Cytokine-induced sequential migration of neutrophils through endothelium and epithelium

RATIONALE AND OBJECTIVES: To evaluate different vein graft-coated stent systems in the endovascular treatment of experimental arteriovenous fistulae (AVF) in a canine model. METHODS: Bilateral carotid-to-external jugular vein AVF were created. Two balloon-expandable tantalum stents (Strecker stent), two self-expanding nitinol stents (Strecker stent), and one stainless-steel stent (Wallstent) were coated with autologous vein grafts and placed using a transfemoral approach. Angiography was performed immediately after stent placement and at week 1 and 3, as well as at months 3, 6, and 9. All stents were removed and underwent histologic examination. RESULTS: Occlusion of the AVF succeeded with the Wallstent and both tantalum stents. The nitinol stents were misplaced, maintaining the AVF. One undersized tantalum stent and the Wallstent were occluded after 3 weeks. One nitinol stent was occluded at 3 months, whereas the two remaining stents were patent during the whole observation period. No inflammatory tissue response was seen, and no host-versus-graft reaction was present. CONCLUSIONS: Preparation and implantation of vein graft-coated stents, especially in the case of self-expanding stent systems, is cumbersome. This restricts the common use of such a coating, which shows an excellent biocompatibility. Vein graft-coated stents might be of use in infected endangered vessels.     

Induction of fibrinogen expression in the lung epithelium during Pneumocystis carinii pneumonia

Pneumocystis carinii is an important pulmonary pathogen responsible for morbidity and mortality in patients with AIDS. The acute-phase response (APR), the primary mechanism used by the body to restore homeostasis following infection, is characterized by increased levels of circulating fibrinogen (FBG). Although the liver is the primary site of increased FBG synthesis during the APR, we unexpectedly discovered that FBG is synthesized and secreted by lung alveolar epithelial cells in vitro during an inflammatory stimulus. Therefore, we sought to determine whether lung epithelial cells produce FBG in vivo using animal models of P. carinii pneumonia (PCP). Inflammation was noted by an influx of macrophages to P. carinii-infected alveoli. Northern hybridization revealed that gamma-FBG mRNA increased two- to fivefold in P. carinii-infected lung tissue, while RNA in situ hybridization demonstrated increased levels of gamma-FBG mRNA in the lung epithelium. Immunoelectron microscopy detected lung epithelial cell-specific production of FBG, suggesting induction of a localized inflammatory response resembling the APR. A systemic APR was confirmed by a two- to fivefold upregulation of the levels of hepatic gamma-FBG mRNA in animals with PCP, resulting in a corresponding increase in levels of FBG in plasma. Furthermore, immunoelectron microscopy revealed the presence of FBG at the junction of cell membranes of trophic forms of P. carinii organisms aggregated along the alveolar epithelium. These results implicate FBG in the pathogenesis of PCP in a manner similar to that of the adhesive glycoproteins fibronectin and vitronectin, which are known to participate in intra-alveolar aggregation of organisms and adherence of P. carinii to the lung epithelium.     

Intercalated (basal) epitheliocytes and the regeneration of cholangiocytic epithelium in the liver

To clarify the function of human atrial natriuretic peptide (hANP) in the cerebrospinal fluid (CSF), we examined hANP levels in the CSF of patients with various neurological diseases. The subjects were 16 controls without neurological disease and 45 patients with neurological disease. The 45 patients with neurological disease were divided into a group of 15 patients with intracranial hypertension (IH) and a group of 30 patients with normal pressure (NP). hANP in both CSF (1-hANP) and serum (s-hANP) was measured by RIA. Patients with IH were followed up. We analyzed correlations between 1-hANP and other parameters of CSF. Increase in concentration of 1-hANP was positively correlated with intracranial pressure (ICP; r = 0.72; p < 0.01), but not with other CSF parameters or with s-hANP. The concentration of 1-hANP appeared to be increased especially over a threshold value of ICP. In a followup study of patients with IH, changes in 1-hANP paralleled changes in ICP in every case (r = 0.79; p < 0.01). Our findings strongly suggest that 1-hANP plays an important role in the regulation of ICP in humans.     

