Immunobiologic, cytogenetic and drug response features of a newly established cell line (SCRC-1) from renal small cell carcinoma

PURPOSE

We describe the establishment and preliminary characterization of a cell line designated SCRC-1, which was derived from a primary renal small cell carcinoma.

MATERIALS AND METHODS

Continuous cultures of a primary stage IVa renal small cell carcinoma and a xenograft in nude mice derived therefrom were characterized by immunohistology, electron microscopy, immunofluorescence/flow cytometry, cytogenetic analysis, and an in vitro drug resistance assay.

RESULTS

SCRC-1 cells were reactive with antibodies to NSE, chromogranin-A, bombesin, Bcl-2, CD44s, CD44v6, CD44v7 to 8, vimentin and S100 protein (predominantly beta-subunit), and were unreactive with antibodies to EMA, CD54, EGFR(R1), URO-5, URO-7, URO-8 and URO-10. A similar immunoprofile was also found in both the primary tumor and the xenograft. Cytogenetic analysis revealed the following common clonal aberrations in all 50 metaphases analyzed: 45, XX, t (X;10;18) (p11;p11;q11), -der(18)t(X;10;18), indicating the clonal nature of this neoplasm. SCRC-1 cells showed low drug resistance to cyclophosphamide, doxorubicin, gemcitabine and fluorouracil, intermediate resistance to carmustine and mitomycin-C, and extreme resistance to cisplatin.

CONCLUSION

We have documented the initial characterization of SCRC-1, which may be the first cell line reported to be derived from a primary small cell carcinoma of the kidney. This cell line can be used for further studies uncovering the biology and histogenesis of this rare cancer and delineating differences among small cell carcinomas of the kidney and other histological types.

The role of free to total prostate-specific antigen ratio for prostate cancer in screening patients with total serum levels between 4 and 20 ng/ml

BACKGROUND

We retrospectively tried to determine if the free to total prostate-specific antigen (f/t PSA) ratio could improve the specificity of PSA in prostate cancer screening of patients with total serum levels between 4 and 20 ng/ml.

METHODS

Two hundred ninety-five patients with serum PSA levels from 4 to 20 ng/ml had undergone sextant prostate needle biopsy. Each patient had no prior history of prostate cancer, acute urine retention, or prostatitis. Prebiopsy free PSA values were measured in 155 patients. Total PSA levels were determined with the AxSYM enzyme-linked immunosorbent assay. Free PSA levels were measured with the AxSYM microparticle enzyme immunoassay.

RESULTS

Mean f/t PSA ratios were 0.114+/-0.004 in men of the cancer group and 0.161+/-0.008 in men of the benign group (p<0.002). Based on the analysis of sensitivity and specificity in relation to f/t PSA ratios, use of the 18% cutoff point could detect 89% of cancer cases, and at the same time could avoid 35% of unnecessary prostate biopsies. The areas under the receiver-of-characteristic curve for f/t PSA ratio and total PSA were 0.649 and 0.545, respectively.

CONCLUSION

Serum f/t PSA ratios were significantly lower in patients with prostate cancer than in patients with benign disease. The determination of an appropriate f/t PSA ratio should be based on the generated data such as that demonstrated in this study in order to improve diagnostic accuracy and specificity for patients with equivocal PSA values and to avoid conducting unnecessary prostate biopsies.

Human bladder carcinoma cells with an unusual pattern of in vitro growth: transition from nonproliferative spheroids to active monolayer growth upon interaction with tumor-derived fibroblasts

