Can anti-PGL-I antibody isotypes differentiate leprosy contacts and leprosy patients?

BACKGROUND

Serological tests for antibody measurement in leprosy have a series of limitations in discriminating contacts and patients. The present paper intends to evaluate if association of more than one antibody isotype in serum samples may be a useful tool in leprosy diagnosis.

METHODS

This study evaluated 395 leprosy contacts and 71 leprosy index cases living in endemic municipalities in Northeastern Brazil. The participants were evaluated according to their anti-phenolic glycolipid antigen-I isotype (PGL-I) profile. Serum anti-PGL-I IgM, IgG, and IgA were measured by indirect ELISA.

RESULTS

A strong association was found for antibody positivity in MB leprosy index cases. The odds ratios were 6.11 (95% CI 3.08 - 12.16) for IgM, 3.31 (1.66 - 6.61) for IgG, and 16.97 (8.39 - 34.2) for IgA. For IgM associated with one or more isotypes, the OR was 21.0 (95% CI 10.11 - 43.64), and for IgG + IgA, the OR was 17.58 (6.23 - 49.54). The highest diagnostic sensitivity of 76.0% (95% CI 61.8 - 86.9) was observed for IgM, and the lowest value was 24.1% (13.0 - 38.2), which was observed for IgG + IgA isotypes. Regarding presumptive positive predictive values, the lowest value was obtained for IgM at 24.7% (95% CI 18.1 - 32.3), and the highest values were observed for IgM+ one or more isotypes and for IgG + IgA isotype at 60.0% (44.3 - 74.3) and 66.7% (41.0 - 86.7), respectively.

CONCLUSIONS

The present work demonstrated that by associating two or more positive antibody isotypes, the risk of facing a real case of leprosy may increase.

Antioxidant, anti-inflammatory and healing potential of ethyl acetate fraction of Bauhinia ungulata L. (Fabaceae) on in vitro and in vivo wound model

The present work aimed to investigate the antioxidant, anti-inflammatory and wound healing potential of ethyl acetate fraction from Bauhinia ungulata L. (FABU) on in vitro and in vivo models. Wound healing assay using human lung adenocarcinoma A549 cell line was employed to evaluate the ability of FABU in modulating cell migration. In addition, a surgical wound model in C57BL/6 mice was used to study the healing potential of FABU incorporated into gel carbomer 940 (Carbopol®). Evaluation of lipid peroxidation, inflammatory and anti-inflammatory mediator gene expression, rate of wound closure, and histological analysis were done. FABU significantly reduced the gap area in in vitro wound healing assay, 24 h after treatment. In the animal model, FABU at 0.5% topically applied once-daily for 5 days to the surgical wounds significantly reduced the lesion area. Moreover, it significantly decreased the levels of lipid peroxidation in the lesions and decreased the relative gene expression levels of IL-1β and TNF-α in the injured region. In conclusion, our study suggests that Bauhinia ungulata can effectively promote the wound healing, probably by regulating the inflammatory environment during the early stages of the process.

Nitro-imidazole-based ruthenium complexes with antioxidant and anti-inflammatory activities

