Toll-like receptor-mediated activation of B cells and macrophages by polysaccharide isolated from cell culture of Acanthopanax senticosus

We investigated the mechanism of the immunomodulatory action of polysaccharide (ASP) isolated from a cell culture of Acanthopanax senticosus. ASP was found to directly increase the proliferation and differentiation of B cells, and the cytokine production of macrophage, but not the proliferation and cytokine production of T cells. Since ASP cannot penetrate the cell membrane due to its large molecular mass, such cellular activation may be caused by the surface binding of ASP to receptors expressed on B cells and macrophages. The possibility that TLRs, which are known to be involved in immune-related responses, may be the receptor(s) of ASP was investigated. The immunomodulating activities of ASP on the B cells and macrophages of C3H/HeJ mice, expressing a defective toll-like receptor (TLR)-4, were decreased versus the corresponding cells from C3H/HeN mice. In addition, the activities of ASP on B cells and macrophages were significantly reduced by treating the cells with antibodies to TLR4 and TLR2 prior to ASP, suggesting that both of them are the possible receptors of ASP. The ligation of TLRs induced by ASP was able to activate mitogen-activated protein kinases (MAPKs), such as Erk1/2, p38 and JNK, and the transcription factor NF-kappaB. Although ASP was shown to activate the TLR signaling cascades in the same manner as lipopolysaccharide (LPS), these two could be differentiated by the finding that polymyxin B (PMB), a specific inhibitor of LPS, did not significantly affect the activities of ASP on B cells and macrophages. Taken together, our results demonstrate that ASP, isolated from a cell culture of A. senticosus, activates B cells and macrophages by interacting with TLRs and leading to the subsequent activation of mitogen-activated protein kinases and NF-kappaB.

Effect of modified atmosphere packaging and irradiation in combination on content of nitrosamines in cooked pork sausage

The effect of modified atmosphere packaging and irradiation in combination on nitrosodimethylamine (NDMA) and nitrosopyrrolidine (NPYR) levels in pork sausage was studied. Emulsion-type cooked pork sausage was manufactured and packaged in aerobic, CO2 (100%), N2 (100%), and CO2/N2 (25%/75%) environments, respectively, and irradiated at 0, 5, 10, and 20 kGy with gamma irradiation. The nitrosamine contents were significantly reduced by irradiation, and the reduction of nitrosamines was more extensive with modified atmosphere packaging than with aerobic packaging. The correlation coefficient between irradiation dose and nitrosamine content indicated that irradiation can reduce the levels of nitrosamines. The combination of irradiation and modified atmosphere packaging is effective in enhancing the chemical safety of sausage by reducing nitrosamines, if present, as well as enhancing the microbial safety of cooked pork sausage.

Characterization of B cell membrane receptors of polysaccharide isolated from the root of Acanthopanax koreanum

We investigated the immunomodulatory activity of polysaccharide isolated from the root of Acanthopanax koreanum (AK) at the cellular level. AK directly increased B cell proliferation and antibody production, but did not affect the expression of IL-2, IFN-gamma or IL-4 by T cells, or T cell proliferation in vitro. Since AK cannot penetrate cells due to its large molecular mass, B cell activation may be caused by the surface binding of AK to B cell-specific receptors. The role of TLR4 as an AK receptor was shown by the fact that AK activity in B cells from C3H/HeJ mice, which are known to have a defective Toll-like receptor (TLR)-4, was found to be reduced compared with that in control cells from C3H/HeN mice. AK activity was also reduced by antibodies blocking TLR2, TLR4, CD19 or CD79b, but not by an antibody blocking CD38, which suggests AK receptor profiling in B cells. Two main differences between AK and lipopolysaccharide (LPS) were observed. First, LPS activity was inhibited by antibodies to either TLR2 or TLR4, but not by antibodies to CD19, CD79b or CD38. Another was that LPS-induced B cell proliferation was inhibited by polymyxin B (PMB), a specific inhibitor of LPS, whereas AK activity was not affected. Taken together, our results demonstrate that AK directly activates B cells, but not T cells, and suggest that AK has a broader receptor profile than LPS in B cells.

Modulation of natural killer cell activity affected by electroacupuncture through lateral hypothalamic area in rats

Electroacupuncture (EA) has been reported to modulate natural killer cell (NK cell) activities. Also it is well known that hypothalamus directly mediates the effects of EA on analgesia. Especially lateral hypothalamic area (LHA) is related to splenic NK cell activities. In order to investigate the relationship between hypothalamus and effects of EA on NK cell activity, lesions have been made bilaterally at LHA of Spraque-Dawley rats. Subsequently, NK cell cytotoxities of normal and lesioned rats were measured with (51)Cr release immunoassay after EA stimulation for 2 and 14 days. NK cell activity of EA group was significantly higher than sham group. In addition, lesions abolished effects of EA on NK cell activity. These results strongly suggest that LHA is closely related to increase of NK cell activity induced by EA.

Pharmacological preconditioning with low-dose cyclosporine or FK506 reduces subsequent ischemia/reperfusion injury in rat kidney

BACKGROUND

Ischemia/reperfusion (I/R) injury in the early posttransplant period is closely associated with delayed recovery of graft function, increased acute rejection, and late allograft dysfunction. Pharmacological preconditioning with low-dose cyclosporine (CsA) or FK506 was performed to induce ischemic tolerance in rat kidney with I/R injury.

METHODS

Low-dose CsA (3 mg/kg, administered i.v.) or FK506 (0.3 mg/kg i.v.) were used to induce ischemic tolerance in Sprague-Dawley rats, and the induction of heat shock protein (hsp) 70 by CsA or FK506 was evaluated overtime. Rats were pretreated with CsA or FK506 6 hr before I/R injury when hsp70 was maximally expressed, and were killed 24 hr later. The effect of pharmacological preconditioning on subsequent I/R injury was evaluated in terms of renal function, histopathology score, assays for apoptosis (DNA fragmentation analysis, TUNEL staining, expressions of pro-apoptotic genes, and caspase activity), and the expression of inflammatory cytokine genes (interleukin-1 and tumor necrosis factor-alpha).

RESULTS

Preconditioning with low-dose CsA or FK506 significantly improved renal function and renal histology, compared to rats with I/R injury. Apoptotic cell death (typical DNA laddering and increased TUNEL-positive cells) in rat kidneys with I/R injury, was decreased by pretreatment with low-dose CsA or FK506. Increased expression of pro-apoptotic genes (Fas, Fas-ligand, caspase 1 and 3) and activated caspases in ischemic rat kidneys were decreased after CsA or FK506 pretreatment.

CONCLUSIONS

Pretreatment with low-dose CsA or FK506 prevents subsequent I/R injury, and this effect may be related to the induction of hsp70. Pretreatment of renal donors with low-dose CsA or FK506 may result in an improvement in immediate posttransplant function.

Epidemiologic and clinical survey of Behcet's disease in Korea: the first multicenter study

The prevalence of Behcet's disease is the highest in the East Asian and the Mediterranean countries. Behcet's disease is also distributed in the Asian countries, but the nationwide survey has not been performed in Korea yet. The Korean Study Group for Behcet's Disease, founded in 1999, conducted a multicenter, retrospective survey on epidemiologic and clinical features of the patients with Behcet's disease from 20 hospitals around the nation from 1997 to 1999. Of 3,497 patients, 1,527 were classified into complete or incomplete type of Behcet's disease according to the revised Shimizu's classification. The sex ratio was 1:1.75 with the female predominance. Geographical distribution showed the highest frequency in Seoul (38.5%). Clinically, 98.8% had oral ulcers, 83.2% had genital ulcers, 84.3% had skin lesions and 50.9% had ocular lesions. As for the minor clinical manifestations, articular symptoms were the most frequent. The pathergy test showed positive in 15.4% of patients and revealed a higher positive rate in males (20.2%) than in females (12.7%). In conclusion, we performed the first multicenter study on Behcet's disease in Korea and revealed the female predominance, higher frequency of ocular lesions, and lower positivity of pathergy test in the patients.

Protease activity and host cell binding of the 42-kDa rhoptry protein from Toxoplasma gondii after secretion

Three proteases were identified in the excretory/secretory proteins (ESP) from Toxoplasma gondii by the gelatin acrylamide gel electrophoresis (GAGE), of which the molecular masses were 80, 70, and 42 kDa. One of the proteases with 42 kDa was reactive to a monoclonal antibody (mAb), Tg786 clone, which was localized in the rhoptry of T. gondii by immunohistochemistry. The protease was maximally active at the pH range between 7.5 and 8.5, and was sensitive to inhibition by TPCK and EGTA. The gelatinolytic activity of the protease was dependent on the concentration of calcium ion. The protease was active only in the millimolar ranges of calcium but not in micromolar ranges, implicating that the secretion is critical event for the activation of the protease. The secreted protease was shown to bind to the host cells upon Western blot and immunofluorescence analysis. It is suggested that the protease may target to the plasma membrane of the host cells, which provides appropriate environment for the entry of the parasite into host cells. The mAb (Tg786) of T. gondii also reacted with a protein of the same size and equivalent locality of rhoptry in Neospora caninum, a similar Apicomplexan protozoa, suggesting that secreted protease mediates a common function in the mechanism of entry into host cells.

