Challenges of smokeless tobacco use in Myanmar.

Myanmar Tobacco Control Law of 2006 covers the control of all forms of tobacco use. After 7-year, tobacco use among adults did not see a decrease. The paper aimed to study the prevalence, details of the products, trade, legislation, tax, marketing, advertising and evidence on morbidity and mortality, and to make recommendations for policy options. Personal communications by authors and colleagues, and searches by keywords in PubMed and on Google, literature review and research from published reports, and various studies and surveys conducted in Myanmar and other countries. Smokeless tobacco use in Myanmar is the highest among ASEAN countries. A variety of SLT products used together with betel chewing poses a challenge; betel quid chewing has been accepted as a cultural norm in both rural and urban areas. Betel quid chewing usually starts at younger ages. Sale, marketing, and advertising of SLT are not under control and thus, road-side kiosks selling betel quid with SLT are mushrooming. Considerable trade of SLT products by illegal and legal means created an increase in access and availability. Low cost of SLT product enables high volume of use, even for the poor families. Taxation for raw tobacco and tobacco products is half the values of the tax for cigarettes. Effective enforcement, amendment of the law, and action for social change are needed.

Smokeless tobacco use in Myanmar.

Smokeless tobacco (SLT) use in various forms is highly prevalent in Myanmar. The aim of this paper is to study the socio-cultural background of SLT use and products of SLT in Myanmar and the prevalence of SLT based on surveys and from other published data bases. Information was obtained from the literature review and through search on PubMed and Google. The use of SLT is deep rooted in Myanmar culture, and there is also wide-spread belief that it is not as dangerous as smoking. SLT use is growing in Myanmar. About 9.8% of the 13-15-year-old school children and 20.8% adults use SLT; it is many-fold higher among men. The use of SLT is prevalent using many different types of tobacco and forms of its use in Myanmar. The socio-cultural acceptance and the myths were compounded by the lack of specific SLT control component in the National Tobacco Control Legislation adopted needs to be addressed as a priority through intensified community awareness programs, public education programs, and advocacy campaigns. Effective enforcement of the law and amendment to include specific components of SLT in the provisions of the law is highly recommended. The prevalence of SLT is high among school children and adults (especially in men) in Myanmar. Betel quid and tobacco is a common form of SLT use. Although control of smoking and consumption of tobacco product law exists, its implementation is weak.

Antifungal activity and pharmacokinetics of posaconazole (SCH 56592) in treatment and prevention of experimental invasive pulmonary aspergillosis: correlation with galactomannan antigenemia.

The antifungal efficacy, safety, and pharmacokinetics of posaconazole (SCH 56592) (POC) were investigated in treatment and prophylaxis of primary pulmonary aspergillosis due to Aspergillus fumigatus in persistently neutropenic rabbits. Antifungal therapy consisted of POC at 2, 6, and 20 mg/kg of body weight per os; itraconazole (ITC) at 2, 6, and 20 mg/kg per os; or amphotericin B (AMB) at 1 mg/kg intravenously. Rabbits treated with POC showed a significant improvement in survival and significant reductions in pulmonary infarct scores, total lung weights, numbers of pulmonary CFU per gram, numbers of computerized-tomography-monitored pulmonary lesions, and levels of galactomannan antigenemia. AMB and POC had comparable therapeutic efficacies by all parameters. By comparison, animals treated with ITC had no significant changes in outcome variables in comparison to those of untreated controls (UC). Rabbits receiving prophylactic POC at all dosages showed a significant reduction in infarct scores, total lung weights, and organism clearance from lung tissue in comparison to results for UC (P < 0.01). There was dosage-dependent microbiological clearance of A. fumigatus from lung tissue in response to POC. Serum creatinine levels were greater (P < 0.01) in AMB-treated animals than in UC and POC- or ITC-treated rabbits. There was no elevation of serum hepatic transaminase levels in POC- or ITC-treated rabbits. The pharmacokinetics of POC and ITC in plasma demonstrated dose dependency after multiple dosing. The 2-, 6-, and 20-mg/kg dosages of POC maintained plasma drug levels above the MICs for the entire 24-h dosing interval. In summary, POC at > or =6 mg/kg/day per os generated sustained concentrations in plasma of > or =1 microg/ml that were as effective in the treatment and prevention of invasive pulmonary aspergillosis as AMB at 1 mg/kg/day and more effective than cyclodextrin ITC at > or =6 mg/kg/day per os in persistently neutropenic rabbits.

