[Examination for indication of systematic biopsy for diagnosis of prostate cancer]

BACKGROUND

Systematic biopsy has been commonly used for detection of prostate cancer. Nevertheless, as this examination occasionally gives patients severe complications it is necessary to give careful consideration for application of this examination. Thus, we analyzed retrospectively 145 cases who underwent transrectal ultrasonography (TRUS) guided systematic biopsy to evaluate the application of systematic biopsy, correlating with the findings of digital rectal examination (DRE), prostate specific antigen (PSA), the findings of transrectal ultrasonography (TRUS) and the results of biopsies.

METHODS

Between May, 1995 and May, 1997, 143 patients who were suspected to have prostate cancer with either of PSA and DRE, and 2 patients who received visual laser ablation of prostate (VLAP), underwent TRUS guided systematic biopsy of prostate. We evaluated diagnostic efficacy of PSA, DRE, TRUS, prostate-volume-specific PSA, and PSA density (PSAD).

RESULTS

Sensitivity, specificity and positive predictive value (P.P.V.) are 78.4%, 62.8% and 53.5% for DRE, 100.0%, 4.4% and 41.8% for PSA, 88.2%, 60.0% and 52.9% for TRUS, 87.8%, 72.1% and 64.2% for prostate-volume-specific PSA, 100.0%, 30.6% and 45.4% for PSAD, respectively. Ten of 69 patients (14.5%) whose PSA levels were 4.0 to 10.0 ng/ml were diagnosed as cancer, and positive for both or either of DRE and TRUS. Twenty-seven who were negative for both of DRE and TRUS were not diagnosed as prostate cancer. Using the combination of prostate-volume-specific PSA, DRE and TRUS, we could eliminate 29 non-cancer men (21.5%) whose PSA level was greater than 4.0 ng/ml from systematic biopsy.

CONCLUSION

On the diagnosis of prostate cancer, the combination of prostate-volume-specific PSA, DRE and TRUS is very useful to exclude unnecessary systematic biopsy, if an urologist could be used to and trained for DRE and TRUS.

Restricted diversification of T-cells in chronic active Epstein-Barr virus infection: potential inclination to T-lymphoproliferative disease

To assess the abnormal T-cell expansion in chronic active Epstein-Barr virus infection (CAEBV), T-cell antigen receptor (TCR) repertoire was analyzed in four patients with the disease. All fulfilled the diagnostic criteria of CAEBV, presenting with fever, hepatosplenomegaly, cytopenia, abnormal high titers of anti EBV-antibodies, and positive EBV genome of unknown cause. Southern blotting probed with EBV-terminal repeats and TCR Cbeta gene indicated clonal expansion of the infected cells in 3 and 2 patients, respectively. The number of CD4+ HLA-DR+ cells appreciably increased in patients 1 (59%) and 2 (24%), who had a coronary aneurysm and central nervous system involvement, respectively. TCR gene expression examined by the inverse polymerase chain reaction methods revealed that Vbeta gene usages were preferential in all patients (Vbeta7 and Vbeta12: patient 1, Vbeta4: patient 2, Vbeta13: patients 3 and 4), compared with those in healthy controls. Valpha18 gene expression was remarkably high in patients 1 and 2. Moreover, Jbeta gene expression was skewing in the reigning Vbeta clones in all patients. Vbeta4-Jbeta1.5 and Vbeta13-Jbeta1.5 genes were clonally expressed in patients 2 and 4, respectively. These results suggest that CAEBV is associated with the restricted diversity of T-cells, which may stem from the sustained expansion of oligoclonal T-cells possibly driven by conventional viral antigens, but not, superantigens. Although the study is limited by the small number of patients, the unbalanced T-cell repertoire might contribute to the evolution of T-lymphoproliferative disease, otherwise, imply the innate defective immunity to EBV in CAEBV patients.

