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Rheumatic fever (RF) and chronic rheumatic heart disease (RHD) are complications of oropharyngeal infection caused by Streptococcus pyogenes. Despite the importance of the complement system against infections and autoimmunity diseases, studies on the role of the lectin pathway in RF and RHD are scarce. Thus, our aim was to evaluate the association of ficolin-3 serum levels, FCN3 polymorphisms and haplotypes with the susceptibility to RF and RHD. We investigated 179 patients with a history of RF (126 RHD and 53 RF only) and 170 healthy blood donors as control group. Ficolin-3 serum concentrations were measured using enzyme-linked immunosorbent assay (ELISA). Three FCN3 single nucleotide polymorphisms (SNPs rs532781899, rs28362807 and rs4494157) were genotyped through the sequence-specific PCR method. Lower ficolin-3 serum levels were observed in RF patients when compared to controls (12.81 μg/mL vs. 18.14 μg/mL respectively, p 0.0001, OR 1.22 [1.12-1.34]), and in RHD in comparison to RF only (RFo) (12.72 μg/mL vs. 14.29 μg/mL respectively, p = 0.016, OR 1.38 [1.06-1.80]). Low ficolin-3 levels (10.7 μg/mL) were more common in patients (39.5 %, 30/76) than controls (20.6 %, 13/63, p = 0.018, OR = 2.51 [1.14-5.31]), and in RHD (44.4 %, 28/63) than RFo (15.4 %, 2/13, p = 0.007, OR = 3.08 [1.43-6.79]). On the other hand, FCN3 polymorphism/haplotypes were not associated with ficolin-3 serum levels or the disease. Low ficolin-3 levels might be associated with RF, being a potential marker of disease progression.

Diabetes patients present a complex healing process due to several factors directly linked to their pathology. The use of medicinal plants that aid in tissue repair can bring great benefits to such individuals. This case report describes how the topical application of the aqueous extract produced from the leaves of Piper amalago L. was used to aid the healing of a lacerated wound in the left thumb of a patient with type 2 diabetes mellitus. The aqueous extract of the leaves of Piper amalago L. was prepared in boiling water. During the boiling process the dried leaves were submerged in the boiling water and left for five min. The injured thumb was submerged in the solution and the leaves were placed on the injury. The action of the aqueous extract obtained from the leaves of P. amalago was shown to be promising in the healing of a wound in a patient with type 2 diabetes mellitus. The topical application of the aqueous extract produced from the leaves of P. amalago assisted in the healing of a lacerated wound in the left thumb of a patient with type 2 diabetes mellitus over a period of 15 days.

The complement receptor of the immunoglobulin superfamily (CRIg, encoded by the VSIG4 gene) is a macrophage receptor involved in the clearance of immune complexes and autologous cells. Our results suggest that the VSIG4 rs1044165T allele is a risk factor for severe functional status of rheumatoid arthritis in women, possibly by affecting VSIG4 gene expression.

Ankylosing spondylitis (AS) patients may have higher prevalence of mannose-binding lectin (MBL) deficiency than normal individuals. MBL deficiency may influence susceptibility to infections. The aim of the study was to verify if MBL deficiency in patients with AS predisposes to infections. We studied 60 patients with AS diagnosed according to the Assessment of SpondyloArthritis international Society (ASAS) criteria. These patients had their MBL serum levels determinated. Twenty-five individuals were identified as MBL deficient (serum values 100 ng/mL). These patients were paired with 35 "sufficient" MBL producers (median serum level = 700 ng/mL; range 150-4100 ng/mL) for gender, age, use of medications, and tobacco exposure. Medical records of all patients were retrospectively investigated for the period of 5 years and the rate of infection occurrence was compared in the two groups. AS patients with MBL deficiency had higher number of urinary tract infections (p = 0.03; IRR = 2.33; 95% CI = 0.95-6.04) and tuberculosis (p = 0.008; IRR = 9.8; 95% CI = 1.2-441.6) than controls. Regarding tuberculosis infection, one patient (2.8%) in the MBL-sufficient group and six (24.0%) from the deficient group had this infection. The MBL-sufficient patient and five from the deficient group have had latent infections, detected in the screening tests done previous to anti-TNF drug use. The other, in the deficient group, had lung infection while not on anti-TNF treatment. Another patient, from the deficient group, has had tuberculosis skeletal infection in the past. We found a significant association between MBL deficiency and higher risk of tuberculosis and urinary tract infection in patients with AS. More studies with higher number of patients are needed to confirm this finding.

