Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0026918 (Mycobacterium)
 52,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mycobacterium avium ssp. paratuberculosis (MAP) infection in cattle causes significant economic losses to the dairy and beef industries resulting from reduced productivity, premature culling and mortality. Bovine Dectin-1, an important pattern recognition molecule that is able to generate a proinflammatory response by acting alongside Toll like receptor (TLR) signaling, is known to co-operate with TLR2 to specifically activate a macrophage proinflammatory response against mycobacterial infections. Therefore, the goal of this study was to identify single nucleotide polymorphisms (SNPs) in the gene encoding bovine Dectin-1 (CLEC7A) and to assess their association with susceptibility to MAP infection in dairy cattle. Blood and milk samples, collected from commercial dairy operations, were tested for MAP infection using blood and milk ELISAs and a resource population consisting of 197 infected and 242 healthy cattle was constructed. Pooled DNA was used for sequencing and eight single nucleotide polymorphisms (SNPs) were identified. Identified SNPs were genotyped on the resource population using the iPLEX MassARRAY system and statistical analysis was performed using logistic regression fitting the additive and dominance effects of each SNP in the model. Out of a total of eight identified SNPs, five were successfully genotyped, and three out of these five SNPs were found to be in complete linkage. Statistical analysis revealed a strong association between a non-synonymous SNP c.589A>G (p=0.008), and MAP infection status of the resource population inferred by seropositivity in MAP antibody specific ELISAs. This SNP c.589A>G was located in the geneic region that encodes the carbohydrate recognition domain of bovine Dectin-1. Therefore, further investigation of its functional relevance is warranted.
 ...
PMID:Bovine CLEC7A genetic variants and their association with seropositivity in Johne's disease ELISA. 2439 10

DC-SIGN (CD209/CLEC4L) is a C-type lectin receptor (CLR) that serves as a reliable cell-surface marker of interleukin 4 (IL-4)-activated human macrophages [M(IL-4)], which historically represent the most studied subset within the M2 spectrum of macrophage activation. Although DC-SIGN plays important roles in Mycobacterium tuberculosis (Mtb) interactions with dendritic cells, its contribution to the Mtb-macrophage interaction remains poorly understood. Since high levels of IL-4 are correlated with tuberculosis (TB) susceptibility and progression, we investigated the role of DC-SIGN in M(IL-4) macrophages in the TB context. First, we demonstrate that DC-SIGN expression is present both in CD68+ macrophages found in tuberculous pulmonary lesions of non-human primates, and in the CD14+ cell population isolated from pleural effusions obtained from TB patients (TB-PE). Likewise, we show that DC-SIGN expression is accentuated in M(IL-4) macrophages derived from peripheral blood CD14+ monocytes isolated from TB patients, or in macrophages stimulated with acellular TB-PE, arguing for the pertinence of DC-SIGN-expressing macrophages in TB. Second, using a siRNA-mediated gene silencing approach, we performed a transcriptomic analysis of DC-SIGN-depleted M(IL-4) macrophages and revealed the upregulation of pro-inflammatory signals in response to challenge with Mtb, as compared to control cells. This pro-inflammatory gene signature was confirmed by RT-qPCR, cytokine/chemokine-based protein array, and ELISA analyses. We also found that inactivation of DC-SIGN renders M(IL-4) macrophages less permissive to Mtb intracellular growth compared to control cells, despite the equal level of bacteria uptake. Last, at the molecular level, we show that DC-SIGN interferes negatively with the pro-inflammatory response and control of Mtb intracellular growth mediated by another CLR, Dectin-1 (CLEC7A). Collectively, this study highlights a dual role for DC-SIGN as, on the one hand, being a host factor granting advantage for Mtb to parasitize macrophages and, on the other hand, representing a molecular switch to turn off the pro-inflammatory response in these cells to prevent potential immunopathology associated to TB.
 ...
PMID:The C-Type Lectin Receptor DC-SIGN Has an Anti-Inflammatory Role in Human M(IL-4) Macrophages in Response to Mycobacterium tuberculosis. 2994 17

The aim of this study was to identify the single-nucleotide polymorphisms (SNPs) in bovine candidate genes CLEC7A, CD209 and TLR4, and explore the association between these SNPs with the occurrence of bovine paratuberculosis (PTB) disease. For this purpose, 549 animals were screened by a panel of four diagnostic tests, namely Johnin PPD test, ELISA test, faecal microscopy and IS900 blood PCR against Mycobacterium avium ssp. paratuberculosis (MAP) to develop case-control populations. SNPs were genotyped by polymerase chain reaction-restriction fragment length polymorphism method. Genotypic-phenotypic associations were assessed by the PROCLOGISTIC procedure of SAS 9.3. Of the seven SNPs; rs110353594 in CLEC7A gene and rs8193046 in TLR4 gene were found to be associated with PTB. For SNP rs110353594, odds of CC and CT genotypes vs TT genotype was 1.543 (0.420-5.667; 95% CI) and 0.284 (0.104-0.774; 95% CI), respectively which means that CT genotype was more resistant than TT and CC genotypes against bovine PTB. For SNP rs8193046, odds of AA and AG genotypes versus GG genotype was 0.947 (0.296-3.034; 95% CI) and 3.947 (1.555-10.022; 95% CI), respectively, i.e. probability for getting an infection in animals with AG genotype was 3.94 times more as compared to GG genotype. Hence, a selection programme favouring CT genotype for rs110353594 and against AG genotype for rs8193046 may be beneficial for conferring resistance against bovine PTB.
 ...
PMID:Single-nucleotide polymorphisms in CLEC7A, CD209 and TLR4 gene and their association with susceptibility to paratuberculosis in Indian cattle. 3236 37