Paracrine endothelin signaling in the control of basal cell proliferation in guinea pig tracheal epithelium

Immunofluorescent analyses revealed distinct cellular/subcellular localization of endothelin (ET) receptors and ET-1 in the epithelial cell layer of guinea pig trachea. ETA was expressed predominantly in the basal cells. ETB was expressed predominantly in the ciliated columnar cells and was polarized at the apical side of the cell body within the cells. Anti-ET-1-immunoreactive cytoplasmic granules were contained in the secretory cells that were scattered throughout the epithelial layer. Cell proliferation assays with immersion cultures of differentially plated cells (basal cell-enriched, non-basal cell-enriched and mixed cell cultures) indicated the presence of paracrine ET-1 signaling pathways that transmit both positive and negative effects on the basal cell proliferation. Direct activation of ETA expressed on the basal cells caused enhancement of their growth, whereas that of ETB expressed on the ciliated columnar cells caused suppression of the basal cell growth. The latter effect was transmitted by nitric oxide whose production was stimulated by ETB activation. Furthermore, blockade of either ETA or ETB compromised the epithelial cell layer formation under the air-interphase culture, which indicates the dependence of tracheal epithelial remodeling on a balance between the positive and negative effects of ET-1 on the basal cell growth.     

Role of alveolar macrophages in initiation and regulation of inflammation in Pseudomonas aeruginosa pneumonia

To evaluate the role of alveolar macrophages (AMs) in acute Pseudomonas aeruginosa pneumonia in mice, AMs were depleted by aerosol inhalation of liposomes containing clodronate disodium. AM-depleted mice were then intratracheally infected with 5 x 10(5) CFU of P. aeruginosa. In addition to monitoring neutrophil recruitment and chemokine releases, lung injury was evaluated soon after infection (8 h) and at a later time (48 h). At 8 h, depletion of AMs reduced neutrophil recruitment, chemokine release, and lung injury. At 48 h, however, depletion of AMs decreased bacterial clearance and resulted in delayed movement of neutrophils from the site of inflammation with aggravated lung injury. With instillation of 5 x 10(7) CFU of bacteria, AM-depleted mice showed low mortality within 24 h of infection but high mortality at a later time, in contrast to non-AM-depleted mice. These results demonstrate that depletion of AMs has beneficial early effects but deleterious late effects on lung injury and survival in cases of P. aeruginosa pneumonia.     

Cyclophosphamide-induced generation of reactive oxygen species. Comparison with morphological changes in type II alveolar epithelial cells and lung capillaries

Immunosenescence involves modifications of humoral and cellular immunity. Here we report the analysis of human leukocyte antigen (HLA) expression on T lymphocytes, B lymphocytes and monocytes of 58 healthy subjects aged 23-95 years old. Using a double staining immunofluorescence and flow cytometry analysis, we have determined the percentages of cells expressing HLA class-I and HLA-DR antigens. The number of antigenic sites expressed per cell were evaluated for HLA-ABCw, HLA-A, HLA-B, HLA-DR locus with a flow cytometry quantification technique. With advancing age, we observed: (i) a significant decrease of the percentage of T cells and B cells expressing HLA-A products; (ii) a decrease of the number of HLA class-I antigenic sites expressed per cell on the three populations tested, predominantly on B cells and in a locus-dependent fashion; (iii) a decrease of the number of HLA-DR molecules expressed per T cell, although the percentage of T cells expressing DR products was increased; (iv) a significant diminution of the percentage of B cells expressing HLA-DR molecules, without changes of the number of HLA-DR antigenic sites per cells. These changes in HLA expression with increasing age could contribute to the decreased level of immunologic responsiveness observed with ageing and contribute to the modification of antigen recognition.     

