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%).     

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.     

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.     

Effects of Cytokines on the Binding of Leukocytes to Cultured Rat Hepatocytes and on the Expression of ICAM-1 by Hepatocytes

Adhesions of leukocytes to hepatocytes andsinusoidal endothelial cells mediates the induction andprogression of hepatic injury. However, in contrast toendothelial cells, information regarding the regulation of interactions between leukocytes andhepatocytes is limited. In the present study, weinvestigated the effect of inflammatory mediatorsincluding lipopolysaccharide (LPS), staphylococcalenterotoxin B (SEB), interferon- (IFN-), tumornecrosis factor- (TNF-), andinterleukin-1 (IL-1) on the adhesion ofpolymorphonuclear leukocytes or lymphocytes to primarycultured rat hepatocytes, and on the expression of intercellular adhesionmolecule-1 (ICAM-1) gene in hepatocytes. Bothpolymorphonuclear leukocyte and lymphocyte adhesion tohepatocytes were enhanced after exposure of hepatocytes to IFN- and TNF-, but not afterexposure to LPS, SEB or IL-1. The adhesion inducedby either IFN- or TNF- was inhibited bymonoclonal antibodies against ICAM-1 or lymphocytefunction-associated antigen-1 (LFA-1). Nonstimulated hepatocytesexpressed faintly ICAM-1 mRNA, which increased slightlyduring the culture period. ICAM-1 mRNA expression wasup-regulated to a greater extent by incubating hepatocytes with IFN- or TNF-,and peaked after 12 hr of incubation with TNF-and after 24 hr with IFN-. These results indicatethat IFN- and TNF- induce the expressionof ICAM-1 on parenchymal hepatocytes and that theLFA-1-ICAM-1 pathway plays an important role in theinteraction between hepatocytes and neutrophils orlymphocytes.     

Heterophilic interactions between cell adhesion molecule L1 and α<Subscript>v</Subscript> β<Subscript>3</Subscript>-integrin induce HUVEC process extension <Emphasis Type="Italic">in vitro</Emphasis> and angiogenesis <Emphasis Type="Italic">in vivo</Emphasis>

Cell adhesion molecule L1 was implicated in angiogenic processes, tumor formation and metastasis. Here, we provide evidence that the sixth Ig-like domain of L1 (L1Ig6) interacts with _{v 3} to induce process extension of human umbilical vein endothelial cells (HUVECs) in vitro and angiogenesis in vivo. HUVECs formed network-like structures on full-length L1 or L1Ig6 substrates comparable to structures found on matrigel. In the presence of mab _{v 3} or cyclic RGD, apoptosis was induced. In fibrin matrices where L1Ig6 was covalently incorporated, HUVECs formed multicellular and hollow processes through interactions between cell-surface _{v 3} and RGD-sites of matrix-immobilized L1Ig6. No such processes were induced by L1Ig6 having non-functional RDG-sites, or in the presence of mab _{v 3} or cyclic RGD. In those matrices, increased apoptosis was found. Co-immunoprecipitation of L1 or L1Ig6 with _{v 3} suggests close interactions. Furthermore, L1Ig6 stimulated HUVECs showed increased tyrosine phosphorylation of _{v 3} and phosphorylation of MAP kinases (ERK1 and ERK2) but not AKT indicating specific activation of _v and _{v 3} followed by activation of downstream kinases. Application of L1Ig6-modified fibrin matrices on CAMs induced 50–60% increased _v and _v3 protein expression and in vivo angiogenesis indicated by ~50% increased mean vascular length density. The results demonstrate angiogenic potential of L1Ig6 involving ligation and activation of _v3     

Enhanced Expression of Transforming Growth Factor (TGF) -α Precursor and TGF-β1 During Paneth Cell Regeneration

An intravenous injection of diphenylthiocarbazone (dithizone), a zinc chelator, induces selective killing and rapid regeneration of Paneth cells, which have a large amount of zinc in their cytoplasmic granules. We examined the expression pattern of transforming growth factor (TGF) - and TGF-₁ in this regenerative process. Messenger RNA expression of TGF- and TGF-₁ reached their peaks at 12 and 24 hr after dithizone injection, respectively. Protein expression of TGF- precursor and TGF-₁ increased to a maximum at 24 and 72 hr, respectively. Their immunoreactivities were localized in the epithelial cells in the vicinity of Paneth cells, whereas they were prominent in the upper half of the crypts in control rats. In conclusion, destruction of Paneth cells induced TGF- precursor expression, followed by an increase of TGF-₁ especially in the crypt bases. This unique expression pattern of two growth factors may be involved in rapid regeneration of Paneth cells.     

