0.0001 for all groups). All classical markers of myocardial necrosis presented higher concentration at 6 h. CONCLUSIONS: Our results showed that complement activation is an early event in AMI occurring before the elevation of classical markers of myocardial necrosis such as creatine kinase, creatine kinase-MB isoform, myoglobin and troponin-I. These findings indicated C3d and sC5b9 as possible biomarkers for inflammation and tissue damage in AMI.


Subject(s)
Complement Activation/immunology , Complement System Proteins/immunology , Complement System Proteins/metabolism , Myocardial Infarction/etiology , Myocardial Infarction/metabolism , Adult , Aged , Biomarkers , Case-Control Studies , Complement C3d/immunology , Complement C3d/metabolism , Complement Membrane Attack Complex/immunology , Complement Membrane Attack Complex/metabolism , Female , Humans , Inflammation , Male , Middle Aged , Models, Biological , Myocardial Infarction/diagnosis , Myocardial Infarction/therapy , Time Factors , Troponin I/blood
10.
PLoS Negl Trop Dis ; 11(2): e0005409, 2017 02.
Article in English | MEDLINE | ID: mdl-28241035

ABSTRACT

Leprosy is a chronic inflammatory disease caused by Mycobacterium leprae that mainly affects the skin and peripheral nervous system, leading to a high disability rate and social stigma. Previous studies have shown a contribution of genes encoding products of the lectin pathway of complement in the modulation of the susceptibility to leprosy; however, the ficolin-3/FCN3 gene impact on leprosy is currently unknown. The aim of the present study was to investigate if FCN3 polymorphisms (rs532781899: g.1637delC, rs28362807: g.3524_3532insTATTTGGCC and rs4494157: g.4473C>A) and ficolin-3 serum levels play a role in the susceptibility to leprosy. We genotyped up to 190 leprosy patients (being 114 (60%) lepromatous), and up to 245 controls with sequence-specific PCR. We also measured protein levels using ELISA in 61 leprosy and 73 controls. FCN3 polymorphisms were not associated with disease, but ficolin-3 levels were higher in patients with FCN3 *2B1 (CinsA) haplotype (p = 0.032). Median concentration of ficolin-3 was higher in leprosy per se (26034 ng/mL, p = 0.005) and lepromatous patients (28295 ng/mL, p = 0.016) than controls (18231 ng/mL). In addition, high ficolin-3 levels (>33362 ng/mL) were more common in leprosy per se (34.4%) and in lepromatous patients (35.5%) than controls (19.2%; p = 0.045 and p = 0.047, respectively). Our results lead us to suggest that polymorphisms in the FCN3 gene cooperate to increase ficolin-3 concentration and that it might contribute to leprosy susceptibility by favoring M. leprae infection.


Subject(s)
Genetic Predisposition to Disease , Glycoproteins/blood , Glycoproteins/genetics , Haplotypes , Lectins/blood , Lectins/genetics , Leprosy/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Middle Aged , Polymerase Chain Reaction , Polymorphism, Single Nucleotide , Serum/chemistry , Young Adult
11.
Int J Rheum Dis ; 19(10): 1024-1031, 2016 Oct.
Article in English | MEDLINE | ID: mdl-26250118

