Distribution Of Inflammatory Cells Research Articles

Impact of 5-lipoxygenase inhibitors on the spatiotemporal distribution of inflammatory cells and neuronal COX-2 expression following experimental traumatic brain injury in rats

The inflammatory response following traumatic brain injury (TBI) contributes to neuronal death with poor outcome. Although anti-inflammatory strategies were beneficial in the experimental TBI, clinical translations mostly failed, probably caused by the complexity of involved cells and mediators. We recently showed in a rat model of controlled cortical impact (CCI) that leukotriene inhibitors (LIs) attenuate contusion growth and improve neuronal survival. This study focuses on spatiotemporal characteristics of macrophages and granulocytes, typically involved in inflammatory processes, and neuronal COX-2 expression. Effects of treatment with LIs (Boscari/MK-886), started prior trauma, were evaluated by quantifying CD68+, CD43+ and COX-2+ cells 24h and 72h post-CCI in the parietal cortex (PC), CA3 region, dentate gyrus (DG) and visual/auditory cortex (v/aC). Correlations were applied to identify intercellular relationships. At 24h, untreated animals showed granulocyte invasion in all regions, decreasing towards 72h. Macrophages increased from 24h to 72h post-CCI in PC and v/aC. COX-2+ neurones showed no temporal changes, except of an increase in the CA3 region at 72h. Treatment reduced granulocytes at 24h in the pericontusional zone and hippocampus, and macrophages at 72h in the PC and v/aC. COX-2 expression remained unaffected by LIs, except of time-specific changes in the DG (increase/decrease at 24/72h). Interrelations confirmed concomitant cellular reactions beyond the initial trauma site. In conclusion, LIs attenuated the cellular inflammatory response following CCI. Future studies have to clarify region-specific effects and explore the potential of a clinically more relevant therapeutic approach applying LIs after CCI.

Effect of albendazole therapy on susceptible and resistant Haemonchus contortus larvae in Mongolian gerbils (Meriones unguiculatus) and distribution of inflammatory cells in the stomach wall

Abstract The effect of albendazole therapy on the reduction of drugsusceptible and drug-resistant strains of Haemonchus contortus larvae on day 10 post infection (p.i.), distribution and the relative numbers of innate immunity cells — eosinophils/neutrophils and mast cells in the stomach wall of immunosupressed Mongolian gerbils on days 4/1, 7/4, 10/7 and 14/11 post infection/post therapy (p.i./p.t.) were investigated in the present study. The efficacy of albendazole was significantly lower on benzimidazole (BZ) resistant larvae (L3 and L4 stages) (58.92 %) than the efficacy on susceptible strain of larvae (94.15 %). H. contortus infection elicited strong inflammation in mucosal and submucosal layers of the stomach, where mucosal mast cells MMC) were in the highest numbers in the lamina propria mucosae on day 7/4 p.i./p.t. Reduction of larval numbers following treatment resulted in a gradual decrease of MMC and connective tissue mast cells (CTMC). The lower counts of CTMC in the submucosa were seen in gerbils infected with BZ-susceptible strain during the whole period post therapy. In case of infection with BZ-resistant strain, peroxidase containig cells (eosinophils) peaked on day 7/4 p.i./p.t., whereas infection with BZ-susceptible strain elicited massive accumulation of these cells on day 4/1 p.i./p.t., particularly in the submucosa. No marked differences in eosinophils localisation were observed between both groups after the therapy. Goblet cells were found only in the proximal parts of glandulae gastricae close to the mucosal surface and no differences in the distribution in the stomach wall of both groups of animals were observed. After therapy the higher larval counts in case of BZ-resistant strain were in the correlation with the lower decline of CTMC and eosinophils, but MMC numbers were not significantly different between both treated groups. Present data indicate that in early stage post infection, the distribution of individual innate immunity cells might be directly affected by the larvae, and that the genetic and consequently biological differences related to the resistance to benzimidazoles probably had the impact on the interactions of larvae with the different immune cells in their niche.

