Local and Systemic Liberation of Proinflammatory Cytokines in Ulcerative Colitis

Determination of plasma and tissue cytokinelevels in inflammatory bowel disease have frequentlyresulted in conflicting data. In the present study wedetermined in patients with ulcerative colitis (UC), the levels of the proinflammatory cytokinesinterleukin (IL)-1, IL-6, interferon(IFN)-, and tumor-necrosis factor (TNF)-liberated by peripheral blood mononuclear cells (PBMC)and lamina propria mononuclear cells (LPMC) after 48-hrculture with pokeweed mitogen (PWM). IL-1, IL-6,IFN- and TNF- in the supernatant weredetected by ELISA. Results show low basal levels ofIL-1 secretion by PBMC and LPMC, and a considerableincrease after mitogen stimulation. Basal IL-6production by PBMC was higher in UC patients than incontrols [2029 pg/ml, CI₉ (–165 to4223) vs 572 pg/ml (–383 to 1527) respectively, P = 0.05] and also afterPWM activation [14,995 pg/ml (7759 -22230) vs 6598 pg/ml(3240-9956), respectively, P = 0.05]. In LPMC, nodifferences in IL-6 secretion were observed. TNF- in activated PBMC of patients with UC was notsignificantly increased in relation to control (P =0.09). No constitutive secretion of IFN- wasobserved in mononuclear cells. IFN- levelssecreted by activated LPMC were lower in patients withUC than in controls [1571 pg/ml (–108 to 3251) vs7953 pg/ml (3851-12,055), respectively, P = 0.03]. Theseresults suggest that IL-6, IL-1, and TNF- participate as mediators in the inflammatoryphenomena observed in UC. Further studies are necessaryto evaluate the role of IFN- in thiscondition.     

Serum cytokines in patients with rheumatoid arthritis

Serum cytokines such as interleukin 1 (IL-1), interferon (IFN-), and tumor necrosis factor (TNF) were measured in 40 patients with rheumatoid arthritis (RA). In the 40 patients studied, serum IL-1 was detected in 5 patients, IFN- in 10 patients, and TNF in 20 patients. The IL-1-positive group showed increased values of activity indices compared to the IL-1-negative group. Values of serum IFN- correlated well with the number of peripheral blood lymphocytes and CD3⁺ cells and with the percentage of CD3⁺ CD26⁺ cells. Values of serum TNF correlated positively with the number of peripheral blood monocytes and the percentage of CD3⁺ HLA-DR⁺ and CD3⁺ CD25⁺ cells. These results indicated that serum IL-1 in RA patients reflects the activity of RA, while the serum IFN- and TNF in RA patients may be related to circulating activated lymphocytes and monocytes, respectively.     

Characterization of an acute T lymphoblastic leukemia expressing the γ/δ T-cell receptor

Summary Leukemic cells of a 20 year old patient, suffering from acute lymphoblastic leukemia, were characterized by surface marker and functional analysis. A significant cell population within this type of leukemia expresses concomitantly the CD4 and CD8 antigen on the same cell and might represent a new differentiation stage of T-cells with the / receptor. The leukemic cells show a distinct pattern of growth response to mitogens and lymphokines, which might correlate to their differentiation stage. Moreover, a natural killer-like activity can be induced in these cells by IL-2.Abbreviations FITC fluorescein isothiocyanate - PE phycoerythrin - IL-2 interleukin 2; - / TCR gamma/delta T cell receptor - NK natural killer - PBL peripheral blood lymphocytes - T-ALL acute T lymphoblastic leukemia - ConA concanavalin A - PMA phorbol myristate acetate - BM bone marrow - IL-2R IL-2 receptor - TdT terminal deoxynucleotidyl transferase Supported by the Deutsche Forschungsgemeinschaft (DFG Wi-728/3-1)     

Pharmacological evidence for beta3 adrenoceptors in the control of rat gastric acid secretion

The effect of the ₃-adrenoceptor agonist BRL37344 on gastric acid secretion evoked by different secretory stimuli was investigated in anaesthetized rats with lumen-perfused stomachs in comparison with the ₂-adrenoceptor agonist clenbuterol. Intravenous injections of BRL37344 (1–10 mol/kg) and clenbuterol (0.01–1 mol/kg) dose-dependently reduced 2-deoxy-D-glucose-induced acid secretion, with BRL37344 about forty times less potent than clenbuterol. BRL37344 (0.1–3 mol/kg) inhibited pentagastrin-induced acid output, whereas clenbuterol was effective only at high doses (10–100 mol/kg). The inhibitory effect of BRL37344 on pentagastrin-induced acid secretion was not modified by the nonselective –adrenoceptor antagonist propranolol, but it was prevented by bupranolol, a ₃-adrenoceptor antagonist. Furthermore, neither BRL37344 (10 mol/kg) nor clenbuterol (100 mol/kg) modified the acid secretion induced by histamine. These data suggest that ₃ adrenoceptors have an inhibitory role in the control of rat gastric acid secretion induced by indirect stimuli.     