Objective: To evaluate serum concentrations of mannose-binding lectin (MBL) in women presenting with different human papillomavirus (HPV)-associated cervical lesions. Subjects and Methods: A total of 364 women, who underwent screening for cervical cancer or treatment at the Erasto Gaertner Cancer Hospital (HEG), Curitiba, Brazil, were enrolled in the study. Based on the latest cervical colposcopy-guided biopsy results, the women were divided into 4 groups: cervical intraepithelial neoplasia CIN-I (n = 54), CIN-II (n = 72), CIN-III (n = 145), and invasive cancer (n = 93). A time-resolved immunofluorometric assay was used to measure the MBL concentrations in serum. The statistical analysis was done using GraphPad Prism 6.0. Comparisons were performed by Kruskal-Wallis and Mann-Whitney tests and analyzed by χ2 test; continuous variables are presented as medians and categorical variables as frequencies. Results: The median MBL concentrations in decreasing order were as follows: invasive cancer: 1,452 ng/mL, CIN-I: 1,324 ng/mL, CIN-II: 1,104 ng/mL, and CIN-III 1,098 ng/mL. However, no statistical significance was found among the 4 groups with HPV-associated lesions (p = 0.11). Equally, the MBL levels did not show a significant association between the age of the patients and the severity of the cervical lesions (p = 0.68). No statistical significance was found in the median values of MBL or in the status of MBL deficient (1,000 ng/mL) among the women in each group (p = 0.77). Conclusion: In this study, there was no statistically significant difference in MBL serum levels among the groups with CIN. Hence MBL serum concentration appeared not to have influenced the progression of HPV-related preinvasive cervical lesions into invasive cancer.

Infections are usually involved in the pathogenesis of spondyloarthritis (SpA). Mannose-binding lectin (MBL) is a component of the innate immune system with an important role in microbial defense.To study the prevalence of MBL deficiency in SpA patients as well as its influence in the clinical profile of these diseases.We studied 89 SpA patients and 89 healthy individuals, paired for age and gender. MBL serum levels were measured by ELISA test. Individuals with levels ≤100 ng/mL were considered deficient. SpA patients had determination of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS)-CRP, Bath Ankylosing Spondylitis Functional Index (BASFI), C reactive protein (CRP), erythrocyte sedimentation rate (ESR), and review of their clinical profile.SpA patients had MBL levels ranging from 100 to 4100 ng/mL (median = 375 ng/mL); controls levels ranged from 100 to 4703 ng/mL (median = 1204 ng/mL; p0.0001). The prevalence of MBL deficiency was 27/89 (30.3%) in SpA patients and 12/89 (13.5%) in controls, with p = 0.01; OR = 2.5 (95% IC = 1.2-5.3). No association/correlation was found between MBL levels with BASDAI, BASFI, age at disease onset, ASDAS-CRP, ESR, CRP, presence of uveitis, HLAB27, peripheral arthritis, or SpA subtype (all p = NS).MBL levels may be linked with the occurrence of SpA but do not influence its phenotype.

Background Antinuclear antibodies (ANA) have been found in several types of cancer although the meaning of its presence is not completely known. Aim To study the prevalence of ANA in patients with cervical intraepithelial lesion and invasive cervical cancer. Methods A total of 205 women who underwent screening for cervical cancer or treatment at the Erasto Gaertner Cancer Hospital in Curitiba - Brazil, were enrolled in the study. Based on their latest cervical colposcopy-guided biopsy results, they were divided into four groups: CIN-I: 19.4%; CIN-II: 24.0%; CIN-III: 24.0%; and invasive cancer: 32.4%. As control were studied 68 healthy controls. ANA was searched by immunofluorescence in Hep-2 cells evaluating the pattern and titer. Results Controls had 4/68 (5.8%) of ANA positivity and patients with CIN and invasive cancer had 15.1% (p = 0.001). Patients with CIN-I and CIN-II had the same prevalence of ANA as controls (p = 1.0 and p = 0.11 respectively), but not those with CIN-III (p = 0.03) and invasive cancer (p = 0.05). The most common ANA immunofluorescence pattern was fine speckled pattern (38.7%) and fine dense speckled pattern (38.7%); the mean titer was 1:160. Conclusion ANA is more common in invasive cervical lesions than in controls or non invasive lesions. To understand the meaning of this finding more studies are needed.

Gut inflammation is closely related to spondyloarthritis (SpA) pathophysiology. Fecal calprotectin has been used to measure the degree of gut inflammation. The phenotype of SpA may change according to studied population.To study the fecal calprotectin levels in a sample of SpA in Brazilian patients and its relationship with epidemiological, clinical and treatment variables as well as with the macro and microscopic degree of gut inflammation.Eighty five SpA patients were studied for epidemiological and clinical features, functional and inflammatory indexes and fecal calprotectin levels measured using a ELISA kit. Colonoscopy with intestinal biopsies were performed in 39 of them. At time of colonoscopy a second calprotectin level was done after suspension of at least 3 weeks of used anti-inflammatory nonsteroidal drugs (NSAIDs).Fecal calprotectin levels were higher in Ankylosing Spondylitis (AS) patients (p 0.0001) and in those with axial involvement (p = 0.002). No relationship was found with SpA inflammatory and functional parameters (all p = ns). After suspension of NSAIDs, a drop in fecal calprotectin levels was observed (from median levels of 215.0-76.0 μg/g; p = 0.01). In the colonoscopy, 33.3% had macroscopic signs of inflammation and these patients had higher calprotectin (p = 0.009) than others. Microscopic examination showed that all patients had lymphoplasmacytic infiltrate and eosinophilic infiltrate; epithelial erosion was present in 27.2%.Patients with ankylosing spondylitis and axial forms of diseases have higher fecal calprotectin levels. Patients with all types of SpA have microscopic inflammatory changes in the gut.