A new transitional cell carcinoma cell line, BCCA-1, derived from a primary urinary bladder carcinoma, was characterized with respect to the growth patterns of in vitro culture, xenotransplantability in SCID mice and immunophenotypic profile. The most unusual finding was a strong tendency of forming many aggregates (multicell spheroids) in the first few days of flask cultures, followed by the attachment of spheroids to monolayer fibroblasts, which came along from stroma of the same tumor. Unlike those reported tumor spheroids whose peripheral layers contained proliferative cells, BCCA-1 spheroids rarely contained mitotic cells. The three-dimensional architecture of BCCA-1 spheroids drastically changed by the attachment of spheroids to fibroblasts, from which epithelial tumor cells spread; this was accompanied by pseudopodia formation and highly aggressive growth of tumor cells. As the fibroblasts degenerated due to overgrowth, tumor cells started to aggregate by retracting their pseudopods and forming many semi-attached spheroids, which eventually detached from the sheet of degenerated fibroblasts. BCCA-1 produced solid tumors as xenografts in SCID mice by subcutaneous injection with as low as 5 x 10(6) cells, suggesting malignant nature of these cells. Immunostaining revealed the expression of MHC-class I, S100 protein, cytokeratin CK7 and CK20, beta-HCG, CEA, epithelial membrane antigen, Le(y) and folate-binding protein by this tumor. While the biological significance of spheroid formation of this kind by BCCA-1 cells remains unclear, it may represent a protection mechanism, by which TCC cells could sustain their viability under unfavorable culture conditions, but proliferate when the conditions became improved, such as the presence of fibroblasts. Our results point to the importance of tumor-associated stromal fibroblasts in TCC tumor progression. Further mechanistic studies to elucidate the mechanism involved in the stromal cell contact mediated-activation of TCC cells in this model system are warranted.

Renal autotransplantation for ureter stricture and renovascular disorders

BACKGROUND

Renal autotransplantation is an established therapy in cases of renal vascular lesions, tumors of the kidney and ureter, complex ureteral lesions, and kidney trauma. It has been a significant technical innovation, aiding the urologist in his great effort to preserve renal function by conserving renal tissue. We report our experience with autotransplantation in 4 patients. The indications, techniques, and results of renal autotransplantation in relation to our own experience are discussed.

METHODS

The patients included 3 women and one man. The average age of the patients was 35 years old, with a range from 20 to 54 years. One patient had Takayasu's arteritis, the second had Nutcracker syndrome with flank pain and hematuria, the third a complicated long ureter stricture, and the fourth patient a renal artery saccular aneurysm.

RESULTS

The average operation time was 7 hours (4.5 to 8.5 hours), and the cold ischemia time was about 88 minutes (45 to 150 minutes). Three of the autografts resumed normal renal perfusion, and in the fourth patient the renal autograft was lost due to vascular thrombosis.

CONCLUSION

Renal autotransplantation is a feasible method for the surgical treatment of renal and ureteral lesions. To avoid postoperative ureteral sloughing and subsequent urinary fistulas, the ureter can be left intact to preserve the ureter blood supply. However, in the case of a complicated vascular reconstruction procedure, it appears to be appropriate to divide the ureter and have the kidney completely free, thus avoiding back-flow perfusion from the intrinsic and intercommunicating blood supply in the ureteral wall, which may result in vascular thrombosis and subsequent autograft failure.

Enterovesical fistula: experiences with 41 cases in 12 years

BACKGROUND

A retrospective analysis of enterovesical fistula treated at Chang Gung Memorial Hospital was conducted to determine the optimal diagnosis and management of this disease.

METHODS

The records of 41 patients who presented from 1984 to 1996 and had a final diagnosis of enterovesical fistula were retrospectively reviewed. The etiology, symptoms on presentation, diagnostic tools, and modality of treatment were analyzed.

RESULTS

The majority of these cases were associated with malignancy (38, 92.7%), and the others with diverticulitis (2, 4.9%) and iatrogenic causes (1, 2.4%). In those with malignancy, 15 patients (39.5%) were found to have tumor recurrence. The most frequent symptom in enterovesical fistula was fecaluria (58.5%), followed by abdominal pain (22%) and dysuria (14.6%). Diagnostic tools included the barium enema, cystography, and cystoscopy; these methods could identify the fistula in 63.2%, 60%, and 53.8% of the patients, respectively. Methods of management included diversion only (39%), one-stage fistula repair (36.6%), and watchful surveillance (24.4%).

