Release of prostaglandin E2 and leukotriene B4 by alveolar macrophages from patients with sarcoidosis

Molecular Association of Medulloblastoma and Sarcoidosis: Case Report and Review of the Literature

BACKGROUND

Medulloblastoma (MB) is a malignant tumor of the central nervous system (CNS), and sarcoidosis is a chronic inflammatory disease of many organ systems, commonly affecting the lungs. No association between MB and sarcoidosis was described in the literature. MB and sarcoidosis have mutual molecular and signaling pathways that may predispose patients with sarcoidosis to develop MB. We describe a patient with sarcoidosis who developed MB.

CASE DESCRIPTION

The patient is a 36-year-old diagnosed with pulmonary sarcoidosis presented with ataxia, bilateral horizontal nystagmus, diplopia, and bilateral upper limb dysmetria was found to have a cerebellar mass on magnetic resonance imaging (MRI). He was initially treated with corticosteroids as a case of neurosarcoidosis. The patient's symptoms worsened, and repeat MRI showed an increase in the tumor size with hydrocephalus. External ventricular drain insertion plus midline suboccipital craniotomy and resection of the tumor was performed. Pathology revealed MB classic type, sonic hedgehog-activated. There was no cerebrospinal fluid dissemination. He received craniospinal radiation and chemotherapy. Follow-up 20 months after radiation revealed residual neurologic symptoms and no recurrence on MRI brain.

CONCLUSIONS

The exceedingly rare coexistence of adult MB and sarcoidosis may have a causal relationship based on specific common molecules. Leukotrienes, stimulation of astrocytes and Purkinje neurons, and the sonic hedgehog signaling pathway can be considered. Further genetic and molecular studies are merited.

Detrimental Influence of Alveolar Macrophages on Protective Humoral Immunity during Francisella tularensis SchuS4 Pulmonary Infection

Opsonizing antibody is a critical component of the host protective immune response against many respiratory pathogens. However, the role of antibodies in protection against pulmonary infection with highly virulent Francisella tularensis strain SchuS4 is unclear, and the mechanism that allows F. tularensis to evade antibody-mediated bacterial clearance is not fully understood. We have now found that depletion of alveolar macrophages reveals an otherwise cryptic protective effect of opsonizing antibody. While antibody opsonization alone failed to confer any survival benefit against SchuS4 lung infection, significant protection was observed when mice were depleted of alveolar macrophages prior to infection. Blood immune signature analyses and bacterial burden measurements indicated that the treatment regimen blocked establishment of productive, systemic infection. In addition, protection was found to be dependent upon neutrophils. The results show for the first time a protective effect of opsonizing antibodies against highly virulent F. tularensis SchuS4 pulmonary infection through depletion of alveolar macrophages, the primary bacterial reservoir, and prevention of systemic dissemination. These findings have important implications for the potential use of therapeutic antibodies against intracellular pathogens that may escape clearance by residing within mucosal macrophages.

Determining the presence of asthma-related molecules and salivary contamination in exhaled breath condensate

Background

Researchers investigating lung diseases, such as asthma, have questioned whether certain compounds previously reported in exhaled breath condensate (EBC) originate from saliva contamination. Moreover, despite its increasing use in ‘omics profiling studies, the constituents of EBC remain largely uncharacterized. The present study aims to define the usefulness of EBC in investigating lung disease by comparing EBC, saliva, and saliva-contaminated EBC using targeted and untargeted mass spectrometry and the potential of metabolite loss from adsorption to EBC sample collection tubes.

Methods

Liquid chromatography mass spectrometry (LC-MS) was used to analyze samples from 133 individuals from three different cohorts. Levels of amino acids and eicosanoids, two classes of molecules previously reported in EBC and saliva, were measured using targeted LC-MS. Cohort 1 was used to examine contamination of EBC by saliva. Samples from Cohort 1 consisted of clean EBC, saliva-contaminated EBC, and clean saliva from 13 healthy volunteers; samples were analyzed using untargeted LC-MS. Cohort 2 was used to compare eicosanoid levels from matched EBC and saliva collected from 107 asthmatic subjects. Samples were analyzed using both targeted and untargeted LC-MS. Cohort 3 samples consisted of clean-EBC collected from 13 subjects, including smokers and non-smokers, and were used to independently confirm findings; samples were analyzed using targeted LC-MS, untargeted LC-MS, and proteomics. In addition to human samples, an in-house developed nebulizing system was used to determine the potential for EBC samples to be contaminated by saliva.