γ/δ Receptor-expressing T-cell clones from a cutaneous T-cell lymphoma suppress hematopoiesis

Summary Recently we described a cutaneous T-cell lymphoma expressing the / T-cell receptor [5]. The patient suffering from this lymphoma showed low numbers of myeloid and T cells in peripheral blood, while B and NK cells were relatively increased. In vitro culture of the patient's bone marrow (BM) cells revealed a significant suppression of myeloid/monocyte colony formation (GM-CFU) compared with normal controls. This was not due to infiltration of the BM with lymphoma cells. We speculated that a soluble factor either secreted or induced by the lymphoma cells might be responsible for the marked suppression of hematopoiesis in this patient. From a skin biopsy with infiltrating / T-lymphoma cells we established T-cell clones bearing the / T-cell receptor and resembling the phenotype of the lymphoma cells. The supernatant (SN) of these / T-cell clones reduced the number of colonies in a CFU-GM assay (using normal control BM) in comparison to SN of / T-cell clones established from the same biopsy. This suppression was seen mainly on day 7 of culture and was not neutralized by the addition of placenta-CM. The main mediator of this suppression seems to be IFN-,since it was detectable in high amounts in the SN of these / T-cell tumor clones as well as in the serum of the patient. In addition, anti-IFN- antibodies can reverse the T-cell SN-mediated suppression of CFU-GM. We conclude that high serum levels of interferon-, which is secreted in high amounts from / T-cells grown from a biopsy of a cutaneous lymphoma, can suppress hematopoiesis.Abbreviations TCR T-cell receptor - IFN- interferon- - SN supernatant - placenta CM placenta conditioned medium - BM bone marrow - CFU-GM myeloid/monocyte colony formation - NK cells natural killer cells - Ab antibody M. Wilhelm was supported by theDeutsche Forschungsgemeinschaft (DFG Wi 728-2)     

Detection of anti-bovine β2-glycoprotein I antibody in sera from patients with antiphospholipid syndrome

We studied and characterized anti-bovine ₂ I antibodies (aB₂-GPI) in sera from patients with antiphospholipid syndrome (APS) by ELISA. Bovine ₂-glycoprotein I ₂-GPI was purified by heparin affinity and DEAE ion-exchange chromatography, and identified on immunoblots using a monoclonal antibody against human ₂-GPI and by amino acid sequence analysis. aB₂-GPI levels in the sera from 36 APS patients were measured by ELISA using purified bovine ₂-GPI as an antigen. The mean±standard deviation level of aB₂-GPI was 17.4±22.0 units in the 58% of APS patients who were positive. There was a significant correlation (P=0.003) between aB₂-GPI and anticardiolipin antibody (aCL) levels. aB₂-GPI from the sera of patients with APS was inhibited by bovine ₂-GPI itself. Purified IgG from the sera of patients with APS showed that bovine ₂-GPI was capable of acting as a cofactor for aCL. Purified bovine ₂-GPI was useful antigen for conventional ELISA. aB₂-GPI may contribute to the further development of aCL analysis and to the understanding of the pathogenesis of APS.     

Differences of cellular composition and adhesion molecule expression in “leukemic” as compared with “normal” human long-term bone marrow cultures

Summary Human long-term bone marrow cultures (HLTBMCs) were established with bone marrow samples collected from 15 patients with acute myeloid leukemia (AML) and compared with HLTBMCs from eight healthy volunteers. During 6 weeks of culture, the cellular composition of HLTBMCs was quantitatively studied. The cells of the HLTBMCs were divided into three main categories: fibroblasts, macrophages, and other cells (endothelial cells, hematopoietic cells and undefined cells). HLTBMCs derived from healthy volunteers demonstrated a very consistent development. The number of fibroblasts increased during culture and the number of macrophages decreased, resulting in a steady state after 3 weeks of culture. In contrast, HLTBMCs derived from patients with AML showed a strikingly different pattern of irregular development and a steady state was not reached under our conditions. The APAAP technique was used to demonstrate expression of adhesion molecules. VLA2, VLA5, VLA6, LFA1, Mac1, p150/95, ₂-chain, HCAM, ICAM1, NCAM, and VCAM1 were more expressed on normal as compared with leukemic bone marrow stromal cells, although this reached significance only for ₂-chain and NCAM. VLA1, 3, and 4 were expressed in a higher percentage on leukemic stroma (not significant). More expression was seen on normal as opposed to leukemic macrophages for the adhesion molecules tested, except for VLA5. The differences reached significance for the majority of molecules tested. It is concluded that striking differences exist in cellular composition and adhesion molecule expression between HLTBMCs from healthy individuals and those from patients with AML. This may have an impact on the pathogenesis of AML.     