Soluble interleukin-6 (IL-6) receptor with IL-6 stimulates megakaryopoiesis from human CD34(+) cells through glycoprotein (gp)130 signaling

We have recently shown that stimulation of glycoprotein (gp) 130, the membrane-anchored signal transducing receptor component of IL-6, by a complex of human soluble interleukin-6 receptor (sIL-6R) and IL-6 (sIL-6R/IL-6), potently stimulates the ex vivo expansion as well as erythropoiesis of human stem/progenitor cells in the presence of stem cell factor (SCF). Here we show that sIL-6R dose-dependently enhanced the generation of megakaryocytes (Mks) (IIbIIIa-positive cells) from human CD34(+) cells in serum-free suspension culture supplemented with IL-6 and SCF. The sIL-6R/IL-6 complex also synergistically acted with IL-3 and thrombopoietin (TPO) on the generation of Mks from CD34(+) cells, whereas the synergy of IL-6 alone with TPO was barely detectable. Accordingly, the addition of sIL-6R to the combination of SCF + IL-6 also supported a substantial number of Mk colonies from CD34(+) cells in serum-free methylcellulose culture, whereas SCF + IL-6 in the absence of sIL-6R rarely induced Mk colonies. The addition of monoclonal antibodies against gp130 to the suspension and clonal cultures completely abrogated the megakaryopoiesis induced by sIL-6R/IL-6 in the presence of SCF, whereas an anti-TPO antibody did not, indicating that the observed megakaryopoiesis by sIL-6R/IL-6 is a response to gp130 signaling and independent of TPO. Furthermore, human CD34(+) cells were subfractionated into two populations of IL-6R-negative (CD34(+) IL-6R-) and IL-6R-positive (CD34(+) IL-6R+) cells by fluorescence-activated cell sorting. The CD34(+) IL-6R- cells produced a number of Mks as well as Mk colonies in cultures supplemented with sIL-6R/IL-6 or TPO in the presence of SCF. In contrast, CD34(+) IL-6R+ cells generated much less Mks and lacked Mk colony forming activity under the same conditions. Collectively, the present results indicate that most of the human Mk progenitors do not express IL-6R, and that sIL-6R confers the responsiveness of human Mk progenitors to IL-6. Together with the presence of functional sIL-6R in human serum and relative unresponsiveness of human Mk progenitors to IL-6 in vitro, current results suggest that the role of IL-6 may be mainly mediated by sIL-6R, and that the gp130 signaling initiated by the sIL-6R/ IL-6 complex is involved in human megakaryopoiesis in vivo.

Reperfusion of occluded capillary beds in diabetic retinopathy

PURPOSE

To demonstrate the reperfusion of nonperfused capillary beds in diabetic retinopathy.

METHODS

In a retrospective study, we reviewed 292 fluorescein angiograms of 94 eyes of 74 patients (mean age, 52 years; range, 20 to 68 years) with diabetic retinopathy. Fluorescein angiography was performed repeatedly (mean, three times; range, two to eight times) during a mean follow-up period of 2 years (range, 3 months to 12 years). None of the 94 eyes received laser photocoagulation.

RESULTS

Reperfusion of occluded capillary beds was observed in 65 (69%) of 94 eyes. Reperfusion was characterized by recanalization in 22 (34%) of the 65 eyes or by intraretinal neovascularization in 54 (83%) of the 65 eyes. The former took place in small nonperfused areas and the latter in larger nonperfused areas. Reperfusion occurred throughout the entire fundus in six of 94 eyes, resulting in resolution of diabetic retinopathy. Reperfused capillary beds with intraretinal neovascularization left vascular remodeling, which was seen as twisted or kinked abnormal vessels.

CONCLUSIONS

In diabetic retinopathy, occluded capillary beds may be reperfused. Twisted abnormal vessels may represent the reperfusion process through intraretinal neovascularization.

Interferon-gamma and human megakaryopoiesis

Interferon-gamma (IFN-gamma) exhibits various properties including antigrowth activity in neoplastic and normal cells and regulatory roles in immune responses and hematopoiesis, but studies of IFN-gamma effects on human megakaryopoiesis have been inconclusive. Recently we have used serum-free culture of purified CD34+ cells to demonstrate that IFN-gamma stimulates the proliferation of relatively mature megakaryocytic progenitors independently of thrombopoietin. It has been also shown that IFN-gamma stimulates the maturation of megakaryocytes, and has a significant synergism with stem cell factor in human megakaryopoiesis. Further studies are needed to clarify the in vivo effect of IFN-gamma on human megakaryopoiesis and the clinical relevance of IFN-gamma.

Retinal arteriovenous shunt at the arteriovenous crossing

OBJECTIVE

The purpose of the study was to demonstrate that the arteriovenous shunt at the arteriovenous crossing could occur in major retinal vascular diseases other than Takayasu disease.

DESIGN

Clinical review of consecutive case series.

