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Although no precise moment or unique event marks its birth, neuroimmunoendocrinology arguably shares a great deal of history with other medical and biologic disciplines. It originated from empirical observations and suppositions that failed to prevail upon the existing axioms. Despite the widespread resistance to embracing novel ideas, the seeming defeats inspired visionary researchers. Those pioneers managed to systematize the emerging knowledge and were able to contribute to science with real foundations. In consequence, new concepts and ideas arose in physiology, anatomy, endocrinology and early immunology. Together, they gave rise to a budding approach on the integration between the nervous, immune and endocrine systems. Then, neuroimmunoendocrinology emerged as a discipline integrating an intricate system with multidirectional functions and interactions that allow for responding to internal and external threats. Such response is mediated by cytokines, hormones and neurotransmitters, involved in different physiologic mechanisms of the organism homeostasis. Neuroimmunoendocrinology is no longer an area of scientific skepticism; on the contrary, it has cemented its position as a biomedical discipline worldwide for the past 70 years. Now, it offers a better understanding of pathologic processes. [ABSTRACT FROM AUTHOR]

Background: Bovine tuberculosis (bTB) is still a prominent threat to animal health; lacking an efficient vaccine, other than BCG to get rid of tuberculosis, the most effective way for this is culling and slaughtering the infected animals. There are several cellular, serological, and molecular tests for the diagnosis of the disease but the most practical one at the field level is the double skin testing with bovine and aviary tuberculins. This is not a very specific test but is sensitive enough to identify most diseased animals; adjunct practical tests are desirable to strengthen the utility of skin tests. All lymphoid and myeloid cells participate, in diverse grades, in the immune response to tuberculosis with neutrophils playing an unintended pathologic role. The study aimed to investigate the response of neutrophils to agents present in the sera of tuberculous cows. Methods: We have developed a neutrophil-based test (N BT) to identify diseased cows within a herd suspected of having tuberculosis; a positive N BT correlates with a positive double skin test. In this test, healthy neutrophils are incubated with the sera of healthy or tuberculous cows for 3 and 6 h, and the nuclear morphologic changes are recorded and analyzed. Results: Sera from tuberculous but not from healthy cows induce nuclear alterations including pyknosis, swelling, apoptosis, and sometimes NETosis, in healthy neutrophils, and CFP 10 and ESAT 6 participate in the phenomenon. Conclusion: We propose the N BT as an auxiliary tool for substantiating the diagnosis of bTB reinforcing the PPD test outcome to help decide whether or not a cow should be sacrificed. [ABSTRACT FROM AUTHOR]

Host immunity to Mycobacterium leprae encompasses a spectrum of mechanisms that range from cellular immunity-driven protection to damage associated with humoral immunity as in type-2 leprosy reactions. Although type I interferons (IFNs) participate in eliminating intracellular pathogens, their contribution to the production of antibodies and CD3+ FOXP3+ regulatory T cells (Tregs) in BCG vaccine-mediated protection in leprosy is unknown. BCGphipps (BCGph) priming followed by intramuscular hIFN-α 2b boost significantly reduced lesion size and Mycobacterium lepraemurium growth in the skin. T follicular regulatory cells (TFR), a subset of Tregs induced by immunization or infection, reside in the germinal centers (GCs) and modulate antibody production. We found impaired Treg induction and improved GCs in draining lymph nodes of BCGph primed and hIFN-α 2b boosted mice. Moreover, these mice elicited significant amounts of IL-4 and IL-10 in serum. Thus, our results support the adjuvant properties of hIFN-α 2b in the context of BCGph priming to enhance protective immunity against skin leprosy. [ABSTRACT FROM AUTHOR]

