Downmodulation of Regulatory T Cells Producing TGF-β Participates in Pathogenesis of Leprosy Reactions.

Leprosy reactions are an acute and systemic manifestation, which occurs suddenly, can be severe and lead leprosy patients to disability. Reactional episodes are observed among half of the multibacillary patients, mainly in borderline lepromatous and lepromatous forms. They may begin at any time during multidrug therapy, and even before the treatment.

Presence of Senescent and Memory CD8+ Leukocytes as Immunocenescence Markers in Skin Lesions of Elderly Leprosy Patients.

Leprosy is an infectious disease that remains endemic in approximately 100 developing countries, where about 200,000 new cases are diagnosed each year. Moreover, multibacillary leprosy, the most contagious form of the disease, has been detected at continuously higher rates among Brazilian elderly people. Due to the so-called immunosenescence, characterized by several alterations in the quality of the immune response during aging, this group is more susceptible to infectious diseases.

Increased oxidative stress in elderly leprosy patients is related to age but not to bacillary load.

Background: Leprosy continues to be a public health problem in Brazil. Furthermore, detection rates in elderly people have increased, particularly those of multibacillary (L-Lep) patients, who are responsible for transmitting M. leprae.

Involvement of TNF-Producing CD8 Effector Memory T Cells with Immunopathogenesis of Erythema Nodosum Leprosum in Leprosy Patients.

Type 2 reaction (T2R) or (ENL), a sudden episode of acute inflammation predominantly affecting lepromatous leprosy patients (LL), characterized by a reduced cellular immune response. This possibly indicates a close relationship between the onset of T2R and the altered frequency, and functional activity of T lymphocytes, particularly of memory subsets. This study performed ex vivo and in vitro characterizations of T cell blood subpopulations from LL patients with or without T2R.

Blood coagulation abnormalities in multibacillary leprosy patients.

Background: Leprosy is a chronic dermato-neurological disease caused by Mycobacterium leprae infection. In 2016, more than 200,000 new cases of leprosy were detected around the world, representing the most frequent cause of infectious irreversible deformities and disabilities.

Principal Findings: In the present work, we demonstrate a consistent procoagulant profile on 40 reactional and non-reactional multibacillary leprosy patients.

Role of TEFFECTOR/MEMORY Cells, TBX21 Gene Expression and T-Cell Homing Receptor on Type 1 Reaction in Borderline Lepromatous Leprosy Patients.

In spite of hyporesponsivity to Mycobacterium leprae, borderline lepromatous (BL) patients show clinical and immunological instability, and undergo frequent acute inflammatory episodes such as type 1 reaction (T1R), which may cause nerve damages. This work focused on the participation of T cell subsets from blood and skin at T1R onset. We observed a significantly increased ex vivo frequency of both effector and memory CD4+ and CD8+ T cells in T1R group.

Downregulation of PHEX in multibacillary leprosy patients: observational cross-sectional study.

Background: Peripheral nerve injury and bone lesions, well known leprosy complications, lead to deformities and incapacities. The phosphate-regulating gene with homologies to endopeptidase on the X chromosome (PHEX) encodes a homonymous protein (PHEX) implicated in bone metabolism. PHEX/PHEX alterations may result in bone and cartilage lesions.

Correlation between Central Memory T Cell Expression and Proinflammatory Cytokine Production with Clinical Presentation of Multibacillary Leprosy Relapse.

Background: Despite the efficacy of multidrug therapy, surviving Mycobacterium leprae causes relapse in some leprosy patients, and these patients present signs and symptoms of disease after healing. This study focused on the cellular immune response in relapsed multibacillary patients but also included non-relapsed multibacillary cured individuals, newly diagnosed and untreated multibacillary patients, paucibacillary patients just before the beginning of treatment, and voluntary healthy individuals for comparative analysis.

Methodology/principal Findings: Inhibition of CD86 expression in the blood-derived monocytes and dendritic cells of relapsed multibacillary patients, either ex vivo or after M.

Peptides Derived from Mycobacterium leprae ML1601c Discriminate between Leprosy Patients and Healthy Endemic Controls.

The stable incidence of new leprosy cases suggests that transmission of infection continues despite worldwide implementation of MDT. Thus, specific tools are needed to diagnose early stage Mycobacterium leprae infection, the likely sources of transmission. M.

Mycobacterium leprae downregulates the expression of PHEX in Schwann cells and osteoblasts.

Neuropathy and bone deformities, lifelong sequelae of leprosy that persist after treatment, result in significant impairment to patients and compromise their social rehabilitation. Phosphate-regulating gene with homologies to endopeptidase on the X chromosome (PHEX) is a Zn-metalloendopeptidase, which is abundantly expressed in osteoblasts and many other cell types, such as Schwann cells, and has been implicated in phosphate metabolism and X-linked rickets. Here, we demonstrate that Mycobacterium leprae stimulation downregulates PHEX transcription and protein expression in a human schwannoma cell line (ST88-14) and human osteoblast lineage.

The frequency of human papillomavirus findings in normal oral mucosa of healthy people by PCR.