PARTICIPANTS

The authors studied 1885 eyes with retinal vascular diseases such as diabetic retinopathy, branch retinal vein occlusion, central retinal vein occlusion, central retinal artery occlusion, Leber's miliary aneurysms, Eales disease, Behçet disease, and systemic lupus erythematosus retinopathy.

INTERVENTION

Fluorescein fundus angiography using a wide-field fundus camera (60 degrees) was performed.

MAIN OUTCOME MEASURES

Dye transit from artery to vein through sequential angiography.

RESULTS

The arteriovenous shunt at the arteriovenous crossing was found in 8 eyes with proliferative diabetic retinopathy, 27 eyes with branch retinal vein occlusion in the chronic stage, 2 eyes with central retinal vein occlusion, 2 eyes with central retinal artery occlusion, and 2 eyes with miliary aneurysms. The arteriovenous shunt was formed by a direct inflow from artery to vein, showing vasodilation and hyperpermeability, followed by obliteration peripheral to the shunts. The pattern of initial inflow was classified into axial flow and laminar flow, and the inflow became wider and more rapid in the advanced stage.

CONCLUSIONS

These findings indicate that the arteriovenous shunt at the arteriovenous crossing is not a unique phenomenon in Takayasu disease but rather is a basic pattern of retinal vascular reaction pathologic states.

Formation of retinochoroidal collaterals in central retinal vein occlusion

PURPOSE

To demonstrate the drainage routes that compensate the venous congestion in central retinal vein occlusion.

METHODS

Indocyanine green angiography was performed in 13 eyes of 13 patients with central retinal vein occlusion at the involutional stage using a scanning laser ophthalmoscope. The interval between onset of central retinal vein occlusion and indocyanine green angiography ranged from 1.0 to 9.3 years (mean, 3.6 years). Panoramic indocyanine green angiograms that covered the entire choroidal vasculature were produced by composing regional angiograms.

RESULTS

Retinochoroidal collateral routes were found in 10 eyes that had papillary vascular loops. They were not observed in three eyes that did not have the vascular loops. Papillary vascular loops served as the collaterals to connect retinal veins and choroidal veins. The blood in the retinal veins was drained through the papillary vascular loops into the choroidal veins. These choroidal veins were selectively dilated and acted as drainage routes to the vortex veins. Nasal vortex veins served as extraocular exits of the drainage routes in all 10 eyes, and temporal vortex veins served as extraocular exits of the drainage routes in three of the 10 eyes.

CONCLUSIONS

In central retinal vein occlusion with papillary loops, blood in the retinal veins ultimately drained into the vortex veins through the retinochoroidal collaterals.

Chemical synthesis of a novel aromatic amine mutagen isolated from water of the Nishitakase River in Kyoto and a possible route of its formation

Among five mutagenic compounds isolated from water samples, taken at sites below the sewage plants of the Nishitakase River in Kyoto, Japan, the structure of compound I has been determined to be 2-[2-(acetylamino)-4-[bis(2-methoxyethyl)amino]-5-methoxyphenyl]-5-am ino-7-bromo-4-chloro-2H-benzotriazole (PBTA-1). Since this novel aromatic amine mutagen has characteristic substituents in its molecule, it is postulated that the azo dye, 2-[(2-bromo-4, 6-dinitrophenyl)azo]-4-methoxy-5-[bis(2-methoxyethyl)amino]acetoanili de (AZO DYE-1), used as an industrial material, is converted to the corresponding 2-phenylbenzotriazole derivative with a reducing reagent and subsequently to PBTA-1 by chlorination. In fact, AZO DYE-1 changed to the dechlorinated derivative of PBTA-1 (deClPBTA-1) on treatment with sodium hydrosulfite, and this reacted with sodium hypochlorite to produce PBTA-1. Moreover, the presence of deClPBTA-1 was confirmed in a river water sample, along with PBTA-1. PBTA-1 showed potent mutagenic activities in Salmonella typhimurium TA98 and YG1024, inducing 88 000 and 3 000 000 revertants, respectively, per microg, with S9 mix. deClPBTA-1 was also mutagenic, but less potent. From these observations, it is suggested that PBTA-1 is produced from AZO DYE-1 through deClPBTA-1, during industrial processes at dyeing factories and the treatment of wastewater at sewage plants.

Radiation choroidopathy with remodeling of the choroidal venous system

PURPOSE

To describe a case of radiation choroidopathy manifesting drastic remodeling of choroidal drainage routes.