Background: It has been reported that sera from patients with active pulmonary tuberculosis (APT) induced nuclear changes in normal neutrophils that included pyknosis, swelling, apoptosis, and production of extracellular traps (NETs). Similar changes were observed with some sera from their household contacts but not with sera from healthy, unrelated individuals. It was suggested that those sera from household contacts that induced neutrophil nuclear changes might correspond to people with subclinical tuberculosis. Thus, our experimental approach might serve to identify individuals with early, ongoing disease. Methods: Nuclear changes in neutrophils were fully evident by 3 h of contact and beyond. Circulating mycobacterial antigens were the most likely candidates for this effect. We wanted to know whether the nuclear changes induced on neutrophils by the sera of APT patients would negatively affect the phagocytic/microbicidal ability of neutrophils exposed to APT sera for short periods. Results: We now provide evidence that short-term contact (30 min) with sera from patients with pulmonary tuberculosis increases several phagocytic parameters of normal neutrophils, including endocytosis, myeloperoxidase levels, production of free reactive oxygen species, phagolysosome fusion, and microbicidal activity on Staphylococcus aureus, with these effects not being observed with sera from healthy donors. We also give evidence that suggests that ESAT-6 and CFP-10 are involved in the phenomenon. Conclusion: We conclude that activation is a stage that precedes lethal nuclear changes in neutrophils and suggests that autologous neutrophils must circulate in an altered state in the APT patients, thus contributing to the pathology of the disease. [ABSTRACT FROM AUTHOR]

Background: Murine leprosy is a chronic granulomatous disease caused by Mycobacterium lepraemurium (MLM) in mice and rats. The disease evolves with the development of cellular anergy that impedes the production of interferon gamma (IFNγ), tumor necrosis factor-alpha (TNFα), and nitric oxide (NO) required to kill the microorganism. In this study we investigated whether histone deacetylase inhibitors (HDACi) (valproic acid and sodium butyrate [NaB]) and the immunomodulator transfer factor in dialyzable leukocyte extracts (DLE) can prevent anergy in murine leprosy. Methods: Five groups of six Balb/c mice were intraperitoneally inoculated with 2 × 107 MLM. Thirty-days post inoculation, treatment was started; one group received no treatment, one was treated with rifampicin-clofazimine (R-C), one with sodium valproate (VPA), one with NaB, and one with DLE. The animals were monitored for the evidence of disease for 96 days. After euthanasia, their spleens were removed and processed for histologic, bacteriologic, and cytokine studies. Results: R-C completely controlled the ongoing disease. DLE and NaB significantly reduced the development of lesions, including granuloma size and the number of bacilli; VPA was less effective. DLE, NaB, and VPA reverted the anergic condition in diverse grades and allowed the expression of IFNγ, TNFα, and inducible NO synthase, also in diverse grades. Conclusion: Anergy in leprosy and murine leprosy allows disease progression. In this study, anergy was prevented, in significant degree, by DLE (an immunomodulator) and NaB (HDACi). VPA was less effective. These results suggest potential beneficial effects of DLE and NaB in the ancillary treatment of leprosy. [ABSTRACT FROM AUTHOR]

Summary: Rheumatoid arthritis is a disabling autoimmune disease with a high global prevalence. Treatment with disease‐modifying anti‐arthritic drugs (DIMARDs) has been routinely used with beneficial effects but with adverse long‐term consequences; novel targeted biologics and small‐molecule inhibitors are promising options. In this study, we investigated whether purified omega unsaturated fatty acids (ω‐UFAs) and dialysable leukocyte extracts (DLEs) prevented the development of arthritis in a model of collagen‐induced arthritis (CIA) in mice. We also investigated whether the transcription factor NF‐κB and the NLRP3 inflammasome were involved in the process and whether their activity was modulated by treatment. The development of arthritis was evaluated for 84 days following treatment with nothing, dexamethasone, DLEs, docosahexaenoic acid, arachidonic acid, and oleic acid. Progression of CIA was monitored by evaluating clinical manifestations, inflammatory changes, and histological alterations in the pads' articular tissues. Both DLEs and ω‐UFAs led to an almost complete inhibition of the inflammatory histopathology of CIA and this was concomitant with the inhibition of NF‐kB and the inhibition of the activation of NLRP3. These data suggest that ω‐UFAs and DLEs might have NF‐κB as a common target and that they might be used as ancillary medicines in the treatment of arthritis. [ABSTRACT FROM AUTHOR]

