Choroidal Circulatory Disturbance in Ocular Sarcoidosis Without the Appearance of Retinal Lesions or Loss of Visual Function

BACKGROUND

Birdshot chorioretinopathy, acute posterior multifocal placoid pigment epitheliopathy, and retinal pigment epithelial detachment have been reported as rare manifestations associated with sarcoidosis, suggesting that ocular sarcoidosis may affect the choroidal circulation. We report a case of ocular sarcoidosis representing a choroidal circulatory disturbance without the appearance of retinal lesions or loss of retinal function.

CASE

A 20-year-old woman was referred with blurred vision in the left eye. Inflammatory change in the anterior segment of the eye was noted with multiple nodules on the iris.

OBSERVATIONS

Hematological examination revealed elevated lysozyme levels. Bilateral hilar lymphadenopathy was noted on chest X-ray. Specimens obtained by transbronchial lung biopsy revealed granuloma with Langhans giant cells, which led to the diagnosis of sarcoidosis. The eye was treated with topical steroid. The symptoms and the inflammatory change in the anterior segment disappeared within 10 days. However, despite the normal appearance of the ocular fundus, fluorescein angiography revealed multiple puncta of hyperfluorescence. In indocyanine green angiography, a filling delay was noted in the area corresponding to the punctate lesions. Static visual field testing and multifocal electroretinography showed no significant changes. At the last visit, 15 months after the left eye became asymptomatic, the choroidal lesions had disappeared with no residual alteration of the funduscopic appearance or visual function.

CONCLUSIONS

This case indicates that choroidal circulatory disturbance can underlie ocular sarcoidosis even in the absence of funduscopically detectable lesions and loss of visual function.

[Relationship between epithelial-immunologic cells transdifferentiation and pseudoepitheliomatous granuloma lesion]

OBJECTIVE

Inappropriate treatment at early stage of wound could result in the formation of pseudoepitheliomatous granuloma (PEG). The correlation of abnormal transdifferentiation of epithelial cells to immunologic cells and the occurrence of PEG lesion was investigated.

METHODS

Morphological change of epithelial tissue was observed with histopathology in 11 specimens of PEG lesions and 6 specimens of normal skins from PEG edge (PEG-N) from 11 patients with damaged skin. The expression characteristics and distribution of pan-cytokeratin (CKp), IV type collagen, laminin (LM), epithelial cadherin (E-Cad), beta-catenin (beta-Cat), focal adhesion kinase (FAK), stem cell factor (SCF) and its receptor-c-Kit, proliferating cell nuclear antigen(PCNA), and cluster of differentiation-14 (CD14), CD68 and mast cell tryptase (MCT) in PEG were detected with the immunohistochemical and the indirect immunofluorescent double-staining.

RESULTS

In comparison with PEG-N, epithelial tissue take on squamous metaplasia, and stroma was infiltrated with intensive microvessels and inflammatory cells in the PEG lesion. Poor epithelial basal layer constitution, basal polarization, and migration of basal cells to stroma could be observed. In the ultrastructure, the loose intercellular junction of basal cells and the increased nucleus/cytoplasm ratio and intercellular space could be observed, neonatal monocytoid cells and macrophages and mast cells as a exuviate-like manner brooded from cytoplasm of original epithelial cells and basement membrane. protein expression of CKp and E-Cad by basal cells was significantly decreased, and the IV type collagen and LM protein could not be found in basement membrane of identical locus. By contrast, the immunoreactivity of beta-Cat and FAK was apparently increased. In addition, CD14(+) monocytes, CD68(+) macrophages, MCT(+) mast cells and CD68(+)/MCT(+) cells with various size, and these cells of stronger immuno-staining of SCF, c-Kit and PCNA antigen could be found in epithelial tissue and stroma.

CONCLUSION

Epithelial cells in PEG related to wound are characteristized by transdifferentiation of epithelial cells to immunologic cells, wich may be associated with local infectious and inflammatory reaction, ultimately resulting in enhancement the ratio of beta-Cat/E-Cad signal and activation SCF-c-Kit signal pathway. The phenomena of transdifferentiation epithelial cells in the PEG lesion will help to recognize of the neoplatic immune and trauma repair mechanism.

Vasectomy reversal and spermatic granuloma: experimental investigation

The aim of our study was to investigate the healing process after vasectomy reversal, comparing two suturing techniques. Eighty Wistar rats received a two-layer vaso-vasostomy on the right side, and 40 of them also received a single-layer vaso-vasostomy on the left side. Twenty rats each time were sacrificed at 30, 45, 60, and 90 days. Results were evaluated in order to compare the two techniques used and to describe the progression of healing, with special reference to anastomotic patency rate, histologic aspect of the epididymus and testicle, and the presence and size of spermatic granuloma. We observed 45% patency with the double-layer technique compared to 20% with the single-layer technique. The testicle appeared atrophic in 20% of double-layer cases compared to 40% of single-layer cases. Comparison over time showed a progressive increase in patency of the anastomosis, reduction of spermatic granuloma, and regression of testicular damage. Our results show the superiority of the double-layer technique, and contribute to an understanding of the role of two different suturing techniques in the outcome of vasectomy reversal.

T cell contributions to the different phases of granuloma formation

Granulomatous inflammation is a form of delayed type hypersensitivity reaction that is involved in protection against chronic infections. Granulomatous inflammation can also occur without any clear inciting stimulus such as in sarcoidosis. An in depth knowledge of granuloma formation is essential to our understanding of protection against chronic infection as well as the dysregulation which occurs in granulomatous diseases of unknown origin. Granuloma formation is a complex and dynamic process involving the recruitment and coordination of diverse cell types. This review is focused on the important roles that T cells play in initiating and building the granuloma as well as in mediating effector functions and eventually resolving granulomatous inflammation. CD4(+) T cells emerge as the central mediators of this process, with T cells from other subsets also participating in the later phases of granuloma formation.

Granulomatous liver disease and cholestasis

Development of hepatic granulomas, especially those located within portal tracts, is associated with injury to septal and interlobular bile ducts. Dysfunction of the bile ducts in turn leads to cholestasis,and ongoing damage by the granulomatous inflammation eventually results in ductopenia. A multitude of causes of hepatic granulomas have been described over the last few decades. Diligent and prioritized search for cause of hepatic granulomas should proceed within the environmental and epidemiologic context of a given patient. The therapeutic approaches, including amelioration of the cholestatic syndrome, are often determined by successful identification of specific etiologic factors causing the granulomas in the liver.

IL-13 receptor alpha 2 down-modulates granulomatous inflammation and prolongs host survival in schistosomiasis

An important feature of many chronic parasitic infections is the ability of the invading pathogen and host to establish a compromise, which ensures successful parasitism without killing the infected host. For many helminth infections, down-modulating the immune response is critical because persistent inflammation can become more damaging to the host than the invading pathogen itself. Such is the case with schistosomiasis mansoni, where chronic granulomatous inflammation in the liver causes portal hypertension, porto-pulmonary shunting, bleeding from collateral bypass vessels, and eventual death if not suppressed effectively. CD4(+) T helper type 2 cells (Th2) (secreting IL-4, IL-5, and IL-13) characterize the host response after Schistosoma mansoni infection, and recent studies have identified IL-13 as the principal mediator of hepatic fibrosis. Here, we show that the IL-13 receptor alpha 2 (IL-13R alpha 2) is a critical mediator of immune down-modulation, identifying the receptor as a life-sustaining off signal for chronic and pernicious inflammation in schistosomiasis.