CONCLUSION

Enterovesical fistula should be considered if fecaluria, pneumaturia, or persistent non-specific urinary tract infection present as the initial complaint. A thorough surgery for a possible underlying malignancy is mandatory when confronted with enterovesical fistula, since the incidence of inflammatory bowel disease is low in this area. An abdominal computer tomography (CT) scan, barium enema, and cystogram can be useful diagnostic tools. Treatment of this entity should be individualized according to each patients clinical status.

Characterization of murine Th1 clones specific to egg antigen of Schistosoma japonicum and their interaction with cytokines

T cell clones (B1, B21, B7, A25) specific to the soluble egg antigen (SEA) of Schistosoma japonicum were established from C3H/He mice immunized with SEA. These clones belonged to CD3+, CD4+ and CD8-Th1 cells, showing TCR-gamma delta-, TCR-alpha beta+ and Vbeta10b+. The molecular weights of target antigens recognized by the clones ranged from 51 to 80 kDa. Interleukin-2 (IL-2) and IL-12 could vigorously increase the proliferation response of the T clones to SEA; while IL-10 and transforming growth factor-beta1 (TGF-beta1) strongly inhibited the response. IL-12 activity was detected in the culture supernatant of T clones stimulated with SEA in the presence of APC (antigen presenting cells). This stimulation also upregulated the expression of the IL-12 receptor on the T clones. IL-12 from APC served as a costimulatory factor for the SEA induced proliferation of the T clone cells. Clone B1 was able to induce granuloma formation both in vivo and in vitro. These data provide further insight into the complicated interaction among SEA, T cell and cytokine at a clonal level in S. japonicum infection.

trans-dominant interference with human immunodeficiency virus type 1 replication and transmission in CD4(+) cells by an envelope double mutant

We previously reported that a human immunodeficiency virus type 1 (HIV-1) envelope (Env) mutant with the whole cytoplasmic domain deleted, denoted mutant TC, is able to dominantly interfere with wild-type (wt) virus infectivity. In the present study, the feasibility of developing a dominant negative mutant-based genetic anti-HIV strategy targeting the gp41 cytoplasmic domain was investigated. Mutants TC and 427,TC, a TC derivative with a Trp-to-Ser substitution introduced into residue 427 in the CD4-binding site, and a series of mutants with deletions in the cytoplasmic domain, effectively trans-dominantly interfered with wt Env-mediated viral infectivity, as demonstrated by an env trans-complementation assay. The syncytium formation-defective 427, TC double mutant not only inhibited heterologous LAV and ELI Env-mediated viral infectivity but also interfered with syncytium formation and infectivity mediated by the Env proteins of the two primary isolates 92BR and 92US. Stable HeLa-CD4-LTR-beta-gal clones that harbored Tat-controlled expression cassettes encoding the control DeltaKS, which had a deletion in the env gene, wt, or mutant env gene were generated. Viral transmission mediated by laboratory-adapted T-cell-tropic HXB2 and NL4-3 viruses was greatly reduced in the TC and 427,TC transfectants compared to that observed in the control DeltaKS and wt transfectants. Viral replication caused by HXB2 and NL4-3 viruses and by macrophage-tropic ConB and ADA-GG viruses was delayed or reduced in human CD4(+) T cells transfected with the 427,TC env construct compared to that observed in cells transfected with the control DeltaKS or TC env construct. The lack of significant interference by TC mutant was due neither to the lack of TC env gene integration into host DNA nor to the lack of TC Env expression upon Tat induction. These results indicate that this 427,TC Env double mutant has a role in the development of trans-dominant mutant-based genetic anti-HIV strategies.