Inflammation is a physiological process triggered in response to tissue damage, and involves events related to cell recruitment, cytokines release and reactive oxygen species (ROS) production. Failing to control the process duration lead to chronification and may be associated with the development of various pathologies, including autoimmune diseases and cancer. Considering the pharmacological potential of metal-based compounds, two new ruthenium complexes were synthesized: cis-[Ru(NO₂)(bpy)₂(5NIM)]PF₆ (1) and cis-[RuCl(bpy)₂(MTZ)]PF₆ (2), where bpy = 2,2'-bipyridine, 5NIM = 5-nitroimidazole and MTZ = metronidazole. Both products were characterized by spectroscopic techniques, followed by Density Functional Theory (DFT) calculations in order to support experimental findings. Afterwards, their in vitro cytotoxic, antioxidant and anti-inflammatory activities were investigated. Compounds 1 and 2 presented expressive in vitro antioxidant activity, reducing lipid peroxidation and decreasing intracellular ROS levels with comparable effectiveness to the standard steroidal drug dexamethasone or α-tocopherol. These complexes showed no noticeable cytotoxicity on the tested cancer cell lines. Bactericidal assay against metronidazole-resistant Helicobacter pylori, a microorganism able to disrupt oxidative balance, unraveled compound 1 moderate activity over that strain. Besides this, it was able to inhibit interleukin-6 (IL-6) and tumor necrosis factor-α (TNF- α) production as well as interleukin-1β (IL-1β) and cyclooxygenase-2 (COX-2) expression in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. This latter activity is remarkable, which has not been reported for other ruthenium-based complexes. Altogether, these results suggest cis-[Ru(NO₂)(bpy)₂(5NIM)]PF₆ complex has potential pharmacological application as an anti-inflammatory agent that deserve further biological investigation.

Polymorphism of IL10, IL4, CTLA4, and DAO Genes in Cross-Reactive Nonsteroidal Anti-inflammatory Drug Hypersensitivity

Our aim was to evaluate genetic polymorphism of molecules involved in immunoregulatory/allergic processes in patients who presented with cutaneous hypersensitivity caused by chemically unrelated nonsteroidal anti-inflammatory drugs. Polymorphisms at IL10 (-1082 G>A), IL4 (-589 C>T), CTLA4 (+49A>G), and DAO (+8956 C>G) genes were studied in 55 cases and 97 controls by the polymerase chain reaction-restriction fragment length polymorphism technique. With regard to the polymorphism at IL10 -1082, higher frequencies of the AG genotype (57% vs 39%) and G allele carriers (70% vs 48%) were found among the patients, indicating a risk effect (odds ratio [OR] = 2.56 and P = .01 for AG genotype and OR = 2.52; P = .01 for AG/GG). For the CTLA4 +49 A/G single-nucleotide polymorphism (SNP), AG genotype (31.0%) (P = .02) and G carrier (54.0%) (P = .05) frequencies were found to be significantly lower in the patient group compared with the control group (51.0% and 69.0%, respectively). The SNP DAO +8956 C>G was associated with a strong protective effect, with OR values of 0.83 for CG and 0.11 for GG genotype (P = .04 for the codominant model), suggesting an allele dose effect. The combination of IL10 and DAO SNPs in a multivariate model did not alter the OR values, suggesting independent effects for both SNPs. The results are striking. In conclusion, these results suggest that polymorphisms in regulatory targets of the immune response and in DAO gene could modulate an individual's susceptibility to nonsteroidal anti-inflammatory drug hypersensitivity reactions. Further studies will be necessary to complement our results.

Salivary anti-PGL-1 IgM may indicate active transmission of Mycobacterium leprae among young people under 16 years of age

Considering that the main route of Mycobacterium leprae transmission is the upper respiratory tract, detection of salivary antibodies can be a useful tool for diagnosing early infection. The study aimed to analyze salivary anti-PGL-1 IgA and IgM antibodies in 169 children aged 4–16 years old, who lived nearby or inside the house of multibacillary or paucibacillary leprosy patients in two endemic cities in Alagoas State – Brazil. Salivary anti-PGL-1 antibodies were quantified by modified ELISA method. The frequency of contact and clinical form of the index case were significantly associated with salivary antibody levels. High frequency of IgM positivity strongly suggests active transmission of M. leprae in these communities. We suggest in the present work that salivary anti-PGL IgA and IgM are important biomarkers to be used for identifying communities with probable active transmission of M. leprae.

