Displacement of gold marker in immunoelectron microscopy of human respiratory cilia

Preembedding immunogold electron microscopy was performed to evaluate the position of outer arm dynein heavy chains in normal human respiratory cilia. Anti-dynein antibody (AD2), which is specific for sea urchin sperm flagellar dynein heavy chains, was used as primary antibody. Direct cross-sections of cilia were selected, and the distance between the center of a cilium and the center of a colloidal gold particle attached to the cilium (X) was measured. The distance between the center of a cilium and the farthest edge of an outer dynein arm of the cilium was measured by ordinary electron microscopy (Yo) and by immunoelectron microscopy (Yi). X was significantly longer than Yo and Yi. If it is assumed that the structure of respiratory cilia is dense and that antibodies are located at the outer side of the actual position of the heavy chains, then the average distance difference of approximately 90-120 A may represent the length of two conjugated antibodies. This length should be kept in mind when performing immunoelectron microscopy. The data suggest that AD2 recognizes the outer arm dynein heavy chains of normal human respiratory cilia.

Downmodulation of IL-8 receptors, type A and type B, on human lung neutrophils in vivo

We examined the expression of interleukin (IL)-8 receptors (Rs), type A (IL-8-RA) and type B (IL-8-RB), on peripheral blood and bronchoalveolar lavage (BAL) fluid neutrophils; we also examined IL-8 and other chemoattractants in the epithelial lining fluid (ELF) of patients with chronic lower respiratory tract infection (CLI) to elucidate the in vivo regulation of IL-8Rs. Neutrophils were stained with monoclonal antibodies specific for IL-8-RA and IL-8-RB. We detected higher levels of IL-8 (81.6 +/- 25.4 ng/ml, mean +/- SE), leukotriene (LT) B4, and IL-1 beta in the ELF of the CLI patients than in their serum (P < 0.05). The expression of IL-8Rs on BAL neutrophils was significantly lower than that on peripheral blood neutrophils (P < 0.01 for both). In vitro analysis showed that low-level IL-8 (50 ng/ml) alone did not affect IL-8R expression but that it was downregulated by high-level IL-8 (500 ng/ml) alone and by low-level IL-8 in combination with LTB4 or IL-1 beta. Staurosporine reduced the downmodulation by low-level IL-8 plus LTB4 or IL-1 beta but not by high-level IL-8 alone. We speculate that pulmonary IL-8-RA and IL-8-RB may have been downmodulated by the combined effect of local chemoattractants through, in part, a protein kinase C-dependent mechanism.

Basaloid-squamous cell carcinoma of the floor of the mouth: characterization of a cell line

Since it was first described in 1986, basaloid-squamous cell carcinoma (BSC) has been considered a distinct variant of squamous cell carcinoma that occurs in a variety of anatomic sites, including the head and neck region. We report the characterization of the first cell line established from a basaloid-squamous cell carcinoma of the floor of the mouth. The cell line exhibited a highly invasive capacity, indicating that BSC has very aggressive behavior. This cell line may be a useful model for elucidation of the biological characteristics of BSC.

Localization of laminin subunits in the central nervous system in Fukuyama congenital muscular dystrophy: an immunohistochemical investigation

We have undertaken an immunohistochemical study of laminin subunits in the central nervous system (CNS) of fetuses and patients with Fukuyama congenital muscular dystrophy (FCMD) and of controls including five fetuses. Immunoreaction product deposits with antibodies to laminin alpha 1, alpha 2, beta 1 and gamma 1, and beta-dystroglycan were detected on the surface and vessels of the CNS of controls. No staining with anti-alpha-sarcoglycan antibody was detected in the CNS. Neurons and glia did not react with any of the antibodies used. In utero expression of laminin subunits and beta-dystroglycan seemed to be lower in the cerebrum than in the spinal cord. Moreover, immunostaining for laminin alpha 2 and beta 1 tended to be weak on the fetal spinal cord surface. Expression of laminin subunits and dystrophin-associated proteins in the CNS may be modulated during development, as in the skeletal muscle. The distribution of immunoreaction product deposits was basically the same in FCMD and controls, although laminin alpha 2 and beta-dystroglycan expression appeared to be decreased in the CNS of the FCMD cases. Defects of the pial-glial barrier of the fetal brain surface have been considered the main cause of micropolygyria in FCMD, and these observations suggest that the co-localization and secondary loss of these proteins in association with the unknown product(s) of the FCMD gene might be involved in the CNS lesions of this disorder.