Conferral of an antiviral state to CD4+ cells by a zipper motif envelope mutant of the human immunodeficiency virus type 1 transmembrane protein gp41

We showed in a transient coexpression study that a single proline substitution for any of the five conserved leucine or isoleucine residues located in the envelope (Env) transmembrane protein gp41 zipper motif of the human immunodeficiency virus type 1 dominantly interferes with wild-type Env-mediated viral infectivity. In the present study, we intended to explore the feasibility of developing a genetic anti-HIV strategy targeting the zipper motif. Stable HeLa-CD4-LTR-beta-gal clones that harbored silent copies of Tat-regulated expression cassettes encoding the zipper motif Env mutants were first generated. Expression of any of the five Env mutants in transfectants interfered with exogenously expressed homologous HXB2 Env-mediated cytopathic effects. Mutant transfectants 566, 573, and 580 were further examined. Viral transmission mediated by the laboratory-adapted T cell-tropic HXB2 and NL4-3 viruses was greatly reduced in these transfectants compared with that observed in the env-defective control deltaKS and wt env transfectants. Moreover, viral replication mediated by the NL4-3 virus and a macrophage-tropic ADA-GG virus was delayed or reduced in human T cells harboring the mutant 566 or 580 env construct as opposed to those observed in cells harboring the control deltaKS or mutant 573 env construct. The wt and mutant Env proteins formed a hetero-oligomer when they were coexpressed. These results demonstrate that zipper motif Env mutants 566 and 580 confer an anti-HIV state to the host CD4+ cells, which indicates that dominant inhibitory mutants targeting the gp41 zipper motif might function as genetic anti-HIV agents to combat HIV-1 infection.

Partial nephrectomy for incidental primary renal neuroendocrine carcinoma: case report

Here we present an 83-year-old woman who was referred to our hospital and had had left flank pain and oligouria for 3 days. Plain abdominal film and ultrasonography revealed left ureteropelvic junction stone with obstructive uropathy. The serum level of creatinine fell to 3.1 mg/dl from 7.6 mg/dl after ureteral catheter drainage was given 5 days after admission. Then a left pyelolithotomy was performed and a tumor of 2 x 1 x 1 cm over the lower pole of the left kidney was found incidentally. Partial nephrectomy was performed in consideration of her age and poor renal function although the biopsy result showed it to be carcinoma. The final pathological report and immunohistochemical study results proved that it was neuroendocrine carcinoma. To our knowledge, this is the first case of primary renal neuroendocrine carcinoma to be treated using conservative surgery. The clinical course was acceptable, since she had been found to be free of disease during regular follow-up of 2.5 years with the creatinine level of about 2.5 mg/dl.

Dynamic analysis of T-lymphocyte function in relation to hepatopathologic changes and effect of interleukin-12 treatment in mice infected with Schistosoma japonicum

We analyzed the dynamics of splenic T-lymphocyte function in relation to hepatopathologic changes in C3H/Hc mice, experimentally infected with Schistosoma japonicum. Vigorous granuloma formation was observed at 7 wk postinfection. At 10 wk postinfection, granuloma formation entered into the down-modulation stage, as represented by the diminished granuloma size. The Th2 response was activated when eggs appeared in the liver, whereas Th1 responses were depressed and the proliferation of T lymphocytes was decreased. The level of IgG antibodies to the worm and egg antigens rose continually after infection. Interleukin-12 treatment of infected mice inhibited Th2 responses and T-cell proliferation, decreased granuloma formation and fibrosis, but had no effect on the fecundity of the worms. These data suggest that egg deposition is the major factor driving Th2 responses, depressing Th1 cytokine expression as well as T-cell proliferation in S. japonicum-infected mice.

Prognostic factors and strategy of treatment in Fournier's gangrene: a 12-year retrospective study

BACKGROUND

Fournier's gangrene (FG) is a fulminant and fatal infection of the genitalia. However, the clinical course is unpredictable. This study retrospectively analyzed the possible prognostic factors of FG.

METHODS

Data obtained from 57 patients treated for FG from January 1985 through December 1996 were retrospectively analyzed. Possible prognostic factors including age, diagnostic delay, hospital stay, underlying diseases, clinical symptoms, origins, extents, bacteriologic findings, diverting colostomy and mortality rate were all considered in the analysis.

