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Differential effects of gram-positive and gram-negative bacterial products on morphine induced inhibition of phagocytosis.

ABSTRACT: Opioid drug abusers have a greater susceptibility to gram positive (Gram (+)) bacterial infections. However, the mechanism underlying opioid modulation of Gram (+) versus Gram (-) bacterial clearance has not been investigated. In this study, we show that opioid treatment resulted in reduced phagocytosis of Gram (+), when compared to Gram (-) bacteria. We further established that LPS priming of chronic morphine treated macrophages leads to potentiated phagocytosis and killing of both Gram (+) and Gram (-) bacteria in a P-38 MAP kinase dependent signaling pathway. In contrast, LTA priming lead to inhibition of both phagocytosis and bacterial killing. This study demonstrates for the first time the differential effects of TLR4 and TLR2 agonists on morphine induced inhibition of phagocytosis. Our results suggest that the incidence and severity of secondary infections with Gram (+) bacteria would be higher in opioid abusers.

SUBMITTER: Ninkovic J

PROVIDER: S-EPMC4759540 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Differential effects of gram-positive and gram-negative bacterial products on morphine induced inhibition of phagocytosis.

Ninkovic Jana J Anand Vidhu V Dutta Raini R Zhang Li L Saluja Anuj A Meng Jingjing J Koodie Lisa L Banerjee Santanu S Roy Sabita S

Scientific reports 20160219

Opioid drug abusers have a greater susceptibility to gram positive (Gram (+)) bacterial infections. However, the mechanism underlying opioid modulation of Gram (+) versus Gram (-) bacterial clearance has not been investigated. In this study, we show that opioid treatment resulted in reduced phagocytosis of Gram (+), when compared to Gram (-) bacteria. We further established that LPS priming of chronic morphine treated macrophages leads to potentiated phagocytosis and killing of both Gram (+) and ...[more]

PMID: 26891899

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Differential effects of gram-positive and gram-negative bacterial products on morphine induced inhibition of phagocytosis.

Publications

Differential effects of gram-positive and gram-negative bacterial products on morphine induced inhibition of phagocytosis.

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