Results

Out of the 400 metabolites detected in both EBC and saliva, 77 were specific to EBC; however, EBC samples were concentrated 20-fold to achieve this level of sensitivity. Amino acid concentrations ranged from 196 pg/mL – 4 μg/mL (clean EBC), 1.98 ng/mL – 6 μg/mL (saliva-contaminated EBC), and 13.84 ng/mL – 1256 mg/mL (saliva). Eicosanoid concentration ranges were an order of magnitude lower; 10 pg/mL – 76.5 ng/mL (clean EBC), 10 pg/mL – 898 ng/mL (saliva-contaminated EBC), and 2.54 ng/mL – 272.9 mg/mL (saliva). Although the sample size of the replication cohort (Cohort 3) did not allow for statistical comparisons, two proteins and 19 eicosanoids were detected in smoker vs. non-smoker clean-EBC.

Conclusions

We conclude that metabolites are present and detectable in EBC using LC-MS; however, a large starting volume of sample is required.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-017-0538-5) contains supplementary material, which is available to authorized users.

Eicosanoids in exhaled breath condensate and BAL fluid of patients with sarcoidosis

BACKGROUND

Measurement of inflammatory mediators in exhaled breath condensate (EBC) is an easy and noninvasive diagnostic method, which has gained popularity in the past few years. However, the source of these mediators is not precisely defined. It has been only presumed that inflammatory cells present in the airway lumen are the main source. Therefore, the aim of this study was to verify the relationship between EBC and BAL fluid (BALF) eicosanoids, and the percentage, number, and activity of cells in BALF.

METHODS

In 28 sarcoidosis patients and 17 healthy subjects, 8-isoprostane, cysteinyl leukotrienes (CysLTs), and leukotriene B4 (LTB4) were measured in EBC by enzyme immunoassay. Eicosanoids were also examined in BALF in the study group. Cell count, percentage, and superoxide production by BALF cells were estimated.

RESULTS

The mean (+/- SEM) CysLT and 8-isoprostane concentrations were higher in the sarcoidosis group (6.5 +/- 0 vs 27.82 +/- 6.65 pg/mL, respectively; and 2.67 +/- 0.16 vs 13.95 +/- 2.59 pg/mL, respectively). There were positive correlations between EBC and BALF 8-isoprostane concentration (r = 0.68, p < 0.0001) and LTB4 concentration (r = 0.43; p = 0.026). EBC LTB4 levels correlated with the number of lymphocytes per milliliter of BALF. The percentage and number of eosinophils in BALF correlated with EBC 8-isoprostane and BALF CysLT concentrations. No positive correlation was found between concentrations of EBC eicosanoids and percentages BALF lymphocytes, BALF macrophages, or superoxide production.

CONCLUSIONS

The levels of 8-isoprostane and CysLT are elevated in EBC in sarcoidosis patients; however, a lack of correlation with BALF lymphocyte percentage does not encourage us to recommend the measurement of eicosanoids as activity markers. The positive correlation of EBC 8-isoprostane and BALF CysLT concentrations with the percentage of eosinophils in BALF, and the higher percentage of eosinophils in BALF from patients with grade 3 sarcoidosis, may suggest the possible prognostic value.

Cyclooxygenase-2 (COX-2) inhibition limits abnormal COX-2 expression and progressive injury in the remnant kidney

BACKGROUND

The pathogenesis of progressive nephropathies involves hemodynamic and inflammatory factors. In the 5/6 nephrectomy model, a selective increase of cyclooxygenase-2 (COX-2) expression was shown, whereas treatment with a nonsteroidal anti-inflammatory or a specific COX-2 inhibitor was renoprotective. We investigated in the 5/6 nephrectomy model (1) the renal distribution of COX-2; (2) the hemodynamic and cellular mechanisms by which chronic COX-2 inhibition prevents renal injury.

METHODS

After 5/6 nephrectomy, adult male Munich-Wistar rats were subdivided in two groups: 5/6 nephrectomy (N=20), receiving vehicle, and 5/6 nephrectomy + celecoxib (N=19), treated orally with the COX-2 inhibitor, celecoxib, 10 mg/kg/day. Untreated and treated (celecoxib) sham-operated rats were also studied. Renal hemodynamics were examined at 4 weeks, whereas renal morphologic/immunohistochemical studies were carried at 8 weeks.