Background: Resident alveolar macrophages, dendritic cells, and immigrating neutrophils (NEU) are the first cells to contact Mycobacterium tuberculosis in the lung. These cells, and additional lymphoid cells in the developing granuloma, release a series of components that may concentrate in the serum and affect disease progression. Purpose: The aim of this study was to investigate the effect of the serum from tuberculosis (TB) patients and their household contacts (HHC) on the nuclear morphology of NEU. Materials and methods: NEU from healthy (HLT) people were incubated with sera from patients with active pulmonary TB, their HHC, and unrelated people. Changes in the nuclear morphology of NEU were analyzed by light and electron microscopy. Results: Sera from patients with TB induced changes in the nuclear morphology of NEU that included pyknosis, swelling, apoptosis, and netosis in some cases. Sera from some HHC induced similar changes, while sera from HLT people had no significant effects. Bacteria did not appear to participate in this phenomenon because bacteremia is not a recognized feature of nonmiliary TB, and because sera from patients that induced nuclear changes maintained their effect after filtration through 0.22 µm membranes. Neither anti-mycobacterial antibodies, TNFα, IL-6, IFNγ, or IL-8 participated in the phenomenon. In contrast, soluble mycobacterial antigens were likely candidates, as small quantities of soluble M. tuberculosis antigens added to the sera of HLT people led to the induction of nuclear changes in NEU in a dose-dependent manner. Conclusion: These results might help to detect subclinical TB within HHC, thus leading to a recommendation of prophylactic treatment. [ABSTRACT FROM AUTHOR]

In 2004, a novel mechanism of cellular death, called 'NETosis', was described in neutrophils. This mechanism, different from necrosis and apoptosis, is characterized by the release of chromatin webs admixed with microbicidal granular proteins and peptides (NETs). NETs trap and kill a variety of microorganisms. Diverse microorganisms, including Mycobacterium tuberculosis, are NET inducers in vitro. The aim of this study was to examine whether M. tuberculosis can also induce NETs in vivo and if the NETs are bactericidal to the microorganism. Guinea pigs were intradermally inoculated with M. tuberculosis H37Rv, and the production of NETs was investigated at several time points thereafter. NETs were detected as early as 30 min post-inoculation and were clearly evident by 4 h post-inoculation. NETs produced in vivo contained DNA, myeloperoxidase, elastase, histones, ROS and acid-fast bacilli. Viable and heat-killed M. tuberculosis, as well as Mycobacterium bovis BCG were efficient NET inducers, as were unilamellar liposomes prepared with lipids from M. tuberculosis. In vitro, guinea pig neutrophils also produced NETs in response to M. tuberculosis. However, neither the in vivo nor the in vitro-produced NETs were able to kill M. tuberculosis. Nevertheless, in vivo, neutrophils might propitiate recruitment and activation of more efficient microbicidal cells. [ABSTRACT FROM AUTHOR]

Objective/Background: Mycobacterium lepraemurium (MLM), the etiologic agent of murine leprosy, is an intracellular parasite of macrophages; the mechanism used by this bacterium to enter macrophages is not known. The fate of the MLM phagosome inside macrophages is also unknown. This study was conducted to investigate how MLM enters macrophages and to deine the maturation process of MLM phagosome inside macrophages. Materials and Methods: Peritoneal macrophages were incubated in the presence of mannan--bovine serum albumin (BSA), and antibodies to known macrophage receptors, including, anti-FcγRIII/RII (anti-CD16/32), anti-CD35 (anti-CR1), anti-TLR2, anti-TLR4, anti-TLR6, anti-CD14, and anti-dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN). Then, macrophages were challenged with Iris Fuchsia-stained MLM, at a multiplicity of infection of 50:1. The blocking effect of the antibodies (and mannan--BSA) used was analyzed using direct microscopy and low cytometry. The maturation process of MLM phagosomes was visualized by their interaction with antibodies to Rab5, Rab7, proton ATPase, and cathepsin D, by confocal microscopy. Results: Only mannan--BSA and anti-TLR6 antibody signiicantly blocked the entry of MLM into macrophages. None of the other antibodies, including that for DC-SIGN, meaningfully inhibited the endocytic process. We also found that MLM is a fusiogenic mycobacterium. This was deduced from the orderly association of MLM phagosomes with Rab5, Rab7, Proton ATPase, and lysosomes (cathepsin D). Conclusion: Fusion of MLM phagosomes with lysosomes seems to be a necessary event for the intracellular multiplication of MLM; similar to Mycobacterium leprae, this microorganism hardly grows on artiicial, synthetic, bacteriologic media. [ABSTRACT FROM AUTHOR]