On the pathogenesis of preleukemic myelodysplastic syndromes

Summary After a single pulse dose of DMBA, rats develop bone-marrow hypoplasia, which is almost compensated for by regeneration after 16 weeks. Subsequently, dysplastic signs of hemopoiesis appear in all experimental animals as massive extrusion of normoblasts into the peripheral blood, red-cell anisoand poikilocytosis, nuclear deformities, atypical mitoses, and PAS-positivity, as well as megaloblastoid maturation dissociation of erythroblasts and nuclear and granulation anomalies of neutrophilic granulocytes and monocytes, comparable to human pseudo-Pelger cells and paraneutrophils. At the time of death (112-497 days after DMBA pulse) experimental animals showed hyperplastic bone marrow with increased granulopoietic/erythropoietic ratios and an augmented, mainly erythropoietic, hemopoiesis in the spleen, with splenomegaly in six rats. Splenic hemopoiesis is accompanied by white pulp atrophia. The cause of death was septicopyemia in three rats, anemia in three, and bleeding in one rat. None of the animals developed a leukemic blast phase. Myelodysplastic changes in this experiment are the same as have been shown to precede leukemia in rats treated with five DMBA pulses (Fohlmeister et al. 1981). Possible relations of myelodysplasia and leukemia are discussed.Supported by Deutsche Forschungsgemeinschaft (DFG)     

Regulation of the release of tumour necrosis factor (TNF)α and soluble TNF Receptor by γ irradiation and interferon γ in Ewing's sarcoma/peripheral primitive neuroectodermal tumour cells

This study analyses the production of tumour necrosis factor (TNF) and soluble TNF receptor (sTNF-R) before and after exposure to irradiation and interferon (IFN) in 12 cell lines derived from Ewing's sarcoma (ES)/peripheral primitive neuroectodermal tumours (pPNET). Supernatants from ES/pPNET cell cultures were tested in a TNF-specific amplified enzyme-linked immunosorbent assay (ELISA), a bioassay, and sTNF-R_p55 and sTNF-R_p75 ELISA. The tumour cell lines released minimal amounts of TNF, prominent amounts of sTNF-R_p55 (7/12 cell lines) and no sTNF-R_p75. Exposure to irradiation (5 Gy) either induced (3/12) cell lines) or up-regulated (3/12 cell lines) TNF release without changing sTNF-R_p55 and sTNF-R_p75 levels. Priming of cultures with recombinant human IFN (rhIFN) markedly enhanced TNF secretion in the radiation-responsive cell lines and had no influence on sTNF-R_p55 and sTNF-R_p75 levels. rhIFN affected the magnitude rather than the sensitivity of the radiation response. The TNF secreted was bioactive, as shown by its cytotoxic effect of WEHI-164 cells, and neutralization of its activity by anti-TNF monoclonal antibody. Herbimycin A (a tyrosine-specific protein kinase inhibitor) but not calphostin C (a protein kinase C inhibitor), H89 (a protein kinase A inhibitor), AACOCF3 (a specific inhibitor of phospholipase A₂) and MK-886 (a specific inhibitor of 5-lipoxygenase) abrogated -irradiation-stimulated TNF release. The antioxidantsN-acetylcysteine, nordihydroguaiaretic acid and mepacrine dose-dependently inhibited -irradiation-mediated TNF production. Collectively our findings indicate that IFN priming potentiates the secretion of bioactive TNF by ES/pPNET cells in response to irradiation without affecting sTNF-R release. The data suggest a requirement for protein tyrosine kinase activity and a role for reactive oxygen species in the -irradiation-mediated intracellular signalling pathway leading to TNF production.     