Early ultrastructural changes in the central nervous system in Fukuyama congenital muscular dystrophy

Electron microscopy of the central nervous system surface structure is described in two fetuses with Fukuyama congenital muscular dystrophy (FCMD). In addition to relatively large surface defects, many minute defects less than several micrometers in size associated with protrusion of glial cytoplasm were observed in the cerebrum. These findings were considered to represent early changes prior to cortical dysplasia. The basement membrane adjacent to the defects showed amorphous, wavy, or whorled configurations, and gradually disappeared. The glial cytoplasmic membrane seemed to be relatively well preserved in some areas where the basement membrane disappeared. On the other hand, both the basement membrane and cytoplasmic membrane became indistinct irregularly in areas without defects, including the spinal cord; similar lesions were found in the skeletal muscle. These observations confirm previous observations concerning defects of the pial-glial barrier of the brain surface, and may suggest the involvement of abnormal basement membrane or related structures, or both, in the genesis of the brain lesions of FCMD.

Flexor tendon ruptures caused by an intraosseous ganglion of the hook of the hamate

A rare case of pathological rupture of the flexor tendons of the small finger caused by an intraosseous ganglion of the hook of the hamate is described.

HSDJ, a human homolog of DnaJ, is farnesylated and is involved in protein import into mitochondria

The role of HSDJ, a human homolog of bacterial DnaJ and yeast YDJ1p/MAS5, in mitochondrial protein import was examined. Recombinant HSDJ was purified and an antibody was prepared. HSDJ mRNA was heat-induced in cultured cells. In pulse-labeling and chase experiments using COS-7 cells, the endogenous HSDJ homolog was prenylated. Transiently expressed HSDJ was also prenylated, whereas its mutant C394S in which cysteine of the "CaaX box" was mutated to serine, was not. HSDJ, but not C394S, synthesized in rabbit reticulocyte lysate was farnesylated. The HSDJ antibody inhibited import of ornithine transcarbamylase precursor (pOTC) into isolated mitochondria when added prior to pOTC synthesis, but not when added prior to import assay. In transient expression of pOTC in COS-7 cells, pOTC was synthesized and processed to the mature form with an apparent half-life of 2-3 min. Coexpression of HSDJ or C394S resulted in slight retardation of the pOTC processing. These results indicate that HSDJ is involved in an early step(s) of protein import into mitochondria.

Visualization of mitochondrial protein import in cultured mammalian cells with green fluorescent protein and effects of overexpression of the human import receptor Tom20

The presequence of the ornithine transcarbamylase precursor (pOTC) was fused to green fluorescent protein (GFP), yielding pOTC-GFP and pOTCN-GFP containing the presequence plus 4 and 58 residues of mature ornithine transcarbamylase, respectively. When GFP cDNA was transfected into COS-7 cells, the cytosol and nucleus were fluorescent. On the other hand, pOTC-GFP cDNA gave strong fluorescence of a unique mitochondrial pattern. After fractionation of cells expressing pOTC-GFP with digitonin, fluorescence was recovered mostly in the particulate fraction. Immunoblot analysis showed that processed GFP was present in the particulate fraction, whereas pOTC-GFP was recovered in both the soluble and particulate fractions. pOTC-GFP and pOTCN-GFP synthesized in vitro were imported efficiently into the isolated mitochondria. Single and triple amino acid mutations in the presequence resulted in impaired mitochondrial import and in a loss of mitochondrial fluorescence. Perinuclear aggregation of fluorescent mitochondria was observed when the human mitochondrial import receptor Tom20 (hTom20) was coexpressed with pOTC-GFP. Overexpression of hTom20 (not DeltahTom20, which lacks the anchor sequence) resulted in stimulated mitochondrial import of pOTC-GFP in COS-7 cells. When pOTC-GFP cDNA was microinjected into nuclei of human fibroblast cells, mitochondrial fluorescence was detected as early as 2-3 h after injection. These results show that GFP fusion protein can be used to visualize mitochondrial structures and to monitor mitochondrial protein import in a single cell in real time.