Preconditioning with sodium arsenite inhibits apoptotic cell death in rat kidney with ischemia/reperfusion or cyclosporine-induced Injuries. The possible role of heat-shock protein 70 as a mediator of ischemic tolerance

This study was performed to evaluate the effect of heat-shock protein (HSP)70 induction with sodium arsenite (SA) on ischemia/reperfusion (I/R) or cyclosporin A (CsA)-induced injuries in rat kidney. Rats were classified into five groups (sham, I/R, SA+I/R, I/R+CsA and SA+I/R+CsA groups) according to both the status of SA pretreatment and treatment with CsA. SA (6 mg/kg, i.v.) pretreatment was accomplished 12 h before I/R injury, and CsA (20 mg/kg, s.c.) was given subsequent to I/R injury. The effect of SA pretreatment on I/R injury was evaluated using measurements of renal function, the histopathology score, and assays for apoptosis (DNA fragmentation analysis, TUNEL staining, mRNA expressions of the pro-apoptotic genes and caspase activities). In addition, mitochondrial morphology was examined by electron microscopy. Induction of HSP70 with SA improved both renal function and the histopathology score as compared to the group without HSP70 induction. The assays for apoptosis revealed that SA pretreatment decreased the DNA laddering pattern, TUNEL-positive cells, mRNAs expression of pro-apoptotic genes and caspase activities as compared with the group without SA pretreatment. In addition, the mitochondrial morphology was well preserved in the groups with SA pretreatment. In conclusion, SA pretreatment prevents subsequent I/R or CsA-induced injuries in the rat kidney, and this renoprotective effect appears to be mediated by induction of HSP70.

Influence of the renin-angiotensin system on epidermal growth factor expression in normal and cyclosporine-treated rat kidney

BACKGROUND

Epidermal growth factor (EGF) plays an important role in renal tubular regeneration after ischemic injury in kidney. The present study reports the association between the renin-angiotensin system (RAS) and EGF, and the effect of angiotensin II blockade with losartan (LSRT) on EGF expression in an experimental model of chronic cyclosporine (CsA) nephrotoxicity in rats.

METHODS

Two separate experiments were performed. In the first experiment, rats on the normal-salt diet (NSD; 0.3%) or low-salt diet (LSD; 0.05%) were treated with or without LSRT for four weeks. In the second experiment, rats on the NSD or LSD were given vehicle (VH group, olive oil, 1 mg/kg per day) or CsA (15 mg/kg per day) or CsA (15 mg/kg per day) plus LSRT (100 mg/L per day). Renal function, histopathology, TUNEL staining, plasma renin activity (PRA), and the expression of renin and EGF were studied.

RESULTS

Normal rats on the LSD showed significantly increased EGF expression (cortex, 2.6-fold; medulla, 1.7-fold) and significantly decreased EGF expression with the LSRT treatment compared with the rats treated with the NSD (cortex, 74.8 vs. 10%; medulla, 22.5 vs. 5%). In contrast, the CsA-treated rats on the LSD had a significantly lower EGF expression (cortex, 98 vs. 53%; medulla, 94 vs. 14%); however, concomitant administration of LSRT increased the EGF expression (cortex, 91- vs. 3.8-fold; medulla, 19- vs. 2.4-fold) compared with the rats on the NSD. In the normal and CsA-treated LSD rats, EGF expression was well correlated with PRA. In addition, EGF expression was well correlated with the interstitial fibrosis score (r = 0.664, P < 0.01) or number of TUNEL-positive cells (r = 0.822, P < 0.01) in CsA-treated LSD rats.

CONCLUSIONS

These results suggest that angiotensin II blockade with LSRT decreases EGF expression in normal rats on the LSD, but it protects EGF expression in CsA-induced nephrotoxicity. This finding provides a new perspective on the renoprotection of angiotensin II blockade in chronic CsA nephrotoxicity.

Determination of antigenic domain in GST fused major surface protein (Nc-p43) of Neospora caninum

The antigenic domain of the major surface protein (Nc-p43) of Neospora caninum was examined by polymerase chain reaction of its gene fragments and recombinant expression as GST fusion proteins. The fragments of Nc-p43 were as follow: a total open reading frame (OFR), T; OFR without signal sequence and C-terminal hydrophobic sequence, S; N-terminal 2/3 parts of S, A; C-terminal 2/3 parts, P; N-terminal 1/3 part, X; middle 1/3 part, Y; and C-terminal 1/3 part, Z, respectively. The DNA fragments were cloned into pGEX-4T vector. Recombinant plasmids transformed into Escherichia coli of BL21 pLysS (DE3) strain were induced to express GST or GST fused fragments of Nc-p43 such as 69 kDa protein for T, 66 kDa for S, 52 kDa for A, 53 kDa for P, and 40 kDa proteins for X, Y, and Z, respectively in SDS-PAGE. The Nc-p43 fragments of T, S, and P reacted with a bovine serum of neosporosis while those of A, X, Y, and Z together with GST did not in the western blot. These findings suggest that the antigenic domain of Nc-p43 of N. caninum may be localized in the C-terminal 2/3 parts. Together with A19 clone in SAG1 of Toxoplasma gondii (Nam et al., 1996), the P fragment of Nc-p43 could be used as efficient antigens to diagnose and differentiate those infections with both species.

CD28 costimulation is required not only to induce IL-12 receptor but also to render janus kinases/STAT4 responsive to IL-12 stimulation in TCR-triggered T cells

The activation of resting T cells for the acquisition of various functions depends on whether CD28 costimulatory signals are provided upon T cell receptor stimulation. Here, we investigated how CD28 costimulation functions to allow TCR-triggered resting T cells to acquire IL-12 responsiveness. When T cells are stimulated with low doses of anti-CD3 mAb, CD28 costimulation was required for the optimal levels of IL-12 receptor (IL-12R) expression. However, stimulation of T cells with high doses of anti-CD3 alone induced comparable levels of IL-12R expression to those induced upon CD28 costimulation. Nevertheless, there was a substantial difference in IL-12 responsiveness between these two groups of T cells: compared to anti-CD28-costimulated T cells, T cells that were not costimulated with anti-CD28 exhibited decreased levels of Janus kinases (JAK) JAK2/TYK2 and STAT4 phosphorylation and IFN-y production following IL-12 stimulation. Importantly, STAT6 phosphorylation following IL-4 stimulation was not decreased in anti-CD28-uncostimulated T cells. These resutls indicate that CD28 costimulation not only contributes to up-regulating IL-12R expression but is also required to render JAKs/STAT4 responsive to IL-12 stimulation.

An absolute requirement for STAT4 and a role for IFN-gamma as an amplifying factor in IL-12 induction of the functional IL-18 receptor complex

IL-12 and IL-18 are both proinflammatory cytokines that contribute to promoting Th1 development and IFN-gamma expression. However, neither IL-12R nor IL-18R is expressed as a functional complex on most resting T cells. This study investigated the molecular mechanisms underlying the induction of an IL-18R complex in T cells. Resting T cells expressed IL-18Ralpha chains but did not exhibit IL-18 binding sites as detected by incubation with rIL-18 followed by anti-IL-18 Ab, suggesting a lack of IL-18Rbeta expression in resting T cells. Although they also failed to express IL-12R, stimulation with anti-CD3 plus anti-CD28 generated IL-12R. Exposure of these cells to IL-12 led not only to up-regulation of IL-18Ralpha expression but also to induction of IL-18R binding sites on both CD4(+) and CD8(+) T cells concomitant with IL-18Rbeta mRNA expression. The IL-18 binding site represented a functional IL-18R complex capable of exhibiting IL-18 responsiveness. IL-12 induction of an IL-18R complex and IL-18Rbeta mRNA expression was not observed in STAT4-deficient (STAT4(-/-)) T cells and was substantially decreased in IFN-gamma(-/-) T cells. However, the failure of STAT4(-/-) T cells to induce an IL-18R complex was not corrected by IFN-gamma. These results indicate that STAT4 and IFN-gamma play an indispensable role and a role as an amplifying factor, respectively, in IL-12 induction of the functional IL-18R complex.

CD28 costimulation is required not only to induce IL-12 receptor but also to render janus kinases/STAT4 responsive to IL-12 stimulation in TCR-triggered T cells

The activation of resting T cells for the acquisition of various functions depends on whether CD28 costimulatory signals are provided upon T cell receptor stimulation. Here, we investigated how CD28 costimulation functions to allow TCR-triggered resting T cells to acquire IL-12 responsiveness. When T cells are stimulated with low doses of anti-CD3 mAb, CD28 costimulation was required for the optimal levels of IL-12 receptor (IL-12R) expression. However, stimulation of T cells with high doses of anti-CD3 alone induced comparable levels of IL-12R expression to those induced upon CD28 costimulation. Nevertheless, there was a substantial difference in IL-12 responsiveness between these two groups of T cells: compared to anti-CD28-costimulated T cells, T cells that were not costimulated with anti-CD28 exhibited decreased levels of Janus kinases (JAK) JAK2/TYK2 and STAT4 phosphorylation and IFN-y production following IL-12 stimulation. Importantly, STAT6 phosphorylation following IL-4 stimulation was not decreased in anti-CD28-uncostimulated T cells. These resutls indicate that CD28 costimulation not only contributes to up-regulating IL-12R expression but is also required to render JAKs/STAT4 responsive to IL-12 stimulation.