METHOD

Case report. A 34-year-old man who had received radiation treatment for a tumor in the upper eyelid of his right eye 15 years earlier had floating black spots. He was examined ophthalmologically, including with indocyanine green angiography using a scanning laser ophthalmoscope.

RESULTS

The right eye manifested classic features of radiation retinopathy in the superior fundus. Indocyanine green angiography showed vaso-occlusion of choroidal arteries, capillaries, and veins in a wider area than that affected by radiation retinopathy. The superotemporal vortex vein was obliterated, resulting in a remodeling of the choroidal veins in the same quadrant. The blood in this quadrant drained into the inferotemporal vortex vein through collateral venovenous drainage routes.

CONCLUSION

The diagnosis in this eye was radiation retinopathy and radiation choroidopathy. Choroidal vascular lesions were more pronounced and involved a wider area than retinal vascular lesions did. This case illustrates that the choroidal veins may manifest a vast plasticity to remodel the drainage route after obliteration of a major vortex vein.

Synergistic action of Flt3 and gp130 signalings in human hematopoiesis

We recently showed that c-kit signal synergizes with glycoprotein (gp)130 signal mediated by a complex of interleukin (IL)-6 and soluble IL-6 receptor (IL-6/sIL-6R) to stimulate the expansion of human primitive hematopoietic progenitor cells and erythropoietin-independent erythropoiesis. In the present study, we examined the effect of a ligand for Flt3 (FL), whose receptor tyrosine kinase is closely related to c-kit, in combination with IL-6/sIL-6R on human hematopoiesis in vitro. In serum-containing methylcellulose clonal culture of cord blood CD34(+) cells, whereas FL alone stimulated only granulocyte-macrophage (GM) colony formation, erythroid bursts and mixed colonies in addition to GM colonies were induced by FL with IL-6/sIL-6R, but not IL-6/sIL-6R alone. In suspension culture, CD34(+) cells generated a small number of myeloid cells in the presence of FL or IL-6/sIL-6R alone. However, the addition of IL-6/sIL-6R to the culture with FL induced the generation of a significant number of erythroid cells and megakaryocytes in addition to myeloid cells. The combination of FL and IL-6/sIL-6R also induced a remarkable expansion of GM colony- and erythroid burst-forming cells and multipotential progenitors, although FL or IL-6/sIL-6R alone induced the generation of only a small number of progenitors for GM colonies. The synergistic effects of FL and IL-6/sIL-6R were confirmed in serum-free clonal and suspension cultures. In addition, the addition of anti-human gp130 monoclonal antibodies abrogated the synergistic action. These results indicate that Flt3 signal, as well as c-kit signal, synergizes with gp130 signal to stimulate human myelopoiesis, erythropoiesis and megakaryopoiesis, and the expansion of primitive multipotential hematopoietic progenitor cells.

Thrombopoietin-independent effect of interferon-gamma on the proliferation of human megakaryocyte progenitors

Flow cytometric study revealed that almost all CD34+ cells in human umbilical cord blood expressed interferon-gamma receptor (IFN-gammaR). To clarify the precise functional roles of IFN-gammaR in human CD34+ cells, we examined the effect of IFN-gamma alone and in combination with various cytokines on the growth of haemopoietic progenitor cells in CD34+ cells using a serum-free clonal culture. Surprisingly, IFN-gamma alone supported only megakaryocyte (MK) colonies in a dose-dependent manner with a plateau level at 1000 U/ml of IFN-gamma. IFN-gamma at 1000 U/ml induced 10 +/- 1.2 MK colonies from 1 x 10(3) CD34+ cells, whereas thrombopoietin (TPO), interleukin (IL)-3, stem cell factor (SCF) or IL-6 alone induced 22 +/- 4.0, 22 +/- 4.2, 4 +/- 0.6 and 0 MK colonies, respectively. The addition of anti-IFN-gamma monoclonal antibody (mAb) to the IFN-gamma culture completely abrogated MK colony formation, whereas the mAb had no effect on TPO-dependent production of MK colonies. In contrast, although anti-TPO polyclonal Ab almost completely blocked TPO-dependent MK colony formation, it failed to inhibit the generation of MK colonies induced by IFN-gamma, suggesting that the observed effect of IFN-gamma on the proliferation of human MK progenitor cells is independent of TPO. The addition of IFN-gamma to culture with TPO or SCF significantly augmented the development of MK colonies, whereas it did not affect IL-3-dependent MK colony formation. Additionally, IFN-gamma induced the increase of DNA content of cultured glycoprotein IIb/IIIa-positive megakaryocytes. These results suggest that IFN-gamma may have regulatory roles in human megakaryocytopoiesis.