ABSTRACT

BACKGROUND: Leprosy patients may present several osteoarticular complaints, which require further evaluation of inflammatory diseases, such as rheumatoid arthritis (RA). Therefore, an adequate clinical assessment in addition to testing for rheumatoid factors (RF) and anticyclic citrullinated peptide antibodies (anti-CCP), can be useful in order to establish the correct diagnosis. METHOD: In this study, the relation of RF and anti-CCP with rheumatological manifestations was evaluated in 97 leprosy patients from Southern Brazil. The results were compared to RA patients and healthy controls from the same geographical area and ethnic background. RESULTS: Neuropathy was observed in 71.1% and arthritis in 35.1% of the leprosy patients. A high frequency of RF positivity was observed among the leprosy patients (41.2%, 40/97), with RF immunoglobulin A (IgA) significantly associated with arthritis (OR = 7.9, 95% CI = 1.5-40.6 P = 0.008). Anti-CCP was observed in 9.3% (9/97) of the patients, with anti-CCP2 being the most frequent subtype. Only 4.1% (4/97) of the patients were RF and anti-CCP concomitantly positive. RF IgM showed a significant association with leprosy when compared to healthy controls (P < 0.0001) whereas for anti-CCP2 no significant results were observed (P = 0.0585). However, both biomarkers showed a strong association with RA when compared to leprosy in patients from the same geographical area and ethnic background (anti-CCP2 OR = 38.6; 95% CI = 16.49-90.26; P < 0.0001 and RF IgM OR = 4.51; 95% CI = 2.62-7.77; P < 0.0001). CONCLUSION: Due to the similarity of some rheumatological manifestations in leprosy with other inflammatory diseases, such as RA, clinical and laboratorial evaluation of affected patients must be carefully assessed in order to achieve proper diagnosis and treatment.


Subject(s)
Arthritis, Rheumatoid/immunology , Immunoglobulin M/blood , Leprosy/immunology , Peptides, Cyclic/immunology , Rheumatoid Factor/blood , Adolescent , Adult , Aged , Aged, 80 and over , Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/diagnosis , Arthritis, Rheumatoid/ethnology , Biomarkers/blood , Brazil/epidemiology , Case-Control Studies , Female , Humans , Leprosy/blood , Leprosy/diagnosis , Leprosy/ethnology , Logistic Models , Male , Middle Aged , Odds Ratio , Predictive Value of Tests , Risk Factors , Young Adult
12.
Hum Immunol ; 75(12): 1197-202, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25318078

ABSTRACT

MASP-2 is a key protein of the lectin pathway of complement system. Several MASP2 polymorphisms were associated with MASP-2 serum levels or functional activity. Here we investigated a possible association between MASP2 polymorphisms and MASP-2 serum levels with the susceptibility to rheumatic fever (RF) and rheumatic heart disease (RHD). We haplotyped 11 MASP2 polymorphisms with multiplex sequence-specific PCR in 145 patients with history of RF from south Brazil (103 with RHD and 42 without cardiac lesion [RFo]) and 342 healthy controls. MASP-2 levels were determined by ELISA. The low MASP-2 producing p.377A and p.439H variants were negatively associated with RF (P=0.02, OR=0.36) and RHD (P=0.01, OR=0.25). In contrast, haplotypes that share the intron 9 - exon 12 g.1961795C, p.371D, p.377V and p.439R polymorphisms increased the susceptibility to RHD (P=0.02, OR=4.9). MASP-2 levels were associated with MASP2 haplotypes and were lower in patients (P<0.0001), which may reflect protein consumption due to complement activation. MASP2 gene polymorphisms and protein levels seem to play an important role in the development of RF and establishment of RHD.


Subject(s)
Mannose-Binding Protein-Associated Serine Proteases/genetics , Rheumatic Fever/genetics , Rheumatic Heart Disease/genetics , Adolescent , Adult , Base Sequence , Female , Gene Frequency , Genetic Predisposition to Disease , Haplotypes/genetics , Humans , Male , Mannose-Binding Protein-Associated Serine Proteases/metabolism , Middle Aged , Polymorphism, Single Nucleotide , Rheumatic Fever/blood , Rheumatic Heart Disease/blood , Sequence Analysis, DNA , Young Adult
13.
Front Pediatr ; 2: 148, 2014.
Article in English | MEDLINE | ID: mdl-25654073