Influence of ligand binding to human cytochrome P-450 1A2: conformational activation and stabilization by alpha-naphthoflavone

Human cytochrome P-450 (P-450) 1A2 expressed in Escherichia coli is readily converted into non-native cytochrome P-420 (P-420) in the presence of detergents. alpha-Naphthoflavone (ANF) has been used to prevent P-450 1A2 inactivation to P-420 during purification. However, the mechanism by which ANF modulates P-450 1A2 is not clearly understood. We observed that recombinant human P-450 1A2 prepared in the absence of ANF has an approx. 5 times higher maximum catalytic activity in the O-deethylation of 7-ethoxycoumarin than that in the presence of ANF, with the same K(m) values. The results revealed that the enzyme purified with ANF is not catalytically fully active, indicating that ANF tightly binds to the enzyme, only to be dissociated by heat denaturation. Furthermore, the inactive P-420 form of the enzyme could be reconverted to P-450 by ANF in high concentrations of detergents. The reconversion was concentration-dependent, confirming ANF-induced regeneration of active P-450 1A2. The reconversion coincided with the conformational change of the enzyme including increased alpha-helix content. The conformation of P-450 1A2 was also stabilized by ANF, resulting in an approx. 5 degrees C increase in thermal stability.

The effects of famciclovir and epidural block in the treatment of herpes zoster

In our previous study, we concluded that an epidural blockade combined with intravenous acyclovir is very effective in treating the acute pain in herpes zoster and postherpetic neuralgia. We evaluated the efficacy of oral famciclovir and epidural blockade on the pain of herpes zoster, compared to acyclovir administered intravenously and epidural blockade. For this purpose, we examined a new group treated with famciclovir and epidural blockade to compare with the group treated with acyclovir and epidural blockade in our previously study. The changes in the intensity of pain, the number of days required for relief of pain, and the total duration of pain were checked. We compared the days required for relief of pain (DRP) and the total duration of pain (TDP) of this group with those of the previous studied group treated with acyclovir and epidural blockade. DRP was significantly less, but TDP was similar. DRP and TDP were significantly lower, if the patients were treated within 7 days of symptom onset. The patients had a shorter DRP regardless of pain type than the previously studied group treated with acycolvir and epidural blockade. For the severe and moderate pain grades, there was a shorter DRP from 100 to 10. TDP was not significantly different for the groups regardless of pain type or grade. We believe that famciclovir and epidural blockade are very effective in treating the pain of herpes zoster, with a view to shortening the period of acute pain, providing similar effects on the prevention of postherpetic neuralgia, and being convenient to administer, compared to intravenous acyclovir and epidural blockade in our previous study.

Clinical significance of anti-endothelial cell antibody in renal transplant recipients

In order to evaluate the role of anti-endothelial cell antibody (AECA) in acute rejection in renal transplantation, serum AECA IgG titers were measured in 68 healthy controls, 111 chronic hemodialysis (HD) patients and 58 first renal transplant recipients. The AECA titer in hemodialysis patients was higher than in healthy controls (13.9 +/- 5.0 vs. 4.8 +/- 2.3 U/mL, p < 0.01). In transplant recipients, AECA titers were not affected by dialysis mode (HD vs. CAPD vs. non-dialysis; 9.6 +/- 7.6 vs. 7.9 +/- 3.9 vs. 11.9 +/- 3.1 U/mL, p > 0.05). After renal transplantation, AECA titer was decreased significantly (vs. 4.7 +/- 3.6 U/mL. p < 0.01). The serum AECA IgG titers increased significantly in recipients with acute rejection (6.9 +/- 3.1 vs. 13.5 +/- 9.9 U/mL, p < 0.01), but decreased to 5.6 +/- 3.0 U/mL (p < 0.01) after formal rejection therapy. In the recipients with acute rejection (n = 27), the pre-renal transplant AECA titer was higher than in that without acute rejection (14.0 +/- 8.6 vs. 7.7 +/- 3.8 U/mL, p < 0.01). The results of this study lead us to conclude that pre- and post-renal transplant AECA titer might be a useful predictor for acute rejection and useful for monitoring acute rejection in renal transplant recipients.

High glucose-induced intercellular adhesion molecule-1 (ICAM-1) expression through an osmotic effect in rat mesangial cells is PKC-NF-kappa B-dependent

AIMS/HYPOTHESIS

Infiltration of mononuclear cells and glomerular enlargement accompanied by glomerular cell proliferation are very early characteristics of the pathophysiology of diabetes. To clarify the mechanism of early diabetic nephropathy, we measured [3H]-thymidine incorporation and cell numbers to show the influence of a high ambient glucose concentration and the osmotic effect on rat mesangial cell proliferation. We also measured the effect of high glucose on the expression of intercellular adhesion molecule-1 and vascular adhesion molecule-1 by flow cytometry and semiquantitative RT-PCR in mesangial cells and the adhesion of leukocytes to mesangial cells.

METHODS/RESULTS

Cells exposed to high D-glucose (30 mmol/l) caused an increase in [3H]-thymidine incorporation and cell numbers at 24 and 48 h and normalized at 72 h (p < 0.05), whereas these changes were not found in high mannitol (30 mmol/l), IL-1 beta, or TNF alpha-stimulated mesangial cells. Cells exposed to high-glucose (15, 30, or 60 mmol/l) or osmotic agents (L-glucose, raffinose and mannitol) showed that intercellular adhesion molecule-1 expression began to increase after 24 h, reached its maximum at 24 and 48 h and gradually decreased afterwards. The stimulatory effects of high glucose and high mannitol on mRNA expression were observed as early as 6 h and reached its maximum at 12 h. Up-regulation of ICAM-1 protein and mRNA was also found in IL-1-beta and TNF-alpha-stimulated mesangial cells. Neither vascular adhesion molecule-1 protein nor mRNA expression was, however, affected by high glucose and high mannitol. Notably, the protein kinase C inhibitors calphostin C and staurosporine reduced high glucose- or high mannitol-induced intercellular adhesion molecule-1 mRNA expression and high glucose-induced proliferation. Furthermore, the NF-kappa B inhibitor N-tosyl-L-phenylalanine chloromethyl ketone reduced high glucose- or high mannitol-induced intercellular adhesion molecule-1 mRNA expression and high glucose-induced proliferation. Results showed that high glucose (15, 30 mmol/l) or high concentrations of osmotic agents remarkably increased the number of adherent leukocytes to mesangial cells (p < 0.01) compared with control cells (5 mmol/l D-glucose). Functional blocking of intercellular adhesion molecule-1 on mesangial cells with rat intercellular adhesion molecule-1 monoclonal antibody, calphostin C, staurosporine, or N-tosyl-L-phenylalanine chloromethyl ketone significantly inhibited high glucose- or high mannitol-induced increase in leukocyte adhesion (p << 0.05).

CONCLUSION/INTERPRETATION

These results suggest that high glucose can upregulate intercellular adhesion molecule-1 protein and mRNA expression but not vascular adhesion molecule-1 expression in mesangial cells and promote leukocyte adhesion through up-regulation of intercellular adhesion molecule-1 through osmotic effect, possibly depending on the protein kinase C nuclear factor-kappa B (PKC-NF-kappa B) pathway. High glucose itself can also promote mesangial cell proliferation through the PKC-NF-kappa B pathways. We conclude that hyperglycaemia in itself seems to be an important factor in the development of early diabetic nephropathy.

Differential effects of N-acetyl-l-cysteine on IL-2- vs IL-12-driven proliferation of a T cell clone: implications for distinct signalling pathways

Using a T cell clone (2D6) capable of responding to IL-2 and IL-12, we compared the effects of NAC on IL-2 and IL-12-driven T cell proliferation. Addition of N-acetylcysteine (NAC) to 2D6 cultures did not affect IL-2 stimulated proliferation, but strikingly inhibited IL-12 stimulated proliferation. These differential NAC effects did not correlate with the patterns of the mitogen-activated protein kinase (MAPK) activation following cytokine stimulation and its regulation by NAC. Although a p38 MAPK inhibitor downregulated both IL-2- and IL-12-induced proliferation, this effect was seen at drug concentrations one order higher than those reportedly used to specifically inhibit p38 MAPK. The results suggest the existence of distinct signalling pathways and a common, indispensable signalling molecule in IL-2- and IL-12 driven T cell proliferation.