Association of IL10, IL4, IFNG, and CTLA4 Gene Polymorphisms with Efavirenz Hypersensitivity Reaction in Patients Infected with Human Immunodeficiency Virus

We evaluated interleukin-10 (IL10) －592 C/A, IL4－589 C/T, interferon gamma (IFNG)＋874 A/T, cytotoxic T-lymphocyte-associated antigen 4 (CTLA4)＋49 A/G gene polymorphisms associated with efavirenz hypersensitivity reaction. A total of 63 human immunodeficiency virus-positive patients under treatment at a public hospital were included in the study, of whom 21 presented with efavirenz hypersensitivity. Patients who presented with efavirenz hypersensitivity reaction showed a higher frequency of the IL10 －592A allele than the controls (p＝0.028). The allele A was associated with increased risk of efavirenz hypersensitivity (odds ratio＝2.40). In case of IL4, a significant difference in the frequency of the IL4 －589 (C/T) polymorphism was not observed between patients and controls. A significant inverse correlation was observed when comparing the CTLA4＋49A/G and IL4 －589 C/T polymorphisms (r＝－0.650, p＝0.001); that is, the CTLA4 +49GG genotype, involved with the lowest capacity of inhibition, was inversely correlated IL4－589TT genotype, which induces high production of IL-4. With respect to the CTLA4＋49A/G and IFNG＋874T/A gene polymorphisms, significant differences in allele and genotype frequencies were not observed between the groups. Therefore, our data suggest that polymorphisms in regulatory regions of cytokine genes could modulate an individual's susceptibility to efavirenz hypersensitivity reaction.

CD38+CD8+ and CD38+CD4+ T Cells and IFN Gamma (+874) Polymorphism Are Associated with a Poor Virological Outcome

The main objective of the work was to evaluate the use of CD38 on T lymphocytes, IFNγ (+874 A/T), and IL-10 (-1082 A/G) polymorphisms in HIV-infected patients under antiretroviral (ARV) therapy. Sixty-one patients were selected at the outpatient clinic for HIV infection at the Hospital São José de Doenças Infecciosas, Fortaleza, Ceará, Brazil. The patients were classified into two groups, according to viral load after one year of ARV therapy. In the aviremic group (group I), a reduction of 35.5% of CD38+CD4+ T cells was observed (p = 0.02) and 49.3% of CD38+CD8+ T cells (p = 0.001). In the viremic group (group II), a reduction of 37.2% of CD38+CD4+ T cells (p = 0.067), and 21.4% of CD38+CD8+ T cells (p = 0.60) occurred. No association was found between IL-10 (-1082) polymorphism and the type of response to ARV therapy. Regarding the gene polymorphism on IFNγ (+874 T/A), 73.34% of group I and 33.3% of group II presented the AA genotype. The relative risk of the individuals carrying AA genotype or the A allele and not being able to suppress the viral load level after one year of ARV therapy was 3.44 (1.25-9.45; p = 0.014) or 2.35 (1.05-5.26; p = 0.027), respectively. Our data suggested that an augmented frequency of activated CD38+CD8+ T cells as well as the presence of the A allele of IFNγ polymorphism could contribute to a reduced virological suppression in patients under antiretroviral therapy.

Interleukin-10 gene polymorphism (−1082G/A) and allergy to efavirenz in patients infected with human immunodeficiency virus

The aim of the present study was to investigate the association between polymorphism in the interleukin-10 gene promoter at position −1082 in human immunodeficiency virus-infected patients who had presented allergic reaction due to efavirenz. The study included 63 patients treated at the Hospital São José de Doenças Infecciosas, Fortaleza, Ceará, Brazil. Twenty-one patients who had presented allergic reaction to efavirenz were compared to 42 patients with no allergic reaction following exposure to this drug. Blood samples were collected for DNA extraction and submitted to the restriction fragment length polymorphism – polymerase chain reaction technique. The −1082AA genotype was significantly more frequent in allergic patients as compared to non-allergic patients (p = 0.019; χ² = 5.534; OR = 3.625; 95% CI = 1.210–10.860). Likewise the allele IL-10 −1082A was identified significantly more often among efavirenz allergic patients than in the non-allergic group (p = 0.009; χ² = 6.787; OR = 3.029; 95% CI = 1.290–7.111). These findings suggest that the polymorphism in the interleukin-10 gene promoter −1082G/A can be related to the development of allergic reactions to efavirenz.