ABSTRACT

The innate immune system is the first line of host defense against infection and is comprised of humoral and cellular mechanisms that recognize potential pathogens within minutes or hours of entry. The effector components of innate immunity include epithelial barriers, phagocytes, and natural killer cells, as well as cytokines and the complement system. Complement plays an important role in the immediate response against microorganisms, including Streptococcus sp. The lectin pathway is one of three pathways by which the complement system can be activated. This pathway is initiated by the binding of mannose-binding lectin (MBL), collectin 11 (CL-K1), and ficolins (Ficolin-1, Ficolin-2, and Ficolin-3) to microbial surface oligosaccharides and acetylated residues, respectively. Upon binding to target molecules, MBL, CL-K1, and ficolins form complexes with MBL-associated serine proteases 1 and 2 (MASP-1 and MASP-2), which cleave C4 and C2 forming the C3 convertase (C4b2a). Subsequent activation of complement cascade leads to opsonization, phagocytosis, and lysis of target microorganisms through the formation of the membrane-attack complex. In addition, activation of complement may induce several inflammatory effects, such as expression of adhesion molecules, chemotaxis and activation of leukocytes, release of reactive oxygen species, and secretion of cytokines and chemokines. In this chapter, we review the general aspects of the structure, function, and genetic polymorphism of lectin-pathway components and discuss most recent understanding on the role of the lectin pathway in the predisposition and clinical progression of Rheumatic Fever.

14.
PLoS One ; 8(7): e69054, 2013.
Article in English | MEDLINE | ID: mdl-23935922

ABSTRACT

BACKGROUND: The gene MASP2 (mannan-binding lectin (MBL)-associated serine protease 2) encodes two proteins, MASP-2 and MAp19 (MBL-associated protein of 19 kDa), bound in plasma to MBL and ficolins. The binding of MBL/MASP-2 and ficolin/MASP-2 complexes to microorganisms activates the lectin pathway of complement and may increase the ingestion of intracellular pathogens such as Mycobacterium leprae. METHODS: We haplotyped 11 MASP2 polymorphisms with multiplex sequence-specific PCR in 219 Brazilian leprosy patients (131 lepromatous, 29 borderline, 21 tuberculoid, 14 undetermined, 24 unspecified), 405 healthy Brazilians and 291 Danish blood donors with previously determined MASP-2 and MAp19 levels. We also evaluated MASP-2 levels in further 46 leprosy patients and 69 Brazilian controls. RESULTS: Two polymorphisms flanking exon 5 of MASP2 were associated with a dominant effect on high MASP-2 levels and an additive effect on low MAp19 levels. Patients presented lower MASP-2 levels (P = 0.0012) than controls. The frequency of the p.126L variant, associated with low MASP-2 levels (below 200 ng/mL), was higher in the patients (P = 0.0002, OR = 4.92), as was the frequency of genotypes with p.126L (P = 0.00006, OR = 5.96). The *1C2-l [AG] haplotype, which harbors p.126L and the deficiency-causing p.439H variant, has a dominant effect on the susceptibility to the disease (P = 0.007, OR = 4.15). Genotypes composed of the *2B1-i and/or *2B2A-i haplotypes, both associated with intermediate MASP-2 levels (200-600 ng/mL), were found to be protective against the disease (P = 0.0014, OR = 0.6). Low MASP-2 levels (P = 0.022), as well as corresponding genotypes with *1C2-l and/or *2A2-l but without *1B1-h or *1B2-h, were more frequent in the lepromatous than in other patients (P = 0.008, OR = 8.8). CONCLUSIONS: In contrast with MBL, low MASP-2 levels increase the susceptibility to leprosy in general and to lepromatous leprosy in particular. MASP2 genotypes and MASP-2 levels might thus be of prognostic value for leprosy progression.