Association between skin parasitism and a granulomatous inflammatory pattern in canine visceral leishmaniosis

In this work we examined 76 stray dogs from an area of endemic visceral leishmaniosis, in order to determine whether the presence of skin inflammation or a specific inflammatory pattern could be taken as indicative of infection with Leishmania chagasi, and whether the parasite burden in the skin could be associated with the intensity or the nature of the inflammatory process. Inflammatory infiltrates were observed in the skin of 51 out of 55 animals with diagnosis of leishmaniosis, and in 17 out of 21 animals without signs of infection. Amastigotes were identified in the skin of 29 out of the 55 animals with diagnosis of leishmaniosis. Granuloma and a monomorphic macrophage inflammatory infiltrate, and not a mixed focal or mixed diffuse inflammation, were significantly associated with skin parasitism, both in terms of frequency ( P=0.015 in the Chi-square test) and intensity ( P=0.005 in the Kruskal-Wallis test). A low parasite burden was associated with a multifocal inflammatory pattern.

Epileptogenic activity of granulomas associated with murine cysticercosis

Neurocysticercosis, caused by Taenia solium, is a common cause of neurologic disease in developing countries and among immigrants to the United States. Seizures are the most common clinical manifestation of neurocysticercosis. Imaging studies of patients with seizures from neurocysticercosis typically reveal evidence of an inflammatory reaction associated with the parasite or calcified granulomas. This study investigated whether a substance produced by the host granulomatous reaction to the dying parasite, in a mouse model of the infection, is sufficient to induce epileptiform activity. Granulomas associated with Taenia crassiceps cysticerci were removed from the peritoneal cavity of infected mice. One piece of the granuloma was used for blinded histological staging of the dying parasite. The second piece was used to generate extracts, which were injected into the hippocampus of an anesthetized Sprague-Dawley rat. Positive controls included animals injected with kainic acid, picrotoxin, or bicuculline. Seizures were recorded after injection of extracts from 6 out of 6 early stage granulomas, but only 1 out of 9 late stage granulomas. Injections of buffered saline, extracts from non-stimulated mouse spleen cells, and homogenates of viable parasite material caused no epileptiform activity. The data suggest that a substance in the granulomas early in the inflammatory response to the dying parasite is capable of inducing seizure activity. Further experiments are needed to dissect out the exact seizure mediator in the granuloma extracts.

Clinical characteristics, prevalence, influence on sow performance, and assessment of sow-related risk factors for granulomatous mastitis in sows

OBJECTIVE

To determine the prevalence and clinical appearance of granulomatous mastitis in sows, to identify sow-related risk factors for development of granulomatous mastitis, and to explore the manner in which the disease influences sow performance.

ANIMALS

1,254 sows from 76 herds.

PROCEDURE

A clinical examination was performed at time of weaning and 7 days later. In addition, some sows were reexamined at time of weaning in the subsequent lactation. Data were collected on sow performance.

RESULTS

At time of weaning, 205 of 1,254 (16%) sows had granulomatous mastitis, and 7 days later, the prevalence was 19%. Variation between herds was large (0 to 50%). In most of the affected sows (156/205 176%]), only 1 mammary gland was affected. Parity, duration of lactation, and number of teat wounds were identified as risk factors for development of the disease. In 264 of 559 (47%) sows (38/104 [37%] mammary glands), a granuloma recurred in the subsequent lactation. Risk for recurrence was related granuloma appearing in multiple form but not to granuloma size. Affected glands were less distended in the subsequent lactation, suggesting lower milk production. Litter size appeared to be negatively affected by the disease.

CONCLUSIONS AND CLINICAL RELEVANCE

Granu lomatous mastitis is a common disease in sow herds maintained on straw bedding and in group housing, and it has negative effects on sow productivity. A thorough description of the clinical appearance of the disease and the identification of risk factors should contribute to development of relevant control measures.

Transient granulomatous inflammation of the hand

We present a granulomatous inflammatory tumour of the hand in a fit 26-year-old man. The lesion resolved spontaneously within a month of presentation. Whilst the true nature of this inflammatory lesion remains unknown the case highlights the importance of thorough investigation of all deep-seated soft tissue tumours of the hand prior to committing a patient to surgery.

Immunopathogenesis of pulmonary granulomas in the guinea pig after infection with Mycobacterium tuberculosis

Pulmonary tuberculosis in guinea pigs is similar to the disease in humans and is accordingly widely used as a model to test tuberculosis vaccines. The primary site of expression of acquired immunity and the hallmark of tuberculosis is the granuloma. Granuloma morphology is well described, but there is limited information regarding T-cell subset influx. We monitored the course of pulmonary tuberculosis in guinea pigs and observed four distinct immunohistopathological stages. In all stages there were similar numbers and arrangement of CD4 and CD8 T cells. There were only small numbers of apoptotic lymphocytes, scattered around and within the necrotic core, and acid-fast bacilli were visible both within macrophages and free within airway debris. A key finding of the study was the observation that the development of the necrotic core was an early event and almost certainly preceded the emergence of the acquired immune response. This in turn suggests that innate mechanisms are the basis of the early lesions and that subsequent acquired responses are unable to moderate them. This hypothesis differs from the current dogma that excessive activity of T cells mediates delayed-type hypersensitivity and that cellular cytolysis is the root cause of the necrosis.

T-lymphocytes and cytokines in sarcoidosis

In the last few years, a number of reports have clearly shown that pulmonary T lymphocytes have evolved a number of effector mechanisms to respond to foreign antigens, ranging from direct cytotoxicity mechanisms to secretion of lymphokines, that have the ability to activate themselves or other pulmonary immunocompetent cells. Furthermore, there is also evidence that lung T cells may have a role in the immunopathogenetic mechanisms taking place in the lung of most immune-mediated diffuse lung disorders. In this paper, we will review the current concepts on the recruitment, homing, and activity of T lymphocytes in the lower respiratory tract of patients with sarcoidosis. The relevant phenotypic and functional abnormalities detected on T cells in sarcoidosis will be discussed. Furthermore, we will comment recent findings on the ability of immunomodulatory molecules, such as proinflammatory cytokines, chemokines, and other cytokines, to regulate T-cell function in immune mechanisms leading to granuloma formation and maintenance.

Enhanced immune response in Mycobacterium bovis bacille calmette guerin (BCG)-infected IL-10-deficient mice

The role of the endogenous interleukin-10 (IL-10) in the control of Mycobacterium bovis Bacille Calmette Guerin (BCG) infection was assessed using IL-10-deficient (IL-10-/-) mice. Similar to wild-type (WT) mice, IL-10-/- mice were resistant to intravenous challenge with Mycobacterium bovis BCG. Significantly higher plasma concentrations of IL-12 and tumour necrosis factor (TNF) indicated an elevated protective immune response of IL-10-/- mice. Determination of bacilli burden in IL-10-/- mice showed accelerated clearance in the lungs, spleen and the liver in comparison to WT mice. Enhanced inflammation and a vigorous granulomatous response accompanied accelerated mycobacterial clearance. Immunohistochemical analysis of hepatic granulomas from IL-10-/- mice revealed augmented lymphocyte recruitment and macrophage activation, such as increased major histocompatibility complex (MHC) class II and inducible nitric oxide synthase (iNOS) expression. Further, it was found that enlarged granulomas persisted subsequent to mycobacterial clearance and failed to resolve in the absence of IL-10. In conclusion, endogenous IL-10 dampens the cell-mediated immune response to mycobacterial infection.