MMP9 regulates the cellular response to inflammation after skeletal injury

Like other tissue injuries, bone fracture triggers an inflammatory response, which plays an important role in skeletal repair. Inflammation is believed to have both positive and negative effects on bone repair, but the underlying cellular mechanisms are not well understood. To assess the role of inflammation on skeletal cell differentiation, we used mouse models of fracture repair that stimulate either intramembranous or endochondral ossification. In the first model, fractures are rigidly stabilized leading to direct bone formation, while in the second model, fracture instability causes cartilage and bone formation. We compared the inflammatory response in these two mechanical environments and found changes in the expression patterns of inflammatory genes and in the recruitment of inflammatory cells and osteoclasts. These results suggested that the inflammatory response could influence skeletal cell differentiation after fracture. We then exploited matrix metalloproteinase 9 (MMP9) that is expressed in inflammatory cells and osteoclasts, and which we previously showed is a potential regulator of cell fate decisions during fracture repair. Mmp9−/− mice heal stabilized fractures via endochondral ossification, while wild type mice heal via intramembranous ossification. In parallel, we observed increases in macrophages and T cells in the callus of Mmp9−/− compared to wild type mice. To assess the link between the profile of inflammatory cells and skeletal cell fate functionally, we transplanted Mmp9−/− mice with wild type bone marrow, to reconstitute a wild type hematopoietic lineage in interaction with the Mmp9−/− stroma and periosteum. Following transplantation, Mmp9−/− mice healed stabilized fractures via intramembranous ossification and exhibited a normal profile of inflammatory cells. Moreover, Mmp9−/− periosteal grafts healed via intramembranous ossification in wild type hosts, but healed via endochondral ossification in Mmp9−/− hosts. We observed that macrophages accumulated at the periosteal surface in Mmp9−/− mice, suggesting that cell differentiation in the periosteum is influenced by factors such as BMP2 that are produced locally by inflammatory cells. Taken together, these results show that MMP9 mediates indirect effects on skeletal cell differentiation by regulating the inflammatory response and the distribution of inflammatory cells, leading to the local regulation of periosteal cell differentiation.

Immunophenotypic Identification and Characterization of Tumor Cells and Infiltrating Cell Populations in Meningiomas

Meningiomas are primary tumors of the central nervous system composed of both neoplastic and other infiltrating cells. We determined the cellular composition of 51 meningioma samples by multiparameter flow cytometric (MFC) immunophenotyping and investigated the potential relationship between mRNA and protein expression levels of neoplastic cells. For immunophenotypic, morphologic, and cytogenetic characterization of individual cell populations, a large panel of markers was used together with phagocytic/endocytic functional assays and MFC sorting. Overall, our results revealed coexistence of CD45(-) neoplastic cells and CD45(+) immune infiltrating cells in all meningiomas. Infiltrating cells included tissue macrophages, with an HLA-DR(+)CD14(+)CD45(+)CD68(+)CD16(-/+)CD33(-/+) phenotype and high phagocytic/endocytic activity, and a small proportion of cytotoxic lymphocytes (mostly T CD8(+) and natural killer cells). Tumor cells expressed multiple cell adhesion proteins, tetraspanins, HLA-I/HLA-DR molecules, complement regulatory proteins, cell surface ectoenzymes, and growth factor receptors. Noteworthy, the relationship between mRNA and protein levels was variable, depending on the proteins evaluated and the level of infiltration by immune cells. In summary, our results indicate that MFC immunophenotyping provides a reliable tool for the characterization of the patterns of protein expression of different cell populations coexisting in meningioma samples, with a more accurate measure of gene expression profiles of tumor cells at the functional/protein level than conventional mRNA microarray, independently of the degree of infiltration of the tumor by immune cells.

Immune and Inflammatory Cell Involvement in the Pathology of Idiopathic Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is characterized by vasoconstriction and vascular remodeling. Recent studies have revealed that immune and inflammatory responses play a crucial role in pathogenesis of idiopathic PAH. To systematically evaluate the number and cross-sectional distribution of inflammatory cells in different sizes of pulmonary arteries from explanted lungs of patients with idiopathic PAH versus healthy donor lungs and to demonstrate functional relevance by blocking stromal-derived factor-1 by the Spiegelmer NOX-A12 in monocrotaline-induced pulmonary hypertension in rats. Immunohistochemistry was performed on lung tissue sections from patients with idiopathic PAH and healthy donors. All positively stained cells in whole-lung tissue sections, surrounding the vessels, and in the different compartments of the vessels were counted. To study the effects of blocking SDF-1, rats with monocrotaline-induced pulmonary hypertension were treated with NOX-A12 from Day 21 to Day 35 after monocrotaline administration. We found a significant increase of the perivascular number of macrophages (CD68(+)), macrophages/monocytes (CD14(+)), mast cells (toluidine blue(+)), dendritic cells (CD209(+)), T cells (CD3(+)), cytotoxic T cells (CD8(+)), and helper T cells (CD4(+)) in vessels of idiopathic PAH lungs compared with control subjects. FoxP3(+) mononuclear cells were significantly decreased. In the monocrotaline model, the NOX-A12-induced reduction of mast cells, CD68(+) macrophages, and CD3(+) T cells was associated with improvement of hemodynamics and pulmonary vascular remodeling. Our findings reveal altered perivascular inflammatory cell infiltration in pulmonary vascular lesions of patients with idiopathic pulmonary arterial hypertension. Targeting attraction of inflammatory cells by blocking stromal-derived factor-1 may be a novel approach for treatment of PAH.