Dosage-dependent antifungal efficacy of V-echinocandin (LY303366) against experimental fluconazole-resistant oropharyngeal and esophageal candidiasis.

V-echinocandin (VER-002; LY303366) is a semisynthetic derivative of echinocandin B and a potent inhibitor of fungal (1, 3)-beta-D-glucan synthase. We studied the antifungal efficacy, the concentrations in saliva and tissue, and the safety of VER-002 at escalating dosages against experimental oropharyngeal and esophageal candidiasis caused by fluconazole-resistant Candida albicans in immunocompromised rabbits. Study groups consisted of untreated controls, animals treated with VER-002 at 1, 2.5, and 5 mg/kg of body weight/day intravenously (i.v.), animals treated with fluconazole at 2 mg/kg/day i.v., or animals treated with amphotericin B at 0.3 mg/kg/day. VER-002-treated animals showed a significant dosage-dependent clearance of C. albicans from the tongue, oropharynx, esophagus, stomach, and duodenum in comparison to that for untreated controls. VER-002 also was superior to amphotericin B and fluconazole in clearing the organism from all sites studied. These in vivo findings are consistent with the results of in vitro time-kill assays, which demonstrated that VER-002 has concentration-dependent fungicidal activity. Esophageal tissue VER-002 concentrations were dosage proportional and exceeded the MIC at all dosages. Echinocandin concentrations in saliva were greater than or equal to the MICs at all dosages. There was no elevation of serum hepatic transaminase, alkaline phosphatase, bilirubin, potassium, or creatinine levels in VER-002-treated rabbits. In summary, the echinocandin VER-002 was well tolerated, penetrated the esophagus and salivary glands, and demonstrated dosage-dependent antifungal activity against fluconazole-resistant esophageal candidiasis in immunocompromised rabbits.

A role for FAK in the Concanavalin A-dependent secretion of matrix metalloproteinase-2 and -9.

To study the signaling pathway critical for the secretion of matrix metalloproteinases (MMPs), we examined the role of focal adhesion kinase (FAK) in Concanavalin A (Con A)-stimulated cells. We established a cell line in which FAK gene was conditionally inducible by use of FAK-null fibroblasts and the tetracycline repression system. In this cell line, FAK expression was undetectable in the presence of tetracycline but induced within 1 day by the removal of the drug. We found that FAK expression augmented the Con A-dependent secretion of MMP-9 and MMP-2. In contrast, proteolytic activation of MMP-2 by Con A-treatment did not require FAK expression. In addition, activation of MMP-secretion and tyrosine phosphorylation of FAK by Con A, but not the proteolytic activation of MMP-2, required attachment of the cells to the extracellular matrix. Taken together, our results suggest that the FAK signaling pathway play a pivotal role in the secretion of MMPs.

Dose-dependent pharmacokinetics of amphotericin B lipid complex in rabbits.

Amphotericin B lipid complex (ABLC) was recently approved by the Food and Drug Administration for treatment of patients with invasive fungal infections who are intolerant of or refractory to conventional amphotericin B therapy. Little is known, however, about the pharmacokinetics of this new antifungal compound. We therefore investigated the pharmacokinetics of ABLC in comparison with those of conventional desoxycholate amphotericin B (DAmB) in rabbits. The pharmacokinetics of DAmB in a rabbit model were similar to those previously reported in humans. The pharmacokinetics of ABLC differed substantially from those of DAmB. Plasma amphotericin B levels following ABLC administration were 10 times lower than those following administration of an equal dosage of DAmB. The levels of ABLC in whole blood were approximately 40 times greater than those in plasma. The ABLC model differed from the DAmB model by (i) a dose- and time-dependent uptake and return between the plasma compartment and apparent cellular components of the blood-sediment compartment and (ii) time-dependent tissue uptake and return to plasma from serially connected compartments. Following infusion of ABLC, there was a nonlinear uptake into the apparent cellular components of the blood-sediment compartment. This uptake was related to the reciprocal of the integral of the total amount of drug infused (i.e., the more drug infused the greater the fractional uptake between 0.5 and 5 mg/kg of body weight for ABLC). The transfer of drug from plasma to the cellular components of the blood-sediment compartment resulted in initial uptake followed by rapid redistribution back to the plasma. The study describes a detailed model of the pharmacokinetics of ABLC and characterizes a potential role of the cellular components of the blood-sediment compartment in the distribution of this new antifungal compound in tissue.