Thalassemia intermedia: compound heterozygous β∘/β+-thalassemia and co-inherited heterozygous α+-thalassemia

Summary The relative excess of - over -globin chains in the erythroid precursors is the chief pathophysiological factor of homozygous -thalassemia. The clinical picture is usually characterized by a transfusion-dependent dyserythropoietic anemia (thalassemia major). However, some patients present with moderate anemia that does not require regular blood transfusions (thalassemia intermedia). The molecular heterogeneity of -thalassemia mutations and changes of - and -globin gene expression play an important role in modifying the clinical phenotype. We report here on a female Greek patient with homozygous -thalassemia but normal growth and development, excellent exercise tolerance, and no need of blood transfusions. She is thus mildly affected clinically, although there is marked pallor, jaundice, and hepatosplenomegaly. These signs correspond to her marked hypochromic, microcytic anemia with erythroid hyperplasia of the bone marrow. -Globin genotyping shows her to be compound heterozygous for the codon 39 C T -nonsense mutation and for the T C ⁺-mutation at position 6 of the splice consensus at the exon 1/intron 1 junction (CD39 C T/IVS 1–6 T C). -Globin gene mapping demonstrates the presence of a 3.7-kb ⁺-thalassemia deletion on one allele (–^3.7/). Taken together, this study identifies a complex interaction of genetic factors that do not significantly alter the clinical phenotype when present alone but ameliorate the course of homozygous -thalassemia when inherited in combination.Abbreviations Hb hemoglobin - Hct hematocrit - HPFH hereditary persistence of fetal hemoglobin - IVS intervening sequence - MCH mean corpuscular hemoglobin - MCV mean corpuscular volume - PCR polymerase chain reaction     

The antigenicity of human hemoglobins

Summary The correlation of the antigenicities among native hemoglobins and their subunit chains were investigated by the absorption of antisera and the combination of urea added immunoelectrophoresis with double diffusion. Alphachain showed identity with Hb-F but partial identity with -chain and Hb-A. Beta-chain showed identity with Hb-A but -chain and Hb-F showed partial identity with this chain. Gamma-chain showed identity only with Hb-F and its antigenicity was considered as being different from those of - or -chains.The lines of -, -and -chains were reconfirmed from the facts that the appearance of them depended always on the existence of anti-Hb-A or anti-Hb-F antibodies in the absorbed antisera and the minor component lines of

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Zusammenfassung Die Zusammenhänge der Antigenität zwischen nativen Hämoglobinen und deren Unterketten wurden mit der Absorption der Antiseren und der Kombination der Harnstoff-Immunelektrophorese und Doppeldiffusion untersucht. Die -Kette zeigte Identität mit Hb-F, aber nur partielle Identität mit der -Kette und Hb-A. Die -Kette war in ihrer Antigenität mit Hb-A identisch, die -Kette und Hb-F waren teilweise identisch mit der -Kette. Die -Kette zeigte die Identität mit Hb-F; es wird angenommen, daß ihre Antigenität verschieden von der -oder -Ketten ist.Für das Auftreten der Linien der -, - und -Ketten müssen Anti-Hb-A-oder Anti-Hb-F-Antikörper in den absorbierten Antiseren vorhanden sein, außerdem fusionieren die schwächeren Linien der Doppeldiffusion nicht mit irgendwelchen Linien der Unterketten. Auch gereinigte - oder -Ketten wurden zur Feststellung ihrer Linien benutzt.