Comparison of centrifuged liquid based cytology method with conventional brush cytology in oral lesions

Abstract Background: Exfoliative cytology is the study of cells that are shed or scrapped off from mucosal surfaces. Centrifuged Liquid based cytology is a modified technique employed in the present study. Aims: To compare the utility of centrifuged liquid based cytology with conventional cytology in oral lesions after staining with Papanicolaou (PAP) stain. Materials and Methods: 50 cases of oral lesions comprising of normal mucosa (n=14), hyperkeratotic lesions (n=17), ulcerated lesions (n=7) and atrophic lesions (n=12) were selected. Two smears were obtained from the lesion using a cytological brush. One was spread on the slide using conventional technique, fixed immediately in 95% ethyl alcohol. Second sample was suspended in suspending solution for 10 minutes then spun in centrifuge for 10 minutes. The supernatant was poured off and the obtained cell pellet was used to prepare a smear by sedimentation and left to dry overnight. Both the smears were stained by PAP. The stained smears were compared for seven morphological parameters such as adequacy of smear, clear background, cell distribution, smear thickness, cell morphology, and presence of blood, inflammatory cells, microbial colonies and artifacts. Wilcoxon Signed rank test was used and P≤0.05 was considered statistically significant. Results: There was a statistically significant difference (P<0.001) between centrifuged liquid based cytology and conventional cytology when clear background was evaluated while in all other parameters the difference was not significant. Conclusion: Centrifuged Liquid based cytology showed clearer background than conventional brush cytology in oral lesions.

Osteoarthritis progression is accompanied by inflammatory CD4+ T-cell polarisation

Purpose: While OA has generally been considered a “non-inflammatory” disease, there is an increasing body of evidence about the presence of inflammatory cells and cytokines in OA synovium suggesting they play a role in disease progression. It is still controversial which cell types in OA synovium are responsible for maintaining synovial inflammation, and more importantly how the distribution of inflammatory cells, their activation status and polarisation changes with OA progression. The overarching aim of this project was to quantitatively analyse the presence of inflammatory cells and their main pro-inflammatory cytokines in the affected joints of patients with different OA stages. We aimed to investigate T-cell polarisation and activation with OA disease progression. Methods: Synovial membrane (SM), Synovial fluid (SF) and peripheral blood (PB) were harvested from a total of 120 patients (75 women, 45 men, mean age of 67.8 ± 8 years) with different OA stages (Kellgren-Lawrence I-IV). Patients were scheduled for arthroscopy (group 1, K&L I), partial knee replacement (group 2, K&L II-III) and total knee replacement (group 3, K&L IV) in our clinic. PB samples from healthy controls were included. After enzymatic digestion (SM) and gradient centrifugation (SM, PB), mononuclear cells were isolated and analysed by FACS for cell surface and intracellular markers specific for mononuclear cells, T cell subsets (Th1, Th2, Th17, Treg) and activation markers. T-cell cytokine secretion (IL-2, IL-4, IL-6, IL-10, IL-17A, INF-γ, TNF) in SF was measured by cytometric bead array (CBA) analysis. Results: Analysis of PB did not show any significant difference within the OA patient groups and in comparison to controls. In SM a distinct infiltration of CD4+ T-cells was present in all three OA groups, which significantly increased with OA stage (p<0.05). Further, CD4+ T-cell subsets in SM and PB samples were analysed. Whereas in PB only a small proportion of CD4+ T-cells were activated and stained positive for the specific subsets, the majority of SM T-cells were differentiated into the T-cell subsets and this increased with OA stage (Figure 1). The highest increase was measured for the inflammatory T cell subsets Th1 and Th17, which significantly altered the Th1/Th2 and Th17/Treg balance. Further analysis of activation markers displayed an activated phenotype of CD4+ T-cells in the SM (CD69+, CD45RO+, CD45RA-, CD62L-) but not in PB. CBA analysis confirmed a significant increase of all T-cell cytokines in the SF of OA groups 2 and 3 when compared to group 1 (p<0.05). Between group 2 and 3, pro-inflammatory Th1 and Th17 cytokines (TNF and IL-17) were further increased and anti-inflammatory Th2 and Treg cytokines (IL-4, IL-10) decreased in group 3. IL-2, IL-6 and INF-γ were slightly higher in group 2. Conclusions: In contrast to SM, no differences were observed between the PB samples of OA patients and controls, showing that the relevant role of inflammatory cells in OA remains a local process. The infiltration of OA synovium with inflammatory cells is not solely a phenomenon of late stage OA. In fact, CD4+ T-cells are already present and activated in the affected joints of early OA stages. T-cell infiltration and polarisation correlates with OA disease stages and shifts the Th1/Th2 and Th17/Treg balance towards an inflammatory T-cell phenotype. Thus, onset and progression of OA is accompanied by an increasing influx of CD4+ T-cells into the SM, their activation, cytokine production and polarisation. These results underline the relevance of T-cells in the inflammatory process of OA, not only in late-stage disease but also in early OA stages. In “classical” inflammatory joint diseases such as rheumatoid arthritis we know that T-cell derived inflammation contributes to cartilage degeneration and joint destruction. The role of these cells in OA needs to be further studied. Nevertheless our current results suggest that T-cell activation and polarisation may play a role in both the initiation and progression of OA, and as such provide a potential therapeutic target.