Sequential expression of the neuropeptides substance P and somatostatin in granulomas associated with murine cysticercosis

Neurocysticercosis, a parasitic infection of the human central nervous system caused by Taenia solium, is a leading cause of seizures. Seizures associated with neurocysticercosis are caused mainly by the host inflammatory responses to dying parasites in the brain parenchyma. We previously demonstrated sequential expression of Th1 cytokines in early-stage granulomas, followed by expression of Th2 cytokines in later-stage granulomas in murine cysticercosis. However, the mechanism leading to this shift in cytokine response in the granulomas is unknown. Neuropeptides modulate cytokine responses and granuloma formation in murine schistosomiasis. Substance P (SP) induces Th1 cytokine expression and granuloma formation, whereas somatostatin inhibits the granulomatous response. We hypothesized that neuropeptides might play a role in regulation of the granulomatous response in cysticercosis. To test this hypothesis, we compared expression of SP and expression of somatostatin in murine cysticercal granulomas by using in situ hybridization and immunohistochemistry. We also compared expression with granuloma stage. Expression of SP mRNA was more frequent in the early-stage granulomas than in the late-stage granulomas (34 of 35 early-stage granulomas versus 1 of 13 late-stage granulomas). By contrast, somatostatin was expressed primarily in later-stage granulomas (13 of 14 late-stage granulomas versus 2 of 35 early-stage granulomas). The median light microscope grade of SP mRNA expression in the early-stage granulomas was significantly higher than that in the late-stage granulomas (P = 0.008, as determined by the Wilcoxon signed rank test). By contrast, somatostatin mRNA expression was higher at later stages (P = 0.008, as determined by the Wilcoxon signed rank test). SP and somatostatin are therefore temporally expressed in granulomas associated with murine cysticercosis, which may be related to differential expression of Th1 and Th2 cytokines.

Granuloma formation, implications for the pathogenesis of vasculitis

The pathogenesis of granulomatous inflammation is complex and involves a variety of mechanisms acting in concert to bring about an inflammatory lesion that is able to contain and destroy intracellular pathogens. While this process is crucial to host defense, it is also a two-edged sword in that excessive or inappropriate granulomatous inflammation results in considerable damage to normal tissue. In recent years, there has been significant progress in dissecting the immunologic events involved in granuloma formation and maintenance. A better understanding of these events will allow us to more precisely modulate the granulomatous inflammatory response to the benefit of patients with both infectious and autoimmune diseases.

Management of cholesterol granulomas of the petrous apex based on clinical and radiologic evaluation

OBJECTIVE

The purpose of this study was to analyze the imaging characteristics of 12 cholesterol granulomas as a function of their clinical symptoms. The results of the different surgical approaches and the management of these lesions are discussed.

STUDY DESIGN

Retrospective case review.

SETTING

Five tertiary referral centers.

PATIENTS

Twelve patients managed for a cholesterol granuloma of the petrous apex.

INTERVENTIONS

All patients were evaluated via computed tomography and magnetic resonance imaging. Eight patients required surgical drainage: through a conservative approach in seven patients (infralabyrinthine, n = 5; infracochlear, n = 2) and a transotic approach in one patient. Clinical and radiologic follow-up without surgery was the mode of treatment for four patients. The mean follow-up period was 18 months for patients who underwent operations and ranged from 6 months to 10 years for patients without operations.

RESULTS

Four patterns of clinical symptoms were noted: retrocochlear signs by an involvement of the internal auditory meatus (n = 8), headaches by a traction of the dura (n = 4), serous otitis media by a compression of the eustachian tube (n = 2), and asymptomatic lesions with no involvement of the adjacent structures (n = 2). Hearing and facial functions were preserved in all the cases treated by a noninvasive procedure. No recurrence or complication was reported in the patients who underwent operations. None of the noninvasively treated patients with cholesterol granulomas showed significant enlargement on follow-up imaging.

CONCLUSION

Clinical manifestations of cholesterol granulomas depend on their anatomic location and the involvement of the adjacent structures. Aggressive lesions in patients with residual hearing can be drained via an infralabyrinthine or an infracochlear approach with minimal morbidity. Follow-up must be preferred for patients with nonaggressive lesions. Although magnetic resonance imaging provides a specific diagnosis tool for cholesterol granulomas, computed tomography is essential for an accurate evaluation of the location of the cyst and choice of the surgical procedure.

Surgical management of petrous apex cholesterol granulomas

OBJECTIVES

To review surgical approaches for drainage of petrous apex cholesterol granulomas, define the criteria for the selection of each approach, and identify factors affecting surgical outcome.

STUDY DESIGN

Retrospective chart review and follow-up survey questionnaire.

SETTING

Tertiary neurotologic referral center.

PATIENTS

Thirty-four patients who underwent surgical treatment for symptomatic cholesterol granulomas of the petrous apex, who had a minimum of 3 months of clinical follow-up care and, in some cases, postoperative radiologic follow-up studies.

INTERVENTION

Drainage with or without removal of the cyst lining was achieved through the transcanal infracochlear, transmastoid infralabyrinthine, middle fossa, translabyrinthine, and transotic approaches. Silastic catheters were used to stent drainage sites in some cases.

MAIN OUTCOME MEASURES

Relief of symptoms, postoperative cranial nerve function, clinical and radiologic recurrence, and need for further surgical intervention were evaluated. Imaging studies were reviewed to determine how anatomic information influenced surgical decisions and outcome.

RESULTS

Clinical improvement of symptoms was observed in 28 patients (82%), and recovery of cranial nerve function was observed in 8 of 9 affected individuals. Serviceable hearing was preserved in all but 1 patient. Five patients required revision surgery for recurrent symptoms and lesions. All 5 patients had undergone drainage procedures without the use of stents. The size of the lesion did not influence the surgical outcome.

CONCLUSIONS

Determination of the appropriate surgical approach to the petrous apex is based on hearing status in the affected ear and on the anatomic relationships between the lesion and the surrounding neurovascular structures. The translabyrinthine approach is useful in nonhearing ears. In hearing individuals, anatomy permitting, the transcanal infracochlear approach with stenting is the preferred approach for drainage of petrous apex cholesterol granulomas.

Abnormal pulmonary granuloma formation in osteopontin-deficient mice

Osteopontin is a novel cytokine that is expressed in pulmonary granulomatous disease such as sarcoidosis and tuberculosis. It can regulate macrophage and T cell migration, activation, and cytokine expression, yet its role in granuloma formation and evolution is unknown. We induced hypersensitivity pulmonary granulomas by embolizing Schistosoma mansoni eggs to the lungs of osteopontin-deficient (null mutant) mice and osteopontin-sufficient (wild-type control) mice. Granulomas from osteopontin-null animals were smaller at early time points and contained remarkably few macrophages and macrophage-derived epithelioid cells and giant cells. T cell accumulation was unaffected by osteopontin deficiency. These results demonstrate that osteopontin regulates macrophage accumulation during pulmonary granuloma formation, and may explain the impaired ability of osteopontin-deficient hosts to control mycobacterial disease.