Entwicklung neuer Antiöstrogene vom Typ des 3,3′-Dihydroxy-α,β-diäthylstilbens und ihre Prüfung am DMBA-induzierten,hormonabhängigen Mammacarcinom der SD-Ratte

Zusammenfassung Die Verlagerung der phenolischen OH-Gruppen des Diäthylstilböstrols in die 3,3-position (trans-3,3-Dihydroxy-,-diäthylstilben, Verb. Nr. III) führt unter Erhaltung der Rezeptoraffinität zu einer starken Abnhme der östrogenen Wirkung. III hemmt in vitro die östradiol-Rezeptor-Wechselbeziehung kompetitiv und antagonisiert in vivo bei der Maus die uterotrope Wirkung des Östrons. In Versuchen am DMBA-induzierten, hormonabhängigen Mammacarcinom der Ratte kommt es, unter III-Einwirkung dosisabhägig zu einer starken Abnahme von Tumorgröße und-zahl, die durch die antiöstrogenen Eigenschaften von III bedingt, ist. Der Austausch der ,-ständigen Äthylreste in III durch andere Alkylketten führt zu keiner weiteren, Steigerung der antiöstrogenen und tumorhemmenden, Wirkung.

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Abkürzungen trans-4,4-DES trans-4,4-Dihydroxy-,-diäthylstilben (Diäthylstilböstrol DAB 7) - I trans-3,3-Dihydroxy-,-dimethylstilben - II cis-3,3-Dihydroxy-,-diäthylstilben - III trans-3,3-Dihydroxy-,-diäthylstilben - IV trans-3,3-Dihydroxy-,-di-n-propylstilben - V trans-3,3-Dihydroxy-,-di-n-butylstilben - VI trans-2,2-Dihydroxy-,-diäthylstilben - DCC Dextran Coated, Charcoal - DMBA 7,12-Dimethylbenz-[a]-anthracen - TRIS Tris-(hydroxymethyl)-aminomethan - EDTA Äthylendiamintetraessigsäure - E2 Östradiol - ³H-E2 Östradiol [2,4,6,7-³H]; 90–115 Ci/mmol (New England Nuclear, Dreieichenhain/Frankfurt) - PPO 2,5-Diphenyloxazol - Dimethyl-POPOP p-Bis-2-(4-methyl-5-phenyl-oxazoyl)-benzol - K _d Dissoziationskonstante des Östradiol-Rezeptor-Komplexes - K _i Dissoziationskonstante des Inhibitor-Rezeptor-Komplexes - SDS Natriumdodecylsulfat - TCA Trichloressigsäure Der Deutschen Forschungsgemeinschaft, und dem Verband der Chemischen Industrie-Fonds der Chemischen Industrie — danken wir für die Förderung dieser UntersuchungenFrau G. Braun und Frau J. Garamvölgy danken wir für ihre wertvolle MitarbeitEin Teil der Untersuchungen wurde im Institut für Pharmazie, und Lebensmittelchemie der Universität München durchgeführtHerrn Prof. Dr. Heinrich Thies zum 75. Geburtstag gewidmet     

Cooperative effects of gamma-interferon and 1α, 25-dihydroxyvitamin D3 on in vitro differentiation of the blast cells of RAEB and RAEB-T

Summary We added recombinant human gammainterferon (-IFN) and 1 , 25-dihydroxyvitamin D₃ (1 , 25 (OH)₂D₃) to the bone marrow cells from six patients with RAEB or RAEB-T in liquid suspension cultures. After cultivation for 7 to 9 days, numerical, morphological and functional changes of the cells were assessed. -IFN and 1 , 25 (OH)₂D₃ additively suppressed cell growth, especially the number of blast cells decreased. The expression of -naphthylbutyrate esterase (NBE) activity appeared to be promoted but that of naphthol AS-D chloroacetate esterase (NAE) activity was apparently suppressed by the addition of -IFN and/or 1 , 25 (OH)₂D₃. The percentage of NBT reduction-positive cells and latex-phagocytizing cells was only slightly increased by both agents. These results indicate that -IFN and 1 , 25 (OH)₂D₃ cooperate to induce monocytoid differentiation of the patients' blast cells. Combination therapy with both agents merits further study.     

