Morphine modulates gammadelta lymphocytes cytolytic activity following BCG vaccination

Morphine induces splenocyte trafficking into the CNS

Opioids significantly alter functional responses of lymphocytes following activation. The opiate Morphine, alters the Th1 to Th2 response and modulates functional responses such as cytolytic activity and T-cell proliferation. Although there has been extensive research involving morphine's effects on lymphocytes, little is known about the effects morphine has on lymphocyte trafficking. The objective of the study was to use in vivo bioluminescent imaging to determine morphine's effect on the trafficking pattern of splenocytes systemically and into the CNS either in a naïve state or following a neuroinflammatory stimulus. A neuroinflammatory response was induced by intracerebrally administering a DNA IFN-γ DNA plasmid into morphine-dependent or placebo wildtype mice. Mice with or without a neurostimulus received adoptively transferred firefly luciferase transgenic splenocytes and imaged. Morphine dependence significantly altered the inherent ability of splenocytes to traffic into the spleen, and lead to non-directed chaotic trafficking throughout the animal, including into the CNS. The morphine-mediated effects on trafficking were blocked by the antagonist naltrexone. Morphine dependence intensified splenocyte infiltration into the CNS following neuroinflammation induced by IFN-γ gene transfer. The study precented determined that morphine severely altered the ability of non-activated splenocytes to home to the spleen, inducing extrasplenic trafficking thoughout the animal. In addition to altering the ability of naive splenocyte to traffic to the spleen, this study demonstrated that morphine profoundly exacerbated lymphocyte infiltration into the CNS following a neurostimulus.

Intensive Care Unit-acquired infection as a side effect of sedation

Introduction

Sedative and analgesic medications are routinely used in mechanically ventilated patients. The aim of this review is to discus epidemiologic data that suggest a relationship between infection and sedation, to review available data for the potential causes and pathophysiology of this relationship, and to identify potential preventive measures.

Methods

Data for this review were identified through searches of PubMed, and from bibliographies of relevant articles.

Results

Several epidemiologic studies suggested a link between sedation and ICU-acquired infection. Prolongation of exposure to risk factors for infection, microaspiration, gastrointestinal motility disturbances, microcirculatory effects are main mechanisms by which sedation may favour infection in critically ill patients. Furthermore, experimental evidence coming from studies both in humans and animals suggest that sedatives and analgesics present immunomodulatory properties that might alter the immunologic response to exogenous stimuli. Clinical studies comparing different sedative agents do not provide evidence to recommend the use of a particular agent to reduce ICU-acquired infection rate. However, sedation strategies aiming to reduce the duration of mechanical ventilation, such as daily interruption of sedatives or nursing-implementing sedation protocol, should be promoted. In addition, the use of short acting opioids, propofol, and dexmedetomidine is associated with shorter duration of mechanical ventilation and ICU stay, and might be helpful in reducing ICU-acquired infection rates.

Conclusions

Prolongation of exposure to risk factors for infection, microaspiration, gastrointestinal motility disturbances, microcirculatory effects, and immunomodulatory effects are main mechanisms by which sedation may favour infection in critically ill patients. Future studies should compare the effect of different sedative agents, and the impact of progressive opioid discontinuation compared with abrupt discontinuation on ICU-acquired infection rates.

Endogenous opiates and behavior: 2007

This paper is the thirtieth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2007 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.

An update on the role of opioids in the management of chronic pain of nonmalignant origin

PURPOSE OF REVIEW

To summarize and reflect over primarily recent epidemiological and randomized controlled trials in opioid-treated chronic nonmalignant pain patients, focusing on effects, side effects, risks and long-term consequences of the treatment.

RECENT FINDINGS

In the western world opioids are increasingly being used for long-term treatment of chronic nonmalignant pain. While the long-term benefits of opioids regarding pain relief, functional capacity and health-related quality of life still remain to be proven, studies are emerging that describe serious long-term consequences such as addiction, opioid-induced hyperalgesia, cognitive disorders, and suppression of the immune and reproductive systems.

SUMMARY

Much more research is needed concerning long-time effects and consequences of opioid therapy in chronic nonmalignant pain patients; however, some clear warning signals have been sent out within recent years.

Passive transfer of maternal Mycoplasma hyopneumoniae-specific cellular immunity to piglets

Immunity in the neonatal animal is primarily maternally derived, either by lymphocytes that pass into the newborn across the placenta or following colostrum ingestion. However, the effect of this passively transferred cellular maternal immunity on the newborn's immune repertoire is not clearly understood. Various studies have shown that colostral lymphocytes are activated and possess functional abilities; however, no studies have shown the transfer of colostral antigen-specific T-cell-specific responses in a newborn. In this study we examined the transfer of vaccine-induced Mycoplasma hyopneumoniae cellular immunity from immune dams to newborn piglets. Newborn piglets from vaccinated and nonvaccinated dams were assessed in two ways for cellular immune responses specific to M. hyopneumoniae: (i) delayed-type hypersensitivity (DTH) testing and (ii) in vitro lymphocyte proliferation, assayed on piglet blood lymphocytes and sow colostral lymphocytes. DTH responses to M. hyopneumoniae were detected only for offspring of vaccinated sows, whereas DTH responses to the nonspecific mitogen phytohemagglutinin were seen for all piglets. M. hyopneumoniae-specific proliferation was seen for colostral lymphocytes from vaccinated sows and for blood lymphocytes from neonatal piglets of vaccinated dams but not for blood lymphocytes from piglets of nonvaccinated sows. Functional antigen-specific T cells were transferred to offspring from vaccinated sows and participated in the neonatal immune response upon stimulation. These data have implications for defining disease intervention strategies.

Brain behavior and immunity: twenty years of T cells

During the period from 1987 to 2007, our understanding of nervous system-T lymphocyte bi-directional communication advanced exponentially. Progress in exploring these relationships was aided by the constant development of new, cutting-edge technologies, and by a steady growth in interest, and number, of scientists who recognized the need to conduct cross-disciplinary research. In this brief review of 20 years of Brain, Behavior, and Immunity (BBI), we highlight just a small number of the important studies published in the journal that collectively have provided the foundation for our current understanding of brain, behavior, and, specifically, T cells.