An Activated Immune and Inflammatory Response Targets the Pancreas of Newborn Pigs with Cystic Fibrosis

Background/Aims: In cystic fibrosis (CF), pancreatic disease begins in utero and progresses over time to complete destruction of the organ. Although inflammatory cells have been detected in the pancreas of humans and pigs with CF, their subtypes have not been characterized. Methods: Using four-color flow cytometry, we analyzed the surface antigens of leukocytes in pancreas, blood, and mesenteric lymph nodes (MLN) of newborn pigs with CF (CFTR-/- and CFTRΔF508/ΔF508) and in those without CF (CFTR+/-, CFTR13+/ΔF508, CFTR+/+). Pancreatic histopathology was examined with HE stain. Results: CF pig pancreas had patchy distribution of inflammatory cells with neutrophils/macrophages in dilated acini, and lymphocytes in the interstitium compared to non-CF. B cells, effector (MHC-II+) and cytotoxic (CD2+CD8+) γδ T cells, activated (MHC-II+ and/or CD25+) and effector (CD4+CD8+) αβ T helper cells, effector natural killer cells (MHC-II+CD3-CD8+), and monocytes/macrophages and neutrophils were increased in the CF pig pancreas compared to pigs without CF. Blood and MLN leukocyte populations were not different between CF and non-CF pigs. Conclusions: We discovered an activated immune response that was specific to the pancreas of newborn CF pigs; inflammation was not systemic. The presence of both innate and adaptive immune cells suggests that the disease process is complex and extensive.

Distribution of Inflammatory Cells, Adhesion Molecules, Intermediate Filaments, and Chemokine Receptors in Subgroups of Nasal Polyp Patients

The pathogenesis of nasal polyps (NPs) is incompletely understood. The aim of this study was to investigate the distribution of inflammatory cells, adhesion molecules, intermediate filaments, and chemokine receptors in subgroups of NP patients. In total, 35 patients were enrolled (group 1, 10 patients with Samter syndrome; group 2, 10 patients with diffuse polyposis without signs of Samter syndrome; group 3: 5 patients with solitary nasal polyps; group 4, 10 controls). Immunohistochemical staining was performed for CD105, CD106, CD62E, CD4, CD8, CXCR4, CD147, CD90, CD104, BF45, vimentin, pancytokeratin, and muscle-specific actin (MSA) in all patients' specimens. Expression of CD4, CD8, and CD106 were similar between the groups. Number of patients expressing CD4 in groups 1, 2, and 3 were higher than the controls. Number of patients expressing CD8 antigen were significantly higher in all three groups than in the control group. Expression of CD147 in groups 3 and 4 was significantly higher than in groups 1 and 2. CD98 expression was higher in groups 1, 2, and 3 than in group 4. The number of patients expressing vimentin in groups 1, 2, and 3 was significantly higher than in group 4. Immunostaining for pancytokeratin was positive in all patients. In conclusion, inflammatory cell, adhesion molecule, intermediate filament, and chemokine receptor profiles in nasal polyps differ among different patient groups and control subjects. Additional specific immunohistochemical studies are necessary for development of more specific immunotherapies.