Participation of the import receptor Tom20 in protein import into mammalian mitochondria: analyses in vitro and in cultured cells

Requirement of the mitochondrial import receptor Tom20 in protein import into mammalian mitochondria was studied in vitro and in cultured cells. Import of human and rat pre-ornithine transcarbamylase (pOTC), pig pre-aspartate aminotransferase (pAAT) and rat serine: pyruvate aminotransferase (pSPT) was inhibited by delta hTom20 that lacks the NH2-terminal transmembrane domain of human Tom20 (hTom20). Import of these preproteins was also inhibited by anti-Tom20. The inhibitions by delta hTom20 and anti-hTom20 were the strongest for human pOTC, followed by rat pOTC, pAAT and pSPT. Coexpression of human pOTC and hTom20 in COS-7 cells followed by immunoblot analysis showed that overexpression of hTom20, but not delta hTom20, decreases production of mature OTC. In pulse-chase experiments, pOTC was synthesized and rapidly processed to the mature form. Coexpression of hTom20, but not delta hTom20, resulted in a decrease of pOTC processing, probably due to an imbalance of the normal stoichiometry of the receptor complex. These results show that both in vitro and in intact cells, Tom20 is involved in mitochondrial protein import in higher animals and that the requirement for Tom20 is different for different preproteins.

Fatal diffuse alveolar damage from bird fanciers' lung

A 68-year-old man, who had continuing exposure to budgerigars, developed fatal acute respiratory failure following years of slowly progressive pulmonary deterioration. His lung function was characterized first by mild airflow obstruction and later by progressive loss of lung volume. Computed tomography showed progressive development of pulmonary fibrosis and honeycombing. His serum disclosed precipitins to pigeon antigen. During his final illness his chest radiograph showed widespread patchy consolidation. At autopsy, his lungs revealed left lower lobe bronchopneumonia, fibrosis and honeycombing at the bases and widespread evidence of diffuse alveolar damage with organized exudate in some alveoli. To our knowledge, this is the second reported fatality due to acute alveolar injury in bird fanciers' lung.

Cardiac angiotensin converting enzyme and endothelin receptor in rats with chronic myocardial infarction

To ascertain the pathophysiological roles of the renin-angiotensin system and endothelin in heart failure and cardiac hypertrophy, we assessed changes in cardiac angiotensin converting enzyme (ACE) and endothelin-1 (ET-1) receptor using rats in which myocardial infarction was induced by left coronary ligation. The animals were decapitated 1 or 8 months after the operation. Cardiac ACE and ET-1 receptor were quantified by computerized in vitro autoradiography using 125I-MK351A (a lisinopril derivative) and 125I-ET-1. One month after myocardial infarction, cardiac weight and plasma atrial natriuretic peptide had increased in rats with infarction, compared to sham-operated controls, indicating the presence of chronic left ventricular dysfunction, although exchangeable body sodium and plasma renin activity were unchanged. Cardiac ACE increased markedly in the infarcted area and moderately in hypertrophied myocardium without any change in affinity compared to sham-operated rats. On the other hand, there was no change in cardiac ET-1 receptors in infarcted rats. The same results were found even at 8 months after myocardial infarction. The present study indicates that cardiac ACE may participate in tissue repair at the site of myocardial infarction and may also play a role in the pathophysiology of cardiac hypertrophy in rats with chronic heart failure. However, the present results do not reveal whether ET-1 receptor participates in the pathophysiology of cardiac hypertrophy in this model.

Clinical presentation of pulmonary tuberculosis associated with acquired immunodeficiency syndrome in metropolitan Tokyo

The clinical features of pulmonary tuberculosis associated with acquired immunodeficiency syndrome (AIDS) in Japan were surveyed utilizing questionnaires completed by 48 institutes around the Tokyo metropolitan area. We found 11 Japanese and six foreign patients. The average number of patients per institute was 0.37. The Japanese patients had advanced human immunodeficiency virus (HIV) infection. A middle aged man, with fever and cough, nonspecific chest X-ray infiltrates, decreased lymphocyte counts, and a negative tuberculin skin test was the typical presentation of the Japanese patients. The clinical diagnosis was often difficult. The smear positive rate was high among those from whom smears were obtained, suggesting high communicability. None of the isolates indicated multidrug-resistant tuberculosis at the time of diagnosis. In conclusion, sputum smear and culture remain the keys to diagnosing tuberculosis in patients with AIDS, although the clinical picture may be atypical for pulmonary tuberculosis.

