IL-17 and γδ T-lymphocytes play a critical role in innate immunity against Nocardia asteroides GUH-2.

The early host response during pulmonary nocardiosis is highly dependent on neutrophils and the successful clearance of bacteria in tissue. The data presented in this study showed that IL-17 mediated the neutrophil response following intranasal inoculation with Nocardia asteroides strain GUH-2. Flow cytometry revealed that neutrophil levels in C57BL/6 mice were increased by day 1 post inoculation and remained elevated until day 3, during which time the majority of bacterial clearance occurred.

An unusual murine behavior following infection with log-phase Nocardia asteroides type 6 strain GUH-2 (Nocardia cyriacigeorgica GUH-2).

Nocardia asteroides (Nocardia cyriacigeorgica) strain GUH-2 infects the brains of mice following intravenous injection. Non-lethal infections resulted in a transitory increase of bacterial numbers in the brain followed by the development of permanent impaired movements at a time when bacteria appeared to be eliminated from the brain. These signs included headshake, rigidity, stooped posture, dyskinesia, retropulsion, and abnormal tail positioning in approximately 20% of infected animals.

Nocardia asteroides strain GUH-2 induces proteasome inhibition and apoptotic death of cultured cells.

Many bacterial pathogens have the ability to induce apoptosis in their hosts. It was previously shown that Nocardia asteroides strain GUH-2, a Gram-positive facultatively intracellular pathogen, is capable of inducing the apoptotic death of dopaminergic cells in the murine brain and in PC12 cells, a rat cell line. In this study, the apoptosis-inducing potential of N.

Modulation of eukaryotic cell apoptosis by members of the bacterial order Actinomycetales.

Apoptosis, or programmed cell death, is normally responsible for the orderly elimination of aged or damaged cells, and is a necessary part of the homeostasis and development of multicellular organisms. Some pathogenic bacteria can disrupt this process by triggering excess apoptosis or by preventing it when appropriate. Either event can lead to disease.

Comparison of PCR and culture for detection of Nocardia asteroides in brain specimens from experimentally infected BALB/c mice.

Systemic infection of BALB/c mice with Nocardia asteroides strain GUH-2 results in widespread replication of the organism in the brain, followed by its immune-mediated clearance. The present study compared the sensitivity of polymerase chain reaction (PCR) to bacterial culture for detection of cerebral nocardial infection in this experimental system. Mice (n=4/time point) were administered N.

Characterization of dopamine-depleting activity of Nocardia asteroides strain GUH-2 culture filtrate on PC12 cells.

Experimental infection of BALB/c mice with the Gram-positive bacterium Nocardia asteroides (strain GUH-2) results in life-long movement abnormalities including head shaking and spinning when held by the tail. The head shaking is temporarily inhibited by treatment with dopamine's precursor levodopa, suggesting that abnormalities in dopaminergic neurotransmission may be involved in these movement abnormalities. Cell-free filtrates from N.

Interferon-gamma activation of polymorphonuclear neutrophil function.

As current research illuminates the dynamic interplay between the innate and acquired immune responses, the interaction and communication between these two arms has yet to be fully investigated. Polymorphonuclear neutrophils (PMNs) and interferon-gamma (IFN-gamma) are known critical components of innate and acquired immunity, respectively. However, recent studies have demonstrated that these two components are not entirely isolated.

In situ hybridization for detection of nocardial 16S rRNA: reactivity within intracellular inclusions in experimentally infected cynomolgus monkeys--and in Lewy body-containing human brain specimens.

Our previous studies found that experimental infection of BALB/c mice with the Gram-positive bacterium Nocardia asteroides induced a parkinsonian-type syndrome with levodopa-responsive movement abnormalities, loss of nigrostriatal dopaminergic neurons, depletion of striatal dopamine, and intraneuronal inclusions in the substantia nigra (SN) with an appearance similar to Lewy bodies. In the present study, an in situ hybridization technique was developed to detect nocardial 16S ribosomal RNA (rRNA), using a Nocardia-specific probe (B77). Cerebral cortical specimens from cynomolgus monkeys were examined for the presence of nocardial RNA 48 h, 3.

Nocardia asteroides culture filtrates cause dopamine depletion and cytotoxicity in PC12 cells.

Experimental infection of BALB/c mice with the gram-positive bacterium Nocardia asteroides produces marked loss of nigrostriatal dopamine neurons, resulting in striatal dopamine depletion. To investigate the mechanism(s) responsible for this neuronal loss, we evaluated the influence of N. asteroides cell-free culture filtrates on rat pheochromocytoma PC12 cells, an in vitro model for dopamine neurons.

Successful management of disseminated Nocardia transvalensis infection in a heart transplant recipient after development of sulfonamide resistance: case report and review.

Nocardia transvalensis is a rarely reported cause of clinically significant disease, and, to our knowledge, has not been reported previously as a cause of infection in the cardiac transplant population. We report a case of N transvalensis new taxon-2 pulmonary infection that disseminated to the brain and skin in a cardiac transplant recipient despite adequate sulfonamide serum levels. Subsequent isolates were resistant to sulfonamides, and molecular ribotyping of the primary and subsequent isolates confirmed that these were the same N transvalensis new taxon-2 strain.

Murine polymorphonuclear neutrophils produce interferon-gamma in response to pulmonary infection with Nocardia asteroides.

Nocardia asteroides causes an acute, necrotizing pneumonia characterized by extensive infiltration of polymorphonuclear neutrophils (PMNs) into the lungs. Although PMNs have historically been classified as end-point cells, recent investigations have indicated that PMNs have the ability to secrete cytokines such as interleukin (IL)-4 and IL-12. This study investigated the ability of PMNs to produce cytokines in a murine model of N.

Captive rhesus monkeys (Macaca mulatta) are commonly infected with Helicobacter cinaedi.

Helicobacter cinaedi may cause proctocolitis or bacteremia in homosexual men infected with human immunodeficiency virus or occasionally in other immunocompromised hosts. There are scattered reports of H. cinaedi isolated from a variety of animal hosts, but to date only hamsters have been found to be a common natural reservoir.