Subclinical responses in healthy cyclists briefly exposed to traffic-related air pollution: an intervention study

BackgroundNumerous epidemiological studies have demonstrated adverse health effects of a sedentary life style, on the one hand, and of acute and chronic exposure to traffic-related air pollution, on the other. Because physical exercise augments the amount of inhaled pollutants, it is not clear whether cycling to work in a polluted urban environment should be encouraged or not. To address this conundrum we investigated if a bicycle journey along a busy commuting road would induce changes in biomarkers of pulmonary and systematic inflammation in a group of healthy subjects.Methods38 volunteers (mean age: 43 ± 8.6 years, 26% women) cycled for about 20 minutes in real traffic near a major bypass road (road test; mean UFP exposure: 28,867 particles per cm3) in Antwerp and in a laboratory with filtered air (clean room; mean UFP exposure: 496 particles per cm3). The exercise intensity (heart rate) and duration of cycling were similar for each volunteer in both experiments. Exhaled nitric oxide (NO), plasma interleukin-6 (IL-6), platelet function, Clara cell protein in serum and blood cell counts were measured before and 30 minutes after exercise.ResultsPercentage of blood neutrophils increased significantly more (p = 0.004) after exercise in the road test (3.9%; 95% CI: 1.5 to 6.2%; p = 0.003) than after exercise in the clean room (0.2%; 95% CI: -1.8 to 2.2%, p = 0.83). The pre/post-cycling changes in exhaled NO, plasma IL-6, platelet function, serum levels of Clara cell protein and number of total blood leukocytes did not differ significantly between the two scenarios.ConclusionsTraffic-related exposure to particles during exercise caused a small increase in the distribution of inflammatory blood cells in healthy subjects. The health significance of this isolated change is unclear.

Quantitative measurement of mature collagen cross-links in human carotid artery plaques

While there is an appreciable understanding of the importance of collagen breakdown in contributing to atherosclerotic plaque vulnerability and rupture, little is known about changes in collagen maturation in the atherosclerotic plaque. This is achieved through the formation of the covalent intermolecular cross-links pyridinoline (Pyd) and deoxypyridinoline (Dpd). In this study we collected carotid endarterectomy specimens from patients and undertook (i) histological assessment of collagen and inflammatory cell distribution and (ii) biochemical analysis of total collagen and cross-link content. Greater collagen deposition, increased presence of CD68 positive cells and an increased Pyd:Dpd ratio (an indicator of lysyl hydroxylase (LH-1) activity) were found in plaque versus normal vascular tissue. These findings are the first measurements of Pyd and Dpd cross-links in normal and atherosclerotic vascular tissue. The observed differences in cross-links in the plaque may adversely affect tensile strength and may have relevance to the mechanisms underlying rupture of vulnerable plaques.

Quantitative Short-Tandem Repeat Analysis of Recipient-Derived Cells as an Additional Tool for Diagnosing Cardiac Allograft Rejection

Diagnosis of cardiac allograft rejection is currently based on histologic exploration of endomyocardial biopsies. Moderate interobserver reproducibility in the estimation of number and distribution of inflammatory cells leads to disagreements in the assignment of rejection grades. Short-tandem repeat (STR) analysis is routinely used after hematopoietic stem-cell transplantation to determine the proportions of donor cells. We compared the amount of recipient-derived cells with the histopathologic grade of rejection in cardiac allografts to determine whether this method might be useful for the assessment of rejection episodes. One hundred forty-three endomyocardial biopsies from 18 patients were investigated for the percentage of recipient-derived cell content by polymerase chain reaction-based STR analysis and correlated with rejection grades determined according to the International Society for Heart and Lung Transplantation grading system. Y-chromosome chromogene in situ hybridization was performed in gender-mismatched (female-to-male) heart transplants to explore the influence of cardiomyocyte cell chimerism. The mean percentages of recipient-derived cells associated with various degrees of rejection were 13% in grade 0, 24% in grade 1A, 29% in grade 1B, 35% in grade 2, and 50% in grade > or =3A. Samples lacking signs of rejection (grade 0) had a significantly lower (P<0.001) amount of recipient-derived cells than higher degrees of rejections. Chromogene in situ hybridization analysis revealed that the recipient-derived cells were mainly inflammatory. The results of STR-analysis indicate that rejection is correlated with a higher proportion of recipient-derived cells. This assessment is observer independent and may thus represent an additional diagnostic tool for the assessment of rejection and management of immunosuppressive treatment.