Objectives: Neutrophils play an important role in the control of pathogens through several mechanisms, including phagocytosis and the formation of neutrophil extracellular traps (NETs). The latter consists of DNA as a backbone with embedded antimicrobial peptides, histones, and proteases, providing a matrix to entrap and in some cases to kill microbes. Some metabolic requirements for NET formation have recently been described. The virus-induced formation of NETs and the role of these traps in viral infections remain scarcely reported. Here, we analyzed whether dengue virus serotype-2 (DENV-2) induces NET formation and the DENV-2 effect on phorbol myristate acetate (PMA)-induced NETs. Methods: Peripheral blood-derived neutrophils were exposed in vitro to DENV-2 or exposed to DENV-2 and then stimulated with PMA. NET formation was assessed by fluorescence microscopy. Cell membrane Glut-1, glucose uptake, and reactive oxygen species (ROS) production were assessed. Results: DENV-2 does not induce the formation of NETs. Moreover, DENV-2 inhibits PMA-induced formation of NETs by about 80%. This effect is not related to the production of ROS. The mechanism seemingly accountable for this inhibitory effect is the DENV-2-mediated inhibition of PMA-induced glucose uptake by neutrophils. Conclusion: Our results suggest that DENV-2 inhibits glucose uptake as a metabolism-based way to avoid the formation of NETs. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Background: Myeloperoxidase (MPO), in the presence of hydrogen peroxide and a halide represent an efficient microbicidal mechanism of phagocytic cells. MPO is abundant in neutrophils which also respond to infection by producing large amounts of reactive oxygen species (ROS). MPO, ROS and halide constitute a very toxic antimicrobial system (called the Klebanoff system or KS). Resting mature macrophages do not contain granular MPO and thus are unable to kill pathogenic mycobacteria and some other microorganisms by this system. Experimental: Under the hypothesis that transforming macrophages into peroxidase-positive (PO+) cells, these cells would be able to kill Mycobacterium tuberculosis, in this study, mature macrophages were loaded with exogenous peroxidase and were tested for their capacity to kill the Mycobacterium in the presence or in the absence of hydrogen peroxide. Results: It was found that PO-loaded macrophages eagerly ingest M. tuberculosis, but do not show a significant mycobactericidal activity on this microorganism despite that it is highly susceptible to the Klebanoff system in vitro. Failure of PO-loaded macrophages to kill M. tuberculosis may obey either to an inappropriate location of the exogenous PO in these cells or more likely, to the presence of efficient detoxifying mechanisms in the bacteria. On the contrary, MPO-loaded or unloaded macrophages efficiently killed Listeria monocytogenes. Conclusion: The lack of granular MPO in mature macrophages, and the predilection of mycobacteria to infect these cells are two situations that favor the development of tuberculosis and related diseases, such as leprosy and Buruli ulcer. [Copyright &y& Elsevier]

Soybean is a source of high-quality proteins and fatty acids for animal and human nutrition. To satisfy the national demand of this crop it is necessary to increase the production of soybean by developing or selecting species that are resistant to adverse environmental conditions. Four soybean varieties customarily grown in Mexico were studied in a comparative manner. Each variety was characterized on the basis of impurities, grain integrity, water content, total and free fatty acids content, protein content, and germination capability following the methods and regulations indicated in NMX-FF-089-1994-SCFI, ISTA and AOAC. None of the soybean varieties presented impurities; Huasteca-100 soybean had a lower percentage of immature grains while the UFV-1 variety had the lowest number of grains damaged by microorganisms. Humidity contents were similar in all four soybean varieties (around 7%). The Huasteca-100 variety had some lower protein content while the UFV-1 variety had the maximum (39%). On the contrary, the lipid content was higher in Huasteca-100 and lower in the UFV-1 variety. Based on these results and on the fact that Huasteca 100 was a strong prospect for massive cultivation in Mexico, this variety was considered an adequate substrate to further study the effect of diverse stressing conditions. [ABSTRACT FROM AUTHOR]