Isolation of principal and basal cells from the epithelium of the hamster caput epididymidis by unit gravity sedimentation

A technique for the isolation of principal and basal cells from the epithelium of the hamster caput epididymides by unit gravity sedimentati on is described. The technique enzymatically disaggregates cells comprising the caput epididymides, and the resulting mixture of disperse d cells is separated by sedimentation in a shallow bovine serum albumin gradient at unit gravity into populations of spermatozoa, erythrocytes and several nucleated types. The separated somatic cell types and the homogeneity of each population were identified by light and electron microscopy. The purest fractions of the 6 populations, from smallest to largest, contained an average of 84% erythrocytes, 76% basal cells, 82% fibroblasts and intraepithelial lymphocytes, 68% small principal cells and 34% smooth muscle cells or 58% large principal cells. Cell viability following sedimentation was excellent, as concluded from elect ron micrographs revealing adenosine triphosphate content and fine struct ure. This technique should enable critical analyses of epididymal function in isolated epithelial cells.     

Lectins and antibodies to blood group antigens as markers for the basal cells of the human respiratory epithelium

We evaluated personality change following head injury in 68 patients at 6 months postinjury using the NEO Five-Factor Inventory to assess the five personality dimensions of the Five-Factor Model of Personality. All items had to be rated twice, once for the preinjury and once for the current status. Twenty-eight trauma patients with injuries to other parts of the body than the head were used as controls. For the head-injured group, 63 relatives also completed the questionnaire. The results showed no differences between the ratings of head-injured patients and the ratings of trauma control patients. Both groups showed significant change in the personality dimensions Neuroticism, Extraversion, and Conscientiousness. Compared to their relatives, head-injured patients report a smaller change in Extraversion and Conscientiousness. Changes were not reported on the Openness and Agreeableness scales, by neither the head-injured or their relatives, nor by the trauma controls.     

High levels of interleukin-8 in the blood and alveolar spaces of patients with pneumonia and adult respiratory distress syndrome

There is ample experimental evidence that polymorphonuclear neutrophils (PMN) play a critical role in the pathogenesis of the adult respiratory distress syndrome (ARDS). Since interleukin-8 (IL-8) is a strong chemotactic factor for PMN, we measured IL-8 levels in plasma and bronchoalveolar lavage (BAL) fluid of 18 patients, 12 with ARDS and 6 with severe pneumonia uncomplicated by ARDS, all of whom had an increased number of PMN in BAL fluid. Seven healthy subjects served as controls. We found elevated levels of IL-8 in the alveolar spaces of all patients tested. Elevated BAL IL-8 levels were related to a fatal outcome and the presence of shock and correlated with a general clinical severity index (simplified acute physiological score). BAL fluid levels of IL-8 were significantly higher in patients with ARDS than in patients with pneumonia. In plasma, IL-8 levels were increased similarly in all patients and did not correlate with survival or the presence of shock. The BAL fluid-to-plasma ratio of IL-8 was significantly greater than that of tumor necrosis factor alpha, indicating higher local production of IL-8. Moreover, the presence of a primed subpopulation of blood PMN with respect to H2O2 production indicates that IL-8 may contribute to the neutrophil-mediated process in the pathogenesis of ARDS and pneumonia.     

Immunohistochemical distribution of lymph capillaries and blood capillaries in the synovial membrane in cases of internal derangement of the temporomandibular joint

The distribution of lymph capillaries and blood capillaries in the synovial membrane was examined immunohistologically with anti-human collagen IV antibody and anti-human von Willebrand factor in 26 human temporomandibular joint (TMJ) samples comprising discs with adjoining synovial membrane from 10 control TMJs and from 16 TMJs with internal derangement. Three different distribution types were observed in the synovial membrane. In the control samples, the occurrence of blood capillaries and lymph capillaries was rare. In mildly hyperplastic synovitis, lymph capillaries were observed just beneath the surface of the synovial membrane, whereas blood capillaries occurred in a little deeper layer of the synovial membrane. In a severely hyperplastic synovitis, both lymph and blood capillaries were observed frequently. The present results suggest that the different distribution patterns of lymph capillaries and blood capillaries reflect the degree of synovitis but can not be attributed to specific clinical symptoms.     