Granulomatous hepatitis due to sarcoidosis: a case report

A Royal Australian Air Force transport pilot is discovered to have abnormal liver function tests during a routine aircrew medical examination. In the preceding 12 mo he had experienced minimal symptoms. Liver biopsy confirmed granulomatous hepatitis, the cause of which was determined to be sarcoidosis. Hilar and paratracheal lymphadenopathy were found on chest radiography. No overt evidence of other pulmonary, cardiac or ocular disease was found. This case illustrates the interesting problem of a clinically well aviator with biochemical abnormalities only, but at risk due to the potential presence of more widely disseminated sarcoidosis.

Altered extracellular matrix remodeling and angiogenesis in sponge granulomas of thrombospondin 2-null mice

The matricellular angiogenesis inhibitor, thrombospondin (TSP) 2, has been shown to be an important modulator of wound healing and the foreign body response. Specifically, TSP2-null mice display improved healing with minimal scarring and form well-vascularized foreign body capsules. In this study we performed subcutaneous implantation of sponges and investigated the resulting angiogenic and fibrogenic responses. Histological and immunohistochemical analysis of sponges, excised at 7, 14, and 21 days after implantation, revealed significant differences between TSP2-null and wild-type mice. Most notably, TSP2-null mice exhibited increased angiogenesis and fibrotic encapsulation of the sponge. However, invasion of dense tissue was compromised, even though its overall density was increased. Furthermore, histomorphometry and biochemical assays demonstrated a significant increase in the extracellular distribution of matrix metalloproteinase (MMP) 2, but no change in the levels of active transforming growth factor-beta(1). The alterations in neovascularization, dense tissue invasion, and MMP2 in TSP2-null mice coincided with the deposition of TSP2 in the extracellular matrix of wild-type animals. These observations support the proposed role of TSP2 as a modulator of angiogenesis and matrix remodeling during tissue repair. In addition, they provide in vivo evidence for a newly proposed function of TSP2 as a modulator of extracellular MMP2 levels.

Blockade of receptor for advanced glycation end-products restores effective wound healing in diabetic mice

Receptor for advanced glycation end-products (RAGE), and two of its ligands, AGE and EN-RAGEs (members of the S100/calgranulin family of pro-inflammatory cytokines), display enhanced expression in slowly resolving full-thickness excisional wounds developed in genetically diabetic db+/db+ mice. We tested the concept that blockade of RAGE, using soluble(s) RAGE, the extracellular ligand-binding domain of the receptor, would enhance wound closure in these animals. Administration of sRAGE accelerated the development of appropriately limited inflammatory cell infiltration and activation in wound foci. In parallel with accelerated wound closure at later times, blockade of RAGE suppressed levels of cytokines; tumor necrosis factor-alpha; interleukin-6; and matrix metalloproteinases-2, -3, and -9. In addition, generation of thick, well-vascularized granulation tissue was enhanced, in parallel with increased levels of platelet-derived growth factor-B and vascular endothelial growth factor. These findings identify a central role for RAGE in disordered wound healing associated with diabetes, and suggest that blockade of this receptor might represent a targeted strategy to restore effective wound repair in this disorder.

Evidence of IL-18 as a novel angiogenic mediator

Angiogenesis, or new blood vessel growth, is a key process in the development of synovial inflammation in rheumatoid arthritis (RA). Integral to this pathologic proliferation are proinflammatory cytokines. We hypothesized a role for IL-18 as an angiogenic mediator in RA. We examined the effect of human IL-18 on human microvascular endothelial cell (HMVEC) migration. IL-18 induced HMVEC migration at 1 nM (p < 0.05). RA synovial fluids potently induced endothelial cell migration, but IL-18 immunodepletion resulted in a 68 +/- 5% decrease in HMVEC migration (p < 0.05). IL-18 appears to act on HMVECs via alpha(v)beta(3) integrin. To test whether IL-18 induced endothelial cell tube formation in vitro, we quantitated the degree of tube formation on Matrigel matrix. IL-18, 1 or 10 nM, resulted in a 77% or 87% increase in tube formation compared with control (p < 0.05). To determine whether IL-18 may be angiogenic in vivo, we implanted IL-18 in Matrigel plugs in mice, and IL-18 at 1 and 10 nM induced angiogenesis (p < 0.05). The angiogenesis observed appears to be independent of the contribution of local TNF-alpha, as evidenced by adding neutralizing anti-TNF-alpha Ab to the Matrigel plugs. In an alternative in vivo model, sponges embedded with IL-18 or control were implanted into mice. IL-18 (10 nM) induced a 4-fold increase in angiogenesis vs the control (p < 0.05). These findings support a novel function for IL-18 as an angiogenic factor in RA and may elucidate a potential therapeutic target for angiogenesis-directed diseases.

Disturbance of the prejunctional modulation of cholinergic neurotransmission during chronic granulomatous inflammation of the mouse ileum

The effect of chronic granulomatous inflammation of the intestine was studied on the prejunctional modulation of cholinergic nerve activity in the mouse ileum. Contractions to carbachol (0.01 - 0.3 microM) and to electrical field stimulation (EFS, 0.25 - 8 Hz) of enteric neurons were higher in inflamed ileum as compared to control ileum. However, when the neurally-mediated contractions to EFS were expressed as percentage of the direct smooth muscle contraction to carbachol, the responses to EFS were similar in control and inflamed ileum. Atropine (1 microM) abolished all contractions to EFS and carbachol in control and inflamed ileum. DMPP (3 - 30 microM), a nicotinic receptor agonist, induced concentration-dependent contractions that were more pronounced in inflamed ileum as compared to control ileum. Hexamethonium (100 microM), a nicotinic receptor blocker, significantly inhibited the contractions to EFS in inflamed ileum but not in control ileum. In control ileum, histamine (10 - 100 microM) and the histamine H(1) receptor agonist HTMT (3 - 10 microM) inhibited the contractions to EFS concentration-dependently without affecting the contractions to carbachol. The inhibitory effect of histamine and HTMT was prevented by the histamine H(1) antagonist mepyramine (5 - 10 microM) but not by the H(2)- and H(3)-receptor antagonists cimetidine and thioperamide (both 10 microM). In chronically inflamed ileum however, histamine (10 - 100 microM) and HTMT (3 - 10 microM) failed to inhibit the contractions to EFS. The histamine H(2) and H(3) receptor agonists dimaprit and R(-)-alpha-methylhistamine did not affect the contractions to EFS in control and inflamed ileum. The alpha(2)-receptor agonist UK 14.304 (0.01 - 0.1 microM) inhibited the contractions to EFS in control and inflamed ileum without affecting the contractions to carbachol. The effect of UK 14.304 was reversed by the alpha(2)-receptor antagonist yohimbine (1 microM). The inhibitory effect of UK 14.304 on contractions to EFS was of similar potency in control and inflamed ileum. Our results suggest that the prejunctional modulation of cholinergic nerve activity by nicotinic and histaminic H(1) receptors is disturbed during chronic intestinal inflammation whereas the modulation by alpha(2)-receptors is preserved. Such a disturbance of cholinergic nerve activity may contribute to the motility disturbances that are often observed during chronic intestinal diseases in humans.