Antifungal activity of splenic, liver and pulmonary macrophages against Candida albicans and effects of macrophage colony-stimulating factor.

Disseminated infections due to Candida albicans are frequently encountered in immunocompromised patients. We compared the antifungal activities of macrophages residing in spleen, liver and lungs of rabbits against blastoconidia and pseudohyphae of C. albicans. Splenic adherent cells (SAC), Kupffer cells (KC) and pulmonary alveolar macrophages (PAM) all ingested blastoconidia efficiently. SAC caused significantly more damage to unopsonized pseudohyphae compared with KC (P < 0.01) or PAM (P < 0.001). Incubation of SAC with 15 ng ml(-1) of recombinant human macrophage colony-stimulating factor (M-CSF) at 37 degrees C for 2 days significantly enhanced phagocytosis (P = 0.02) and killing (P = 0.05) of blastoconidia. In contrast, M-CSF had no effect on phagocytic activities of KC or PAM against blastoconidia or on damage caused by any of the macrophages to pseudohyphae of C. albicans. Thus, although all three resident macrophage types ingest blastoconidia efficiently, they differ in their capacity to cause damage to pseudohyphae and in their responsiveness to M-CSF for antifungal activation. M-CSF augments the capacity of SAC to ingest and kill blastoconidia and may therefore have a role in the treatment and prevention of hematogenously disseminated candidiasis.

Fibronectin activates matrix metalloproteinase-9 secretion via the MEK1-MAPK and the PI3K-Akt pathways in ovarian cancer cells.

Cell adhesion to the extracellular matrix appears to trigger a cascade of intracellular signalings. We have previously shown that treatment of ovarian cancer cells, NOM1, with fibronectin (FN) stimulated matrix metalloproteinase (MMP)-9 secretion and thereby activated the invasiveness of cells via the FAK/Ras signaling pathway. By use of chemical inhibitors, we investigated the downstream effectors critical for FN-dependent secretion of MMP-9. Treatment of cells with MEK1 inhibitors, U0126 and PD98059, dramatically suppressed the secretion of MMP-9 activated by FN. Similarly, P1-3 kinase inhibitors, Wortmannin and LY294002, strongly suppressed the FN-dependent secretion of MMP-9 together with the inhibition of Akt activation. In contrast, a specific PKC inhibitor (GF109203X) showed no inhibitory effect on the FN-dependent MMP-9 secretion. Moreover, we found that both the MEK1 inhibitor and the P13-K inhibitor, but not the PKC inhibitor, strongly suppressed the invasiveness of NOM1 cells. Taken together, our results suggest that activation of dual signaling pathways, MEKI-MAPK and P13K-Akt, is required for the FN-dependent activation of MMP-9 secretion. Our results suggest the importance of these signaling molecules as a chemotherapeutic target for cancer.

Ras pathway is required for the activation of MMP-2 secretion and for the invasion of src-transformed 3Y1.

To search for the signaling pathway critical for tumor invasion, we examined the effects of dominant negative ras (S17N ras) expression on the activation of matrix metalloproteinase-2 (MMP-2) in src-transformed 3Y1, SR3Y1, under the control of conditionally inducible promoter. In SR3Y1 clones transfected with S17N ras, augmented secretion and proteolytic activation of MMP-2 were dramatically suppressed by S17N Ras expression, while tyrosine phosphorylation of cellular proteins was not suppressed. We found that invasiveness of SR3Y1 cells assayed by the modified Boyden Chamber method was strongly suppressed by S17N Ras expression. In contrast, cell morphology reverted partially and glucose uptake remained unchanged by S17N Ras expression. In addition, treatment of SR3Y1 with manumycin A, a potent inhibitor of Ras farnesyltransferase, strongly suppressed both augmented secretion and proteolytic activation of MMP-2. Contrary, treatment of SR3Y1 with wortmannin or TPA showed no clear effect on MMP-2 activation. Thus, these results strongly suggest that Ras-signaling, but neither P13 kinase- nor protein kinase C-signalings, plays a critical role in activation of MMP-2 and, subsequently, in the invasiveness of src-transformed cells.