Developmental changes of neutral glycosphingolipids as receptors for pulmonary surfactant protein SP-A in the alveolar epithelium of murine lung

A dramatic change in the glycosphingolipid composition in murine lung occurred between 1 day and 1 week after birth. GlcCer and LacCer were the predominant neutral glycosphingolipids prenatally and 1 day after birth, and the concentrations of globo- and ganglio-series glycosphingolipids increased abruptly from 1 week after birth, reaching maxima at 2-3 weeks. To explore the functional significance of the change, we examined the role of neutral glycosphingolipids as receptors for the murine pulmonary surfactant protein, SP-A, and found that SP-A bound to LacCer, Gg3Cer, and Gg1Cer, but not to Gb3Cer, Gb4Cer, IV3GalNAc alpha-Gb4Cer, sulfatide, or several gangliosides. On TLC-blotting with 125I-labeled SP-A, the binding of SP-A to Gg3Cer and Gg4Cer was 5 times higher than that to LacCer, and on immunohistochemical staining Gg4Cer and Gg3Cer was mainly observed in the alveolar epithelium. Thus, the capacity to retain SP-A of glycolipid receptors per gram dry weight of lung at 1 week after birth was 1.6 times higher than that at 1 day after birth, and reached a maximum 3 weeks after birth. These findings suggest that the enhanced synthesis of the ganglio-series neutral glycosphingolipids 1 week after birth results in an increase in the binding capacity for SP-A on the epithelial cell surface of alveoli.     

Analysis of testicular migration during the fetal period in humans

PURPOSE: We present an analysis concerning the testicular migration and its position correlated to body weight, crown-rump length and gestational age during the fetal period in humans without congenital abnormalities. MATERIALS AND METHODS: We studied bilaterally 142 testes taken from 71 fresh human fetuses between 10 and 35 weeks after conception. The fetuses were also evaluated in regard to crown-rump length and body weight. The position of the testes was correlated to the fetal parameters. RESULTS: In 37 fetuses (74 testes) at 10 to 23 weeks after conception only 7 testes (9.45%) had migrated from the abdomen and were situated in the inguinal canal, in 19 fetuses (38 testes) at 24 to 26 weeks after conception 22 testes (57.9%) had migrated from the abdomen and in 9 fetuses (18 testes) at 27 to 29 weeks after conception only 3 testes (16.7%) had not descended to the scrotum. The testes had not descended into the scrotum in any fetus weighing 990 gm. or less and with a crown-rump length of 24.5 cm. or less. On the other hand, in all fetuses weighing more than 1,220 gm. and with a crown-rump length of more than 27.5 cm. the testis was in the scrotum. CONCLUSIONS: Until 23 weeks after conception the majority of testes remain in the abdomen. The more intense migration of the testes through the inguinal canal occurred between 21 and 25 weeks after conception. After 30 weeks after conception all testes were descended to the scrotum in all fetuses.     

Taste disks are induced in the lingual epithelium of salamanders during metamorphosis

We have established a practical method of complete high-resolution typing for all HLA-A alleles using the polymerase chain reaction (PCR)-restriction fragment-length polymorphism (RFLP) technique combined with allele group- and sequence-specific amplification. The second and third exons of the HLA-A gene, in which most allelic variations are observed, were separately amplified by PCRs with 3 and 4 group-specific primer pairs, respectively. Each PCR-amplified product was digested by allele-specific restriction endonucleases and then subjected to electrophoresis on a 10% polyacrylamide gel. In this way, 62 out of 79 HLA-A alleles could be discriminated by the RFLP patterns derived from the genetic polymorphism in the exon 2 and 3 domains. The remaining 17 alleles could be defined unequivocally by either PCR-RFLP analysis after exon 4 amplification or PCR analysis with sequence-specific primers (SSP). By this method, complete HELA-A genotyping for all homozygous and heterozygous combinations can be accomplished, establishing technically simple, economical and practical routine typing of the HLA-A gene, especially for small samples.     