Airway and alveolar inflammation assessments with bronchoalveolar lavage in various interstitial lung disorders

Fractional analysis of bronchoalveolar lavage (FABAL) fluid was performed in 6 control patients and 41 patients with various interstitial lung disease. The cell differential counts in the first 30 ml fraction of BAL (FBAL-I), which is considered to be the bronchial lavage, differed from those of the 50 ml second and third fraction (FBAL-III). Hypersensitivity pneumonitis, pulmonary tuberculosis, and sarcoidosis showed a high recovery of lymphocytes (52%); however, the former two disorders were occasionally, associated with neutrophil airway inflammation, whereas sarcoidosis was not. The percentage recovery of neutrophils in total FBAL was considerably high in patients with diffuse panbronchiolitis, and relatively high in those with collagen vascular disease, idiopathic pulmonary fibrosis, pneumoconiosis, and control smokers. However, these neutrophils were largely recovered from FBAL-I, suggesting the presence of airway inflammation. Thus, it is valuable to apply the FBAL method to determine the topographic distribution of inflammatory cells in the lungs. It was also found that the lymphocyte morphology in the lavage fluid was of value in establishing the diagnosis of hypersensitivity pneumonitis, and it is critical whether or not mast cells and basophils are present in BALF since they indicate the pathologic state of allergy or fibrosis. Although present in various fibrotic lung diseases in a limit number, langerhans cells are a diagnostic marker for histiocytosis X.

Multiple sclerosis: Distribution of inflammatory cells in newly forming lesions

CD4 T-cell-dependent macrophage activation directed against a myelin or oligodendrocyte antigen is generally thought to be the mechanism causing myelin destruction in multiple sclerosis (MS). However, areas within expanding MS lesions may exhibit prominent oligodendrocyte loss and apoptosis in the absence of infiltrating lymphocytes. The present study was designed to further investigate the inflammatory profile of different regions within rapidly expanding MS lesions. Twenty-six active lesions from 11 patients with early MS were serially sectioned and immunostained for T and B cells, plasma cells, ramified microglia, macrophages, monocytes, and CD209-positive dendritic cells. Cell counts were compared in prephagocytic, phagocytic, and immediately postphagocytic areas. Parenchymal T and B cells were largely absent in areas of initial oligodendrocyte loss and in areas of degenerate and dead myelin infiltrated by myelin phagocytes. In contrast, trailing areas of complete demyelination packed with lipid macrophages, and, in some lesions, regenerating oligodendrocytes, showed large numbers of T cells, B cells, and immunoglobulin G (IgG)-positive plasma cells. Lesions in 2 exceptionally early cases contained relatively few T and B cells, and no IgG-positive plasma cells. Early loss of oligodendrocytes is a prominent feature in tissue bordering rapidly expanding MS lesions. Macrophage activity is largely an innate scavenging response to the presence of degenerate and dead myelin. Adaptive immune activity involving T and B cells is conspicuous chiefly in recently demyelinated tissue, which may show signs of oligodendrocyte regeneration. The findings suggest that plaque formation has some basis other than destructive cell-mediated immunity directed against a myelin or oligodendrocyte antigen.

Anatomy, pathology, and physiology of the tracheobronchial tree: Emphasis on the distal airways

This article covers the airway tree with respect to anatomy, pathology, and physiology. The anatomic portion discusses various primate groups so as to help investigators understand similarities and differences between animal models. An emphasis is on distal airway findings. The pathology section focuses on the inflammatory responses that occur in proximal and distal airways. The physiologic review brings together the anatomic and pathologic components to the functional state and proposes ways to evaluate the small airways in patients with asthma.