RESULTS

Patients with extensive or localized FG had mortality rates of 31.3% and 16.0%, respectively (p = 0.227). The mortality rates of patients with FG of anorectal, urogenital and non-specific origin were 30.3%, 0% and 40.0%, respectively (p = 0.712). The mortality rates of patients with FG of anorectal origin who received primary or secondary diverting colostomy were 16.7% and 40.0%, respectively. However, the mortality rate of patients with FG of anorectal origin who did not undergo diversion was 29.4%. The mortality rate of patients with FG presenting with septic shock at emergency was 53.8% as compared with 0% in those without septic shock (p < 0.001).

CONCLUSION

Fournier's gangrene is a rapidly progressive and life threatening infection of the genitalia. Age, underlying diseases, origin, extent and fecal diversion can not be regarded as prognostic factors of FG. Early primary diverting colostomy may reduce the mortality rate in those with severe infection of anorectal origin. Presence of septic shock in those with FG is the most important and the only factor related to death.

Mutations in the leucine zipper-like heptad repeat sequence of human immunodeficiency virus type 1 gp41 dominantly interfere with wild-type virus infectivity

It has been previously shown that a proline substitution for any of the conserved leucine or isoleucine residues located in the leucine zipper-like heptad repeat sequence of human immunodeficiency virus type 1 (HIV-1) gp41 renders viruses noninfectious and envelope (Env) protein unable to mediate membrane fusion (S. S.-L. Chen, C.-N. Lee, W.-R. Lee, K. McIntosh, and T.-M. Lee, J. Virol. 67:3615-3619, 1993; S. S.-L. Chen, J. Virol. 68:2002-2010, 1994). To understand whether these variants could act as trans-dominant inhibitory mutants, the ability of these mutants to inhibit wild-type (wt) virus infectivity was examined. Comparable amounts of cell- and virion-associated gag gene products as well as virion-associated gp41 were found in transfection with wt or mutant HIV-1 provirus. Viruses obtained from coexpression of wt provirus with mutant 566 or 580 provirus inhibited more potently the production of infectious virus than did viruses generated from cotransfection of wt provirus with other mutant proviruses. Nevertheless, all viruses produced from mixed transfection showed decreased infectivity compared with that of the wt virus when a multinuclear-activation beta-galactosidase induction assay was performed. The ability of wt Env to induce cytopathic effects was inhibited by coexpression with mutant Env. Coexpression of mutants inhibited the ability of the wt protein to mediate virus-to-cell transmission, as demonstrated by an env trans-complementation assay with a defective HIV-1 proviral vector. These observations indicated that mutant Env, per se, interferes with wt Env function. Moreover, cotransfection of wt and mutant proviruses produced amounts of cell- and virion-associated gag gene products comparable to those produced by transfection of wt provirus. Similar amounts of gp41 were also found in virions generated from wt-mutant cotransfection as well as from wt transfection alone. These results indicated that the inhibitory effect conferred by mutants on the wt virus infectivity does not involve the late steps of Gag protein assembly and budding, but they suggest that the wt and mutant Env proteins form a dysfunctional hetero-oligomer which is impaired in an early step of the virus replication cycle. Our study demonstrates that mutations in the HIV-1 gp41 leucine zipper-like heptad repeat sequence dominantly inhibit infectious virus production.

Adrenal extramedullary hematopoietic tumor in a patient with beta-thalassemia

We report a case of adrenal extramedullary hematopoiesis in a 27-year-old woman with beta-thalassemia. She underwent cholecystectomy for gallstones and splenectomy for splenomegaly at the age of 20 years. In January 1996, she was admitted to our hospital because of a palpable nontender mass in the right subcostal area. Ultrasound, computed tomography, and magnetic resonance imaging disclosed a right suprarenal mass 7.5 x 5.8 cm in size. Surgical exploration and biopsy confirmed the diagnosis of extramedullary hematopoietic (EMH) tumor. The tumor was left in situ. Subsequent follow-up showed no increase in the size of the tumor and no progression of anemia. The patient remained asymptomatic, and no additional EMH tumor developed. Surgery or radiotherapy should be performed only when EMH tumors cause symptoms, such as during spinal cord compression. Adrenal EMH tumors should be considered in thalassemia patients with an adrenal mass, to avoid unnecessary surgical procedures.