Clinical course of cytomegalovirus (CMV) viremia with and without ganciclovir treatment in CMV-seropositive kidney transplant recipients. Longitudinal follow-up of CMV pp65 antigenemia assay

This study was designed to evaluate the longitudinal history of cytomegalovirus (CMV) infection and to test the capacity of ganciclovir as effective therapy in CMV-seropositive renal transplant recipients. The CMV viremia was detected with CMV pp65 antigenemia assay in 153 renal transplants. The recipients were classified as having low-grade and high-grade CMV infections according to the severity of CMV infection. The recipients with low-grade CMV infections were observed without ganciclovir treatment, and the recipients with high-grade CMV infection were randomly assigned to ganciclovir-treated and untreated groups. The clinical course between low-grade and high-grade CMV infections was evaluated. All recipients with low-grade CMV infection (n = 62) showed spontaneous remission regardless of immunosuppresants. In high-grade CMV infection (n = 31), the ciclosporin A treated group (n = 11) showed no evidence of CMV disease, and the methylprednisolone-treated group (n = 8) showed CMV disease in 1 (25%) of 4 ganciclovir-untreated recipients. In the OKT3 group (n = 12), symptomatic CMV infection was observed in 6 (100%) ganciclovir-untreated recipients contrary to no CMV disease in the ganciclovir-treated group (p < 0.05). In conclusion, the CMV antigenemia assay is effective in monitoring CMV viremia, and ganciclovir treatment should be done during early CMV viremia in OKT3-treated recipients.

Effects of gamma radiation on sensory qualities, microbiological and chemical properties of salted and fermented squid

The effects of gamma radiation on sensory quality, microbial population, and chemical properties of salted and fermented squid were investigated. Squid (Todarodes pacificus) was sliced, washed, and then salted with 5, 10, and 20% (wt/wt) sodium chloride. Salted squid was irradiated with dosages of 0, 2.5, 5.0, and 10 kGy of gamma radiation and fermented at 15 degrees C for 50 days. Proximate composition, salinity, water activity, sensory evaluation, and total microbiological populations were examined. Chemical analyses providing information on degree of fermentation, such as amino nitrogen (AN), volatile basic nitrogen (VBN), trimethylamine (TMA), and hypoxanthine (Hx) were also conducted. Irradiated squid was not different in proximate composition, salinity, and water activity from nonirradiated squid. Sensory evaluation scores, total bacteria populations, and pH values were variable depending on salt concentration and irradiation dose. During fermentation, AN, VBN, TMA, and Hx contents increased rapidly as the salt concentration and irradiation dose decreased. Specifically, these chemical compounds of salted and fermented squid prepared with 10% salt and 10 kGy of gamma radiation maintained the appropriate level of fermentation. The present results showed that the combination of low salt concentration (10%) and gamma radiation was effective in processing salted and fermented squid and extending its shelf life compared to control (20% of salt) without adding any food additives.

Expression of bone morphogenetic protein receptors type-IA, -IB and -II correlates with tumor grade in human prostate cancer tissues

Bone morphogenetic proteins (BMPs) are potential regulators of prostate cancer cell growth and metastasis that signal through an interaction with BMP membrane receptors (BMPRs) type I and type II. In the present study, Western blot and immunohistochemical analysis of BMPRs were carried out in benign and malignant human prostate tissues to explain the loss of BMP response in human prostate cancer cells. The results demonstrated that the benign prostate specimens expressed high levels of all three BMPRs. In normal prostate, BMPRs were localized predominantly to epithelial cells. Among prostate cancer specimens, well-differentiated cancers were positive for the expression of BMPR-II, BMPR-IA, and BMPR-IB, for the most part. In contrast, only 1 of 10 poorly differentiated prostate cancer cases was positive for each of the three BMPRs (P < 0.005 for all three receptors). Taken together, these results indicate that human prostate cancer cells frequently exhibit loss of expression of BMPRs and suggest that loss of BMPRs may play an important role during the progression of prostate cancer.

Bupivacaine-sparing effect of fentanyl in spinal anesthesia for cesarean delivery

BACKGROUND AND OBJECTIVES

Visceral pain decreases in cesarean patients under spinal anesthesia when the dose of local anesthetic is increased. However, larger doses of local anesthetic are associated with higher sensory blocks. We hypothesized that the addition of fentanyl could reduce the dose of bupivacaine necessary to achieve adequate surgical anesthesia.

METHODS

Two double-blinded, sequential, prospective studies were performed on 120 patients. In the preliminary study, the patients received 8, 10, or 12 mg of 0.5% hyperbaric bupivacaine intrathecally. In the second, main study, they received each bupivacaine dose with 10 microg of fentanyl. Each group consisted of 20 patients, and the groups were identified as B8, B10, B12, BF8, BF10, and BF12. Sensory and motor block, intraoperative pain defined by visual analogue scale (VAS), muscle relaxation, and side effects were assessed. We also measured the sensory and motor recovery and the onset of pain in the postanesthesia care unit (PACU).

RESULTS

Maximal block level and incidence of high block (> or = T1) were higher in the 12-mg groups. There was intraoperative pain in 35% of the B8 patients and 20% of the B10 patients, but none in the B12 patients and all fentanyl groups. Incidences of other side effects were not different. The addition of fentanyl to bupivacaine significantly delayed the onset of postoperative pain and sensory recovery, but motor recovery time did not change with additional fentanyl.

CONCLUSIONS

The optimal dose of hyperbaric bupivacaine to produce surgical anesthesia was 12 mg, which was accompanied by high sensory block. With the addition of 10 microg of fentanyl, the dose of bupivacaine could be reduced to 8 mg in spinal anesthesia for cesarean delivery.

The possible role of c-fos protein in hypothalamus in sleep disturbance in chronic uremic rats

Sleep disturbance is very common in patients with chronic renal failure, but its mechanism is not clear. The activity of c-fos protein (FOS) in ventrolateral preoptic neurons (VLPO) is associated with the sleep pattern. The purpose of this study was to evaluate the relationship between sleep disturbance and the expression of FOS in VLPO of chronic uremic rats. Chronic uremia was induced by the 5/6 nephrectomized model. The movements of the rats were measured with infrared monitoring during the daytime (8.00-20.00) and nighttime (20.00-8.00). Rats were killed at 10.00 or 16.00 h for the daytime (uremic rats 7, control 8) and at 22.00 h for the nighttime (uremic rats 7, control 9). The expression of FOS in VLPO was examined with the immunohistochemical method. The number of recorded daytime movements in uremic rats was significantly higher than in control rats (458 +/- 185 vs. 222 +/- 41, p < 0.001), but the number of recorded nighttime movements in uremic rats was lower than in control rats (949 +/- 430 vs. 1,618 +/- 261, p < 0.001). In the daytime, the number of FOS immunoreactive cells in uremic rats was lower than in control rats (18.4 +/- 5.3 vs. 42.8 +/- 6.3, p < 0. 001), but there was no difference between two groups in the nighttime (10.8 +/- 8.4 vs. 12.5 +/- 5.1, p = 0.62). There was a strong negative correlation between the number of recorded movements and the number of FOS immunoreactive cells in VLPO (r = -0.700, p < 0.001). This finding suggests that sleep disturbances in chronic uremic rats might be related to the decreased expression of FOS in VLPO.

A novel function of Valpha14+CD4+NKT cells: stimulation of IL-12 production by antigen-presenting cells in the innate immune system

The balance between Th1 and Th2 development is determined by IL-4 and IL-12. While the role for CD4+ NK1.1+ T (NKT) cells in influencing this balance has been recognized based on their capacity to produce IL-4, it is unknown how IL-12 is produced in the innate immune system in which they participate. This study demonstrates that Ag-activated CD4+ NKT cells express CD40 ligand (CD40L) (CD154), which engages CD40 on APC and stimulates them to produce IL-12. Culture of B cell-depleted spleen cells from C57BL/6 mice with alpha-galactosylceramide (alpha-GalCer) capable of selectively stimulating Valpha14/Jalpha281+ NKT cells resulted in the production of IL-12 together with IFN-gamma and IL-4. alpha-GalCer-induced IL-12 production occurred in I-Abbeta-deficient mice, but not in beta2-microglobulin-deficient and Valpha14/Jalpha281 TCR-deficient mice, and was inhibited by anti-CD40L mAb. Of CD4+ and CD4- NKT cells, the capacity to express CD40L/CD154 and trigger IL-12 production following alpha-GalCer stimulation was exhibited preferentially by the CD4+ NKT subset. IL-12 production was also observed in alpha-GalCer-treated mice. Production of IL-12 preceded IFN-gamma production, and IL-12 was required for IFN-gamma, but not IL-4, production. A stimulatory/inhibitory relationship existed between IL-12 and IL-4 production. These results illustrate a novel function of CD4+ NKT cells that could be involved in the regulation of Th1 vs Th2 development.

Crystallization and preliminary X-ray crystallographic analysis of deoxycytidylate hydroxymethylase from bacteriophage T4

Deoxycytidylate hydroxymethylase from bacteriophage T4 is a homodimeric enzyme in which each polypeptide chain consists of 246 amino-acid residues. It has been crystallized in the presence of its substrate, deoxycytidine monophosphate, at room temperature using sodium citrate as precipitant. The crystals are monoclinic, belonging to space group C2, with unit-cell parameters a = 174.22, b = 53.12, c = 75.17 A, beta = 115.29 degrees. The asymmetric unit contains one homodimer, with a corresponding Vm of 2.65 A3 Da-1 and solvent content of 54%. Native diffraction data to 1.6 A resolution have been collected from two crystals using synchrotron radiation.