Subject(s)
Exons , Genetic Predisposition to Disease , Haplotypes , Leprosy/genetics , Leprosy/metabolism , Mannose-Binding Protein-Associated Serine Proteases/genetics , Mannose-Binding Protein-Associated Serine Proteases/metabolism , Polymorphism, Genetic , Adolescent , Adult , Aged , Aged, 80 and over , Alleles , Brazil , Disease Progression , Female , Gene Frequency , Gene Order , Humans , Male , Middle Aged , Young Adult
15.
Microb Drug Resist ; 17(2): 313-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21417774

ABSTRACT

BACKGROUND: Scarce data are available about the antimicrobial resistance of Group A Streptococcus in South America. METHODS: This study evaluated the antimicrobial susceptibility profile of 1,112 isolates of Group A Streptococcus during the period from 1993 to 2009 in Curitiba city, Brazil. Macrolide-resistant isolates were characterized by emm typing and pulsed-field gel electrophoresis. RESULTS: All isolates were susceptible to penicillin, vancomycin, and tigecycline. On the contrary, 18.6% of the isolates were resistant to tetracycline, presenting a minimum inhibitory concentration (MIC)(50)/MIC(90) of 32/64 mg/L. Erythromycin resistance rose from 1.9% before 2000 to 4% after 2000 and was associated with a marked increased of MIC levels. Simultaneously, both the phenotype and genotype of macrolide resistance were modified as the M phenotypes (mef(A) genotype) were replaced by the cMLS(B) phenotypes (erm(B) genotype). CONCLUSION: This polyclonal spreading of cMLS(B) macrolide resistance has not been previously observed in South America and should stimulate further epidemiological surveillance in this part of the world.


Subject(s)
Body Fluids/microbiology , Drug Resistance, Bacterial/genetics , Macrolides/pharmacology , Respiratory System/microbiology , Streptococcal Infections/microbiology , Streptococcus/drug effects , Streptococcus/genetics , Adolescent , Adult , Anti-Bacterial Agents/pharmacology , Bacterial Typing Techniques , Brazil , Child , Child, Preschool , Drug Resistance, Bacterial/drug effects , Electrophoresis, Gel, Pulsed-Field , Female , Genotype , Humans , Infant , Longitudinal Studies , Male , Microbial Sensitivity Tests , Middle Aged , Phenotype , Population Surveillance , Streptococcal Infections/drug therapy , Streptococcal Infections/epidemiology , Streptococcal Infections/transmission , Streptococcus/classification , Streptococcus/isolation & purification
16.
Arch Dermatol Res ; 303(7): 521-5, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21327568

ABSTRACT

Pemphigus is characterized by circulating autoantibodies directed against desmossomal antigens that, once bound to target antigens, induce disruption in the cell-cell adhesion of the epidermis and mucosal epithelium, leading to blister formation. Evidence has indicated a role for complement in the physiopathology of pemphigus, with complement deposition in intercellular spaces of skin and mucous membrane lesions. Mannan-binding lectin (MBL) and Ficolin-2 are recognition proteins of innate immunity, which by binding to specific molecular patterns on pathogens surfaces trigger the activation of complement, leading to phagocytosis and lyses of target cells and inflammation. In this study we report for the first time the deposition of MBL and ficolins in pemphigus lesions. Eight biopsies of skin lesions of pemphigus vulgaris were studied for in situ deposition of IgG and the complement components MBL, Ficolin 1, Ficolin-2, C1q, C3 and membrane attack complex C5b-9. All biopsies presented deposition of IgG and C3 in the intercellular spaces (ICS) of epidermis. MBL deposition was found in the ICS and basal membrane zone (BMZ) of all specimens, whereas C5b-9 showed deposition only in the ICS, with irregular distribution. Ficolin-2 were positive in 50% (4/8) of biopsies showing deposition in the BMZ. On the other hand, ficolin-1 and C1q were negative in all specimens. Our study suggest that MBL and to a lesser extend Ficolin-2 may bind to altered intercellular structures in the skin and lead to the activation of complement in situ, contributing to tissue damage in pemphigus.