Unlabelled: The human papillomavirus (HPV) is a DNA virus, which belongs to papillomaviridae family, being of low and high risk, which infect the skin and mucous membranes and can induce benign and malign tumor formation. In the oral mucosa they have been associated with oral papilloma, focal epithelial hyperplasia, leucoplakia and oral neoplasia.

Aim: to study the frequency of HPV finding in oral mucosa of normal people.

Clinical, immunological and histological aspects of an uncommon type II reaction in patients with lepromatous leprosy.

This study reports three cases of an unusual leprotic reaction characterized by superficial bullous ulcerative cutaneous lesions associated with high fever, malaise and oedema in patients with leprosy. Two patients responded to thalidomide treatment, with regression of the symptoms and skin ulcers. The third patient responded to thalidomide plus prednisone.

The influence of surface carbohydrates during in vitro infection of mammalian cells by the dermatophyte Trichophyton rubrum.

In order to better understand the role played by surface glycoconjugates during host cell adhesion and endocytosis of Trichophyton rubrum, we looked for the presence of carbohydrate-binding adhesins on the microconidia surface and their role on cellular interaction with epithelial and macrophages cells. The interaction of T. rubrum with chinese hamster ovary epithelial cells and their glycosylation-deficient mutants demonstrated a higher adhesion index in Lec1 and Lec2 mutants, that express mannose and galactose, respectively.

The effect of a catechin-rich extract of Cocos nucifera on lymphocytes proliferation.

Catechins are polyphenols with antioxidant activity. The fruit Cocos nucifera (Palmae) has a fi ber husk rich in catechins and the local population of northeast Brazil uses it as a medicine against various diseases. An anti-bacterial and anti-viral activity has been already observed using this substance.

Sialic acids are absent from the dermatophytes Trichophyton mentagrophytes and Trichophyton rubrum.

Experiments were performed to determine whether sialic acids are expressed in two dermatophytes: Trichophyton rubrum and T. mentagrophytes, similarly to other fungal pathogens. Chemical extraction of mycelia and microconidia followed by high-performance thin-layer chromatography and colorimetric assays were all negative for sialic acid.

The role of surface carbohydrates on the interaction of microconidia of Trichophyton mentagrophytes with epithelial cells.

The presence of carbohydrate-binding adhesins on the microconidia of Trichophyton mentagrophytes surface and their role on cellular interactions were investigated. Flow cytometry showed that this fungus recognizes the sugars mannose and galactose. The binding was inhibited by the addition of methyl alpha-D-mannopyranoside and methyl alpha-D-galactopyranoside, and showed higher fluorescence intensity at 37 degrees C than 28 degrees C.

Antimicrobial and antiviral activities of polyphenolics from Cocos nucifera Linn. (Palmae) husk fiber extract.

The decoction of Cocos nucifera L. husk fiber has been used in northeastern Brazil traditional medicine for treatment of diarrhea and arthritis. Water extract obtained from coconut husk fiber and fractions from adsorption chromatography revealed antimicrobial activity against Staphylococcus aureus.

Evaluation of B7-1 (CD80) and B7-2 (CD86) costimulatory molecules and dendritic cells on the immune response in leprosy.

The cell activation depends on T cell antigen receptor binding to antigen plus MHC and costimulation. The binding of CD28, expressed on the T cell surface to B7 (B7-1 or CD80/B7-2 or CD86) present on the antigen--presenting cells (APCs), determines, in several T cell function models, if activation or anergy follows antigenic stimulation. In leprosy, the role of CD80 and CD86 as costimulatory signal in M.

Evaluation of chemiluminescence, procoagulant activity and antigen presentation by monocytes from lepromatous leprosy patients with or without reactional episodes.

In this study, we evaluated the activity of peripheral blood mononuclear cells (PBMC), isolated from treated and untreated lepromatous leprosy patients, from lepromatous leprosy patients during and after reactional episodes (erythema nodosum leprosum (ENL) and reversal reaction (RR)), and from normal healthy individuals. We determined reactive oxygen intermediate (ROI) production, procoagulant activity (PCA) and HLA-DR antigen expression of monocytes, besides lymphoproliferation, both in the presence and absence of various stimulatory agents. Phorbol myristate acetate (PMA) stimulated ROI production by monocytes from all the groups studied, with patients during reactional episodes (ENL and RR) showing a significantly higher response (p < 0.

Effect of treatment on immune responsiveness in lepromatous leprosy patients.

This study was performed in order to analyse whether the immune unresponsiveness to Mycobacterium leprae, largely seen in lepromatous patients, persisted after discharge from treatment. Lymphoproliferation and skin tests were performed using two mycobacterial antigens (M. leprae and BCG) in three groups of lepromatous patients grouped by treatment status.

Characterization of tubulin genes in Trypanosoma rangeli.

Tubulin genes in Trypanosoma rangeli, the only trypanosome besides T. cruzi to infect humans in America, are organized in homogeneous, alternate alpha and beta gene tandem repeats of 3.8 kb.

Immunological responsiveness to M. leprae and BCG antigens in 98 leprosy patients and their household contacts.

1. The cellular immune response to M. leprae and BCG antigens was evaluated in 98 leprosy patients and 143 household contacts lacking clinical manifestation of the disease.