Salt and water transport across the alveolar epithelium in the developing lung: correlations between function and recent molecular biology advances (Review)

Significant progress have been made in understanding the mechanisms of alveolar fluid clearance at the time of birth and the transition from placental oxygenation to air breathing. During fetal life, the mammalian lung is a fluid filled secretory organ that fills no respiratory function. Its potential air spaces are filled with fluid that is actively secreted in response to an osmotic force generated by Cl(-)-secretion and the fluid-filled lung is necessary for a proper development of the air-breathing lung. As term approaches, net Cl(-)-secretion decreases, which is accompanied by a decreased secretion rate of the fluid into the air spaces. Concomitantly with the decreased Cl(-)-secretion, the alveolar epithelium begins to absorb Na+ to prepare for fluid absorption and the air breathing life. The causes for the decreased Cl(-)-secretion and the beginning of the Na+ absorption are not clear. Alterations in the hormonal milieu of the lung as well as changes in plasma stress hormone levels have been suggested to play roles. The switch from a placental oxygenation to pulmonary oxygenation requires that the fluid in the air spaces be rapidly removed from the lung lumen. Recent studies have demonstrated that removal of the alveolar fluid at birth is regulated via endogenous plasma epinephrine in the newborn. Molecular, cellular, and whole animal in vivo studies have demonstrated that fluid absorption at birth is related to expression and function of the epithelial sodium channel (ENaC). Several different in vivo and in vitro preparations have been used to investigate the mechanisms of alveolar fluid transport, primarily in adult lungs and have demonstrated that alveolar fluid absorption is driven by active Na+ transport. Both catecholamine-dependent and -independent regulatory mechanisms have been identified, probably acting on ENaC and other apical sodium channels and/or the basolaterally located Na+, K(+)-ATPase. Future studies are needed to integrate new insights to the molecular mechanisms behind fluid clearance with their function in both normal and pathological lungs.     

Endocytosis during postnatal differentiation in superficial cells of the mouse urinary bladder epithelium

This electron microscopical study was performed in order to follow the endocytic pathway of horseradish peroxidase and colloidal gold tracers and to determine the involvement of endocytosis in postnatal differentiation in superficial cells of the mouse urinary bladder epithelium. Morphometric analyses of late endosomes/multivesicular bodies from day of birth to day 25 were performed. The internalisation and intracellular transport of luminal plasmalemma to multivesicular bodies via endocytic vesicles, early endosomes and pleomorphic compartments was established. Dynamic changes in endocytic activity took place within the first few days of postnatal differentiation. During this period the number of multivesicular bodies changed in an inverse ratio to their size. After the third day endocytic activity gradually approached the low rate of adult urothelium.     

Fine structure of extracellular matrix and basal laminae in two types of abnormal collagen production: L-proline analog-treated otocyst cultures and disproportionate micromelia (Dmm/Dmm) mutants

The diagnostic implications of different procedures of DNA extraction were examined for the detection of HCMV DNA from sera and plasma of immunosuppressed patients. The detection limit of HCMV plasmid DNA from cell free seronegative plasma and serum by limiting dilution nested PCR decreased in the following sequence: phenol/chloroform > NaI-single tube method > proteinase K digestion equal to amplification of native sera and plasma. Nested PCR from native sera and plasma performed well and surpassed the proteinase K method in sensitivity for detection of serum DNAemia. Semi-quantitative determination of HCMV DNA titer present in native sera of immunosuppressed patients did not seem to be correlated to HCMV disease. When compared to the persistence of leukoDNAemia, the viral DNA titer in native plasma could only be observed in the acute phase of HCMV infection, an important phenomenon for diagnostic purposes. Correlation of serum DNAemia to virus culture revealed low positive and high negative predictive values. Predictive values of nested PCR from native sera for HCMV infection were not lower than those following organic DNA extraction. Despite its low correlation to viremia and virus isolation from any site, nested PCR from organic DNA extracts of serum or plasma is the most sensitive diagnostic tool of an ongoing HCMV infection. Additionally, semi-quantitative end point dilution nested PCR from native serum or plasma promises to be a rapid and easy tool for the monitoring of antiviral therapy.     