Effect of Schistosoma mansoni-induced granulomatous inflammation on murine gastrointestinal motility

In Schistosoma mansoni-infected mice, gastrointestinal transit was measured in vivo and the neuromuscular function of longitudinal muscle strips of inflamed ileum and noninflamed gastric fundus was assessed in vitro. Eight weeks after infection, the ileal wall was acutely inflamed, as shown by a mucosal inflammatory infiltrate, leading to an increase in mucosal thickness, in myeloperoxidase (MPO) activity, and in interleukin (IL)-1beta production. At that time, both gastrointestinal transit and in vitro ileal contractility were normal. Twelve weeks after infection, chronic granulomatous inflammation led to proliferation of the muscle layer and to a further increase in MPO activity, whereas IL-1beta production normalized. Gastrointestinal transit was decreased, whereas in vitro ileal contractility was increased irrespective of the contractile stimulus. In vitro incubation with IL-1beta (10 ng/ml for 60 min) significantly increased ileal contractility only at 8 wk after infection. Indomethacin, tetrodotoxin, and atropine had no differential effect on ileal contractility in controls and infected mice. In vitro contractility of noninflamed gastric fundus was normal both 8 and 12 wk after infection. We conclude that intestinal schistosomiasis 8 wk after infection is associated only with structural changes of the ileum, whereas 12 wk after infection, both structural and functional changes are present. These changes are characterized by increased ileal wall thickness, decreased gastrointestinal transit, and increased smooth muscle contractility restricted to the inflamed gut segment.

Sarcoidosis with granulomatous interstitial nephritis: report of three cases

Three cases of sarcoidosis with granulomatous interstitial nephritis are reported. Patients were all male and over 50 years of age. They simultaneously had evidence of multiorgan involvement of sarcoidosis including lung and skin and/or eye. In addition, distinct features were found in each case: a granulomatous infiltration mimicking unilateral renal tumor (case 1); renal insufficiency solely due to granulomatous interstitial nephritis (case 2); and renal insufficiency with calcemic nephropathy and granulomatous interstitial nephritis (case 3). Prednisolone therapy resulted in disappearance of the pseudotumor in case 1 and partial improvement of renal function in cases 2 and 3. In cases 2 and 3, however, plasma creatinine did not return to normal values and a second renal biopsy in case 2 demonstrated residual interstitial fibrosis and few granulomas, suggesting that steroid therapy did not achieve complete reversal of changes.

Structure-activity relationship of mycoloyl glycolipids derived from Rhodococcus sp. 4306

Novel mycoloyl glycolipids with short carbon chains were isolated and purified from Rhodococcus sp. 4306, a soil origin of Actinomycetales. Their chemical structures were identified as trehalose 6,6'-dimycolate (TDM), trehalose 6-monomycolate, glucose 6-monomycolate, mannose 6-monomycolate and fructose 6-monomycolate. The length of carbon chains and number of double bonds of mycolic acids were C(34), C(36)and C(38)saturated, monoenoic and dienoic molecular species, which were much shorter than those of Mycobacterium tuberculosis (C(78-88)monoenoic and dienoic). Among them, only TDM could induce prominent granulomatous inflammation of the lung and spleen in mice. By contrast, other mycoloyl glycolipids induced mild lesions. The small-sized TDM of Rhodococcus possessed granulomatogenic activity, however, the toxicity was much lower than that of M. tuberculosis. Rhodococcal TDM was composed of mycolic acid with the shortest carbon chains, when compared to granulomatogenic TDM of Mycobacterium, Nocardia and Rhodococcus reported previously. Our results imply that rhodococcal TDM is a pathogenetic factor similar to that of M. tuberculosis, although rhodococcal TDM exhibits low toxicity.

Chemokine receptor 1 knockout abrogates natural killer cell recruitment and impairs type-1 cytokines in lymphoid tissue during pulmonary granuloma formation

Mice with targeted mutation of chemokine receptor 1 (CCR1) were used to assess the contribution of CCR1 agonists to local, regional, and systemic inflammatory-related events during experimental pulmonary granuloma formation. Models of Th1 (type-1) and Th2 (type-2) cell-mediated lung granulomas were induced in wild-type (CCR+/+) and knockout (CCR1-/-) mice by embolizing Sepharose beads coupled to the purified protein derivative of Mycobacterium bovis or soluble antigens derived from Schistosoma mansoni eggs. Morphometric analysis indicated that granuloma sizes were unchanged in CCR1-/- mice, but flow cytometric analyses of dispersed granulomas revealed that natural killer cell recruitment to type-1 lesions was abrogated by 60%. Analysis of cytokine production by draining lymph node cultures showed altered expression in CCR1-/- mice characterized by reduced interleukin-2 and interferon-gamma in the type-1 response, and enhanced interleukin-5 and interleukin-13 in the type-2 response. Peripheral blood leukocytosis was also enhanced in the type-1 but not the type-2 response. These findings suggest that CCR1 agonists contribute to multiple immunoinflammatory events in the type-1 granulomatous response with natural killer cell accumulation being particularly sensitive to CCR1 disruption. Although functional efficacy of granulomas may be altered, chemokine redundancy and cytokine reserve seem to make the bulk of the exudative response resistant to CCR1 disruption.

Schistosoma mansoni egg-induced hepatic granulomas in mice deficient for the interferon-gamma receptor have altered populations of macrophages, lymphocytes and connective tissue cells

Systemic production and mobilization of inflammatory cells and formation of hepatic periovular granulomas were studied in Schistosoma mansoni-infected mice with deficient interferon gamma (IFN-gamma) receptor (IFN-gammaR(o/o)). The impaired IFN-gamma signaling did not cause a significant modification of the overall kinetics of inflammatory cells, but mutant mice developed smaller hepatic periovular granulomas with a two-fold reduction in all the cell lineages. In granulomas of normal mice, the fully differentiated macrophages were progressively predominant, whilst in IFN-gammaR(o/o) mice, the granulomas contained a higher percentage of immature and proliferating monocytes. Granulomas of IFN-gammaR(o/o) mice had an enhanced and accelerated fibrotic reaction, corresponding to an increased content of proliferative and activated connective tissue cells. Simultaneously, their granulomas had an increased ratio of T over B cells, with an increase in CD8(+) and a reduction in CD4(+) T cells. The functional IFN-gamma receptor was not required for initial recruitment of monocytes and lymphocytes into granulomas, but it was necessary for the maturation of macrophages, upregulation of major histocompatibility class 2 (MHC-II) expression and consequent stimulation of lymphocyte subpopulations depending upon the MHC-II-mediated antigen presentation.

The role of osteopontin in the development of granulomatous lesions in lung

Osteopontin (OPN) has been shown to be expressed by cells in granulomas of various origins, but whether it plays a functional role in granuloma formation is not known. Here we used a cardiomyopathic hamster (TO2) model, to test the hypothesis that OPN contributes functionally to granuloma development. We immunized cardiomyopathic and normal hamsters by subcutaneous injection of bovine serum albumin in complete Freund's adjuvant, and assessed various tissues for both OPN RNA expression and granuloma formation. Cardiomyopathic hamsters expressed OPN, and formed granulomatous lesions, in heart tissue in both immunized and untreated animals. In addition, immunization induced expression of OPN in lung and lymph nodes of cardiomyopathic (but not normal) hamsters, and also induced granuloma formation in these organs. To test whether OPN expression could play a functional role in inducing granulomas, we produced an adenoviral vector containing the murine OPN gene, and introduced this vector intratracheally into the lungs of normal hamsters. The OPN-containing vector, but not the control vector, induced pulmonary granuloma formation. These studies provided direct in vivo evidence that OPN can contribute functionally to the formation of granulomatous lesions, and suggest that OPN expression may be a common factor involved in formation of granulomas of various origin.