Thrombopoietin alone stimulates the early proliferation and survival of human erythroid, myeloid and multipotential progenitors in serum-free culture

We examined the effects of recombinant human thrombopoietin (TPO, c-Mpl ligand) on the proliferation and differentiation of human haemopoietic progenitors other than megakaryocytic progenitors using serum-free cultures. TPO alone supported the generation of not only megakaryocytic (MK) but also blast cell (blast) colonies from cord blood CD34+ cells. Delayed addition of a cytokine cocktail (cytokines; interleukin (IL)-3, IL-6, stem cell factor, erythropoietin, granulocyte-macrophage colony-stimulating factor, and TPO) to cultures with TPO alone on day 7 induced various colonies including granulocyte-macrophage (GM) colonies, erythroid bursts (E), granulocyte-erythrocyte-macrophage-megakaryocyte (GEMM) colonies. Replating experiments of blast colonies supported by TPO alone for culture with cytokines revealed that approximately 60% of the blast colonies contained various haemopoietic progenitors. Single cell cultures of clone-sorted CD34+ cells indicated that TPO supported the early proliferation and/or survival of both primitive and committed haemopoietic progenitors. In serum-free suspension cultures, TPO alone significantly stimulated the production of progenitors for MK, GM, E and GEMM colonies as well as long-term culture-initiating cells. These effects were completely abrogated by anti-TPO antibody. These results suggest that TPO is an important cytokine in the early proliferation of human primitive as well as committed haemopoietic progenitors, and in the ex vivo manipulation of human haemopoietic progenitors.

Effects and serum levels of thrombopoietin in a case of chronic thrombocytopenia with achondroplasia

Thrombopoietin (TPO), produced mainly in the liver, is a major regulator of platelet production. Serum TPO levels are generally increased in thrombocytopenia. We report a case of a 12-year-old boy with chronic severe thrombocytopenia, achondroplasia and nephritis. Severe chronic thrombocytopenia was found at 9 months of age. It was resistant to any treatment. Studies on megakaryocytic colonies in vitro revealed that the marrow cells responded well to TPO and no plasma inhibitor was found. Although hepatic function test results were normal, serum TPO levels in the patient (0.94 fmol/ml) were consistent with those in age-matched children (0.49-1.75 fmol/ml). Chronic thrombocytopenia requires individual evaluation before clinical trials with TPO.

Hypoxia, but not reoxygenation, induces interleukin 6 gene expression through NF-kappa B activation

Interleukin (IL) 6 is one of major mediators of inflammation, and IL-6 gene activation during hypoxia/reoxygenation has been implicated in the pathogenesis of ischemia/reperfusion injury. However, molecular events involved in IL-6 gene expression during hypoxia/reoxygenation remain to be identified. We have previously shown that NF-kappa B plays an essential and indispensable role in the transcriptional activation of the IL-6 gene induced by various stimuli, including IL-1 and tumor necrosis factor-alpha. We show here that hypoxia, but not reoxygenation, induces the activation of NF-kappa B through the degradation of a major inhibitor of NF-kappa B, I kappa B alpha. This hypoxia-induced NF-kappa B activation resulted in the kappa B-dependent transcriptional activation of the IL-6 gene. Interestingly, the time course of hypoxia-induced NF-kappa B activation was rather slow as compared with those of NF-kappa B activation induced by other stimuli, such as IL-1: a significant NF-kappa B activation was not observed before 1 hr of hypoxia treatment and persisted for up to 7 hr of hypoxia treatment. However, hypoxia-induced NF-kappa B activation was not inhibited by cycloheximide, which indicates that hypoxia directly triggers NF-kappa B activation. Furthermore, while hypoxia is unlikely to generate reactive oxygen intermediates, pretreatment of cells with antioxidants such as N-acetyl cysteine and alpha-tocopherol inhibited NF-kappa B activation induced by hypoxia. Thus, we discuss possible implications of these results for a postulated role of reactive oxygen intermediates in NF-kappa B activation.