Antifungal activity of LY303366, a novel echinocandin B, in experimental disseminated candidiasis in rabbits.

The safety and antifungal activity of LY303366 (LY), a new broad-spectrum semisynthetic echinocandin, were studied against disseminated candidiasis in persistently neutropenic rabbits. In vitro time-kill assays demonstrated that LY has concentration-dependent fungicidal activity. The pharmacokinetics of LY in the plasma of nonneutropenic rabbits suggested a linear relationship between dose and area under the curve (AUC). The times spent above the MIC during the experimental dosing interval of 24 h were 4 h for LY at 0.1 mg/kg of body weight/day (LY0.1), 8 h for LY at 0.25 mg/kg/day (LY0.25), 12 h for LY at 0.5 mg/kg/day (LY0.5), and 20 h for LY at 1 mg/kg/day (LY1). Antifungal therapy was administered to infected rabbits for 10 days starting 24 h after the intravenous (i.v.) inoculation of 10(3) Candida albicans blastoconidia. Study groups consisted of untreated controls (UCs) and animals treated with amphotericin B (AmB; 1 mg/kg/day i.v.), fluconazole (FLU; 10 mg/kg/day i.v.), and LY0.1, LY0.25, LY0.5, or LY1 i.v. Rabbits treated with LY0.5, LY1, AmB, and FLU had similarly significant clearance of C. albicans from the liver, spleen, kidney, lung, vena cava, and brain in comparison to that for UCs. There was a dose-dependent clearance of C. albicans from tissues in response to LY. Among rabbits treated with LY0.1 there was a significant reduction of C. albicans only in the spleen. In animals treated with LY0.25 there was a significant reduction in all tissues but the brain. By comparison, LY0.5 and LY1 cleared all tissues, including the brain, of C. albicans. These in vivo findings were consistent with the results of in vitro time-kill assays. A dose-dependent effect of altered cell wall morphology was observed among UCs and animals treated with LY0.1, and LY0.25, with a progressive transition from hyphal structure to disrupted yeast forms. Serum creatinine levels were higher and serum potassium levels were lower in AmB-treated rabbits than in UCs and LY- and FLU-treated rabbits. LY0.5 and LY1 were well tolerated, displayed predictable pharmacokinetics in plasma, and had activities comparable to those of AmB and FLU in the treatment of disseminated candidiasis in persistently neutropenic rabbits.

Interleukin-12 enhances antifungal activity of human mononuclear phagocytes against Aspergillus fumigatus: implications for a gamma interferon-independent pathway.

The potential of recombinant human interleukin-12 (IL-12) to enhance the capacity of human monocytes (MNC) to elicit an oxidative burst and damage hyphae of Aspergillus fumigatus was investigated. Incubation of peripheral blood mononuclear cells (PBMC) from healthy adults with 10 to 100 ng of IL-12/ml at 37 degrees C for 2 to 3 days enhanced the production of superoxide anion (O2-) in response to phorbol myristate acetate (PMA) (P = 0.04) and unopsonized A. fumigatus hyphae (P = 0.03) and further enhanced hyphal damage (P = 0.009). Anti-gamma interferon (anti-IFN-gamma) blocked secretion of IFN-gamma by IL-12-treated PBMC but did not inhibit IL-12-induced O2- production by these cells in response to PMA. In addition, IL-12-treated elutriated MNC secreted no IFN-gamma or tumor necrosis factor alpha but exhibited enhanced O2- production compared to controls (P = 0.013). These findings demonstrate that IL-12 augments oxidative antifungal activities of MNC via an IFN-gamma-independent route, suggesting a novel pathway of IL-12 action in antifungal defense.