Different roles for nitrogen monoxide and peroxynitrite in lipid peroxidation induced by activated neutrophils

We studied the roles of nitrogen monoxide (NO&z.rad;) and peroxynitrite produced by the polymorphonuclear leukocytes (PMNs) isolated from an inflammatory exudate. PMNs were incubated either in a medium with a submicromolar concentration of iron or in a diethylenetriaminepenta-acetic acid (DTPA)-containing medium, and stimulated with phorbol 12-myristate 13-acetate (PMA) to generate free radicals. In both conditions superoxide anion (O(2)(*)(-)), NO&z.rad; and peroxynitrite were produced. In the presence of arachidonic acid, malondialdehyde (MDA) was generated. This MDA was generated in one of two way; the peroxynitrite iron-independent mechanism (40%) and the Fenton reaction, caused by free iron (60%). We also observed that the addition of L-arginine was followed by a 42% reduction in MDA, which can be explained by the antioxidant effect of NO&z.rad;. These results indicate that lipid peroxidation can occur in the absence of iron, through a peroxynitrite-mediated mechanism, and that NO&z.rad; may act as an antioxidant when it is produced in large amounts.

Detection of changes in lung tissue properties with multiple-indicator dilution

We evaluated the potential utility of a group of indicators, each of which targets a particular tissue property, as indicators in the multiple-indicator dilution method to detect and to identify abnormalities in lung tissue properties resulting from lung injury models. We measured the pulmonary venous outflow concentration vs. time curves of [14C]diazepam, 3HOH, [14C]phenylethylamine, and a vascular reference indicator following their bolus injection into the pulmonary artery of isolated perfused rabbit lungs under different experimental conditions, resulting in changes in the lung tissue composition. The conditions included granulomatous inflammation, induced by the intravenous injection of complete Freund's adjuvant (CFA), and intratracheal fluid instillation, each of which resulted in similar increases in lung wet weight. Each of these conditions resulted in a unique pattern among the concentration vs. time outflow curves of the indicators studied. The patterns were quantified by using mathematical models describing the pulmonary disposition of each of the indicators studied. A unique model parameter vector was obtained for each condition, demonstrating the ability to detect and to identify changes in lung tissue properties by using the appropriate group of indicators in the multiple-indicator dilution method. One change that was particularly interesting was a CFA-induced change in the disposition of diazepam, suggestive of a substantial increase in peripheral-type benzodiazepine receptors in the inflamed lungs.

Epithelioid cell granulomatosis of the lung: new insights and concepts

Our knowledge on epithelioid cell granulomatosis of the lung has been extended in recent years. New entities have been added, like zirconiosis; others like tuberculosis, mycobacteriosis and sarcoidosis have gained new interest, because molecular techniques allowed new insight into their pathogenesis and a more rapid and species-specific diagnosis. Experimental work in addition has added a lot of information about the network of cytokines and other inflammatory mediators responsible for granuloma formation. However, our knowledge of this network is still incomplete. Three types of agents are now known to cause epithelioid cell granulomas: infectious organisms (bacteria and fungi), products of plants and animals (pollen, sporangia, proteins), and metallic compounds. In addition, there is still a group of epithelioid cell granulomatoses with unknown etiology. Sarcoidosis, one of these granulomatoses has recently elicited an old controversy; by molecular techniques atypical Mycobacteria and Corynebacterium acne have been identified in sarcoid granulomas and a link to the etiology of sarcoidosis has been proposed. Whether these bacteria induce some cases of sarcoidosis by an allergic mechanism, has still to be proven.

Cells and cytokines involved in the pathogenesis of sarcoidosis

Granulomatous inflammation develops under the regulatory influence of cytokines produced by local mononuclear phagocytes, T cells, dendritic cells, fibroblasts, and other local cells. In sarcoidosis, granulomatous inflammation is characterized by dominant expression of T helper 1 (Th1) cytokines such as IFN gamma and interleukin (IL)-2 with low levels of expression of T helper 2 (Th2) cytokines such as IL4 and IL5. Recent studies show that the cytokine IL12, the most important regulator of Th1 immune responses currently known, is upregulated at sites of inflammation in sarcoidosis. In particular, enhanced expression of IL12 is seen in sarcoid lung and lymph node, along with dysregulated production of IL12 by stimulated and unstimulated sarcoid alveolar macrophages. The known dependence of granulomatous inflammation on type 1 cytokines (IFN gamma, IL12) in many experimental models of granulomatous disease makes it likely that these cytokines function in a similar fashion in the initiation and maintenance of granulomatous inflammation in sarcoidosis. Whether these same type 1 cytokines drive granulomatous inflammation in patients with extensive fibrocystic lung disease remains unknown. TGF beta, a known inhibitor of IL12 and IFN gamma production, is produced at higher levels by lung cells from those patients who undergo remission of their disease, suggesting that TGF gamma is important in downregulating granulomatous inflammation in sarcoidosis. These studies offer new insight into the molecular mechanisms of granuloma formation in sarcoidosis and provide a framework for developing new therapeutic strategies for the treatment of this disease.

Role of cytokines in the formation and downregulation of hepatic circumoval granulomas and hepatic fibrosis in Schistosoma mansoni-infected mice

Schistosoma mansoni infections are associated with a strong Th2 cytokine response. Treatment of mice with IL-12 or anti-IL-2 or anti-IL-4 before i.v. injection of eggs increased IFN-gamma production and downregulated Th2 responses and pulmonary granuloma size. Conversely, anti-IFN-gamma antibody treatment increased Th2 responses and granuloma size. Similar manipulation produced less dramatic results in infected mice. However, sensitization of mice with eggs + IL-12 before infection augmented the Th1 response and decreased Th2 cytokines, granuloma size and fibrosis. Antisera to IFN-gamma, TNF-alpha or IL-12 during IL-12-egg immunization partly restored granuloma size and fibrosis following infection. Variations in the size of granulomas in acute (8 week) infections may be influenced primarily by the number and state of activation of T cells. In chronic (12-16 week) infections immunologic downmodulation proceeded normally in mice without functional CD8+ cells and in IFN-gamma KO mice but not in B cell KO (microMT) mice or in mice deficient in FcR expression in spite of the fact that these mice downregulated their T cell and cytokine responses. It is evident that the participation of cytokines in granuloma formation and regulation is complicated and that the mechanisms controlling both these phenomena are likely to involve both T cells and antibody/FcR interactions.

Pivotal role of TARC, a CC chemokine, in bacteria-induced fulminant hepatic failure in mice

Thymus and activation-regulated chemokine (TARC) is a recently identified lymphocyte-directed CC chemokine which specifically chemoattracts T helper type 2 CD4(+) T cells in human. To establish the pathophysiological roles of TARC in vivo, we investigated whether a monoclonal antibody (mAb) against TARC could inhibit the induction of hepatic lesions in murine model using Propionibacterium acnes and lipopolysaccharide (LPS). P. acnes-induced intrahepatic granuloma formation in the priming phase is essential to the subsequent liver injury elicited by a low dose of LPS. The priming phase appears to be dominated by Th1 type immune responses determined by the profile of chemokine and chemokine receptor expression. TARC was selectively produced by granuloma-forming cells, and CC chemokine receptor 4 (CCR4)-expressing CD4(+) T cells migrated into the liver after LPS administration. In vivo injection of anti-TARC mAb just before LPS administration protected the mice from acute lethal liver damage, which was accompanied by a significant reduction of both CCR4 mRNA expression and IL-4 production by liver-infiltrating CD4(+) T cells. Moreover, both TNF-alpha and Fas ligand expressions in the liver were decreased by anti-TARC treatment. These results suggest that recruitment of IL-4-producing CCR4(+) CD4(+) T cells by granuloma-derived TARC into the liver parenchyma may be a key cause of massive liver injury after systemic LPS administration.