Summary: Due to the intracellular nature of mycobacterial infections, little attention has been paid to the possible extracellular role that neutrophils might play in tuberculosis. The recent discovery of neutrophil extracellular traps (NETs), composed of DNA and antimicrobial proteins,1 introduces a new perspective to our understanding of the mechanism used by the innate immune system to contain and kill microorganisms. In this study, we tested in vitro whether Mycobacterium tuberculosis, an intracellular pathogen, can induce NETs formation and if this newly discovered mechanism is involved in a control response during mycobacterial infection. We found that two different genotypes of M. tuberculosis exerted, in vitro, a cytotoxic effect and induced subcellular changes on infected neutrophils, leading to NETs formation in a time dependent manner. NETs trapped mycobacteria but were unable to kill them. NETs formation induced by M. tuberculosis could help understand the early stages of mycobacterial pathogenesis. [Copyright &y& Elsevier]

Mycobacterium lepraemurium is the causative agent of murine leprosy, a chronic, granulomatous disease similar to human leprosy. Due to the similar clinical manifestations of human and murine leprosy and the difficulty of growing both bacilli axenically, Mycobacterium leprae and M. lepraemurium were once thought to be closely related, although it was later suggested that M. lepraemurium might be related to Mycobacterium avium In this study, the complete genome of M. lepraemurium was sequenced using a combination of PacBio and Illumina sequencing. Phylogenomic analyses confirmed that M. lepraemurium is a distinct species within the M. avium complex (MAC). The M. lepraemurium genome is 4.05 Mb in length, which is considerably smaller than other MAC genomes, and it comprises 2,682 functional genes and 1,139 pseudogenes, which indicates that M. lepraemurium has undergone genome reduction. An error-prone repair homologue of the DNA polymerase III α-subunit was found to be nonfunctional in M. lepraemurium , which might contribute to pseudogene formation due to the accumulation of mutations in nonessential genes. M. lepraemurium has retained the functionality of several genes thought to influence virulence among members of the MAC. IMPORTANCE Mycobacterium lepraemurium seems to be evolving toward a minimal set of genes required for an obligatory intracellular lifestyle within its host, a niche seldom adopted by most mycobacteria, as they are free-living. M. lepraemurium could be used as a model to elucidate functions of genes shared with other members of the MAC. Its reduced gene set can be exploited for studying the essentiality of genes in related pathogenic species, which might lead to discovery of common virulence factors or clarify host-pathogen interactions. M. lepraemurium can be cultivated in vitro only under specific conditions and even then with difficulty. Elucidating the metabolic (in)capabilities of M. lepraemurium will help develop suitable axenic media and facilitate genetic studies., (Copyright © 2017 Benjak et al.)

Background: Discoid lupus erythematosus (DLE) is a cutaneous autoimmune inflammatory disease in which the role of conventional dendritic cells (cDCs) in skin damage has not been evaluated., Objective: To evaluate the involvement of cDCs in DLE pathogenesis., Material & Methods: Skin biopsies from 42 patients with DLE were embedded in paraffin or placed in culture. The dermis was separated and cell suspensions were characterized by flow cytometry., Results: We found an increase in cDCs with inflammatory characteristics in the skin of DLE patients, compared with control skins. Interestingly, cDCs from the DLE patients expressed low levels of the inhibitory molecule PD-L1 and showed a high expression of CCR6, which correlated with disease activity. Increased cellular death was observed in the skin of DLE patients compared with control skin and remarkably we found that damage-associated molecular patterns could be responsible for CCR6 expression on cDCs in the skin., Conclusions: Our results indicate the presence of pathogenic CCR6+ cDCs in the skin lesions of DLE patients, which could result from in situ phenotypic changes.