Electron microscopic observations on the elimination of the oocyte through the peritoneal epithelium in the neonatal mouse ovary

Six girls and one boy with cronic active hepatitis (CAH) of unknown etiology were between 9 and 15 years at the clinical onset of their illness. After beginning immunosuppressive therapy the course of their disease was followed from one to ten years. All had markedly increased IgG, high titres of smooth muscle antibodies (SMA) and antinuclear antibodies of IgG class in the earliest serum specimens tested. Therapy resulted in an improved sense of well-being and a decrease in SGOT, IgG and titres of SMA. Very high titres of measles antibodies were observed in all cases. In one of the cases CAH manifested itself after measles and in another after rubella infection. The first case in our series of patients died of liver failure after 5 years of illness. The other patients have survived and are able to live a normal life. The possibility of CAH should be considered when children develop symptoms of hepatitis. Longterm immunosuppressive treatment with regular clinical and laboratory evaluation is important. Estimation of titres of SMA is an additional parameter of value in following of the activity of CAH in these young patients.     

Transgene expression of steel factor in the basal layer of epidermis promotes survival, proliferation, differentiation and migration of melanocyte precursors

Mutations at the murine dominant white spotting (KitW) and steel (MgfSl) loci, encoding c-Kit receptor kinase and its ligand respectively, exert developmental defects on hematopoietic cells, melanocytes, germ cells and interstitial cells of Cajal. The expression patterns of steel factor (SLF) observed in the skin and gonads suggest that SLF mediates a migratory or a chemotactic signal for c-Kit-expressing stem cells (melanocyte precursors and primordial germ cells). By targeting expression of SLF to epidermal keratinocytes in mice, we observed extended distribution of melanocytes in a number of sites including oral epithelium and footpads where neither melanocytes nor their precursors are normally detected. In addition, enlarged pigmented spots of KitW and other spotting mutant mice were observed in the presence of the SLF transgene. These results provide direct evidence that SLF stimulates migration of melanocytes in vivo. We also present data suggesting that SLF does not simply support survival and proliferation of melanocytes but also promotes differentiation of these cells. Unexpectedly, melanocyte stem cells independent of the c-Kit signal were maintained in the skin of the SLF transgenic mice. After the elimination of c-Kit-dependent melanoblasts by function-blocking anti-c-Kit antibody, these stem cells continued to proliferate and differentiate into mature melanocytes. These melanoblasts are able to migrate to cover most of the epidermis after several months. The SLF transgenic mice described in this report will be useful in the study of melanocyte biology.     

Early and late acquisition of discriminative neuronal activity during differential conditioning in rabbits: Specificity within the laminae of cingulate cortex and the anteroventral thalamus.

Recorded multiple-unit activity of the circulate cortex and the anteroventral (AV) nucleus of the thalamus during discriminative conditioning of an avoidance response (locomotion) in 50 New Zealand White rabbits. Results indicate a greater unit response in cingulate cortex to the positive conditional stimulus (CS+; a tone paired with a footshock UCS) relative to the negative conditional stimulus (CS–; a tone randomly interspersed with the positive stimuli but never paired with the UCS). The majority of neuronal records obtained from the deep laminae of cingulate cortex manifested 1st neuronal discrimination in the session of 1st exposure to conditioning. However, the majority of neuronal records of the superficial laminae showed 1st discrimination at a late stage of training, during the session in which the criterion of behavioral discrimination was met. The late developing discriminative activity of the superficial laminae was coincident with the late developing discriminative activity of the AV thalamus. Once acquired, neuronal discrimination in cortex persisted throughout 600 msec after CS onset, and during 6 sessions of training of overtraining. Analysis of individual neuronal records suggested that the persistence during overtraining resulted from replacement of early fading neuronal discriminations by late neuronal discriminations. (44 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)