Clotrimazole is an inhibitor of inflammatory angiogenesis and the metabolic activity in sponge granuloma

Clotrimazole (CLT), clinically used as an antifungal drug, inhibited sponge-induced angiogenesis and granulation tissue metabolic activity when administered systemically (120 mg/kg) in rats. We have used functional, biochemical and histological parameters to assess neovascularization and fibrovascular tissue infiltration of the rat sponge granuloma. The sequential development of local blood flow as determined by the outflow rate of sodium fluorescein applied intraimplant, showed that the t1/2 values for the fluorescence peak in the bloodstream decreased in the control group from an initial value of 11 +/- 0.87 min (avascular implants, day 1) to 7.6 +/- 1.5 min at day 7 postimplantation. By contrast t1/2 values in the CLT-treated group remained stable during the 7-day period. The hemoglobin content extracted from the control implants was 2.7 +/- 0.14 microgramsHb/w.w vs. 1.8 +/- 0.18 microgramsHb/w.w in the treated group. The functional and biochemical parameters correlated well with the histological study. Furthermore, the metabolic activity of the sponge-induced granulomas was inhibited by CLT. Because CLT is an inhibitor of signal transduction interfering with the ionic fluxes across the cell membranes, our results suggest that the onset and maintenance of inflammatory angiogenesis induced by subcutaneous implantation of sponge matrix may be regulated by ionic fluxes.

Crohn's disease and sarcoidosis: systemic granulomatosis?

We report an unusual case of severe Crohn's disease with involvement of the lung. In 1993 at age 21 a male patient experienced a Helicobacter-negative duodenitis. A routine chest radiograph revealed spotted opacities in the right upper lobe without discomfort and normal pulmonary function except for a reduced diffusion capacity. Bronchoalveolar lavage showed mild lymphocytosis and biopsies from the macroscopically normal bronchi displayed non-caseating granulomas. In 1995 he had symptoms of peptic ulcer disease with a gastric outlet stenosis. He underwent Billroth I resection with only temporary improvement. Three months later the symptoms had recurred and a stenosing inflammatory process of the duodenum was seen on endoscopy suggesting Crohn's disease. A chest radiograph demonstrated infiltrations in parts of the left lung and bronchoalveolar lavage again revealed alveolar lymphocytosis (CD4/CD8 ratio 3.1). Both the gastrointestinal and pulmonary affections responded to corticosteroids but the duodenal stricture had to be resected. The association of Crohn's disease and pulmonary disorders is discussed.

Haematopoietic capacity of colony-forming cells mobilized in hepatic inflammatory reactions as compared to that of normal bone marrow cells

Chronic inflammatory periovular granulomatous reactions elicited in liver by schistosomal infection are a site of active myelopoiesis. We quantified the colony-forming cells (CFCs) in granulomas and found that the whole liver contains a number of CFCs roughly equivalent to 50% of a femur. Clonogenic analysis showed the presence of committed as well as pluripotent and totipotent CFCs. Long-term Dexter-type cultures showed that the granuloma-derived totipotent CFCs do not have self-renewal capacity. Hence, they did not correspond functionally to haematopoietic stem cells, despite the fact that the stroma established by adherent cells harvested from granulomas had the capacity to sustain long-term proliferation of bone-marrow-derived haematopoietic stem cells. We conclude that myelopoietic cytokines produced by inflammatory reactions in schistosomiasis elicit mobilization of bone marrow CFCs into the circulation, which can settle in hepatic granulomas. This environment may induce their proliferation and differentiation, but not their self-renewal, sustaining temporary production of myeloid cell lineages which nevertheless depends upon cell renewal from the bone marrow pool of haematopoietic precursors.

Circadian rhythm in experimental granulomatous inflammation is modulated by melatonin

Biological rhythms are detected in a variety of physiological and pathological conditions in man and animals, such as rheumatoid arthritis and asthma. Here we describe a circadian rhythm in experimental infectious and non-infectious granuloma. After 30 days of BCG (Bacillus Calmette-Guerin) or nystatin inoculation in the left hind foot of C57B1/6 mice, there is an oscillation with a period of approximately 24 hr in the variation of paw thickness, indicating a circadian rhythm. The acrophase occurred during the light phase, between 9:00 and 13:00 hr, while the nadir occurred in the dark phase, between 21:00 and 01:00 hr. The vascular permeability around the granulomatous lesions was higher at 12:00 hr than at 24:00 hr. This is in agreement with the observation that the thickness of a paw with granulomatous lesion is larger during the light phase. This rhythmic variation was eliminated by either pinealectomy or superior cervical ganglionectomy, which greatly reduce melatonin levels in the blood. Nocturnal replacement of melatonin in pinealectomized mice led to the re-establishment of the circadian rhythm. Thus, the rhythm of the granulomatous lesion is due to the rhythmic melatonin release by the pineal gland. This approach opens new questions regarding the modulation of chronic inflammation in inflammatory diseases that present rhythmic symptoms throughout the day.

Mechanisms accounting for granulomatous responses in hypersensitivity pneumonitis

Hypersensitivity granuloma formation is an immunopathological feature of HP. It is induced by the T cell-mediated delayed-type hypersensitivity reaction to organic dusts or active chemicals invading the lung. Circulating, antigen-reactive, memory CD4+ T cells, generated by previous sensitization, migrate into lung parenchyma in response to chemokines such as RANTES. The T cells develop into either Th0, Th1, or Th2 effector depending upon the conditions in which they first encounter the antigens. The Th1 cells produce IL-2 and IFN-gamma. IFN-gamma can prime macrophages to transcribe and to secrete greater amounts of TNF and IL-1. The macrophages activated by TNF and IL-1 produce a wide range of biologically active mediators such as MAF, MCF, and MIF. These monokines attract young macrophages into the lesions, activate them, and young macrophages develop into mature macrophages, resulting in the hypersensitivity granuloma consisting of epithelioid cells and multinucleated giant cells. CD8+ T cells, the most predominant cell in the lesions of HP, may modulate the granuloma formation via the production of Th1-like or Th2-like cytokines.