Tumor necrosis factor alpha enhances antifungal activities of polymorphonuclear and mononuclear phagocytes against Aspergillus fumigatus.

Invasive aspergillosis is a serious complication in immunocompromised patients. The effects of recombinant human tumor necrosis factor alpha (TNF-alpha) on antifungal activities of human neutrophils (polymorphonuclear leukocytes [PMNs]), human monocytes (MNCs), and rabbit pulmonary alveolar macrophages (PAMs) against Aspergillus fumigatus were studied. The percentage of PMN-induced hyphal damage was increased after 30 min of incubation of PMNs with 0.1 ng of TNF-alpha per ml at 37 degreesC (P = 0.043). At 0.1 to 10 ng/ml, TNF-alpha also increased superoxide anion (O2-) produced by PMNs in response to phorbol myristate acetate, N-formylmethionyl leucyl phenylalanine, and unopsonized hyphae (P < 0.01) but did not exert any effect on PMN phagocytosis of conidia in the presence of serum. By comparison, TNF-alpha induced only a slight increase in O2- production by MNCs in response to phorbol myristate acetate (P = 0.05) and no concomitant increase in the percentage of MNC-induced hyphal damage. Incubation of MNCs with TNF-alpha at 0.001 to 10 ng/ml for 2 days had no effect on phagocytosis or conidiocidal activity. By contrast, incubation of PAMs with TNF-alpha at 0.1 to 10 ng/ml for 2 days increased phagocytosis of conidia (P = 0.03). Thus, TNF-alpha augments the capacity of PMNs to damage Aspergillus hyphae, possibly through enhanced oxidative mechanisms, and increases PAM phagocytic activity against conidia. As such, TNF-alpha may have an important role in host defense against aspergillosis, and neutralization of its activity may be complicated by increased susceptibility to aspergillosis.

Antifungal efficacy, safety, and single-dose pharmacokinetics of LY303366, a novel echinocandin B, in experimental pulmonary aspergillosis in persistently neutropenic rabbits.

LY303366 is a novel semisynthetic derivative of echinocandin B and a potent inhibitor of fungal (1,3)-beta-D-glucan synthase. The antifungal efficacy and safety of LY303366 were investigated in treatment and prophylaxis of primary pulmonary aspergillosis due to Aspergillus fumigatus in persistently neutropenic rabbits. Treatment study groups were either not treated (controls) or treated with amphotericin B (AmB) at 1 mg/kg of body weight per day or with LY303366 at 1, 5, 10, and 20 mg/kg/day. In rabbits treated with LY303366, there was a significant improvement in survival and a reduction in organism-mediated pulmonary injury measured by the number of infarcts, total lung weight, and ultrafast computerized tomography scan pulmonary lesion score. Rabbits receiving prophylactic LY303366 also demonstrated significant improvement in survival and reduction in organism-mediated pulmonary injury. AmB and LY303366 had comparable therapeutic efficacies by all parameters with the exception of reduction in tissue burden of A. fumigatus, where AmB was superior to LY303366. LY303366 demonstrated a dose-dependent effect on hyphal injury with progressive truncation, swelling, and vacuolization. LY303366 administered in single doses of 1, 5, 10, and 20 mg/kg demonstrated dose-proportional increases in the maximum concentration of drug in plasma and the area under the concentration-time curve from 0 to 72 h with no changes in plasma drug clearance. The 1-mg/kg dosage maintained plasma drug levels above the MIC for 18 h, and dosages of >/=5 mg/kg maintained plasma drug levels above the MIC for the entire 24-h dosing interval. There was no significant elevation of the concentrations of hepatic transaminases or creatinine in serum in LY303366-treated rabbits. In summary, LY303366 improved survival and decreased pulmonary injury with no apparent toxicity in the treatment and prevention of invasive pulmonary aspergillosis in persistently neutropenic rabbits.

Compartmental pharmacokinetics and tissue drug distribution of the pradimicin derivative BMS 181184 in rabbits.