Requirement for distinct Janus kinases and STAT proteins in T cell proliferation versus IFN-gamma production following IL-12 stimulation

While IL-12 is known to activate JAK2 and TYK2 and induce the phosphorylation of STAT4 and STAT3, little is known regarding how the activation of these signaling molecules is related to the biologic effects of IL-12. Using an IL-12-responsive T cell clone (2D6), we investigated their requirements for proliferation and IFN-gamma production of 2D6 cells. 2D6 cells could be maintained with either IL-12 or IL-2. 2D6 lines maintained with IL-12 (2D6(IL-12)) or IL-2 (2D6(IL-2)) exhibited comparable levels of proliferation, but produced large or only small amounts of IFN-gamma, respectively, when restimulated with IL-12 after starvation of either cytokine. 2D6(IL-12) induced TYK2 and STAT4 phosphorylation. In contrast, their phosphorylation was marginally induced in 2D6(IL-2). The reduced STAT4 phosphorylation was due to a progressive decrease in the amount of STAT4 protein along with the passages in IL-2-containing medium. 2D6(IL-12) and 2D6(IL-2) similarly proliferating in response to IL-12 induced comparable levels of JAK2 activation and STAT5 phosphorylation. JAK2 was associated with STAT5, and IL-12-induced STAT5 phosphorylation was elicited in the absence of JAK3 activation. These results indicate that IL-12 has the capacity to induce/maintain STAT4 and STAT5 proteins, and that TYK2 and JAK2 activation correlate with STAT4 phosphorylation/IFN-gamma induction and STAT5 phosphorylation/cellular proliferation, respectively.

Detection of human papillomavirus in warty carcinoma of the uterine cervix: comparison of immunohistochemistry, in situ hybridization and in situ polymerase chain reaction methods

Warty carcinoma of the uterine cervix is a very rare specific variant of invasive squamous cell carcinoma, usually described as a hybrid feature of condyloma with invasive squamous cell carcinoma. Besides having the koilocytes and maturation of squamous epithelium, there is unequivocal stromal invasion. The feathery surface seems to be characteristic of warty carcinoma, differentiating it from condylomata acuminata or verrucous carcinoma. Using in situ polymerase chain reaction (IS-PCR) and in situ hybridization (ISH) as well as an immunohistochemical technique (IHC), we determined the amplification and expression of several human papilloma virus (HPV) types (6, 11, 33, 16 and 18) in nine warty carcinomas of the uterine cervix. We found amplified HPV predominantly in the nuclei of the feathery surface in all cases only when IS-PCR was applied, while it was detected only in five (55.6%) or six cases (66.7%) by conventional IHC or ISH, respectively. We found multiple types in the same lesion in six cases (66.7%) by IS-PCR, in comparison with ISH which detected a lower incidence (22.2%). This finding of coinfection is more consistent with that seen in low-grade squamous intraepithelial lesions (LSILs) of the uterine cervix than in high SIL. It is important to be aware of these distinct lesions in postmenopausal women with their characteristic feathery and thin surface, as well as a hybrid form of exophytic condyloma and stromal invasion, and frequent coinfection of multiple different HPVs as a type of LSILs.

Enhancement of bioavailability of ketoprofen using dry elixir as a novel dosage form

To enhance the dissolution rate and bioavailability of poorly water-soluble ketoprofen, a novel oral dosage form of ketoprofen, termed ketoprofen dry elixir, was developed by the spray-drying technique. Ketoprofen, dextrin, and sodium lauryl sulfate were dissolved in an ethanol-water mixture (20:25 w/w) and thereafter spray-dried to form the ketoprofen dry elixir. Comparative studies on the in vitro dissolution and in vivo adsorption of ketoprofen in the form of dry elixir and powder were carried out. Ketoprofen in the dry elixir completely dissolved within 5 min. On the other hand, only about 50.1% of ketoprofen powder alone dissolved during 60 min. The initial dissolution rate of ketoprofen in the dry elixir markedly increased in distilled water at 37 degrees C, becoming fourfold higher than that of ketoprofen powder alone. The maximal plasma concentration of ketoprofen (Cmax) and the area under the concentration-time curve from zero to 8 hr (AUC0-8 hr) after the oral administration of dry elixir increased about 3.2- (24.6 versus 7.6 micrograms/ml) and 2.2-(38.4 versus 17.3 micrograms hr/ml) fold compared with powder alone. It was obvious that ketoprofen dry elixir might be a useful solid dosage form to improve the dissolution rate and bioavailability of poorly water-soluble ketoprofen.

Loss of expression of transforming growth factor-beta receptors is associated with poor prognosis in prostate cancer patients

Transforming growth factor beta (TGF-beta) is a potent inhibitor of proliferation in most cells and exerts its effects through an interaction with membrane receptors type I (TGF-betaRI) and type II (TGF-betaRII). Recently, we have demonstrated a correlation between the loss of expression of TGF-betaRI and TGF-betaRII and increasing Gleason score in archival human prostate cancer tissues. To evaluate the potential prognostic value of this observation, the present study investigated the expression of TGF-beta receptors in association with disease progression after the initial diagnosis in 52 archival human prostate cancer tissues. The expression of both TGF-betaRI and TGF-betaRII was correlated with the Gleason score, clinical tumor stage, 4-year survival rate, and serological recurrence rate after radical prostatectomy. Results revealed that there was a significant association between the Gleason score and the loss of expression of TGF-betaRI (P < 0.025) and TGF-betaRII (P < 0.01). However, only the loss of TGF-betaRI expression showed a statistically significant association with the clinical tumor stage (P < 0.05), 4-year survival rate (P < 0.05), and serological recurrence rate after radical prostatectomy (P < 0.025). Therefore, these data indicate that the loss of TGF-betaRI expression as measured by immunohistochemical staining may be a potential prognostic marker in prostate cancer patients.

A critical role for IL-18 in the proliferation and activation of NK1.1+ CD3- cells

Like IL-12, IFN-gamma-inducing factor/IL-18 has been shown to stimulate T cells for IFN-gamma production and growth promotion. Considering the NK-stimulatory capacity of IL-12, we investigated the effect of IL-18 on NK lineage cells. A CD4- CD8- surface Ig- Ia- fraction of freshly prepared C57BL/6 spleen cells proliferated strikingly in response to combinations of IL-12 + IL-18 or IL-2 + IL-18, but not to the individual cytokines or IL-2 + IL-12. Cells proliferating in response to IL-2 + IL-18 were NK1.1+ CD3-, whereas IL-12 + IL-18-responsive cells were NK1.1- CD3-. Restimulation of the former cells with IL-12 + IL-18 or the latter cells with IL-2 + IL-18 resulted in the generation of NK1.1- CD3- or NK1.1+ CD3- cells, respectively. Moreover, a NK1.1+ CD3- CD4- CD8- surface Ig- Ia- population isolated from spleen cells was found to form NK1.1+ CD3- or NK1.1- CD3- blasts by stimulation with IL-2 + IL-18 or IL-12 + IL-18, respectively, and the NK1.1 positivity on these blasts was again reversed after restimulation with an alternative combined stimulus. Both types of blasts produced enormously large amounts of IFN-gamma in response to IL-12 + IL-18 and exhibited strikingly high levels of NK activity. These results indicate that IL-18 plays an obligatory role in inducing proliferation and activation of NK1.1+ CD3- CD4- CD8- cells and that the expression of the NK1.1 marker is reversible, depending on the cytokine used for stimulation in combination with IL-18.

Differential capacities of CD4+, CD8+, and CD4-CD8- T cell subsets to express IL-18 receptor and produce IFN-gamma in response to IL-18

IL-12 and IL-18 have the capacity to stimulate IFN-gamma production by T cells. Using a T cell clone, we reported that IL-18 responsiveness is generated only after exposure to IL-12. Here, we investigated the induction of IL-18 responsiveness in resting CD8+, CD4+, and CD4-CD8- T cells. Resting T cells respond to neither IL-12 nor IL-18. After stimulation with anti-CD3 plus anti-CD28 mAbs, CD8+, CD4+, and CD4-CD8- T cells expressed IL-12R, but not IL-18R, and produced IFN-gamma in response to IL-12. Cultures of T cells with anti-CD3/anti-CD28 in the presence of rIL-12 induced IL-18R expression and IL-18-stimulated IFN-gamma production, which reached higher levels than that induced by IL-12 stimulation. However, there was a substantial difference in the expression of IL-18R and IL-18-stimulated IFN-gamma production among T cell subsets. CD4+ cells expressed marginal levels of IL-18R and produced small amounts of IFN-gamma, whereas CD8+ cells expressed higher levels of IL-18R and produced more IFN-gamma than CD4+ cells. Moreover, CD4-CD8- cells expressed levels of IL-18R comparable to those for CD8+ cells but produced IFN-gamma one order higher than did CD8+ cells. These results indicate that the induction of IL-18R and IL-18 responsiveness by IL-12 represents a mechanism underlying enhanced IFN-gamma production by resting T cells, but the operation of this mechanism differs depending on the T cell subset stimulated.