A derivative of cationic antimicrobial protein attenuates lung injury by suppressing cell adhesion

Cationic antimicrobial protein of 18 kD (CAP18) was identified and purified from rabbit granulocytes and shown to inhibit various activities of lipopolysaccharide (LPS). We investigated the effect of a 32-amino-acid C-terminal fragment of CAP18 (CAP18-derived peptide, CDP) on the pathogenesis of acute lung injury caused by intravenous endotoxin. Guinea pigs were divided into six groups: (I) saline control (n = 8), (2) CDP-alone (n = 8), (3) LPS-alone (n = 8), (4) LPS+CDP0m (n = 8), (5) LPS+CDP10m (n = 8), and (6) LPS+CDP60m (n = 8). A CDP dose of 0.2 mg/kg was injected at various time points after LPS injection. Lung wet-to-dry weight ratio, [125I]albumin leakage in lung tissue and bronchoalveolar lavage (BAL) fluid, differential cell count in BAL fluid, and histopathologic features were examined 4 h after intravenous administration of 0.02 mg/kg of LPS. The LPS+CDP0m and the LPS+CDP10m groups showed significantly attenuated lung injury compared to that seen in the LPS-alone group, however the LPS+CDP60m group revealed no attenuation of lung injury. The accumulation of peripheral white blood cells into pulmonary vasculature was attenuated only in the LPS+CDP0m but not in the LPS+CDP10m groups. We examined the effect of CDP on the expression of adhesion molecules using human umbilical vein endothelial cells, the result of which showed that CDP suppressed the LPS-induced expression of adhesion molecules in a dose-dependent manner. We conclude that CDP attenuates inflammatory cell migration into alveoli resulting in the attenuation of lung injury.

[Role of adhesion molecules in an animal model of endotoxin-induced acute lung injury]

We studied the role of adhesion molecules in acute lung injury caused by lipopolysaccharide (LPS). Forty-eight female guinea pigs were divided into three groups: saline (n = 12); B464, an LPS antagonist, (0.2 mg/kg i.v.) (n = 12); LPS (0.02 mg/kg i.v.) (n = 12); and LPS + B464 (n = 12). The numbers of polymorphonuclear cells (PMN) in blood sampled over 4 hours were counted. Accumulation of PMNs in the lungs was determined by counting the number of PMNs in lung-tissue samples fixed for light-microscopic examination. The lung wet-to-dry weight ratio and the 125I-albumin tissue-to-plasma ratio were used to assess lung injury. Human umbilical-vein endothelial cells were treated with B464 and then stimulated with either LPS or tumor necrosis factor. Expression of ICAM-1 and ELAM-1 was estimated by enzyme-linked immunosorbent assay. After LPS injection, light microscopy revealed decreases in peripheral PMN counts, and accumulation of PMNs in the lungs. Increases in the two indices of lung injury were also observed. These changes were attenuated by prior treatment with B464. The LPS-induced increases in ICAM-1 and ELAM-1 expression were dose-dependently suppressed by B464. These results suggest that pulmonary accumulation of activated PMNs plays an important role in LPS-induced lung injury.

Serum MIP-1 alpha and IL-8 in septic patients

We studied blood MIP-1 alpha and IL-8 in 38 septic patients and 5 healthy volunteers. Both chemokines were undetectable in the healthy volunteers. In sepsis, serum MIP-1 alpha was detected in 45% of the patients and Il-8 in 84%. The levels of MIP-1 alpha, but not of IL-8, correlated with CRP, IL-6 and TNF alpha levels. Complications, including various organ failures and mortality, showed no correlation with serum MIP-1 alpha levels. In contrast, we found increased levels of serum IL-8 in septic patients with disseminated intravascular coagulation, central nervous system (CNS) dysfunction or renal failure, and the mortality rate was higher in the IL-8 detectable group than in the IL-8 undetectable group (50% vs 0%, p < 0.05). In conclusion, the production of both MIP-1 alpha and IL-8 was increased and initially detectable levels of circulating IL-8 predicted high mortality in sepsis.