Subject(s)
Epithelium/metabolism , Lectins/metabolism , Mannose-Binding Lectin/metabolism , Pemphigus/immunology , Receptors, Pattern Recognition/metabolism , Antigen-Antibody Complex/metabolism , Autoantibodies/blood , Blister , Complement Activation , Complement System Proteins/metabolism , Epithelium/pathology , Humans , Immunity, Innate , Immunoglobulin G/metabolism , Intercellular Junctions/metabolism , Lectins/genetics , Mannose-Binding Lectin/genetics , Pemphigus/pathology , Pemphigus/physiopathology , Receptors, Pattern Recognition/genetics , Skin/pathology , Ficolins
17.
Digestion ; 83(1-2): 89-95, 2011.
Article in English | MEDLINE | ID: mdl-21042020

ABSTRACT

BACKGROUND/AIMS: In this study, a clinical and serological follow-up of 8-10 years was performed in relatives of celiac disease (CD) patients from southern Brazil. The occurrence of new CD cases in the families and the use of two different IgA-tTG enzyme-linked immunosorbent assay (ELISA) kits were also evaluated. METHODS: Serum samples of 233 relatives, 186 recruited between 1997 and 2000 (phase I) and 138 between 2006 and 2007 (phase II: 91 of the follow-up group and 47 newly tested), were analyzed. As a comparison group, 100 unrelated healthy individuals were evaluated. IgA-EmA was tested by indirect immunofluorescence and IgA-tTG by ELISA. RESULTS: A significant increase in IgA-EmA/IgA-tTG was detected in relatives of patients with CD when compared to controls (p ≤ 0.001). The positivity of antibodies was higher in females (2.4:1 in phase II; p = 0.039), and its high frequency amongst siblings (∼18.81%) highlights the risk of CD in these individuals. The distribution of antibodies by age suggested that CD can occur at any age in relatives, calling attention to the newly tested relatives >60 years of age (p = 0.0657). A better performance of ELISA kits with human tTG was observed. The confirmation of 13 biopsy-proven new CD cases (5.6%; 13/233) at present points out the predisposition to CD in these individuals and the high specificity of concurrently positive antibodies in relatives, especially when both are present in high titers. CONCLUSION: These results emphasize the familial risk to develop CD and the value of serological screening as an instrument for identifying this disease.


Subject(s)
Autoantibodies/blood , Celiac Disease/diagnosis , Enzyme-Linked Immunosorbent Assay , Adolescent , Adult , Aged , Aged, 80 and over , Brazil/epidemiology , Celiac Disease/epidemiology , Celiac Disease/immunology , Child , Child, Preschool , Family , Female , Humans , Immunoglobulin A/blood , Male , Middle Aged , Transglutaminases/immunology , Young Adult
18.
N Am J Med Sci ; 2(3): 138-42, 2010 Mar.
Article in English | MEDLINE | ID: mdl-22624128

ABSTRACT

BACKGROUND: Celiac disease has been described in populations from around the world, with recent data emphasizing the occurrence of the disease in ethnic minorities. There are only a few studies evaluating celiac disease in native Indians. AIMS: This study aimed to screen the anti-endomysial antibody (IgA-EmA) in Kaingang and Guarani Indians from southern Brazil, in order to establish a clinical serological evaluation of celiac disease in these individuals. MATERIAL AND METHODS: Serum samples from 321 individuals (125 male and 196 female; 4-86 years old) from Mangueirinha Indigenous Reserve, State of Parana, Brazil, and 180 non-Indigenous healthy individuals (62 male and 118 female; 2-81 years old) were analysed to the presence of anti-endomysial antibody class IgA by indirect immunofluorescence assay. Amongst the Indians, 158 were Kaingang, 98 Guarani and 65 of mixed race. Indians presenting complaints of diarrhea (N=12) were also evaluated to the IgG class of anti-endomisyal antibody. RESULTS: None of the individuals showed positive results either to IgA or IgG anti-endomysial antibodies. CONCLUSIONS: Although the results indicate an absence of celiac disease in Kaingang and Guarani Indians, the authors call attention to the importance of following up indigenous children or adults presenting gastrointestinal complaints or other symptoms related to the disease. Consideration should be given to the genetic background of these individuals, allied to the inter ethnic marriages and the changing habits or occupational activities, that have gradually introduced diseases previously not described in indigenous populations.