Induction of V3-specific cytotoxic T lymphocyte responses by HIV gag particles carrying multiple immunodominant V3 epitopes of gp120

Effort to develop a vaccine to prevent infection of human immunodeficiency virus (HIV) have focused on the induction of neutralizing antibodies. In our previous study, we reported that chimeric gag-env virus-like particles (VLPs) induce neutralizing antibodies which block HIV infection. In addition to the neutralizing antibodies, the cytotoxic T-lymphocyte (CTL) response is considered to be another major immune defense mechanism required for recovery from many different viral infections. In the present study, we have constructed chimeric fusion proteins using HIV-2 gag precursor protein with (1) four neutralizing epitopes from HIV-1 gp160; (2) three tandem copies of consensus V3 domain, which have been derived from 245 different isolates of HIV-1 and carries both the principal neutralizing determinant (PND) and CTL epitopes; and (3) V3 domains from HIV-1IIIB, HIV-1MN, HIV-1RF, and HIV-1SF2. These chimeric fusion proteins were expressed in a large quantity within insect cells, and released as VLPs into the cell culture medium. The purified gag-env VLPs from all three constructs appear to be spherical particles similar to immature HIV but slightly larger than the gag VLPs. Immunoprecipitation analysis showed that the chimeric proteins were recognized not only by HIV-1 positive patient sera, but also by monoclonal and polyclonal antisera raised against V3 peptides of HIV-1IIIB, HIV-1MN, HIV-1RF, and the gp120 antiserum against HIV-1SF2. Balb/C mice immunized with these chimeric VLPs successfully induced CTL activity against V3 peptide-stimulated target cells. In addition, a high degree of cross-reactivity was observed among the four different strains of HIV-1 V3 domain, indicating that the tandem multiple consensus V3 peptide sequence carried by HIV-2 gag can be used as a potential HIV vaccine against various HIVs.

A mechanism underlying synergy between IL-12 and IFN-gamma-inducing factor in enhanced production of IFN-gamma

IL-12 and IFN-gamma-inducing factor (IGIF) have the capacity to stimulate IFN-gamma production by T cells. Using an IL-12-responsive T cell clone, 2D6, we investigated how these two cytokines collaborate for IFN-gamma production. 2D6 obtained from cultures containing rIL-12 produced IFN-gamma in response to rIGIF. 2D6 from cultures deprived of IL-12 for 24 h produced only marginal levels of IFN-gamma production following stimulation with either rIL-12 or rIGIF alone. However, simultaneous stimulation of these 2D6 cells with both cytokines resulted in strikingly enhanced levels of IFN-gamma production. 2D6 could also be maintained in the presence of rIL-2 instead of rIL-12. 2D6 lines maintained with rIL-12 (2D6(IL-12)) or rIL-2 (2D6(IL-2)) exhibited differential IGIF responsiveness: both lines responded similarly to rIL-2 or rIL-12, whereas the 2D6(IL-12) or 2D6(IL-2) exhibited high or marginal IGIF responsiveness, respectively. The 2D6(IL-12) line expressed IGIF receptor (IGIFR), whereas the 2D6(IL-2) did not. Overnight exposure of the 2D6(IL-12) to rIL-2 reduced IGIFR expression and conversely, exposure of the 2D6(IL-2) to rIL-12 restored IGIFR expression. IGIFR expression by these 2D6 lines correlated with the capacity to produce IFN-gamma in response to rIGIF. Purified naive T cells stimulated with anti-CD3 plus anti-CD28 mAb and subsequently cultured with rIL-12 were also found to express IGIFR and induce enhanced IFN-gamma production following IGIF stimulation. These results indicate that the induction of IGIFR by IL-12 represents one of the mechanisms underlying the synergy between IL-12 and IGIF in IFN-gamma production.

A mechanism underlying synergy between IL-12 and IFN-gamma-inducing factor in enhanced production of IFN-gamma

IL-12 and IFN-gamma-inducing factor (IGIF) have the capacity to stimulate IFN-gamma production by T cells. Using an IL-12-responsive T cell clone, 2D6, we investigated how these two cytokines collaborate for IFN-gamma production. 2D6 obtained from cultures containing rIL-12 produced IFN-gamma in response to rIGIF. 2D6 from cultures deprived of IL-12 for 24 h produced only marginal levels of IFN-gamma production following stimulation with either rIL-12 or rIGIF alone. However, simultaneous stimulation of these 2D6 cells with both cytokines resulted in strikingly enhanced levels of IFN-gamma production. 2D6 could also be maintained in the presence of rIL-2 instead of rIL-12. 2D6 lines maintained with rIL-12 (2D6(IL-12)) or rIL-2 (2D6(IL-2)) exhibited differential IGIF responsiveness: both lines responded similarly to rIL-2 or rIL-12, whereas the 2D6(IL-12) or 2D6(IL-2) exhibited high or marginal IGIF responsiveness, respectively. The 2D6(IL-12) line expressed IGIF receptor (IGIFR), whereas the 2D6(IL-2) did not. Overnight exposure of the 2D6(IL-12) to rIL-2 reduced IGIFR expression and conversely, exposure of the 2D6(IL-2) to rIL-12 restored IGIFR expression. IGIFR expression by these 2D6 lines correlated with the capacity to produce IFN-gamma in response to rIGIF. Purified naive T cells stimulated with anti-CD3 plus anti-CD28 mAb and subsequently cultured with rIL-12 were also found to express IGIFR and induce enhanced IFN-gamma production following IGIF stimulation. These results indicate that the induction of IGIFR by IL-12 represents one of the mechanisms underlying the synergy between IL-12 and IGIF in IFN-gamma production.

Mixed hepatoblastoma in an adult--a case report and literature review

Hepatoblastoma is thought to originate from embryonal hepatic tissue, and most of these tumors occur in children under the age of 2 years. Hepatoblastoma in adults is extremely rare, and the prognosis is much worse than the mixed hepatoblastoma of childhood. We experienced a case of mixed hepatoblastoma in a 51 year old female patient. She had been suffering from a mild pain and a palpable lump in the epigastric area. Serum AFP was 43,850 ng/ml. Computerized tomography and selective abdominal angiography showed a large low-density mass. With a suspicion of hepatocellular carcinoma of the left lobe, a left lateral segmentectomy was performed. The external surface showed a huge protruding mass and the capsule was previously ruptured. On section, the tumor was a 11 x 7 cm sized expanding mass which had a variegated surface composed of yellow-white friable tissue with multifocal hemorrhagic areas. Microscopic examination revealed a tumor consisted of epithelial and mesenchymal elements. The mesenchymal cells were spindle in shape and proliferated over the whole tumor with focal osteosarcomatous differentiation. The epithelial components showed well-differentiated hepatocellular carcinoma-like areas, poorly differentiated acinar or tubular structures.

Synergy between CD28 and CD9 costimulation for naive T-cell activation

Our previous study demonstrated that CD9 is expressed on most mature naive T-cells and delivers a potent costimulatory signal that functions independently of CD28. Here, we investigated whether this CD9-mediated signal is different from the CD28-mediated signal in the mode of costimulation and whether both signals function synergistically for T-cell activation. Anti-CD9 or anti-CD28 monoclonal antibody (mAb) increased [3H]TdR incorporation of naive T-cells in the absence of antigen-presenting cells (APC) when coimmobilized with submitogenic doses of anti-CD3 mAb. The levels of costimulation induced by ligation of CD9 and CD28 were comparable. However, the costimulatory effect differed between soluble anti-CD9 and CD28 mAb. A soluble form of anti-CD28 mAb could costimulate anti-CD3-triggered T-cells, whereas soluble anti-CD9 mAb failed to costimulate. Although anti-CD28 costimulated naive T-cells treated with phorbol myristate acetate (PMA) instead of anti-CD3 mAb, a combination of PMA plus anti-CD9 mAb could not induce T-cell activation. The combined costimulation of anti-CD3-triggered T-cells with anti-CD9 and anti-CD28 mAbs resulted in strikingly enhanced [3H]TdR uptake and lymphokine (IL-2 and IFN-gamma) production when compared to those induced by each costimulation. These results suggest that CD9 and CD28 induce T-cell costimulation using different signaling pathways, thereby inducing synergy in T-cell activation.

Establishment of an IL-12-responsive T cell clone: its characterization and utilization in the quantitation of IL-12 activity

We previously demonstrated that proliferation of terminally differentiated Th1 clones depends primarily on an interleukin-12 (IL-12)-paracrine mechanism mediated by their interactions with antigen-presenting cells (APC) rather than on an IL-2-autocrine mechanism. Such a Th1 clone (4-86, C57BL/6 origin) was cultured with recombinant IL-12 (rIL-12) in the absence of either antigen or APC. Some cells survived for several passages of culture with only rIL-12, and by limiting dilution, several clones highly reactive to rIL-12 alone were obtained. One of these clones, designated 2D6, was found to proliferate strongly in response to less than 1 pg/mL of rIL-12. This clone exhibited the following surface phenotypes: CD3+, T cell receptor (TCR) alpha beta+, Vbeta11+, NK-1.1-; CD4-CD8-; LFA-1+, ICAM-1+; and CD28+, CD80+, CD86+, CTLA-4-. In accordance with high responsiveness to IL-12, 2D6 cells were also found to express IL-12 receptor (IL-12R) as detected by incubation with rIL-12 and then staining with anti-IL-12 monoclonal antibody (mAb). Stimulation of 2D6 with rIL-12 resulted in the expression of interferon-gamma (IFN-gamma) and IL-10 mRNAs and production of these cytokines. The 2D6 clone responded to IL-2 (vigorously), IL-7 (moderately), and IL-4 (mildly) in addition to IL-12. However, the Ab capture assay using anti-IL-12 mAb enabled us to quantify IL-12-specific activity contained in a given sample. Thus, this study describes the unique features of the IL-12-responsive T cell clone and demonstrates the utilization of this clone in the quantitation of a specific IL-12 activity.