Defective response to thrombopoietin and impaired expression of c-mpl mRNA of bone marrow cells in congenital amegakaryocytic thrombocytopenia

Congenital amegakaryocytic thrombocytopenia (CAMT) is an uncommon disorder in newborns and infants, characterized by isolated thrombocytopenia and megakaryocytopenia in the first year without physical anomalies. The defect of thrombopoiesis is not well understood. Recently, thrombopoietin (TPO), the ligand for the c-mpl receptor, was cloned. Accumulating evidence from in vitro and in vivo studies indicate that TPO plays a key role in the regulation of megakaryocytopoiesis. In this study we examined the effect of TPO on megakaryocyte colony formation from a patient with CAMT using a plasma-containing methylcellulose clonal culture. The in vitro results demonstrated a defective response to TPO in megakaryocyte colony formation from bone marrow mononuclear cells (MNC) of the patient. although interleukin-3 (IL-3) but not stem cell factor (SCF) induced only a small number of megakaryocyte colonies. These findings indicated that thrombocytopenia in CAMT could not be corrected by administration of TPO in vitro. Additionally, clonal cultures containing SCF, IL-3, IL-6 and erythropoietin showed decreased numbers of erythroid and myelocytic progenitors in the bone marrow of the patient. The serum TPO level measured by enzyme-linked immunosorbent assay was significantly higher than that in healthy controls. By PCR, marrow MNC from healthy children and from a patient with essential thrombocytosis expressed c-mpl mRNA, whereas no c-mpl mRNA was detected in marrow MNC from the patient with CAMT. There was no difference in the CD34 expression and c-kit mRNA between the CAMT patient and healthy children. The results of this study suggest that the pathophysiology in CAMT may be a defective response to TPO in haemopoietic cells through impaired expression of c-mpl mRNA.

Analysis of interleukin 6 receptor and gp130 expressions and proliferative capability of human CD34+ cells

We recently demonstrated that stimulation of gp130 by a combination of soluble interleukin 6 receptor (sIL-6R) and IL-6 but not IL-6 alone significantly stimulates the ex vivo expansion of primitive hematopoietic progenitors and the generation of erythroid cells from human CD34+ cells in the presence of stem cell factor (SCF). Here, we show that gp130 is found low positively on most CD34+ cells, whereas IL-6R is expressed on only 30-50% of these cells. Although most of the colonies generated from FACS-sorted CD34+IL-6R+ cells were granulocyte/macrophage (GM) colonies, CD34+IL-6R- cells gave rise to various types of colonies, including erythroid bursts, GM, megakaryocytes, and mixed colonies in methylcellulose culture with a combination of IL-6, sIL-6R, and SCF. Similar results were obtained in culture supplemented with a combination of IL-3, IL-6, SCF, granulocyte colony-stimulating factor, erythropoietin, and thrombopoietin. A limiting dilution analysis of long-term culture-initiating cells (LTC-IC) showed that the CD34+IL-6R- cells contained a larger number of LTC-IC than did the CD34+IL-6R+ cells. In a serum-free suspension of CD34+IL-6R- cells, the addition of sIL-6R to the combination of IL-6 and SCF dramatically increased the total and multipotential progenitors, whereas CD34+IL-6R+ cells failed to do so under the same conditions. These results indicate that most of the erythroid, megakaryocytic, and primitive human hematopoietic progenitors are included in the IL-6R- populations, and the activation of gp130 on these progenitors can be achieved by a complex of IL-6-sIL-6R, but not by IL-6 alone. The present culture system using IL-6, sIL-6R, and SCF may provide a novel approach for ex vivo expansion of human primitive hematopoietic progenitors.

[Choroidal vascular lesions in serous retinal detachment viewed with indocyanine green angiography]

In serous retinal detachment due to damaged retinal pigment epithelium (RPE), fluorescein angiography shows dye leakage into the subretinal space from the choroid. We performed indocyanine green (ICG) angiography in 110 eyes with serous retinal detachment comprising 71 eyes with central serous chorioretinopathy (CSC), 19 with bullous retinal detachment, 18 with Harada's disease, and 2 with toxemia of pregnancy. Choroidal tissue staining was present around the site of subretinal leakage in late-phase ICG angiograms from 63 eyes with CSC and 18 with bullous retinal detachment. ICG angiography also showed leakage from choroidal vessels in 16 eyes with Harada's disease and 2 with toxemia of pregnancy. As a common feature, ICG angiography showed choroidal vascular hyperpermeability in various types of serous retinal detachment. Choroidal circulation was delayed in Harada's disease and toxemia of pregnancy. Choroidal hypoperfusion and hyperpermeability of choroidal vessels probably contribute to the damage of RPE, and choroidal vascular hyperpermeability probably provides fluid pressure to move fluid into the subretinal space from the choroid.