RESULTS

At 4 weeks, 5/6 nephrectomy rats exhibited marked systemic and glomerular hypertension. Celecoxib attenuated both systemic and glomerular hypertension, without affecting glomerular filtration rate (GFR). At 8 weeks, glomerulosclerosis and interstitial expansion were evident in 5/6 nephrectomy rats, and markedly attenuated in 5/6 nephrectomy rats given celecoxib. In both sham-operated and 5/6 nephrectomy rats, COX-2 was expressed at the macula densa. The extent of COX-2 expression at the macula densa was nearly tripled by celecoxib, indicating the existence of a feedback mechanism. In 5/6 nephrectomy rats, COX-2 was also expressed in glomeruli, arterioles, and the cortical interstitium, mostly at inflamed or sclerosing areas. Celecoxib markedly attenuated renal injury, inflammation, and ectopic COX-2 expression in 5/6 nephrectomy rats.

CONCLUSION

Chronic COX-2 inhibition attenuated progressive nephropathy by reducing glomerular hypertension, renal inflammation, and ectopic COX-2 expression, indicating a complex contribution of COX-2 to progressive renal injury in 5/6 nephrectomy rats.

Sarcoidosis

Sarcoidosis is a systemic granulomatous disease of unknown cause that most commonly affects the lungs, lymph nodes, skin, eyes, spleen, bone, and glandular tissue. The diagnosis is made when characteristic histologic findings are demonstrated and other granulomatous processes are excluded. It can be an acute or chronic debilitating disease, but in patients with acute disease the process can be self-limited. Multiple therapeutic options have been described both for the cutaneous and systemic lesions of sarcoidosis. Steroids, however, remain the cornerstone of therapy.

Sarcoidosis

Sarcoidosis is a systemic noncaseating granulomatous disorder of unknown origin. The cutaneous manifestations of sarcoidosis often enable the dermatologist to be the first physician to make the diagnosis. This article reviews essential sarcoidosis pathophysiology, clinical polymorphisms, systemic evaluation, and treatment modalities for cutaneous sarcoidosis to further enhance the dermatologist's understanding of this disease entity.

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should be familiar with the theories of the pathogenesis of sarcoidosis, its cutaneous manifestations, its various syndromes and associations, and its presentation in children. Participants should also be more knowledgeable about diagnostic evaluation, measurement of disease progression, treatment modalities, and the prognosis and mortality data of sarcoidosis.

Evaluation of the measurement of leukotriene B4 concentrations in exhaled condensate as a noninvasive method for assessing mediators of inflammation in the lungs of calves

OBJECTIVE

To determine whether measurement of an inflammatory mediator in exhaled condensate could provide a noninvasive method for evaluating lungs of calves.

ANIMALS

84 calves < or = 2 months old.

PROCEDURE

Concentration of leukotriene B4 (LTB4) was evaluated in the exhaled condensate of healthy calves and calves with experimentally induced respiratory tract infections. For collection of samples of exhaled condensate, the total amount of exhaled air was directed into a cooled double-jacketed tube. Each tube was sealed and stored at -80 C. The LTB4 concentration was measured, using an ELISA.

RESULTS

In exhaled condensates of clinically healthy calves, normally distributed and highly reproducible LTB4 concentrations (mean +/- SD, 116.1 +/- 55.4 pg/ml) were measured. After experimentally induced infection with Pasteurella multocida serovar D, LTB4 in exhaled condensate increased significantly (mean, 179% increase), compared with basal concentrations before infection; this increase in LTB4 was significantly correlated with deterioration in lung function. In 2 of 4 calves experimentally infected with bovine respiratory syncytial virus, the LTB4 concentration in exhaled condensate increased (300 to 400% increase), compared with baseline values, which was associated with development of bronchial hyperresponsiveness after infection.

CONCLUSIONS AND CLINICAL RELEVANCE

Collection of exhaled condensate is tolerated well by calves and is an acceptable method for obtaining fluid from exhaled air originating from the lungs. This method provides alternatives for diagnosing and evaluating treatment of naturally acquired and experimentally induced diseases of the lungs and airways in calves.