     

The effects of parabiosis on serum and kidney glycosidase activities in spontaneously diabetic mice

Summary Spontaneously diabetic non-obese mice of the ICR strain were newly inbred in Shionogi laboratory, Japan. Animals became diabetic suddenly, more frequently and severely in females. Blood glucose levels were 452±73 mg/100 ml with serum insulin levels of < 1.0 U/ml in the fed state. Parabiosis with normal control ICR mice for 2 weeks decreased the blood glucose level to 260±51 mg/ 100ml (P<0.01) and resulted in serum insulin levels of 46.0±18.0 U/ml (P<0.01). Kidney homogenate -N-acetylglucosaminidase and -galactosidase activities were reduced in diabetic mice (42% and 44% decrease respectively) (P<0.025 and P<0.001), and restored almost to normal after 2 weeks of parabiosis. Renal -mannosidase activity was decreased 43% (P<0.001) in the diabetic mice but unaffected by parabiosis. Serum -N-acetylglucosaminidase, -galactosidase and -glucosidase activities were significantly increased in diabetic mice (179%; 233% and 58% increase respectively) (P<0.005, P<0.001 and P<0.001), and returned to normal with parabiosis.     

Gabexate mesilate, a synthetic protease inhibitor, attenuates carbon tetrachloride-induced liver injury in rats

Background Gabexate mesilate, a synthetic protease inhibitor, is used to treat acute pancreatitis and disseminated intravascular coagulation because it inhibits various serine proteases; however, whether gabexate mesilate prevents acute liver failure has not yet been studied. The aim of the present study was to investigate the effect of gabexate mesilate in carbon tetrachloride (CCl₄)-induced liver injury in rats.Methods Acute hepatic failure was induced by administration of CCl₄ intragastrically to male Sprague–Dawley rats. The effects of gabexate mesilate were examined in terms of serum transaminase levels, liver histology, and the prognosis of rats.Results Gabexate mesilate treatment significantly decreased the elevation of serum transaminase levels and improved liver histology 24h after the administration of CCl₄ (0.2ml/100g rat weight). Plasma tumor necrosis factor- (TNF-) and interleukin-1 (IL-1) decreased significantly in the gabexate mesilate-treated rats compared with saline-treated rats. Gabexate mesilate treatment also significantly improved survival rate after a lethal dose of CCl₄ (0.5ml/100g rat weight) from 0% to 20%.Conclusions Gabexate mesilate treatment attenuated CCl₄-induced liver injury via a suppression of proinflammatory cytokine production. In addition, these investigations suggest that gabexate mesilate treatment may provide therapeutic strategies for human acute liver failure.     

Interleukin-1β Inhibits Growth Factor-Stimulated Restoration of Wounded Rat Gastric Epithelial Cell Monolayers

We examined the effect of interleukin-1(IL-1) on spontaneous and enhanced restoration(cell migration and proliferation) using an in vitrowound model comprising a confluent monolayer of ratgastric epithelial RGM1 cells. Repair of an artificialwound in a cell monolayer was found to be time- andconcentration-dependent when the cells were incubatedwith epidermal growth factor (EGF) or transforming growth factor (TGF)- alone for up to 24hr. The growth factors also stimulated DNA synthesissignificantly for 24 hr in a concentration-relatedmanner. IL-1 had no effect on wound restoration in the absence of the growth factors. However, itmarkedly inhibited the restoration enhanced by EGF andTGF-, the inhibition being about 60% and 70%,respectively. In addition, IL-1 significantly reduced the DNA synthesis stimulated by thegrowth factors. The EGF- and TGF--enhancedrestoration was reduced by about 30% by mitomycin C,which potently inhibited the stimulated DNA synthesis.Mitomycin C had no effect on the spontaneous restoration.Even when treated with mitomycin C, the inhibitoryeffect of IL-1 on the enhanced wound repair wasstill observed; however, the extent of the inhibition was decreased. These results indicate thatIL-1 inhibits the migration as well as theproliferation of gastric epithelial cells enhanced byEGF and TGF-, resulting in a failure of woundhealing.     