Background: MBL-associated serine proteases (MASP-1, MASP-2, MASP-3, MAp-44, and MAp-19) are key factors in the activation of the lectin pathway of complement. Serum levels of these components have been associated with recurrence and poor survival of some types of cancer, such as colorectal and ovarian cancer. In this investigation, we determined the serum levels of MASP-1, MASP-2, MASP-3, MAp-44, and MAp-19 in patients with cervical cancer and cervical intraepithelial neoplasia (CIN). Methods:A total of 351 women who underwent screening for cervical cancer or treatment at the Erasto Gaertner Cancer Hospital in Curitiba-Brazil, were enrolled in the study. Based on their latest cervical colposcopy-guided biopsy results, they were divided into four groups: CIN-I: n = 52; CIN-II: n = 73; CIN-III: n = 141; and invasive cancer: n = 78. All the serum protein levels were determined by time-resolved immunofluorometric assay (TRIFMA). Results:Patients with invasive cancer presented significantly higher MASP-2, MASP-1, and MAp-19 serum levels than other groups (p < 0.0001; p = 0.012; p = 0.025 respectively). No statistically significant differences in MASP-3 and MAp-44 serum levels were found between the four studied groups. In addition, high MASP-2, MASP-1, and MAp-19 serum levels were significantly associated with poor survival in patients with invasive cancer and relapse (p = 0.002, p = 0.0035 and p = 0.025, respectively). Conclusion:High MASP-2, MASP-1, and MAp-19 serum levels were associated with cervical cancer progression and worse disease prognosis. These novel findings demonstrate the involvement of the serine proteases of the lectin pathway in the pathogenesis of cervical cancer and future investigations should clarify their role in the disease process.

The complement system is a key component of the innate immune system, participating in the surveillance against infectious agents. Once activated by one of the three different pathways, complement mediates cell lysis, opsonization, signalizes pathogens for phagocytosis and induces the adaptive immune response. The lectin pathway is constituted by several soluble and membrane bound proteins, called pattern recognition molecules (PRM), including mannose binding lectin (MBL), Ficolins-1, -2, and -3, and Collectin 11. These PRMs act on complement activation as recognition molecules of pathogen-associated molecular patterns (PAMPs) such as N-acetylated, found in glycoproteins of viral envelopes. In this study, Ficolin-1 and Ficolin-3 plasma levels were evaluated in 178 HIV patients (93 HIV; 85 HIV/HCV) and 85 controls from southern Brazil. Demographic and clinical-laboratory findings were obtained during medical interview and from medical records. All parameters were assessed by logistic regression, adjusted for age, ancestry, and sex. Significantly lower levels of Ficolin-1 were observed in HIV/HCV coinfected when compared to HIV patients (p = 0.005, median = 516 vs. 667 ng/ul, respectively) and to controls (p < 0.0001, 1186 ng/ul). Ficolin-1 levels were lower in males than in females among HIV patients (p = 0.03) and controls (p = 0.0003), but no association of Ficolin-1 levels with AIDS was observed. On the other hand, Ficolin-3 levels were significantly lower in controls when compared to HIV (p < 0.0001, medians 18,240 vs. 44,030 ng/ml, respectively) and HIV/HCV coinfected (p < 0.0001, 40,351 ng/ml) patients. There was no correlation between Ficolin-1 and Ficolin-3 levels and age, HIV viral load or opportunistic infections. However, Ficolin-3 showed a positive correlation with T CD4 cell counts in HIV monoinfected patients (p = 0.007). We provide here the first assessment of Ficolin-1 and-3 levels in HIV and HIV/HCV coinfected patients, which indicates a distinct role for these pattern recognition molecules in both viral infections.

Summary The aim of the study was to investigate the allotypic variability of complement factor B (BF) in patients and relatives with rheumatoid arthritis (RA) and its association with serological biomarkers and clinical features of the disease. BF allotypes were determined by high-voltage agarose gel electrophoresis in serum samples of 180 patients with RA, 198 relatives and 98 controls from Southern Brazil. Anticyclic citrullinated peptide (anti-CCP), antimutated citrullinated vimentin (anti-MCV) and IgA-rheumatoid factor (RF) were determined by ELISA and IgM-RF by latex agglutination in all samples. No significant differences were found in the allotypic variants of BF between patients with RA, relatives and controls, nor associations with gender and age of RA onset. BF*S07 allotype was significantly associated with extra-articular manifestations (EAMs; Secondary Sjogren Syndrome, pneumonitis, rheumatoid nodules) in patients with RA (P = 0.02; OR = 6.62). Patients with phenotype BF F had lower positivity for anti-MCV biomarker (P = 0.02; OR = 0.22) and those with allotype BF*S had higher prevalence of this autoantibody (P = 0.02; OR = 3.77). An increased frequency of RF-IgA was detected in relatives of patients with RA with BF FS07 phenotype (P = 0.02; OR = 7.78). Complement BF variability did not influence the development of RA in the studied patients, but BF variants may act as markers of disease prognosis, such as development of EAMs, corroborating with the role of the alternative pathway in the pathogenesis of RA.