Fibrous tissue and angiotensin II

Myofibroblasts (myoFb) are cells responsible for fibrous tissue formation in injured systemic organs such as the heart. Cultured myoFb, obtained from rat cardiac scar tissue, express genes that encode components requisite for angiotensin (Ang) II generation, which in turn regulates myoFb collagen turnover in an autocrine/paracrine manner. In this study, we tested the hypothesis that these wound-healing fibroblast-like cells and locally generated Ang II are involved in other repairing tissue. To test this hypothesis, we used a granuloma pouch model, where a subcutaneous air sac is created followed by injection of croton oil. Pouch tissue was collected at days 4, 7, 14 and 21. The presence of myoFb was determined by immunohistochemical alpha-smooth muscle actin (alpha-SMA) labeling and collagen accumulation by picrosirius red staining. Angiotensin converting enzyme (ACE) and Ang II receptor binding were detected by in vitro quantitative autoradiography using 125I-351A and 125I[Sar1, Ile8]Ang II, respectively, while Ang II receptor subtype was defined by displacement studies using either an AT1 (losartan) or AT2 (PD123177) receptor antagonist. Cells expressing ACE were determined by immunohistochemistry. Ang II content in pouch tissue was measured by radioimmunoassay following HPLC separation while its capacity to generate Ang II was assessed in tissue bath, with and without exogenous Ang I or lisinopril, an ACE inhibitor. Collagen accumulation in pouch tissue was examined by determining hydroxyproline content in response to lisinopril, AT1 or AT2 receptor antagonists (losartan or PD123177). In pouch tissue, we found: (1) myoFb at day 4 which became more extensive at days 7, 14 and 21; (2) morphologic evidence of collagen deposition evident at day 4, which gradually became more extensive thereafter; (3) ACE and Ang II receptor binding was evident at day 4 and remained invariant on days 7, 14 and 21; (4) the predominant Ang II receptor subtype expressed was AT1; (5) myoFb express ACE and AT1 receptors; (6) picogram quantities of Ang II (per g tissue) was evident on days 7, 14 and 21; and (7) Ang II was generated from Ang I substrate. Lisinopril and losartan, but not PD123177, significantly attenuated pouch weight and accumulation of collagen. Thus, in this model of cutaneous repair, the appearance of myoFb is associated with Ang II generation that regulates fibrogenesis by AT1 receptor binding. Signals involved in the appearance of myoFb remain uncertain. Further studies are required to address the regulation of Ang II generation in pouch tissue of the rat.

Nasosinusal fungal granuloma--clinical profile

Fifty cases of nasosinusal fungal granuloma were admitted under the ENT Department in a teaching tertiary care hospital in India during a thirteen-year period. Aspergillus species was found to be the most common causative fungus (29) followed by Mucorales (14), Entomophthorales (5) and Fusarium (2) species. There were 13 cases of non-invasive and 16 cases of invasive variants of Aspergillosis. In spite of intravenous amphotericin B therapy and radical surgical debridement, 81% in the invasive group showed relapse and required prolonged oral antifungal drugs and multiple surgical procedures. Among the 14 cases of Mucormycosis, all of the 10 cases who received intravenous amphotericin B and radical surgery showed complete recovery with no relapse over a period of 2 to 10 years. This is contrary to earlier published reports which suggest poor prognosis. The entomophthoromycosis received oral steroids and cotrimoxazole, and oral potassium iodide or intravenous amphotericin in case of relapse. Both the cases of Fusariosis recovered completely with oral ketoconazole.

Relationship between induction of macrophage chemotactic factors and formation of granulomas caused by mycoloyl glycolipids from Rhodococcus ruber (Nocardia rubra)

Mycoloyl glycolipids cause granulomas in the lungs, liver, and spleen of mice, but the mechanism is not fully understood. To understand the role of macrophage chemotactic factors (MCFs) in granuloma formation, we prepared various mycoloyl glycolipids with different carbohydrate moieties: trehalose dimycolate (TDM), glucose mycolate (GM), mannose mycolate (MM), and fructose mycolate (FM) from Rhodococcus ruber, and examined the relationship between their MCF induction in peritoneal macrophages and the extent of granuloma formation. The molecular mass of each glycolipid was confirmed by fast-atom-bombardment mass-spectrometry. TDM or GM caused granulomas in the lungs, spleen, and liver of ICR mice, but MM and FM did not. The culture supernatant of peritoneal macrophages stimulated with TDM or GM increased macrophage migration, whereas MM and FM had no chemotactic activity. The activity of interleukin-1 (IL-1) in the supernatant was increased equally by each glycolipid and was therefore not related to chemotaxis. Tumor necrosis factor-alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF) were not detected in the four supernatants. The TDM-induced MCF was heat-stable, trypsin-labile, and undialyzable. Furthermore, we separated two MCF active fractions from the supernatant of TDM-stimulated macrophages by gel filtration. These factors acted on macrophages but not on neutrophils. Our results suggested that macrophages recognize the sugar moieties of mycoloyl glycolipids and may, in response, generate a MCF that may play an important role in the macrophage or monocyte recruitment which is essential prior to granuloma formation.

Granulomas in murine schistosomiasis mansoni have a somatostatin immunoregulatory circuit

The role of somatostatin (SRIF) in controlling the granulomatous inflammatory response to infection with the parasite Schistosoma mansoni was explored in mice. The murine granulomas contain SRIF-14. Immunoreactive SRIF and prepro SRIF localize in the cytoplasmic granules of macrophages within the granulomas. The granulomas contain mRNA for prepro SRIF and are not innervated. The production of SRIF by the inflammatory cells appears to be inducible. The granulomas contain mRNA for the SRIF receptors sst2A and sst2B, which are expressed mainly on CD4- T lymphocytes and bind SRIF-14 with high affinity. Antigens from the schistosome eggs stimulate granuloma T lymphocytes to produce cytokines. Interferon-gamma (IFN-gamma) is one such cytokine made by CD4+ T lymphocytes. SRIF-14 suppresses antigen-induced IFN-gamma production from granuloma cells, and this effect is blocked by anti-sst2 antibody. SRIF was shown to inhibit IFN-gamma-induced immunoglobulin G2a (lgG2a) synthesis in murine schistosomiasis. SRIF also blocks substance P (SP)-stimulated IFN-gamma and lgG2a secretion. Schistosome-infected animals treated with the SRIF analog octreotide form smaller granulomas that secrete substantially less IFN-gamma and lgG2a. Unpublished observations suggest that SRIF does not modulate schistosome egg antigen- or concanavalin A-stimulated granuloma lymphocyte proliferation in murine schistosomiasis. In conclusion, SRIF may be an important factor in the control of the granulomatous inflammatory response in murine schistosomiasis.

[Tympanoplasty on only hearing ears]

Tympanoplasty on only hearing ears was performed on 11 patients in Osaka University Hospital and Osaka Rosai Hospital during 1986 1994; this was 0.68% of all cases of middle ear surgery. The patients consisted of 5 with cholesteatoma, 5 with chronic otitis media and 1 with cholesterin granuloma. The mean age was 47.6 years (13-68 years) and the mean follow-up period was 2 years and 7 months (6 months-4 years). Postoperative hearing results was obtained in 9 patients (81.8%) according to the criteria of Otology Japan (1987), and all ears were dry at the final examination. Compared with the preoperative hearing level, postoperative hearing level showed improvement in 3 cases, not in 7 cases (within difference of 5 dB) and deterioration by 10-15 dB in 1 case. Although indications for surgery on only hearing ears are still controversial, we suggest the following: 1) patients with cholesteatoma should be operated on in the ordinary way; 2) patients with chronic otitis media should be operated on only by myringoplasty; 3) all patients must be operated on very carefully by skillful surgeons.

[Cholesterol granuloma of the temporal lobe]

Cholesterol granuloma is a histological term used to describe a non-specific inflammatory reaction produced by the presence of cholesterol crystals, which may originate a foreign-body reaction. Cholesterol granuloma of the temporal bone is silent for years and not preceded by a history of otitis media. The diagnosis is made by CT and MRI, which reveal an expansive, isodense lesion brain tissue and increased signal intensity on both T1 and T2-weighted images respectively. A case of cholesterol granuloma of the petrous apex is presented. The granuloma was excised completely using an infra-retrolabyrinthine approach.