Increased Hepatic Myeloperoxidase Activity in Obese Subjects with Nonalcoholic Steatohepatitis

Inflammation and oxidative stress are considered critical factors in the progression of nonalcoholic fatty liver disease. Myeloperoxidase (MPO) is an important neutrophil enzyme that can generate aggressive oxidants; therefore, we studied the association between MPO and nonalcoholic fatty liver disease. The distribution of inflammatory cells containing MPO in liver biopsies of 40 severely obese subjects with either nonalcoholic steatohepatitis (NASH) (n = 22) or simple steatosis (n = 18) was investigated by immunohistochemistry. MPO-derived oxidative protein modifications were identified by immunohistochemistry and correlated to hepatic gene expression of CXC chemokines and M1/M2 macrophage markers as determined by quantitative PCR. MPO plasma levels were determined by ELISA. The number of hepatic neutrophils and MPO-positive Kupffer cells was increased in NASH and was accompanied by accumulation of hypochlorite-modified and nitrated proteins, which can be generated by the MPO-H2O2 system. Liver CXC chemokine expression was higher in patients with accumulation of MPO-mediated oxidation products and correlated with hepatic neutrophil sequestration. Plasma MPO levels were elevated in NASH patients. Interestingly, neutrophils frequently surrounded steatotic hepatocytes, resembling the crown-like structures found in obese adipose tissue. Furthermore, hepatic M2 macrophage marker gene expression was increased in NASH. Our data indicate that accumulation of MPO-mediated oxidation products, partly derived from Kupffer cell MPO, is associated with induction of CXC chemokines and hepatic neutrophil infiltration and may contribute to the development of NASH.

Changes in Corneal Epithelial Layer Inflammatory Cells in Aqueous Tear–Deficient Dry Eye

To investigate the morphology, distribution, and density of inflammatory cells in the corneal epithelium of aqueous tear-deficient dry eye. Thirty-two patients with non-Sjögren's syndrome (NSS) dry eye, 14 patients with Sjögren's syndrome (SS) dry eye, and 33 healthy volunteers were studied. In vivo laser scanning confocal microscopy was used to investigate both Langerhans cell (LCs) and leukocyte distribution and density in the peripheral and central corneal epithelium. LC morphology was also evaluated. Multifactor regression analysis assessed whether there is a correlation between clinical manifestations and inflammatory cell densities. LCs were present in both central (34.9 +/- 5.7 cells/mm(2)) and peripheral (90.7 +/- 8.2 cells/mm(2)) parts of the normal corneal epithelium. Moreover, LC density increased dramatically in the central corneal epithelium in patients with NSS (89.8 +/- 10.8 cells/mm(2)) and SS (127.9 +/- 23.7 cells/mm(2)). The ratio of LCs with obvious processes was much higher in patients with dry eye than in healthy volunteers. LC density also increased in peripheral corneal epithelium in patients with SS, but not in those with NSS. Leukocyte density in normal corneal epithelium was very low, whereas it increased in the central corneal epithelium (4.6 +/- 1.0 cells/mm(2)) in NSS and in both central (49.0 +/- 12.9 cells/mm(2)) and peripheral (84.2 +/- 36.8 cells/mm(2)) corneal epithelium in SS. Densities of LCs and leukocytes showed significant correlation with the severity found in clinical evaluation. The LC and leukocyte changes in the corneal epithelium suggest their involvement in aqueous tear-deficient dry eye pathophysiology. In vivo dynamic assessment of central corneal inflammatory cell density may serve as an indicator of dry eye severity and provide new insight for dry eye treatment.

Indistinguishable cellular changes in gastric mucosa between Helicobacter pylori infected asymptomatic tribal and duodenal ulcer patients.