Background: The phagocytic function in pulmonary tuberculosis (PTB) and Type 2 diabetes (T2D) has been explored mainly in macrophages but not in polymorphonuclears (PMN). The purpose of this study was to determine the functional status of PMN leukocytes in patients with pulmonary tuberculosis (PTB), Type 2 diabetes (T2D), and in patients with both diseases., Methods: An observational, prospective, and comparative study was carried out. 30 ambulatory patients with T2D, 10 with PTB undergoing treatment and 10 patients with PTB and T2D, and 44 healthy subjects were studied. PMN leukocytes were separated, the capacity of these cells to produce hydrogen peroxide and to reduce nitroblue tetrazolium (NBT) in response to stimulus with the phorbolic ester of myristic acid (PMA) was measured; and the capacity of PMN leukocytes to adhere to surfaces was determined., Results: Concerning the test for adherence, on comparing healthy subjects with patients with T2D+PTB, we observed a clear decrease in cellular adherence in the group of patients with both diseases; it was statistically significant (p = 0.007).With regard to phagocytic function, we observed that in NBT reduction as well as in hydrogen peroxide production, statistically significant differences were not obtained on comparing healthy subjects with any of the three groups of patients., Conclusions: We observed a clear decrease in cellular adherence when both diseases co-exist. These results could indicate the need for the co-existence of T2D and TB to cause deterioration in the cells' adherence activity. The microtechniques employed permit the evaluation in a practical manner of certain phagocytic-activity expressions.

Mycobacterium lepraemurium (MLM) is a successful parasite of murine macrophages; in vitro, this microorganism infects macrophages without triggering these cells' ability to produce either the reactive oxygen intermediaries (ROI) or the reactive nitrogen intermediaries (RNI), and ends up lodging within these cells, that, in addition, do not contain myeloperoxidase (MPO). In this study, we analyzed the effect of exogenous peroxidase on the evolution of murine leprosy. Bacilli were intraperitoneally injected, either alone (MLM) or precoated with horseradish peroxidase (MLM-PO), into two different groups of mice. At two-week intervals, the groups were blood-sampled to measure the levels of antibodies to protein- or lipid-MLM antigens. The extent of the disease was also assessed by looking at the histopathologic changes that occurred both in the liver and the spleen of the infected animals. We found that the animals injected with MLM-PO developed a disease that evolved at a slower pace than the disease that occurred in the animals injected with intact MLM. The difference between groups, both in terms of antibody levels and histological changes, was clearly evident at the intermediate stages of the disease (2 to 2.5 months), but was not so obvious at the more advanced stage of 3 months. Several possibilities to explain how the PO-coated bacilli might have regained their infectiousness are discussed. Lowering the infective dose of MLM and MLM-PO from 5 x 10(7) bacilli to 5 x 10(6) bacilli would, probably, have resulted in a different outcome of the disease: more extended in the MLM-group than in the MLM-PO group.

Pathogenic mycobacteria must possess efficient survival mechanisms to resist the harsh conditions of the intraphagosomal milieu. In this sense, Mycobacterium lepraemurium (MLM) is one of the most evolved intracellular parasites of murine macrophages; this microorganism has developed a series of properties that allows it not only to resist, but also to multiply within the inhospitable environment of the phagolysosome. Inside the macrophages, MLM appears surrounded by a thick lipid-envelope that protects the microorganism from the digestive effect of the phagosomal hydrolases and the acid pH. MLM produces a disease in which the loss of specific cell-mediated immunity ensues, thus preventing activation of macrophages. In vitro, and possibly also in vivo, MLM infects macrophages without triggering the oxidative (respiratory burst) response of these cells, thus preventing the production of the toxic reactive oxygen intermediaries (ROI). Supporting the idea that MLM is within the most evolved pathogenic microorganisms, in the present study we found, that contrary to BCG, M. lepraemurium infects macrophages without stimulating these cells to produce meaningful levels of tumor necrosis factor alpha (TNF alpha) or nitric oxide (NO). Thus, the ability of the microorganisms to stimulate in their cellular hosts, the production of ROI and RNI (reactive nitrogen intermediates), seems to be an inverse correlate of their pathogenicity; the lesser their ability, the greater their pathogenicity.