Role of glycoprotein 130 and c-Kit signaling in proliferation and differentiation of human hematopoietic progenitor cells

Glycoprotein (gp) 130, a receptor component for interleukin 6 (IL-6), can associate with a soluble IL-6 receptor (sIL-6R)-IL-6 complex. To examine the role of gp130 signaling in human hematopoietic progenitor-cell proliferation and differentiation, we studied the effects of the sIL-6R-IL-6 complex in combination with other cytokines on human CD34+ cells in clonal and suspension cultures. The sIL-6R-IL-6 complex, but not sIL-6R or IL-6 alone, in the presence of stem-cell factor (SCF) produced dramatic increases in the populations of various cell lineages, including erythroid cells and various hematopoietic progenitors, in suspension culture. Significant numbers of colonies of (particularly) multilineage and blast cells were generated in methylcellulose culture supplemented with a combination of sIL-6R-IL-6 complex and SCF. Addition of anti-gp130 monoclonal antibodies (MAbs) and anti-IL-6R MAbs to the above-mentioned cultures dose-dependently inhibited the generation of cells of various lineages and of progenitor cells in suspension culture and completely blocked multilineage colony production in methylcellulose culture; an anti-erythropoietin antibody did not cause inhibition. These findings demonstrate that both proliferation and differentiation of hematopoietic progenitor cells can be induced through gp130 and c-Kit signaling, indicating that progenitor cells are responsive to the sIL-6R-IL-6 complex, even though they do not express IL-6R. Together with previous studies showing that detectable levels of sIL-6R, IL-6, and SCF are present in human serum, these results suggest that gp130 signaling may play an important role in human hematopoiesis in vivo.

Immunosuppressant FK506 induces interleukin-6 production through the activation of transcription factor nuclear factor (NF)-kappa(B). Implications for FK506 nephropathy

FK506 is a powerful immunosuppressive drug currently in use that inhibits the activation of several transcription factors (nuclear factor (NF)-AT and NF-kappaB) critical for T cell activation. We show here that, contrary to the situation in T cells, FK506 activates transcription factor NF-kappaB in nonlymphoid cells such as fibroblasts and renal mesangial cells. We further show that FK506 induces NF-kappaB-regulated IL-6 production in vitro and in vivo, in particular in kidney. IL-6 has been shown previously to produce renal abnormalities in vivo, such as mesangioproliferative glomerulonephritis. Similar renal abnormalities were also observed in FK506-treated animals. These results thus suggest a causal relationship between FK506-induced NF-kappaB activation/IL-6 production and some of FK506-induced renal abnormalities.

Outbreak of acute glomerulonephritis in children: observed association with the T1 subtype of group A streptococcal infection in northern Kyushu, Japan

Group A streptococcal infection is associated with the occurrence of acute glomerulonephritis (AGN) and rheumatic fever (RF). A surveillance study in the Saga area, in northern Kyushu, Japan, showed a small variation in the reported number of group A streptococcal infections in the period 1988-94. However, of the AGN cases reported in this period, more than half were observed in 1992. In order to examine whether some change had occurred in the serotype distribution of Streptococcus pyogenes during the period, patients in the Saga area diagnosed as having group A streptococcal infection and patients with AGN or RF were analyzed. Serological T-typing of S. pyogenes was carried out for patients with group A streptococcal infections, and the association between the occurrence of AGN or RF and the distribution of each different T subtype was analyzed. M-typing of S. pyogenes was also carried out and the correlation between T and M types was examined. From 1988 to 1994, the annual number of patients with group A streptococcal infections in the Saga area showed a small variation, range 65-100 patients/year. Of the 42 patients with AGN and three with RF observed in this period, 27 with AGN (64%) and one with RF (33.3%) were detected in 1992. Only the T1 subtype increased in 1992; the other T subtypes showed little variation in incidence. The number of patients with the T1 subtype was significantly correlated with the occurrence of AGN by regression analysis (P < 0.01). Of the 170 subjects tested for both T and M subtypes, 44 of the 45 T1-typed subjects had the M1 protein. Our epidemiological study suggested that the T1 subtype of streptococcal infection was associated with an outbreak of AGN in 1992 in the Saga area.