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

We aimed to investigate the association between plasma levels of complement Factor H (FH) with cardiac involvement, inflammatory and cardiometabolic parameters in patients with chronic Chagas' disease (CD). FH plasmatic levels were determined in 80 chronic CD patients. Glycaemic index, lipidogram (high-density lipoprotein cholesterol HDL-C, low-density lipoprotein cholesterol LDL-C, triglycerides and total cholesterol) and Ultrasensitive C-Reactive Protein (uCRP) values were obtained from medical records. Height, weight, body mass index (BMI) blood pressure and left ventricular ejection fraction (LVEF) were obtained from echocardiography examinations. Comparisons between chronic CD clinical forms were performed using Mann-Whitney test and correlation Spearman's test. FH levels were correlated positively with triglycerides (P = .001, r = .39), LDL-C (P = .009, r = .3), cholesterol (P = .02, r = .28), uCRP (P = .029, r = .31) and BMI (P = .008, r = .34); and negatively with HDL-C (P = .03, r = -.25) levels. Dyslipidemic patients showed higher FH levels compared to normolipidemic, although no difference for FH levels was observed between chronic CD clinical forms. Alternative pathway of complement may be a link between immune response and metabolic disorders, with important immunoregulatory role in chronic CD.

Background/Aims: Arthropathy is the most common extraintestinal manifestation observed in patients with Crohn's disease (CD). The present study aimed to screen rheumatoid arthritis (RA) using anti-CCP antibodies and rheumatoid factor (RF) in CD patients from Southern Brazil. Additionally, the presence of arthralgia and spondyloarthritis (SpA) was evaluated. CD patients, previously diagnosed using clinical data, imaging tests, endoscopic and histological findings, were included consecutively. Methods: A total of 100 patients participated in the study, of which 60% were female, with a mean age of 41.9 ± 12.04 (16-83 years). As controls, sera from 100 healthy individuals from the same geographic area were analyzed. Results: Arthralgias were present in 55% of the patients, being more frequent in women (65.5%; 36/55), than in males (34.5%). No association was found between arthralgia and the treatment method used. Six patients (6/100) had SpA previously diagnosed. In the CD group, anti-CCP was positive only in one patient, while RF was positive in 7 patients (7%; 7/100). The anti-CCP positive patient (woman, 38 years old, RF positive), fulfilled the ACR criteria and was diagnosed as RA. In the control group, anti-CCP antibodies were detected in 1% (1/100) and RF was positive in 6 of the samples (6%). Conclusion: Our data showed low frequency of anti-CCP antibodies and RF in Brazilian patients with CD. Additionally, we found a high prevalence of arthralgia in these patients, with 6% of them diagnosed with SpA.

To investigate the association between mannose-binding lectin (MBL) serum level and MBL2 polymorphisms, and the frequency of spontaneous miscarriages in rheumatoid arthritis (RA) patients.One hundred seventy seven women (mean age 50 years) with RA from Southern Brazil were studied and 4.5% had a history of abortion (8/177). The MBL levels were determined by ELISA. MBL2 polymorphisms in the promoter (-550H/L, -221X/Y), 5' untranslated region (4 P/Q) and exon 1 (p.Gly54Asp: B allele, p.Arg52Cys: D allele and p.Gly57Glu: C allele; collectively labelled O) were genotyped by sequencing.Mannose-binding lectin levels of RA patients ranged from ≤100 ng/mL to 6640 ng/mL (median 541.5 ng/mL). There was a significant difference in MBL median levels (100 ng/mL vs. 625 ng/mL, respectively, p = .001) and frequency of MBL deficiency (75.0% vs. 24.1%, p = .007, OR = 10.3, 95%CI = 1.9-55.4), in patients with a history of miscarriage vs those without it. Patients with RA and miscarriage had more frequently haplotypes related with low MBL levels (p = .007, OR = 10.5, 95%CI = 1.3-84) than high producers. Moreover, LYPB haplotype and O allele were significantly associated with the occurrence of miscarriage (p = .001, OR = 9.7, 95%CI = 2.4-39.1 and p = .009, OR = 5.9, 95%CI = 1.4-23.4, respectively).The results suggest that MBL deficiency and the presence of MBL2 gene polymorphisms that lead to MBL deficiency are risk factors for the occurrence of miscarriage in patients with RA.