The pharmacokinetics of the antifungal pradimicin derivative BMS 181184 in plasma of normal, catheterized rabbits were characterized after single and multiple daily intravenous administrations of dosages of 10, 25, 50, or 150 mg/kg of body weight, and drug levels in tissues were assessed after multiple dosing. Concentrations of BMS 181184 were determined by a validated high-performance liquid chromatography method, and plasma data were modeled into a two-compartment open model. Across the investigated dosage range, BMS 181184 demonstrated nonlinear, dose-dependent kinetics with enhanced clearance, reciprocal shortening of elimination half-life, and an apparently expanding volume of distribution with increasing dosage. After single-dose administration, the mean peak plasma BMS 181184 concentration (Cmax) ranged from 120 microg/ml at 10 mg/kg to 648 microg/ml at 150 mg/kg; the area under the concentration-time curve from 0 to 24 h (AUC0-24) ranged from 726 to 2,130 microg . h/ml, the volume of distribution ranged from 0.397 to 0.799 liter/kg, and the terminal half-life ranged from 4.99 to 2.31 h, respectively (P < 0.005 to P < 0.001). No drug accumulation in plasma occurred after multiple daily dosing at 10, 25, or 50 mg/kg over 15 days, although mean elimination half-lives were slightly longer. Multiple daily dosing at 150 mg/kg was associated with enhanced total clearance and a significant decrease in AUC0-24 below the values obtained at 50 mg/kg (P < 0.01) and after single-dose administration of the same dosage (P < 0.05). Assessment of tissue BMS 181184 concentrations after multiple dosing over 16 days revealed substantial uptake in the lungs, liver, and spleen and, most notably, dose-dependent accumulation of the drug within the kidneys. These findings are indicative of dose- and time-dependent elimination of BMS 181184 from plasma and renal accumulation of the compound after multiple dosing.

Antifungal activity of the pradimicin derivative BMS 181184 in the treatment of experimental pulmonary aspergillosis in persistently neutropenic rabbits.

The activity of the pradimicin derivative BMS 181184 was evaluated in a model of invasive pulmonary aspergillosis in persistently neutropenic rabbits and compared with that of amphotericin B deoxycholate. BMS 181184 at total daily doses of 50 and 150 mg/kg of body weight was at least as effective as amphotericin B at 1 mg/kg once a day in conferring survival and had comparable activity in reducing organism-mediated tissue injury and excess lung weight. Although treatment at all dosing regimens of BMS 181184 resulted in significant reductions in fungal tissue burden compared to untreated controls, equivalence to amphotericin B occurred only at the higher dosage level. Similar observations were made in bronchoalveolar lavage fluid cultures obtained postmortem. Monitoring of the animals through ultrafast computerized tomography scan revealed a marked resolution of pulmonary lesions during treatment with BMS 181184. The compound was well tolerated at all dosing regimens, and no toxicity was noted. Pharmacokinetic studies revealed nonlinear drug disposition with increased clearance at higher dosages and some evidence for extravascular drug accumulation. BMS 181184 had excellent activity in the treatment of experimental invasive pulmonary aspergillosis in persistently neutropenic rabbits, thus underscoring the potential of pradimicin derivatives in therapy of invasive aspergillosis in the neutropenic host.

Increased serum concentrations of interleukin-10 in patients with hepatosplenic candidiasis.

Hepatosplenic candidiasis (HSC) becomes clinically overt in cancer patients upon recovery from neutropenia. HSC may be a consequence of a Th1-Th2 imbalance, characterized by increased serum levels of one or more cytokines. Serum levels of two immunosuppressive cytokines, markers of the Th2 pathway, interleukin (IL)-4 and IL-10 were measured by ELISA in 10 patients with HSC (22 samples) and compared with 19 healthy blood donors, 13 patients with cancer but no infection (23 samples), and 11 patients with cancer and various bacterial infections (17 samples). IL-4 was undetectable in all controls and patients. By contrast, levels of IL-10 were increased in HSC patients compared with levels in healthy donors and cancer patients without infection (P < .001) or with bacterial infections (P < .01). These findings indicate that IL-10 but not IL-4 is increased in patients with HSC and suggest that IL-10 plays a role in the pathogenesis of this infection.