OBJECTIVE

To determine the significance of the C-C chemokine MIP-1 alpha and the C-X-C chemokine IL-8 in sepsis.

DESIGN

Prospective study.

SETTING

Clinical investigation, emergency department and general intensive care unit of university hospital.

PATIENTS AND PARTICIPANTS

38 septic patients and 5 healthy volunteers were studied. Sepsis was diagnosed following the criteria formulated by ACCP/SCCM.

INTERVENTIONS

10-20 ml of blood was drawn from each patient at the time of initial diagnosis of sepsis.

MEASUREMENTS AND RESULTS

MIP-1 alpha and IL-8 were determined by sandwich ELISA. Both chemokines were undetectable in the healthy volunteers. In sepsis, serum MIP-1 alpha was detected in 45% of the patients and IL-8 was detected in 84%. The levels of MIP-1 alpha, but not of IL-8, correlated with CRP, IL-6 and TNF alpha levels. Complications, including various organ failures and mortality, showed no correlation with serum MIP-1 alpha levels. In contrast, we found increased levels of serum IL-8 in patients with disseminated intravascular coagulation (DIC) (p < 0.05), central nervous system (CNS) dysfunction (p < 0.05), renal failure (p < 0.01) and the mortality rates were higher in the IL-8 detectable group than in the IL-8 undetectable group (50% vs 0%, p < 0.05).

CONCLUSIONS

The production of MIP-1 alpha and IL-8 was increased in sepsis. Furthermore, an initially detectable level of circulating IL-8, but not MIP-1 alpha, predicted a high mortality in sepsis diagnosed according to the ACCP/SCCM criteria.

Protective effect of B464, a lipid A analog, on endotoxin-induced cellular responses and acute lung injury

B464 is a novel synthetic analog of lipid A, a toxic component of endotoxin (LPS; lipopolysaccharide). We investigated the effects of B464 on both LPS-induced cellular responses in vitro and acute lung injury in vivo. In the in vitro study, B464 inhibited tumor necrosis factor-alpha (TNF-alpha) production from human monocytes, priming and stiffening of neutrophils, and expression of adhesion molecules on endothelial cells induced by LPS. We then studied the effects of B464 pretreatment on acute lung injury elicited by intravenous LPS administration in vivo. Guinea pigs were divided into saline control, B464 alone, LPS alone, and LPS + B464 groups. Animals were observed for 4 h after LPS administration, and lung injury was evaluated by extravascular lung water, 125I-albumin leakage in lung tissue, and lung neutrophil accumulation. In the LPS alone group, rapid and sustained peripheral neutropenia (p < 0.001 versus saline at 15 min and at 1, 2, and 4 h), an increased plasma TNF-alpha concentration (p < 0.005 at 1 h), and increases in lung injury parameters (p < 0.05) were observed. In the LPS + B464 group, no changes were observed in either plasma TNF-alpha or lung injury parameters. Transient peripheral neutropenia and subsequent rapid recovery (p > 0.05, p < 0.001, p < 0.01, and p > 0.05 at 15 min and 1, 2, and 4 h, respectively) were observed in the LPS + B464 group. These in vivo data, together with in vitro evidence of suppressed cellular responses, suggest that B464 (1) inhibits neutrophil accumulation in lung tissue, and (2) attenuates the development of acute lung injury by blocking the activation of neutrophils and mononuclear cells as well as the interaction between neutrophils and endothelial cells.

[Measurement of the common carotid arterial flow during parabolic flight in the anesthetized rat]

To measure the blood flow of a common carotid artery (CCA) during parabolic flight in the rat, we developed an animal double hold box (ADHB) made of styrene expanded form for the anesthetized rat to keep the animal at a proper posture in an aircaft. Twelve anesthetized rats weighing 291-342 g were surgically operated to mount a ultrasound flowmeter probe (1 mm size,1RS:Transonic Systems Inc.) around the right CCA and to insert a catheter into the right axillar artery for blood pressure measurement. These animals were held comfortably in ADHBs which were placed on the rack installed in the aircraft (MU-300). A total of 27 parabolic flights was performed and the blood flow was measured accurately in 9 rats. This special animal holding facility is useful for various types of animal experiments in an aircraft.