B cells regulate CD40 ligand-induced IL-12 production in antigen-presenting cells (APC) during T cell/APC interactions

Although stimulation of freshly isolated murine spleen cells with anti-CD3 mAb or Con A failed to generate IL-12 production, the same cell preparations depleted of B cells produced IL-12. Addition of normal B cells inhibited IL-12 production in a cell number-dependent manner. IL-12 production was dependent on the presence of CD4+, but not of CD8+, T cells, and inhibited by addition of anti-CD40 ligand (CD40L) mAb. Anti-CD3 or Con A stimulation induced CD40L expression only on CD4+ T cells, which was inhibited in the presence of B cells. IL-12 production was also induced by interactions between CD40L-transfected Chinese hamster ovary cells and splenocytes depleted of T and B cells, but not of APC, indicating CD40L-induced IL-12 production by APC. The involvement of CD40 molecules was examined by comparing the ability of cells from CD40-deficient (CD40 -/-) and wild-type mice (CD40 +/+) to produce IL-12. Spleen cells from CD40 -/- and CD40 +/+ mice produced comparable amounts of IL-12 in response to bacterial stimuli. However, the B cell-depleted fraction from CD40 -/- mice failed to produce IL-12 when stimulated with anti-CD3 or Con A or when cocultured with CD40L-expressing Chinese hamster ovary cells. These results indicate that CD40L expressed on activated T cells induces APC to produce IL-12 through CD40/CD40L interaction, but this pathway is competitively inhibited by CD40+ B cells incapable of producing IL-12 upon stimulation with CD40L. Thus, this might represent a novel mechanism underlying the regulation of cell-mediated and humoral immunity.

B cells regulate CD40 ligand-induced IL-12 production in antigen-presenting cells (APC) during T cell/APC interactions

Although stimulation of freshly isolated murine spleen cells with anti-CD3 mAb or Con A failed to generate IL-12 production, the same cell preparations depleted of B cells produced IL-12. Addition of normal B cells inhibited IL-12 production in a cell number-dependent manner. IL-12 production was dependent on the presence of CD4+, but not of CD8+, T cells, and inhibited by addition of anti-CD40 ligand (CD40L) mAb. Anti-CD3 or Con A stimulation induced CD40L expression only on CD4+ T cells, which was inhibited in the presence of B cells. IL-12 production was also induced by interactions between CD40L-transfected Chinese hamster ovary cells and splenocytes depleted of T and B cells, but not of APC, indicating CD40L-induced IL-12 production by APC. The involvement of CD40 molecules was examined by comparing the ability of cells from CD40-deficient (CD40 -/-) and wild-type mice (CD40 +/+) to produce IL-12. Spleen cells from CD40 -/- and CD40 +/+ mice produced comparable amounts of IL-12 in response to bacterial stimuli. However, the B cell-depleted fraction from CD40 -/- mice failed to produce IL-12 when stimulated with anti-CD3 or Con A or when cocultured with CD40L-expressing Chinese hamster ovary cells. These results indicate that CD40L expressed on activated T cells induces APC to produce IL-12 through CD40/CD40L interaction, but this pathway is competitively inhibited by CD40+ B cells incapable of producing IL-12 upon stimulation with CD40L. Thus, this might represent a novel mechanism underlying the regulation of cell-mediated and humoral immunity.

Loss of expression of transforming growth factor beta type I and type II receptors correlates with tumor grade in human prostate cancer tissues

Transforming growth factor beta1 (TGF-beta1) is a potential regulator of prostate cancer cell growth that signals through a heteromeric complex composed of type I and type II receptors. In the present study, an attempt was made to establish a correlation between expression of TGF-beta receptors and tumor grade in archival human prostate cancer tissues. To this end, immunohistochemical studies for TGF-beta receptors were carried out on 32 cases of human prostate cancer and 8 samples of benign human prostate. In both benign and malignant human prostate tissues, immunoreactivity for both type I and type II receptors was detected predominantly in epithelial cells. In addition, there was an inverse correlation between the loss of expression of TGF-beta1 type I and type II receptors and the tumor grade. Of the 32 prostate cancer cases screened, staining was completely absent in four samples for type II receptor (P < 0.05) and eight samples for type I receptor (P < 0.025). In contrast, all eight samples of benign prostate tissues investigated in this study showed strong staining for both type I and type II receptors. These results, taken together, indicate that human prostate cancer cells frequently have loss of expression of TGF-beta type I and/or type II receptors. Furthermore, these observations provide a potential mechanism for prostate cancer cells to escape the growth-inhibitory effect of TGF-beta.

Cellulose degradation and ethanol production by thermophilic bacteria using mineral growth medium

Growth of thermophilic cellulase-utilizing bacteria in a vitamin-free growth medium is reported for both a previously described strain, Clostridium thermoclelum 31549, and now isolates HJA1 and HJA2. Formation of fermentation products with and without vitamins was similar for strains HJA1 and HJA2 as well as for the enrichment cultures from which these stains were derived. Strain HJA2 was maintained in continuous culture on a vitamin-free mineral medium with Avicel as the carbon source for over a week. At a 38 h residence time, Avicel conversion was higher (81%) at pH 6.42 than at pH 6.97 (73%) or at 6.01 (58%). Ethanol and acetate were produced in significant amounts by strain JHA2 at all pH values tested (6.97, 6.42, 6.01). Lactic acid was the primary fermentation product at pH 6.97, but was not a significant product at both the lower values. Efforts to grow thermophilic, cellulose-utilizing bacteria at pH < 6.0 were unsuccessful for described strains, new isolates, and enrichment cultures.

Transforming growth factor-beta1 is a mediator of androgen-regulated growth arrest in an androgen-responsive prostatic cancer cell line, LNCaP

LNCaP is an androgen-responsive prostatic cancer cell line that exhibits a bell-shaped growth response to increasing doses of dihydrotestosterone (DHT) in culture. Although the precise mechanism responsible for this growth response to androgen stimulation remains unclear, many studies have suggested that androgen modulates the level of various growth factors. In the present study, the role of transforming growth factor-beta (TGF-beta) in mediating the androgen-regulated growth arrest of LNCaP cells was investigated. The following concentrations of DHT were used: 0, 10(-12), 10(-10), and 10 (-7) M. These concentrations were selected because they represent the zero DHT control, the low-proliferative dose, the high-proliferative dose, and the growth arrest dose, respectively. Results of RT-PCR showed that LNCaP cells express TGF-beta1 but not -beta2 and -beta3 messenger RNA. Competitive quantitative RT-PCR demonstrated that the level of TGF-beta1 messenger RNA increased approximately 7-fold when cells were treated with 10(-7) M DHT. Results of Western blot analysis showed a dramatic increase in the level of latent TGF-beta1 protein in cell lysates with increasing concentrations of DHT. In addition, results of enzyme-linked immunoadsorbent assay for TGF-beta1 indicated that treatment of LNCaP cells with DHT led to a dose-dependent increase in both total and biologically active TGF-beta1 in the conditioned media. To determine the role of TGF-beta1 in regulating LNCaP proliferation, the action of TGF-beta1 was blocked by two different but complementary approaches. First, TGF-beta1 neutralizing antibody was added to the culture medium with varying concentrations of DHT. Second, mannose-6-phosphate, which has been demonstrated to inhibit the activation of latent TGF-beta1, was added in a similar manner to the culture. Results demonstrated that the characteristic bell- shaped growth response following treatment with increasing doses of DHT was converted to a linear dose-response curve as the growth of inhibition seen at the high dose by DHT was abolished. These observations, taken together, indicate that TGF-beta1 mediates at least in part the growth arrest observed at the high concentration of DHT in LNCaP cells.