Mannan-binding lectin (MBL) and MBL-associated serine protease 2 (MASP-2) are components of the lectin pathway, which activate the complement system after binding to the HCV structural proteins E1 and E2. We haplotyped 11 MASP2 polymorphisms in 103 HCV patients and 205 controls and measured MASP-2 levels in 67 HCV patients and 77 controls to better understand the role of MASP-2 in hepatitis C susceptibility and disease severity according to viral genotype and fibrosis levels. The haplotype block MASP2*ARDP was associated with protection against HCV infection (OR = 0.49, p = .044) and lower MASP-2 levels in controls (p = .021), while haplotype block AGTDVRC was significantly increased in patients (OR = 7.58, p = .003). MASP-2 levels were lower in patients than in controls (p

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., Author summary Leprosy is considered a neglected disease and still a public health problem in many countries where it was not yet eliminated, leading to a high disability rate and social stigma. The molecular mechanisms of M. leprae infection and immune evasion are still poorly known, raising the need for studies that may contribute to a better understanding of leprosy etiology, as well as improvement in diagnosis and treatment. Ficolin-3 is a soluble molecule of the innate immune system that recognizes a wide range of pathogen-associated molecular patterns leading to complement activation and phagocytosis. We observed high concentration of ficolin-3 in leprosy patients, likely caused by polymorphisms present in intronic regions of FCN3 gene, which may contribute to leprosy susceptibility by favoring M. leprae infection. This is the first study addressing FCN3 polymorphisms and ficolin-3 levels in leprosy, indicating it as a good candidate biomarker associated with the host response against M. leprae.

Introduction Mannose binding lectin (MBL) has been linked to predisposition to systemic lupus erythematosus (SLE) and to disease activity. Some studies found deposits of MBL in glomerular tissue of patients with lupus nephritis. There is no research about the deposition of MBL in skin. Materials and methods Skin biopsies from lesional and non lesional skin of 4 discoid lupus erythematosus (DLE) and 10 SLE patients were submitted to immunofluorescence staining for IgG, IgA, IgM, C3, C4, C1q, C5b-9 and MBL. Charts were reviewed for demographic, clinical and serological data. Patients with SLE had disease activity measured by SLEDAI. Results MBL was found only in SLE lesional skin and its presence showed an association trend towards higher disease activity. Deposition of C5b-9 occurred in vessels only in patients with SLE (70%) and in the two patients with kidney involvement. Conclusions MBL deposition was found in the lesional skin of SLE patients but not in SLE non lesional skin nor in DLE patients, and it seems to be less frequent and less strong than observed in the kidneys biopsies, suggesting that the complement participation in the pathophysiology of SLE process may not be the same in these two clinical manifestations.

Mannan-binding lectin (MBL) - associated serine protease 2 (MASP-2) co-activates the lectin pathway of complement in response to several viral infections. The quality of this response partly depends on MASP2 gene polymorphisms, which modulate MASP-2 function and serum levels. In this study we investigated a possible role of MASP2 polymorphisms, MASP-2 serum levels and MBL-mediated complement activation in the susceptibility to HIV/AIDS and HBV/HCV coinfection.A total of 178 HIV patients, 89 (50%) coinfected with HBV/HCV, 51.7% female, average age 40 (12-73) years, and 385 controls were evaluated. MASP-2 levels and MBL-driven complement activation were evaluated by enzyme-linked immunosorbent assay and 11 MASP2 polymorphisms from the promoter to the last exon were haplotyped using multiplex sequence-specific PCR.Genotype distribution was in Hardy-Weinberg equilibrium and differed between HIV+ patients and controls (P=0.030), irrespective of HBV or HCV coinfection. The p.126L variant, which was associated with MASP-2 levels 200ng/mL (OR=5.0 [95%CI=1.3-19.2] P=0.019), increased the susceptibility to HIV infection (OR=5.67 [95%CI=1.75-18.33], P=0.004) and to HIV+HBV+ status (OR=6.44 [95%CI=1.69-24.53, P=0.006). A similar association occurred with the ancient haplotype harboring this variant, AGCDV (OR=2.35 [95%CI=1.31-4.23], P=0.004). On the other hand, p.126L in addition to other variants associated with low MASP-2 levels-p.120G, p.377A and p.439H, presented a protective effect against AIDS (OR=0.25 [95%CI=0.08-0.80], P=0.020), independently of age, sex, hepatic function and viral load. MASP-2 serum levels were lower in HIV+ and HIV+HBV+ patients than in controls (P=0.0004). Among patients, MASP-2 levels were higher in patients with opportunistic diseases (P=0.001) and AIDS (P=0.004). MASP-2 levels correlated positively with MBL/MASP2-mediated C4 deposition (r=0.29, P=0.0002) and negatively with CD4+ cell counts (r=-0.21, P=0.018), being related to decreased CD4+ cell counts (OR=5.8 [95%CI=1.23-27.5, P=0.026).Genetically determined MASP-2 levels seem to have a two-edge effect in HIV and probably HCV/HBV coinfection, whereas low levels increase the susceptibility to infection, but on the other side protects against AIDS.