To investigate the changing pattern of different histological parameters occurring in the stomach tissue of Helicobacter pylori (H pylori) infected tribal populations and duodenal ulcer patients among ethnic Bengalis and correlation of the genotypes of H pylori with different histological parameters. One hundred and twelve adult individuals were enrolled into this study between 2002 and 2004. Among them, 72 had clinical features of duodenal ulcer (DU) from ethnic Bengali population and 40 were asymptomatic ethnic tribals. Endoscopic gastric biopsy samples were processed for histology, genotyping and rapid urease test. Histologically, haematoxylin and eosin staining was applied to assess the pathomorphological changes and a modified Giemsa staining was used for better detection of H pylori. For intestinal metaplasia, special stainings, i.e. Alcian blue periodic acid-Schiff and high iron diamine-Alcian blue staining, were performed. PCR was performed on bacterial DNA to characterize the presence or absence of virulence-associated genes, like cagA, and distribution of different alleles of vacA and iceA. Intraglandular neutrophil infiltration, a hallmark of activity of gastritis, was present in 34 (94%) of tribals (TRs) and 42 (84%) of DU individuals infected with H pylori. Lymphoid follicles and aggregates, which are important landmarks in H pylori infection, were positive amongst 15 (41%) of TRs and 20 (40%) of DU subjects. Atrophic changes were observed in 60% and 27.7%, respectively, among DU cases and tribals (P > 0.003). Metaplastic changes were detected in low numbers in both groups. Moderate to severe density distribution of H pylori in the gastric mucosa was 63% among TRs, whereas it was 62% in DU subjects. There were no significant differences in the distribution of virulence-associated genes like cagA, vacA and iceA of H pylori strains carried by these two populations. Our study showed almost similar distribution of inflammatory cells among asymptomatic tribals and DU Bengali patients. Interestingly, the tribal population are free from any clinical symptoms despite evidence of active histologic gastritis and infection with H pylori strains carrying similar virulence markers as of strains isolated from patients with DU. There was an increased cellular response, especially in terms of neutrophil infiltration, but much lower risk of developing atrophy and metaplastic changes among the tribal population.

Disturbed Patterns of Immunocompetent Cells in Usual-Type Vulvar Intraepithelial Neoplasia

Genital infection with human papillomavirus (HPV) is usually transient, as the immune system is capable of eliminating the virus. When immunity "fails" and the infection persists, vulvar intraepithelial neoplasia (VIN) may develop. In this study, we examined the distribution of inflammatory cells in 51 patients with HPV-associated usual-type VIN and in 19 healthy controls. Frozen vulvar tissue samples were tested for the presence of HPV-DNA, and immunohistochemical staining for the markers CD1a, CD207, CD208, CD123/CD11c, CD94, CD4, CD8, and CD25/HLA-DR was performed. Cells were counted in both the epidermis and dermis over at least 2 mm of basal membrane length. In the epidermis of VIN patients, CD1a(+) and CD207(+) (Langerin) dendritic cells (DC) and CD8(+) T cells were significantly lower than in controls, whereas the number of CD123(+)/CD11c(-) plasmacytoid DCs (pDC) was significantly increased. No significant changes were observed for CD208(+) DCs, CD94(+) natural killer (NK) cells, CD4(+) T cells, and CD25(+)/HLA-DR(+) regulatory T cells. In the dermis of VIN patients, elevated numbers of CD208(+), CD123(+)/CD11c(-), CD94(+), CD4(+), CD8(+), and CD25(+)/HLA-DR(+) cells were observed when compared with healthy controls. The numbers of CD1a(+) and CD207(+) DCs were not different between groups. In summary, high-risk HPV-related usual-type VIN lesions are characterized by an immunosuppressive state in the epidermis, showing a reduction of immature myeloid DCs (mDC) and CD8(+) T cells. In the dermis, inflammatory activation is reflected by the influx of mature mDCs and pDCs, NK cells, and T cells, suggesting that the cellular immune response on viral HPV infection occurs in the dermis of VIN patients.

Induced sputum and bronchial mucosal expression of interleukin‐13 is not increased in chronic obstructive pulmonary disease

The Th2 cytokine interleukin-13 (IL-13) has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). We sought to examine IL-13 expression in COPD subjects in induced sputum and bronchus specimens. We hypothesized that inflammatory cells expressing IL-13 localize to the airway smooth muscle bundle and bronchial glands. Interleukin-13 was measured in sputum samples from subjects with COPD (n = 34) across a range of severity (Global initiative for chronic Obstructive Lung Disease 2-4) and controls (n = 14) using ELISA. IL-13+ cells and inflammatory cells were enumerated within surgically resected proximal airway using immunohistochemical techniques from subjects with COPD (n = 10), smoking (n = 10) and nonsmoking controls (n = 8). Sputum IL-13 was measurable in only 6/34 subjects with COPD and was not found in the smoking or nonsmoking control subjects. In subjects with COPD and controls there was a paucity of IL-13+ cells. The distribution of inflammatory cells within different airway compartments was similar in COPD and controls except for an increase in CD3(+) lymphocytes within bronchial glands in COPD (P = 0.04). Our findings do not support a role for IL-13 in COPD. However, the tissue localization of inflammatory cells to airway compartments, particularly the increase of T cells in glands in COPD may be important in disease.