19.
Mol Immunol ; 45(14): 3827-31, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18602696

ABSTRACT

Rheumatic fever (RF) and its most severe sequela, chronic rheumatic heart disease (CRHD), are mediated by an abnormal immunological host response following a Streptococcus pyogenes oropharyngeal infection. Mannan-binding lectin (MBL), a collectin that activates complement, binds to N-acetylglucosamine, a molecule present on the streptococcus cell wall and on human heart valves. As high levels of MBL and MBL2 associated genotypes have previously been seen to be associated with CRHD, we investigated the association between MBL2 polymorphisms and the presence of acute carditis and arthritis in patients with a history of RF. Polymorphisms in exon 1 and in the X/Y promoter region of the MBL2 gene were determined by PCR-SSP in 149 patients with a history of RF and 147 controls. Genotypes associated with the high production of MBL (YA/YA and YA/XA) were more frequent in the patients with acute (26/35, 74%) and chronic carditis (79/107, 74%) when compared to the controls (79/147, 54%; OR 2.48, 95% CI 1.09-5.67, p=0.035 and OR 2.42, 95% CI 1.41-4.16, p=0.001, respectively). Logistic regression analysis showed that MBL levels >2,800 ng/ml increased the risk of CRHD (OR 2.91, 95% CI 1.41-6.03, p=0.003). Among the RF patients without cardiac sequela, YA/YA and YA/XA genotypes were significantly associated with acute carditis when compared to the patients without this clinical manifestation (26/28, 93% vs. 9/14, 64%, OR 7.22, 95% CI 1.18-43.98, p=0.031); on the other hand, arthritis was more frequently observed in those patients presenting MBL2 genotypes related to the low production of MBL (10/14, 71% vs. 10/28, 36%; p=0.048, OR 0.22, 95% CI 0.05-0.89). We concluded that MBL2 genotypes associated with the high production of MBL seem to be involved in the pathogenesis of rheumatic carditis and its progression to CRHD.


Subject(s)
Mannose-Binding Lectin/genetics , Myocarditis/genetics , Rheumatic Fever/genetics , Acute Disease , Adolescent , Adult , Aged , Case-Control Studies , Child , Chronic Disease , Exons , Female , Genotype , Humans , Male , Mannose-Binding Lectin/blood , Middle Aged , Polymorphism, Genetic , Promoter Regions, Genetic , Risk Factors
20.
Hum Immunol ; 69(1): 41-4, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18295674

ABSTRACT

In this study we investigated whether partial or total MASP-2 deficiencies resulting from Asp105Gly mutation are associated with rheumatic fever (RF) and chronic rheumatic heart disease (RHD). The Asp105Gly MASP2 mutation (D105G) was detected by polymerase chain reaction-restriction fragment length polymorphism in 148 patients (43 men and 105 women; mean age 39.1 +/- 14.4 years) with a history of RF, including 106 (73%) with RHD and 42 (27%) without cardiac sequelae, and 129 control subjects (52 men and 77 women, mean age 38.4 +/- 12.2 years). The D105G mutation was detected in four patients with RHD (3.77%) and in five control subjects (3.88%), all in the heterozygous state. None of the patients without cardiac sequelae had the mutation. No significant difference was found in the frequency of the mutant allele between the groups (p < 0.6). These results suggest that the D105G mutation in the MASP2 gene does not play a major role in the pathogenesis of RF. Whether D105G plays a role in the development of RHD should be ascertained in future studies.


Subject(s)
Mannose-Binding Protein-Associated Serine Proteases/genetics , Polymorphism, Genetic , Rheumatic Fever/genetics , Rheumatic Heart Disease/genetics , Adolescent , Adult , Aged , Amino Acid Substitution , Child , Chronic Disease , Female , Humans , Male , Middle Aged , Rheumatic Fever/diagnosis , Rheumatic Heart Disease/diagnosis
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