Hepatitis C virus (HCV) has become a major public health issue and is prevalent in most countries. We examined several MASP2 functional polymorphisms in 104 Brazilian patients with moderate and severe chronic hepatitis C using the primers set to amplify the region encoding the first domain (CUB1), a critical region for the formation of functional mannan-binding lectin (MBL)/MBL-associated serine proteases (MASP)–2 complexes, and the fifth domain (CCP2), which is essential for C4 cleavage of the MASP2 gene. We identified five single nucleotide polymorphisms in patients and controls: p. R99Q, p. D120G, p.P126L, p.D371Y, and p.V377A. Our results show that the p.D371Y variant (c.1111 G > T) is associated with susceptibility to HCV infection (p = 0.003, odds ratio = 6.33, 95% confidence interval = 1.85–21.70). Considered as a dominant function for the T allele, this variant is associated with high plasma levels of the MASP-2 in hepatitis C patients (p < 0.001). However, further functional investigations are necessary to understand the degree of involvement between MASP2 and the HCV susceptibility.

Scarce data are available about the antimicrobial resistance of Group A Streptococcus in South America.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.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).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.

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.

Background Pathophysiological mechanisms are still incompletely understood for leprosy, an urgent public health issue in Brazil. Complement receptor 1 (CR1) binds complement fragments C3b/C4b deposited on mycobacteria, mediating its entrance in macrophages. We investigated CR1 polymorphisms, gene expression and soluble CR1 levels in a case-control study with Brazilian leprosy patients, aiming to understand the role of this receptor in differential susceptibility to the disease. Methodology Nine polymorphisms were haplotyped by multiplex PCR-SSP in 213 leprosy patients (47% multibacillary) and 297 controls. mRNA levels were measured by qPCR and sCR1 by ELISA, in up to 80 samples. Principal findings Individuals with the most common recombinant haplotype harboring rs3849266*T in intron 21 and rs3737002*T in exon 26 (encoding p.1408Met of the York Yka+ antigen), presented twice higher susceptibility to leprosy (OR = 2.43, p = 0.017). Paucibacillary patients with these variants presented lower sCR1 levels, thus reducing the anti-inflammatory response (p = 0.040 and p = 0.046, respectively). Furthermore, the most ancient haplotype increased susceptibility to the multibacillary clinical form (OR = 3.04, p = 0.01) and presented the intronic rs12034383*G allele, which was associated with higher gene expression (p = 0.043), probably increasing internalization of the parasite. Furthermore, there was an inverse correlation between the levels of sCR1 and mannose-binding lectin (initiator molecule of the lectin pathway of complement, recognized by CR1) (R = -0.52, p = 0.007). Conclusions The results lead us to suggest a regulatory role for CR1 polymorphisms on mRNA and sCR1 levels, with haplotype-specific effects increasing susceptibility to leprosy, probably by enhancing parasite phagocytosis and inflammation., Author summary The reasons for which some individuals resist Mycobacteria leprae infection, whereas others contract leprosy and only a subgroup of them become severely affected, are still poorly understood. The complement receptor 1 (CR1) serves as a gate for bacterial entry in macrophages, but its importance in the spread of infection and emergence of symptoms is unknown. Despite having many common structural and regulatory variants, the CR1 gene was investigated only once in a leprosy association study in Malawi. In order to fill in this gap, we investigated if CR1 polymorphisms are co-responsible for differential disease susceptibility in 213 leprosy patients and 297 controls, also measuring mRNA and soluble CR1 levels. Associations were dependent on specific combinations of variants in regulatory and coding regions, which were also associated with gene and protein expression. Thus, this study corroborates the importance of the CR1 receptor in the susceptibility to leprosy and is the first to bring information about CR1 polymorphisms in the Brazilian population, as well as to show the relationship between genotypes and mRNA and sCR1 levels.

Low concentration of mannan-binding lectin (MBL) has been related to unexplained spontaneous abortion (SA), which has also been observed in an increased frequency in patients with celiac disease (CD). In this study, plasma levels of MBL were determined in patients with CD and irritable bowel syndrome (IBS) in order to investigate whether there is an association of MBL levels and the occurrence of SA in these patients. MBL concentration was determined in 46 patients with CD (28 without and 18 with report of SA) and 38 patients with IBS (25 without and 13 with report of SA). A higher frequency of SA was observed in women with CD when compared to IBS patients (23.2 vs. 13.9%; P = 0.046). No significant difference was observed in MBL concentrations between patients with CD, IBS, and healthy controls, nor between patients with or without occurrence of SA. These results suggest that the serum levels of MBL and the occurrence of SA in women with CD and IBS are not causally related.

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 (p0.6). 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.

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

Although most with Chagas Disease (CD) stay asymptomatic indefinitely, about one third of them progress to chronic cardiomyopathy. Since mannose-binding lectin (MBL) seems to have a relevant role in tissue injury present in inflammatory cardiac disorders we aimed to investigate a possible association of MBL levels with the susceptibility and clinical progression of CD. A total of 150 CD patients presenting indeterminate, cardiac, digestive and associated forms and 139 controls were studied. MBL levels were determined by ELISA and C-reactive protein (hs-CRP) by nephelometry. High MBL values (>1000ng/ml) were associated with the severity of CD cardiomyopathy in both patients with echocardiographic alterations [O.R=25.88; I.C. 95%: 3.07–217.9; p =0.00013] and cardiac insufficiency [O.R=2.91; I.C. 95%: 1.08–7.80; p =0.02] when compared to patients without those conditions. Increased MBL levels may contribute to the inflammatory process and myocardial injury in chronic CD.