Ultrastructural changes in A-cells exposed to diabetic hyperglycaemia. Observations made on pancreas of chinese hamsters

Summary Pancreatic A-cells of chinese hamsters with diabetes of varying severity and duration were examined by electron microscopy. Two predominant changes were observed: 1. Lysosomal digestion of secretory granules (granulolysis, crinophagy) occurred in practically all A-cells of diabetic animals but was rarely observed in those of normoglycemic controls. This is considered a response of A-cells to the cessation of glucagon release secondary to hyperglycemia. 2. In relatively degranulated A-cells of ketotic diabetic animals, dilatation of the cisternae of the RER was seen together with accumulation of pale, flocculent material, possibly reflecting persisting or enhanced glucagon synthesis. In addition, numerous maturing secretory granules were seen in the cisternae of the Golgi complex. Since these apparently contradictory phenomena may be seen in the same cell, it is suggested that granulolysis may not only result from decreased hormone release secondary to hyperglycemia but that different and independent stimulatory signals may exist for glucagon synthesis, for glucagon release, and for the initiation of granulolysis.Supported in part by the Fonds national suisse de la Recherche scientifique (Grants. No. 4848.3 and 3.154.69).     

Impairment of monocyte “lectin-like” receptor activity in Type 1 (insulin-dependent) diabetic patients

Summary In order to investigate whether the ability of peripheral blood monocytes to bind bacteria is impaired in diabetes, we studied carbohydrate-binding (lectin-like) receptors and the receptor for the Fc portion of immunoglobulin on monocytes from 25 male Type 1 (insulin-dependent) diabetic patients and 10 age-matched healthy control subjects. Peripheral blood monocytes from the diabetic patients expressed lower levels of lectin-like receptors compared to the control subjects, whereas the expression of the receptor for the Fc portion of immunoglobulin was similar in both populations. There was no correlation between the degree of lectin-like binding activity and plasma glucose concentration or glycaemic control. Recognition of unopsonized bacteria by the lectin-like receptor is impaired in Type 1 diabetes; this may affect the efficient elimination of potential pathogens.     

TCR1+ large granular lymphocyte proliferation in rheumatoid arthritis

The T-lymphoproliferative syndrome is characterized by a proliferation of large granular lymphocytes (LGL). It is often associated with neutropenia, and in 30% of cases with rheumatoid arthritis (RA). Phenotypic analysis has demonstrated that in most cases of RA with T-proliferative disease, the LGL represent T cells with a clonal rearrangement of the / T cell receptor (TCR2). Here, three patients with / TCR1⁺ LGL proliferation suffering from long-standing arthritis and neutropenia are described. The first patient with RA showed an expansion of a heterogeneous CD2⁺ CD16⁺ CD56^- LGL population, of which 30% coexpressed TCR1 with V1 rearrangement. The second patient with ankylosing spondylitis and RA was suffering from proliferation of TCR1⁺ (V9^-, V1^-), CD2⁺ CD16^- CD56^- LGL with low coexpression of CD8. The third patient with RA was suffering from a proliferation of TCR1⁺ (V1⁺, V9^-) CD4^- CE8^- CD16^- CD56^- lymphocytes. On the basis of these unusual findings, the pathogenetic role of TCR1⁺ T cells in RA is discussed.     

Tissue osmolality,metabolic response,and reperfusion in myocardial ischemia

Summary We studied the effect of tonicity of the perfusate during reperfusion after global ischemia, in both the rat and the porcine heart. After 50 min, tissue osmolality increased by about 40 mOsm/kg. Normotonic as well as hypertonic reperfusion resulted in limited areas of no-reflow. Metabolic restoration after reperfusion was not dependent on the tonicity of the perfusate, nor was recovery of contractility. Hypertonic reperfusion induced a higher coronary flow rate. In porcine hearts, scatter of metabolic data indicated inhomogencity of reperfused tissue. The results differ substantially from data obtained after reperfusion of regionally ischemic hearts. Reasons for these differences are discussed.     

Triplication (/ααα<Superscript>Anti3.7</Superscript>) or deletion (-α<Superscript>3.7</Superscript>/) association in Argentinian β-thalassemic carriers

Prevalence of alpha gene triplication or deletion in -thalassemia carriers was studied in 109 unrelated individuals in Rosario, Argentina. In different populations -^3.7 allele presents a higher prevalence than ^anti3.7; thus, -thalassemia associated with -thalassemia is more frequently observed. Nevertheless, this event was detected in only one case (0.9%), while the association with alpha triplication was present in two subjects (1.8%).     