IL-10 exerts suppressive and enhancing effects on antifungal activity of mononuclear phagocytes against Aspergillus fumigatus.

Invasive aspergillosis has emerged as a frequent and serious infection in immunocompromised patients. We studied the effects of human IL-10 on antifungal activity of monocytes (MNCs) from healthy adults against Aspergillus fumigatus after incubation with IL-10 at 37 degrees C for 2 to 4 days. IL-10 (2-20 ng/ml)-pretreated MNCs exhibited approximately 40% suppression of superoxide anion (02-) production in response to PMA and FMLP (p < or = 0.003), and anti-IL-10 containing supernatant neutralized the IL-10 effect. IL-10 (20 ng/ml)-pretreated MNCs exhibited decreased damage of Aspergillus hyphae after 2 to 4 days (55-98% decrease, p < or = 0.04). The MNC phagocytic activity against conidia, as assessed by microscopy (percentage of phagocytosing MNCs and number of intracellular conidia per MNC) as well as by colony counting (colonies grown from intracellular conidia), was enhanced by 127% (p = 0.006), 14% (p = 0.03), and 23% (p = 0.009), respectively. MNC capacity to inhibit intracellular germination was marginally enhanced (p = 0.04) and intracellular conidiocidal activity was unaffected by IL-10. IL-4 (5 ng/ml) did not change the up-regulatory IL-10 effect on phagocytosis. IFN-gamma (25 ng/ml) and granulocyte-macrophage CSF (20 ng/ml), but not macrophage CSF (15 ng/ml), appeared to counteract suppressive IL-10 effects. Thus, IL-10 suppresses oxidative burst and antifungal activity of MNCs against Aspergillus hyphae, while increasing their phagocytic activity. These findings further elucidate a potential role of IL-10 in the pathogenesis of invasive aspergillosis, which may lead to new treatment strategies.

Transfer of a gene encoding the anticandidal protein histatin 3 to salivary glands.

Mucosal candidiasis, the most common opportunistic fungal infection in human immunodeficiency virus (HIV)-infected patients, is an early sign of clinically overt acquired immunodeficiency syndrome (AIDS) and an important cause of morbidity, particularly in HIV-infected children. The appearance of azole-resistant strains of Candida albicans had made clinical management of candidiasis increasingly difficult. We propose a novel approach to the management of candidal infections that involves the use of naturally occurring antifungal proteins, such as the histatins. Histatins are a family of small proteins that are secreted in human saliva. We have constructed recombinant adenovirus vectors that contain the histatin 3 cDNA. These vectors are capable of directing the expression of histatin 3 in the saliva of rats at up to 1,045 micrograms/ml, well above the levels found in normal human saliva. The adenovirus-directed histatin demonstrated a 90% candidacidal effect in the timed-kill assay against both fluconazole-susceptible and fluconazole-resistant strains of C. albicans and inhibited germination by 45% in the same strains. These studies suggest that a gene transfer approach to overexpress naturally occurring antifungal proteins may be useful in the management of mucosal candidiasis.

Effects of macrophage colony-stimulating factor on antifungal activity of mononuclear phagocytes against Aspergillus fumigatus.

The effects of recombinant human macrophage colony-stimulating factor (M-CSF) on antifungal activity of human monocytes (MNC), MNC-derived macrophages (MDM), and rabbit pulmonary alveolar macrophages (PAM) against Aspergillus fumigatus were studied. MNC-induced hyphal damage was augmented by incubation with M-CSF (P = .027); PAM-induced hyphal damage was moderately enhanced by M-CSF (P = .046). Phagocytosis of Aspergillus conidia by MDM and PAM was strongly enhanced by M-CSF (P < .01). MNC pretreated with M-CSF exhibited enhanced superoxide anion production in response to PMA (P = .026). This effect was not associated with increased levels of mRNA transcripts of the components of NADPH oxidase, the enzyme responsible for superoxide anion production. M-CSF augments antifungal activity of mononuclear phagocytes against both conidia and hyphae of Aspergillus fumigatus partly by enhancement of oxidation-dependent mechanisms and may have an important immunomodulatory role in prevention and treatment of invasive aspergillosis in leukopenic patients.