Clinical and serological evolution in chronic Chagas disease patients in a 4-year pharmacotherapy follow-up: a preliminary study

INTRODUCTION

The role of trypanocidal therapy in the chronic phase of Chagas disease remains controversial.

METHODS

A total of 13 patients with chronic Chagas disease were treated with benznidazole (5mg/kg/day/60 days) and surveyed via antibody measurement and conventional electrocardiogram over the course of 4 years.

RESULTS

The antibody titers were significantly reduced after 4 years (p<0.05). Most of the patients showed maintenance of the initial clinical picture (electrocardiographic), with the exception of 4 cases.

CONCLUSIONS

Although trypanocidal therapy in the chronic phase of Chagas disease was of limited effectiveness, we believe that it is beneficial in treating these patients.

Anti-PGL1 salivary IgA/IgM, serum IgG/IgM, and nasal Mycobacterium leprae DNA in individuals with household contact with leprosy

OBJECTIVES

Leprosy household contacts represent a group at high risk of developing the disease. The aim of this study was to detect Mycobacterium leprae subclinical infection in this group through serological and molecular parameters.

METHODS

Serum anti-PGL1 IgG/IgM and salivary anti-PGL1 IgA/IgM was investigated using an ELISA, and nasal carriage of M. leprae DNA was detected by PCR, in leprosy household contacts of paucibacillary (PB) and multibacillary (MB) household leprosy patients (n=135), their index cases (n=30), and in persons living in a low endemic city (n=17).

RESULTS

Salivary anti-PGL1 IgA and IgM and serum anti-PGL1 IgG showed good correlation comparing contacts and index cases (p<0.01, p<0.005, and p<0.0001, respectively). This was not observed for serum anti-PGL1 IgM (p>0.05). A high frequency of anti-PGL1 IgM positivity was found in IgG-negative samples (p<0.0001). For IgG-positive samples, IgM antibodies were also positive in most of the samples. None of the 17 volunteers living in a low endemic city presented seropositivity for IgG; however, two of them showed positivity for anti-PGL1 IgM. M. leprae DNA was found in the nasal swabs of nine out of the 85 MB household leprosy contacts (10.6%) and in three out of the 50 PB household leprosy contacts (6.0%).

CONCLUSION

We strongly suggest that serum IgG/IgM and salivary anti-PGL1 IgA/IgM measurements are used to follow leprosy household contacts.

Burkholderia pseudomallei antibodies in individuals living in endemic regions in Northeastern Brazil

A seroepidemiological investigation was conducted among the population of two municipalities in Northeastern Brazil. Immunoglobulin M (IgM) and IgG antibodies to Burkholderia pseudomallei were positive in 51.27% (161 in 317 samples) and 58.49% (186), respectively. IgM titers were higher in children than in adults. On the contrary, IgG increased progressively with age. We observed a significant association between agricultural occupation and raised IgM titers (P < 0.005) and IgG titers (P < 0.001), and between construction workers and raised IgG titers (P = 0.005). Antibody IgG avidities did not correlate with age. The highest titers of antibodies (1/800) showed the highest antibody avidity indexes (P < 0.01). Most of the serum samples recognized 45-kDa and 200-kDa bands by IgG1 and IgG2 subclasses. Our study showed a high seropositivity among individuals living in endemic regions of the state of Ceará, and highlights the need for further surveillance close to water courses such as dams and rivers in Northeastern Brazil.

Implementation of a penicillin allergy skin test

The penicillin allergy skin testing is the only accurate and reliable test for penicillin hypersensitivity mediated by IgE. It is useful for identifying patients with doubtful history of allergy. Positive test for major and minor determinants presents a positive predictive value of 50% and negative predictive value of 99%. In Brazil, the Ministry of Health suggests a protocol for in house made reagents, since they are not commercially available. As the referred protocol does not mention some important details about the test procedures, we propose in the present work to implement them, critically evaluating each step in order to allow the protocol establishment at any health service, with quality and safety.