Bone marrow and peripheral blood globin chain biosynthesis in iron deficiency

Summary Globin chain synthesis was studied in 13 iron-deficient patients. The mean whole-cell globin / ratio in the peripheral blood of 11 patients was 1.05±0.06 which is similar to the value 0.99±0.08 obtained for 10 controls. The ratios odtained for stroma-free globin were not significantly different from those of whole cell preparations. In contrast, the / ratio of bone marrow was 0.73±0.14 in 10 iron deficient patients, which is significantly lower than that of controls. Two other patients had decreased / ratios in the peripheral blood, probably because of the presence of an -thalassemia gene. These results demonstrate a reduced rate of synthesis of chains relative to that of chains in the bone marrow of iron-deficient patients that is not demonstrable in the peripheral blood.This work was partly supported by Fundação de Amparo à Pesquisa do Estado de São Paulo, Brazil     

EGF and TGF-β1 Gene Expression in Chronically Rejecting Small Bowel Transplants

Long-term survival of small bowel transplants ishampered by chronic rejection. Epidermal growth factor(EGF) and transforming growth factor (TGF-)have opposing, regulatory roles in normal intestinal physiology and may be involved in thepathogenesis of chronic intestinal rejection. Our aimwas to investigate the expression of EGF andTGF-₁ in chronically rejecting smallbowel transplants. Orthotopic small bowel transplantation was performed inthe allogeneic DA-to-AS rat combination; Cyclosporin wasadministered temporarily to prevent acute rejection.Controls were DA isografts and normal DA rats. PreproEGF and TGF-₁ geneexpression was evaluated by northern blot analysis ofthe ileum RNA and standardized againstglyceraldehyde-3-phosphate-dehydrogenase expression.Allografts demonstrated functional impairment and histological features of chronicrejection, whereas isografts appeared normal. Allograftsdemonstrated a significant reduction of EGF mRNA whencompared to DA isografts. No significant changes were detected in TGF-₁expression in either allogeneic or syngeneic grafts. Inconclusion, this study demonstrates reduced preproEGFand preserved TGF-₁ gene expression inchronically rejecting small bowel transplants.     

B cell adrenoceptors and sulphonylurea-induced insulin release in mouse islets

Summary Interactions of tolbutamide and glibenclamide with B cell adrenoceptors have been reported. This study evaluated the possible role of such interactions in the stimulation of insulin release. Mouse islets were incubated in the presence of 10 mmol/l glucose alone or with tolbutamide (10 mol/l) or glibenclamide (0.02 mol/l). At 0.01–10 mol/l, blockers of ₂-adrenoceptors (yohimbine, idazoxan) or ₁-adrenoceptors (prazosin) had practically no effect on glucose-induced insulin release and did not affect its potentiation by sulphonylureas, except for a slight increase by 10 mol/l prazosin and idazoxan. Nonspecific -blockers (phentolamine, dihydroergotamine) increased control release at 10 mol/l, but only the latter amplified the response to tolbutamide. Blockers of -adrenoceptors were tested at 0.1–100 mol/l: propranolol (₁, ₂), metoprolol (₁) and compound ICI 118-551 (₂). They increased glucose-induced insulin release at 100 mol/l but variably altered the effect of sulphonylureas. Blockers of adrenoceptors have, thus, no effect on insulin release in vitro at therapeutic concentrations. At high concentrations, they non-specifically affect the action of sulphonylureas. We conclude that an interaction with B cell adrenoceptors is not involved in the insulinotropic action of sulphonylureas.     

Presence of Two Signaling TGF-β Receptors in Human Pancreatic Cancer Correlates with Advanced Tumor Stage

Transforming growth factor- (TGF-)signal transduction is mediated via specific cellsurface signaling TGF- receptors, most notably thetype I ALK5 (TR-I_ALK5)and the type II(TR-II). We evaluated TR-I_ALK5 andTR-II expression in 41 human pancreatic cancertissue samples and correlated these findings withclinical data of the patients. Northern blot analysisindicated that, in comparison with the normal pancreas,pancreatic adenocarcinomas exhibited 8.0-fold and4.5-fold increases (P < 0.01), respectively, in mRNAlevels encoding TR-I_ALK5 andTR-II. In situ hybridization showed that both TR-I_ALK5 mRNAwere highly expressed in the majority of pancreaticcancer cells. Immunohistochemical analysis ofTR-I_ALK5 and TR-II revealedpositive immunostaining in 73% and 56% of the tumors, respectively. Both receptorswere concomitantly present in 54% of the pancreaticcancer samples. The presence ofTR-I_ALK5 or TR-II and theconcomitant presence of TR-I_ALK5 and TR-II in the cancer cells was associatedwith advanced tumor stage (P < 0.01). These findingsshow that in many human pancreatic cancers, increasedlevels of the two signaling TRs are present. The presence of the signaling TRs inadvanced tumor stages indicates a role in diseaseprogression.