Expression and secretion of alpha1-proteinase inhibitor are regulated by proinflammatory cytokines in human pancreatic islet cells

Aims/hypothesis Alpha1-proteinase inhibitor (1-PI) has been considered a key player in inflammatory processes. In humans, the main production site of 1-PI is the liver, but other tissues, including pancreatic islets, also synthesise this molecule. The aims of this study were to assess the islet cell types that produce 1-PI, to determine whether 1-PI is actually secreted by islet cells, and to assess how its production and/or secretion are regulated.Methods Expression of 1-PI in human islet cells was assessed by immunofluorescence, electron microscopy and western blotting. Release of 1-PI was analysed by reverse haemolytic plaque assay and ELISA. The effects of cytokines on 1-PI synthesis and secretion were tested.Results Immunofluorescence showed that alpha and delta cells do express 1-PI, whereas beta cells do not. By electron microscopy, we demonstrated a colocalisation of 1-PI with glucagon and somatostatin within secretory granules. Immunolabelling also revealed localisation of 1-PI within the Golgi apparatus, related vesicles and lysosomal structures. The expression of 1-PI in islet cells was also demonstrated by western blotting and ELISA of protein extracts. ELISA and reverse haemolytic plaque assay showed that 1-PI is secreted into the culture medium. Treatment of islet cells with IL-1 and oncostatin M for 4 days increased the production and release of 1-PI.Conclusions/interpretation Our results demonstrate that 1-PI is expressed by the alpha and delta cells of human islets, and that proinflammatory cytokines enhance the production and release of this inhibitor.     

Microheterogeneity of acute phase proteins in patients with clinically active and clinically nonactive osteoarthritis

Summary Microheterogeneity of two acute phase glycoproteins, -1-acid glycoprotein (AGP) and -1-antichymotryspin (ACT), concentrations of AGP, ACT, and C-reactive protein (CRP), and levels of three cytokines: interleukin 1 (IL-1-), interleukin 6 (IL-6), and tumor necrosis factor (TNF-) were determined in 61 serum samples and 7 synovial fluids (SFs) obtained from patients (n=61) with osteoarthritis. Using affinity immunoelectrophoresis with concanavalin A (conA), a significant decrease in the reactivity of AGP and ACT with this lectin was found in patients with clinically active osteoarthritis when compared to those with clinically nonactive disease (p<0.001 and p<0.05, respectively). There was no increase in the concentration of AGP, ACT, and C-reactive protein (CRP) in the sera examined. In particular, no increase in the serum level of these proteins was found in the patients with clinically active disease. Low concentrations of IL-6 and TNF- were found in most sera and SFs examined. In 6 out of 7 SFs available, IL-6 concentrations were higher than in the respective serum samples but for TNF- the same could be shown in one case only. Low concentrations of IL-1- were found in 4 serum samples obtained from patients with clinically active osteoarthritis and in no SF specimen studied. In the entire group, serum level of TNF- correlated weakly with the AGP and ACT reactivity coefficients with conA (r=0.3634, p<0.005 and r=0.3324, p<0.02, respectively).Our findings suggest that there are changes in the microheterogeneity of acute phase glycoproteins in some patients with osteoarthritis similar to those observed in rheumatoid arthritis and other chronic inflammations. Possible mechanisms of the involvement of cytokines in the regulation of glycosylation of acute phase glycoproteins in osteoarthritis are discussed.     

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     

Expression and prognostic roles of integrins and interleukin-1 receptor type I in patients with ductal adenocarcinoma of the pancreas

To Investigate the prognostic indicator, we examined the expression of ₆- and ₅- integrin and interleukin-1 receptor type I (IL-1RI) immunohistochemically, and analyzed the correlation between immunohistochemical findings and clinicopathological factors in pancreatic cancer. In patients with a strongly expressing ₆- integrin subunit or weakly expressing ₅₁-integrin in pancreatic cancer tissues there was a significant association with advanced TNM stage (P = 0.027 and 0.014, respectively), presence of liver metastases (P = 0.032 and 0.002, respectively), and poor prognosis (P = 0.0155 and 0.0056, respectively). In patients with a weakly expressing ₆ integrin subunit or weakly expressing ₅₁-integrin in noncancerous pancreatic tissues there was a significant association with poor prognosis (P = 0.0324 and 0.0396, respectively). Multivariate analysis demonstrated that strong expression of ₆- and weak expression of ₅₁-integrin were found to be independent prognosticators in pancreatic cancer patients. Our present results indicate that ₆₁- and ₅₁-integrin expression can be a significant prognostic indicator in pancreatic cancer.     

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.     