Gastric cancer with obstructive uropathy: clinical experience with 17 cases

BACKGROUND

Gastric cancer can spread to either the paraaortic area or pelvis causing ureteral obstruction.

METHOD

Between 1984 and 1996, 17 patients with gastric cancer were proven to have obstructive uropathy (OU). Of these, 12 (70%) had poorly differentiated adenocarcinomas.

RESULTS

The obstructed levels were at the proximal ureter (7 cases), distal ureter (7 cases), and at multiple sites in the ureter (3 cases). The mucosa of the ureter tended to be spared. In 3 cases, OU was the initial presentation. Peritoneal carcinomatosis was noted in all cases. Most cases demonstrated obvious paraaortic lymph node and/or pelvic metastases. Management of ureteral obstruction included percutaneous nephrostomy (PCN) in 8 cases, and cystoscopic placement of a ureteral stent in 9 cases with double-J stents used in 8. Insertion of the double-J stent failed in 1 case initially. Four cases using double-J stents resulted in occlusion within 1 month, of which 3 subsequently were successfully changed to PCN.

CONCLUSION

Gastric cancer with OU can obstruct the ureter at any level. Double-J stents exhibited a high failure rate in these patients necessitating a switch to PCN. We could also choose PCN as the initial procedure to preserve renal function.

Culture medium induced morphological changes of melanoma cells associated with change in sensitivity to lysis by lymphokine-activated killer cells

Three sublines (Clones 1, 2 and 7) of the human melanoma CaCL 73-36 cell line with different cellular morphology, growth patterns, melanin content and surface antigenic profile were maintained in RPMI-1640 medium plus 10% fetal bovine serum (abbreviated as RPMI). Each subline was divided into two groups: one grown in RPMI and the other in Dulbecco's modified Eagle's medium plus 10% fetal bovine serum (abbreviated as DMEM) for 96 h. Phenotypically, Clone 2 expressed Class I and II MHC and ICAM-1 on the surface and in the cytoplasm, while Clones 1 and 7 failed to express these antigens in both the cytoplasm and on the cell surface. Melanotic Clones 1 and 7 cells became even more pigmented, had slower growth rates, and exhibited lower saturation densities when incubated in DMEM than when they were incubated in RPMI. On the other hand, Clone 2 cells maintained in RPMI were grossly amelanotic, contained defective-like melanosomes detected ultrastructurally, and had distinct clusters of microvilli polarly located in most of the cells. Such specialized ultrastructures were not affected by medium conditions. Analysis of sensitivity of the clonal sublines to cytolysis by allogeneic effector cells revealed that in spite of low levels of natural killer (NK) cytotoxicity noted, DMEM produced a 2- to 14-fold increase in sensitivity to NK cells, irrespective of which medium was used. Different levels of lymphokine-activated killer (LAK) cytolytic activity were clearly observed in sublines maintained in RPMI, with Clone 2 being the most sensitive and both Clones 1 and 7 being less sensitive. Cells grown in DMEM exhibited significantly higher levels of sensitivity to LAK cytolysis than cells grown in RPMI as revealed by their differences in lytic units (p < 0.05). This was likely due to the high levels of surface ICAM-1 expression in cells incubated in DMEM vs little expression of this adhesion molecule by cells grown in RPMI. Taken together, these results demonstrate the presence of heterogeneous subpopulations within the CaCL 73-36 melanoma cell line regarding their pigmentary status, antigenic profile, growth pattern and responsiveness to NK/LAK cytolysis. The results also call attention to the importance of utilizing a same medium in short- and long-term cultures of melanomas for biological studies and response evaluations of therapeutic agents such as LAK cells, when multiple cell targets from different patients or multi-metastatic cell lines from individual patients are to be compared. Finally, these melanoma sublines may be valuable for further elucidation of the relationship between MHC expression, and increased sensitivity to LAK cytolysis, and the role of the components of DMEM in the mechanism for the observed induction of cell differentiation and enhanced LAK cytolysis.