Modulation of sensitivity to transforming growth factor-beta 1 (TGF-beta 1) and the level of type II TGF-beta receptor in LNCaP cells by dihydrotestosterone

Transforming growth factor-beta 1 (TGF-beta 1) and androgen are potential physiological regulators of prostate cancer cells. In the present study, we have used LNCaP cells as a model of androgen-responsive prostate cancer to investigate the effects of dihydrotestosterone (DHT) on the sensitivity to TGF-beta 1. The ability of LNCaP cells to respond to TGF-beta has been controversial. In some studies, LNCaP cells were insensitive to TGF-beta 1 while, in others, they were sensitive to the growth inhibitory effect of TGF-beta 1. The present study was carried out to establish androgenic conditions that rendered LNCaP cells sensitive to TGF-beta 1. Cells were cultured in phenol-red-free RPMI 1640 medium supplemented with 10% charcoal-stripped fetal bovine serum. DHT was added at the following concentrations: 0, 10(-12), 10(-10), and 10(-7) M. These concentrations were selected because they represent the zero DHT control, the low-proliferative dose, the high-proliferative dose, and the growth-arrest dose, respectively. The effects of TGF-beta 1 observed on LNCaP cells included inhibition of cell proliferation, decrease in cell viability, alteration in cell morphology, and enhancement of gene transcriptional activity through activation of a TGF-beta responsive promoter. Of the various DHT concentrations investigated in this study, these effects of TGF-beta 1 on LNCaP cells were consistently demonstrated only at 10(-10) M. At other concentrations, the effects of TGF-beta 1 were either minimal or undetectable. Accompanying these effects of TGF-beta 1, a low but statistically significant level of TGF-beta 1-specific binding and an increased protein level of TGF-beta receptor type II were detected by a competitive binding assay and Western blot analysis respectively. These results indicate that LNCaP cells can be induced by DHT to respond to TGF-beta 1 and that DHT modulates the sensitivity to TGF-beta 1 and the level of TGF-beta receptor type II in these cells.

Expression and localization of transforming growth factor-beta receptors type I and type II in the rat ventral prostate during regression

Of the three ubiquitously expressed transforming growth factor-beta (TGF beta) receptors, only type I and type II receptors contain serine/threonine kinase activity and have a direct role in TGF beta signal transduction. In the prostate, it has been reported that the level of type III receptor expression increases transiently after castration. However, the relationship between the TGF beta signaling receptors, type I and type II, and androgen is currently unclear. Thus, in the present study, we made an initial attempt to elucidate the effect of androgen on type I and type II receptor expression in the rat ventral prostate by measuring the levels of messenger RNA (mRNA) and protein at specific time points after castration up to 10 days. Within 3 days after castration, an increase in type II receptor mRNA was observed in the prostate, and the level continued to rise until 7 days postcastration (approximately 8-fold increase). Between days 7-10 postcastration, no significant change in the level of type II receptor mRNA was observed. Testosterone administration immediately after castration abolished the induction of type II receptor mRNA during the same 10-day period. Western blot analysis performed for type II receptor showed a similar result, in that the level of type II receptor protein increased approximately 5-fold by day 10 postcastration. In a similar manner to the expression of type II receptor mRNA, the level of type I receptor mRNA increased steadily until day 7 postcastration (approximately 6-fold increase). Between days 7-10 postcastration, the level of type I receptor mRNA did not change significantly. As with type II receptor mRNA, the induction of type I receptor mRNA was suppressed when testosterone was administered immediately after castration. To localize the expression of TGF beta receptor type II, immunohistochemical studies were performed. The results of these studies demonstrated a preferential localization of type II receptor in the prostatic epithelial cells and an increased staining intensity for the receptor after castration. Taken together, these data indicate that TGF beta signaling receptors, type I and type II, are under negative androgenic regulation at the transcriptional level and that TGF beta may be an important regulator of a stromal-epithelial interaction in the rat ventral prostate.

Genetic change in transforming growth factor beta (TGF-beta) receptor type I gene correlates with insensitivity to TGF-beta 1 in human prostate cancer cells

Transforming growth factor beta 1 (TGF-beta 1), a potential regulator of growth of prostate cancer cells, exerts its effects through interaction with membrane receptors. In the present study, an attempt was made to establish a correlation between TGF-beta 1 sensitivity and TGF-beta receptor expression in three prostate cancer cell lines (PC3, DU145, and LNCaP). In a dose-dependent manner, TGF-beta 1 inhibited the proliferation of PC3 and DU145 cells but not LNCaP cells. Since TGF-beta signals through a heteromeric complex composed of TGF-beta receptors type II and type I, the expression of these receptors was investigated by Western blot analysis and reverse transcriptase-PCR. These studies demonstrated that all three prostate cancer cell lines express type II receptor. In contrast, type I receptor was detected only in the TGF-beta 1-sensitive PC3 and DU145 cells but not in the TGF-beta 1-insensitive LNCaP cells. To investigate the possibility that the undetectable expression of type I receptor in LNCaP cells is due to a change in the respective gene, Southern blot analysis was performed. The result demonstrated that there was a genetic change in type I receptor gene in these cells. Subsequently, when LNCaP cells were transiently transfected with T beta R-I cDNA, sensitivity to TGF-beta 1 was restored. These observations indicate that LNCaP cells contain a defective T beta R-I gene which rendered these cells insensitive to the action of TGF-beta 1.

Xanthoma of the liver in a patient with multiple myeloma associated with hyperlipidemia. A case report

A case of xanthoma of the liver in a 61-year-old Korean woman with multiple myeloma, hyperlipidemia and xanthoma of the skin is described. Microscopically, the liver showed a multiple xanthomatous collection of foamy histiocytes as well as diffuse sinusoidal infiltration of the foam cells. This hepatic accumulation of foam cells seems to be related to hyperlipidemia of the patient. The mechanism of hyperlipidemia in multiple myeloma is discussed.

Clinicopathologic comparison of eroded polypoid hyperplasia and solitary rectal ulcer syndrome

We experienced two unusual cases of tumor-like polypoid lesions involving the rectosigmoid colon. They could not be readily classified into any well known polypoid tumors of the rectosigmoid colon, but appeared to have some similarities to the previously documented "eroded polypoid hyperplasia (EPH)". A collective review of our seven cases of solitary rectal ulcer syndrome (SRUS), which proved to be due to paradoxically over-reactive muscle tone of the puborectalis, was performed, and clinicopathologic comparisons between EPH and SRUS were carried out. They shared histopathologic characteristics such as vascular congestion, crypt hyperplasia, and eroded surface, but they were different from each other in clinical symptoms, location of lesions and gross features. Furthermore, in one EPH case there was an altered much profile which was similar to that seen in SRUS and complete rectal prolapse. Conceivably, the pathological features of both EPH and SRUS were thought to have a possible connection with mucosal prolapse syndrome (MPS). Considering that MPS is a group of diseases encompassing SRUS and the related disorders of the colorectum and the anus, it is speculated that EPH of the rectosigmoid colon might be the proximal analogue of SRUS, a mucosal prolapse of the more distal colon.

A clinicopathological study of Kimura's disease and epithelioid hemangioma

The clinicopathological features of 9 cases of Kimura's disease and 5 cases of epithelioid hemangioma(EH) were reviewed. Patients with Kimura's disease presented with multiple or solitary large tumors occurring in the thigh, arms as well as parotid gland. Histologically, the lesions were characterized by numerous lymphoid follicles with proliferation of post-capillary venules lined by plump endothelium and a marked eosinophilic infiltration. Patients with EH were older than those with Kimura's disease and presented papular nodular lesions, less than 1 cm in size. Microscopically, there was proliferation of blood vessels lined by epithelioid endothelium with infiltration by lymphocytes and eosinophils. Although there may occasionally be clinicopathological overlap between Kimura's disease and EH, we consider that these two disorders can be recognized as separate entities.

Benign proliferative disorders of the breast

Fibrocystic disease of the breast has been generally regarded as a disorder due to either excess hormonal stimulation or an exaggerated proliferative response by hypersensitive breast epithelium. The unique lobular lesion-adenosis- and its variants have been regarded as non-neoplastic and non-preneoplastic glandular hypertrophy and hyperplasia, and have different organoid patterns and origins. We have examined a total of 242 cases previously diagnosed as 'fibrocystic disease' at the Department of Pathology with the purpose of clarifying the variants of adenosis in detail and refining the infinitely large 'fibrocystic disease' classification as non-proliferative fibrocystic change and proliferative disorders, such as epitheliosis and atypical hyperplasia. In this study, 224 cases (92.5%) were nonproliferative disease, mostly adenosis (40.1%), and 18 cases (7.5%) were proliferative disease, which consisted of moderate to florid hyperplasia and epitheliosis.

Large mononuclear cells in seminoma--an immunohistochemical analysis of 21 cases

Twenty-one cases of seminoma (including testicular seminoma, ovarian dysgerminoma and extragonadal germinoma) were reviewed for the cell types responsible for the production of alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG). Histologically the cases included seventeen classical seminomas and 4 anaplastic seminomas. The latter had some mononuclear and multinuclear giant cells. All 4 patients with anaplastic seminoma had elevated levels of serum AFP, and each of these cases contained AFP producing tumor cells identified by immunoperoxidase staining. All seminomas of patients with elevated serum levels of HCG were of the classical type but HCG producing tumor cells could not be identified by immunoperoxidase staining. Immunoreactivity to anti-AFP was found in some large mononuclear cells and anaplastic cells. To explain these results, we propose that the large mononuclear cell is a multipotential cell capable of differentiating into a germ cell, yolk sac and embryo, and that the anaplastic seminoma cells might represent a stage on the continuum of cellular differentiation from the large mononuclear cells to germ cells. The multinuclear giant cell does not appear to be essential for the production of either AFP or HCG in seminoma.