BackgroundThe 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.MethodsWe 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.ResultsTwo 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).ConclusionsIn 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.

This report describes a cross-sectional survey on the prevalence of hepatitis C antibodies (anti-HCV) in Tamboara, a small community in the northwest area from Paraná State, south of Brazil with a high rate of accumulated detection for HCV. Eight hundred and sixteen residents (17.87% from all the population), independently of the age and time living in Tamboara were included in this study by an epidemiologic questionnaire and by testing for anti-HCV. The rapid immuno-chromatographic test was applied for detection of HCV antibodies. The anti-HCV prevalence by rapid test was 4.28%. The median age for positive and negative test was 60.49 ± 14.14 and 41.67 ± 20.25, respectively (p < 0.001). By multivariate analysis, only familial history of hepatitis (p = 0.001; OR = 6.41; CI 95% = 2.08-19.78) and age (p = 0.007; OR 1.06;95% CI = 1.02-1.10) showed statistical significance for positive anti-HCV. The rapid test sensitivity and specificity were 100% and 92.7% respectively, with an accuracy of 95.8% (95% CI = 91-100). These findings demonstrated a high prevalence of anti-HCV in Tamboara. The familial history of hepatitis was a significant risk factor to the infection and HCV rapid test showed to be accurate and feasible for epidemiological survey. Keywords: hepatitis C, epidemiology, Brazil

BackgroundMannose binding lectin (MBL) has an important role in the activation of the complement system and opsonization of pathogenic microorganisms. Frequent polymorphisms found in theMBL2gene affect the concentration and functionality of the protein and are associated with enhanced susceptibility to severe malaria in African children. MostMBL2typing strategies were designed to the analysis of selected variants, the significance of whole haplotypes is poorly known. In this work, a new typing strategy was developed and validated in an association analysis ofMBL2with adult asymptomatic infection.MethodsMBL2allele-specific fragments of 144 healthy Gabonese adults were amplified by using haplotype-specific sequencing (HSS), a new strategy that combines sequence-specific PCR and sequence-based typing. The Gabonese were investigated for the presence ofPlasmodium falciparumparasitaemia by the amplification of parasite genes, immunochromatographic antigen detection and microscopic analysis. HSS results were also compared with a previously used real-time PCR (RT-PCR) method in 72 Euro-Brazilians.ResultsFourteen polymorphisms were identified beside the commonly investigated promoter (H, L;X, Y;P, Q) and exon 1 (A, O;O=B,CorD) variants. TheMBL2*LYPA/LYPAgenotype was associated with the absence of asymptomatic infection (P = 0.017), whereas theMBL2*LYQChaplotype andYA/YO+YO/YOgenotypes were associated with positive parasite counts in asymptomatic adults (P = 0.033 and 0.018, respectively). The associations were specific toLYPA(identical to the reference sequence Y16577) andLYQC(Y16578) and would not have been revealed by standard genotyping, as there was no association withLYPAandLYQChaplotypes carrying new polymorphisms defined by sequence-based typing. In contrast, HSS and RT-PCR produced very similar results in the less diverse European-derived population.ConclusionIn this work, a new typing strategy for a highly polymorphic gene was developed and validated focusing on the asymptomatic status ofP. falciparum-infected adults. In populations with high nucleotide diversity, it allowed for the identification of associations with fine-scaled haplotypes that would not have been found using common typing techniques. In this preliminary study,MBL2haplotypes or SNPs linked to them were found associated with susceptibility to infection and parasitaemia control of asymptomatic adults.

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 >2800ng/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.

Chagas disease (CD) is caused by Trypanosoma cruzi, whose sugar moieties are recognized by mannan binding lectin (MBL), a soluble pattern-recognition molecule that activates the lectin pathway of complement. MBL levels and protein activity are affected by polymorphisms in the MBL2 gene. We sequenced the MBL2 promoter and exon 1 in 196 chronic CD patients and 202 controls. The MBL2*C allele, which causes MBL deficiency, was associated with protection against CD (P = 0.007, OR = 0.32). Compared with controls, genotypes with this allele were completely absent in patients with the cardiac form of the disease (P = 0.003). Furthermore, cardiac patients with genotypes causing MBL deficiency presented less heart damage (P = 0.003, OR = 0.23), compared with cardiac patients having the XA haplotype causing low MBL levels, but fully capable of activating complement (P = 0.005, OR = 7.07). Among the patients, those with alleles causing MBL deficiency presented lower levels of cytokines and chemokines possibly implicated in symptom development (IL9, p = 0.013; PDGFB, p = 0.036 and RANTES, p = 0.031). These findings suggest a protective effect of genetically determined MBL deficiency against the development and progression of chronic CD cardiomyopathy., Author Summary Chagas disease is considered an important neglected tropical disease, affecting approximately ten million people in Latin America. Although most infected individuals remain asymptomatic, one third of patients develop a chronic heart disease, with progressive inflammation, increase of myocardium, arrhythmia, cardiac insufficiency and heart failure. To date, there is no available marker to indicate the progression neither to determinate the severity of heart damage. Mannan binding lectin (MBL) is an important protein of the immune system able to recognize specific regions on the microorganism surfaces (including Trypanosoma cruzi, the causal agent of Chagas disease) which activate the complement system, a crucial mechanism of the effector immunity. MBL levels and protein activity are affected by genetic differences, named polymorphisms, in the MBL2 gene. This is the first Brazilian study with MBL2 polymorphisms in chronic Chagas disease. We sequenced two regions of MBL2 gene in 196 patients and 202 controls. We found that a polymorphism associated with deficient complement activation protects against Chagas disease and patients with deficiency-associated genotypes presented less echocardiographic alterations. Among the patients, those with alleles causing MBL deficiency presented lower levels of cytokines and chemokines possibly implicated in symptom development (IL9, p = 0.013; PDGFB, p = 0.036 and RANTES, p = 0.031). These findings lead us to suggest that genetically determined MBL deficiency plays a protective role against the development and progression of chronic Chagas disease.