Interleukin-2-activated killer cell activity in colorectal tumor patients: evaluation of in vitro effects by prothymosinα1

The effects of prothymosin 1 (Pro 1) in combination with interleukin-2 (IL-2) on peripheral blood lymphocytes from 50 colorectal tumor patients at different stages were studied with respect to immunocytotoxicity, adhesion to cultured SW620 colon carcinoma cells, secretion of cytokines and expression of adhesion and surface marker molecules. On average, the patients showed lower natural killer (NK) cell activity than healthy donors, which was associated with a lower adhesion capacity to the tumor target cells. The NK cell activity of the patients was inversely related to the tumor stage. The generation of lymphokine(IL-2)-activated killer (LAK) cell activity was found to be comparable on lymphocytes from healthy individuals and patients and was not correlated to tumor stage. Pro 1 stimulated patients' LAK cell activity only, primarily at the early stage (Dukes A/B). The Pro 1 effect was associated with an increased adhesion of lymphocytes to tumor target cells and an increased secretion of the deficient IL-2-induced IFN secretion. No significant effects on the low level of TNF secretion was noted. By flow cytometry, Pro 1 in combination with IL-2 augmented the expression of the NK cell markers CD56, CD16/56, the subset CD3/16/56 and CD25 on lymphocytes of the patients. In contrast, Pro 1 was equally effective by increasing the expression of CD18 and CD11a, on lymphocytes from the patients and from normal controls. In conclusion, Pro 1, in combination with IL-2, can partially normalize lymphocyte deficiencies of colon cancer patients in vitro. This potential might provide an experimental basis for applying Pro 1 or related thymic peptides in selected immunotherapies against colorectal tumors.Abbreviations Pro 1 prothymosin 1 - NK natural killer - LAK lymphokine-activated killer - IL-2 interleukin-2 - TNF tumor necrosis factor - IFN interferon - PBL peripheral blood lymphocytes - ELISA enzyme-linked immunosorbent assay     

Structural lability of zinc-containing secretion granules of pancreatic β-cells after exposure to hydrogen sulphide

Summary Treatment of vertebrate pancreatic islet tissue with hydrogen sulphide, thus initiating the sulphide-silver procedure for ultrastructural visualization of heavy metals in tissues, evoked marked swelling in zinc-containing secretion granules of -cells in several species rapidly leading to disruption of many granules. Other organelles of the -cells were unaffected, as also were the secretion granules of adjacent zinc-containing ₂-cells. Likewise, -and ₂-granules with no heavy metals or only traces of them, like those of the guinea pig and the coypu, were all well preserved after gassing with hydrogen sulphide. It is suggested that this observation may give some information on insulin-zinc-sulphydryl relationships in vivo.This work was supported by grants from the Swedish Medical Research Council (Project Nr. K68-12X-718-03), the Nordic Insulin Fund, and the Medical Faculty, University of Umeå.     

Gene expression of cytokines suppressing hematopoietic progenitor cells in lymphoid malignancies

Summary The expression of cytokine genes for tumor necrosis factor (TNF), lymphotoxin and transforming growth factor (TGF), all of which are known to suppress normal hematopoiesis, was investigated in 32 patients with lymphoid malignancies using Northern blot analysis. Messenger RNA (mRNA) for TNF, lymphotoxin and TGF was detected in 9 cases, 2 cases and 7 cases, respectively. When the relationship between cytokine gene expression and surface phenotype was analyzed, the expression of CD19 correlated significantly with expression of the TNF gene (P<0.05). This suggests that B cell malignancies are likely to produce TNF. When the hematological parameters of patients expressing and not expressing the gene were compared, the expression of TNF mRNA was found to correlate with more profound anemia in acute lymphoblastic leukemia (P<0.05). Both granulocyte and platelet counts were lower in patients expressing TNF mRNA; however, the decreases were not significant. Neither lymphotoxin nor TGF gene expression correlated significantly with any hematological parameter.Abbreviations TNF tumor necrosis factor - TGF transforming growth factor - IL interleukin - ALL acute lymphoblastic leukemia - CLL chronic lymphocytic leukemia - ATLL adult T-cell leukemia/lymphoma - NHL non-Hodgkin's lymphoma - MM multiple myeloma Partly supported by grants-in-aid from the Ministry of Education, Science and Culture of Japan (60770949, 63015063, 02256102, 03670325) and from the Fukuoka Anti-Cancer-Society.