Application of cryoablation in the management of prostate cancer

BACKGROUND

Radical prostatectomy is the most common and effective therapy for localized prostate cancer. But in addition to its surgical complications, even highly selected series carry a positive margin rate of 35 to 50%. Radiotherapy is another alternative for prostate cancer, but following radiotherapy there have been high positive biopsies reported. Cryosurgery, defined as in situ freezing and hence, devitalization of neoplastic tissues, has currently raised the interest of urologists in the management of localized prostate cancer or failed radiotherapy.

MATERIAL

Five patients underwent transperineal cryosurgery of prostate in Chang Gung Memorial Hospital. Among them, three cases were stage D, one stage B and another failed radiotherapy of stage C prostate cancer. All patients received hormone therapy too.

RESULTS

PSA declined in 3 patients and biopsies showed intraductal neoplasia. All 5 patients suffered from urine incontinence and one persisted. No mortality has been reported.

CONCLUSION

Cryoablation of the prostate is an alternative for treatment of prostate cancer.

Two Otx proteins generated from multiple transcripts of a single gene in Strongylocentrotus purpuratus

Orthodenticle-related (Otx) proteins are a highly conserved class of homeobox-containing transcription factors found in a wide range of organisms. They function in numerous developmental events, most prominently, anterior head patterning in insects and vertebrates. In the sea urchin, Strongylocentrotus purpuratus, an orthodenticle-related protein called SpOtx is believed to direct the activation of the aboral ectoderm-specific Spec2a gene and more generally the differentiation of aboral ectoderm cells. To learn more about the structure, expression, and function of SpOtx and compare its properties with those of orthologs from other species, we isolated cDNA and genomic clones containing SpOtx sequences. Here, we report that SpOtx exists in two forms (alpha and beta) that are generated by alternative RNA splicing from a single SpOtx gene. SpOtx(alpha) and SpOtx(beta) had identical C-termini and homeoboxes but were entirely different in their N-terminal domains. SpOtx(alpha) mRNAs were transcribed from a single start site and accumulated in all cells during cleavage, but were gradually concentrated in oral ectoderm and vegetal plate territories during gastrulation. In contrast, three distinct SpOtx(beta) mRNAs resulted from two separate transcriptional initiation events, and these transcripts began to accumulate at mesenchyme blastula stage primarily in ectoderm and then later were largely restricted to oral ectoderm and vegetal plate territories. DNA-binding activity for SpOtx(beta) appeared later in development than SpOtx(alpha). Overexpression of SpOtx(alpha) and SpOtx(beta) induced in sea urchin embryos by mRNA injection demonstrated that SpOtx(alpha) was able to repress the accumulation of SpOtx(beta) transcripts, whereas SpOtx(beta) had no effect on the accumulation of SpOtx(alpha) transcripts. These results demonstrate that novel forms of Otx are produced in sea urchins by differential promoter utilization and alternative splicing. It may be that similar regulatory mechanisms lead to diverse forms of Otx in vertebrates.

Effect of IL-12 on granuloma formation induced by injected Schistosoma japonicum eggs

The regulatory functions of IL-12 on granuloma formation by the eggs of S. japonicum in the lungs of BALB/c mice were studied. Mice were injected i.v. with the eggs to induce the pulmonary granuloma. On days 0, 1, 2, 3, 7, 8 after injection, mice were injected i.p. with murine rIL-12 at a dose of 1 microgram day-1 (Group I) or 3 micrograms day-1 (Group II) or with PBS as a control (Group III). On day 10, all mice were sacrificed. The areas of pulmonary granulomas in histological sections were quantitatively measured by image analyser and the levels of mRNA for IL-10, IFN-gamma, IL-12 and IL-5 were assayed by reverse transcriptase PCR (RT-PCR). The results showed that the mean area per granuloma was significantly decreased in Groups I and II as compared with Group III. As for cytokine induction, IL-10- and IFN-gamma-specific bands appeared in Groups I and II, but not in Group III. Bands for IL-5 appeared in all groups, while bands for IL-12 were not detected in any group. It is suggested that IL-12 could inhibit the Th2 dominant granuloma formation induced by the eggs of S. japonicum.