The aim of the present study was to investigate a broad spectrum of autoantibodies in patients with endemic pemphigus foliaceus (EPF)—fogo selvagem—and to determine the possible association between EPF and other autoimmune diseases. Indirect immunofluorescence was used to test 120 patients with EPF and 200 healthy controls for the presence of the following autoantibodies: anti-desmoglein-1 (APF), anti-neutrophil cytoplasmic (ANCA), anti-smooth muscle (SMA), anti-mitochondrial (AMA), anti-nuclear (ANA), anti-liver kidney microsomal (LKM), anti-gastric parietal cells (GPCA) and anti-thyroid microsome (TMA). APF antibodies were detected in 62.5% of the patients (75/120), ANA and SMA in 0.8% (1/120), and TMA in 1.6% (2/120). None of the patients was positive for ANCA, AMA, LKM or GPCA. In the control group, a positivity of 2% was observed for SMA (4/200), 1.5% for TMA (3/200), and 0.5% (1/200) for ANA and GPCA. None of the controls was positive for APF, LKM, AMA or ANCA. The prevalence of the autoantibodies ANA, SMA, AMA, GPCA, LKM and ANCA in patients with EPF was similar to that observed in the control group. No association with clinical or laboratory manifestations of other concomitant autoimmune diseases was observed in EPF patients. These results confirm the concept that EPF is an organ-specific autoimmune disease.

SummaryIn an infectious process complement activation is necessary for a proper immune and inflammatory response, but when exacerbated may cause tissue injuries. In infective endocarditis (IE) patients tend to develop high titres of circulating immune complexes (CIC) that activate complement. The aim of this study was to evaluate for the first time complement activation in IE for possible correlation with extracardiac manifestations and clinical prognosis. Twenty patients with IE, 14 healthy controls and 15 patients presenting mitral and aortic valve lesions (with no signs of either infection or other associated diseases), were studied. Plasma levels of C3adesArg, SC5b-9, C1rs-C1Inh and C3b(Bb)P were determined by ELISA and C3d by double decker immunoelectrophoresis. C3 and C4 levels were assayed by turbidimetry and CIC by ELISA. Elevation of plasma levels of all complement activation products, with the exception of C3b(Bb)P, indicated a significant classical pathway activation in IE patients when compared to controls (C3d: P < 0·00004; C3adesArg: P < 0·03, SC5b-9: P < 0·01, C1rs-C1Inh: P < 0·00007). CIC levels were significantly increased (P < 0·005) and C3 reduced in IE patients (P < 0·05). Elevated C3d (P < 0·02) and C3adesArg (P < 0·03) levels were associated with pulmonary manifestations. In addition, C3d was significantly elevated in the patients who died when compared to those who had a good recovery (P < 0·02). Our data demonstrate the activation of the complement classical pathway, most probably mediated by CIC, in IE and suggests C3d and C3adesArg as possible markers for extracardiac lesion and severity of the disease.

BackgroundMannan-binding lectin-associated serine protease 2 (MASP-2) is a key protein of the lectin pathway of complement. MASP-2 levels have been associated with different polymorphisms within MASP2 gene as well as with the risk for inflammatory disorders and infections. Despite its clinical importance, MASP-2 remains poorly investigated in rheumatoid arthritis (RA).MethodsIn this case-control study, we measured MASP-2 serum levels in 156 RA patients, 44 patient relatives, and 100 controls from Southern Brazil, associating the results with nine MASP2 polymorphisms in all patients, 111 relatives, and 230 controls genotyped with multiplex SSP-PCR.ResultsMASP-2 levels were lower in patients than in controls and relatives (medians 181 vs. 340 or 285 ng/ml, respectively, PConclusionsIn this study, we found the first evidence that MASP-2 deficiency might play an important role in the development of RA and articular symptoms among relatives of RA patients.

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.