Suppression of T-lymphoma cell apoptosis by monoclonal antibodies raised against cell surface adhesion molecules

We have previously established a mouse malignant T-lymphoma CS-21 cell line that preferentially metastasizes to lymph nodes after s.c. inoculation into BALB/c mice. The CS-21 lymphoma cells were grown in vitro in the presence of CA-12 stromal cells isolated from lymph nodes. When CS-21 cells were cultured alone, they underwent apoptotic cell death with DNA fragmentation. In contrast, the culture of CS-21 cells attached to a monolayer of CA-12 stromal cells prevented CS-21 cell apoptosis and enhanced cell proliferation. To identify the cell adhesion molecules, we developed monoclonal antibodies (mAbs) directed against CS-21 cell surface proteins. Fourteen mAbs partially inhibited the binding of CS-21 cells to a CA-12 stromal cell monolayer. MCS-5 (mAb against CS-21 No. 5) directed against a M(r) 168,000 cell membrane protein and MCS-19 against a M(r) 23,000 protein were found to suppress apoptosis and to stimulate CS-21 cell growth. Soluble factors secreted from CA-12 stromal cells enhanced CS-21 cell growth but were not sufficient to prevent apoptosis. In the presence of both stromal cell-secreted factors and mAbs MCS-5 or MCS-19, CS-21 lymphoma cells evaded apoptosis and grew as fast as in the coculture with CA-12 stromal cells. Because of these results, we conclude that CA-12 lymph node stromal cells support CS-21 lymphoma cell growth by secreting paracrine growth factors and by presenting receptors for the M(r) 168,000 and M(r) 23,000 cell surface adhesion molecules of CS-21 cells that transmit signals to prevent CS-21 cell apoptosis.

Control of apoptosis and growth of malignant T lymphoma cells by lymph node stromal cells

We have previously established the malignant T lymphoma CS-21 cell line from a spontaneous lymphoma in a BALB/c mouse. CS-21 lymphoma cells grew continuously when they were cocultured with stromal CA-12 cells prepared from lymph nodes. CS-21 lymphoma cells, however, could not proliferate by themselves, and they underwent apoptosis when separated from the stromal CA-12 cells. Apoptosis of CS-21 lymphoma cells was determined by observation of morphological changes using a transmission electron microscope and also by detection of nuclear DNA degradative fragments of oligonucleosomal size. Stromal CA-12 cells secreted soluble factors that enhanced DNA synthesis in CS-21 lymphoma cells. The soluble factors, however, were not sufficient to prevent apoptosis of CS-21 cells. Apoptosis of CS-21 lymphoma cells was suppressed only when the CS-21 lymphoma cells were cocultured with substantial numbers of CA-12 cells. The results suggest that the lymph node stromal CA-12 cells played an important role in the growth of CS-21 lymphoma cells by providing at least two different signals. One signal prevented CS-21 cells from apoptotic cell death by direct cell-to-cell contact, and the other signal enhanced the CS-21 cell proliferation by secreted soluble factors.

[Lymphatic metastasis and cell adhesion, growth and growth inhibition]

Malignant tumor cells often metastasize to regional and distant lymph nodes. The mechanisms of lymphatic metastasis, however, have not been well understood. To investigate these mechanisms, we used mouse CS-21 malignant T lymphoma cells which form tumors at subcutaneous sites and metastasize to lymph nodes with a high incidence. In contrast, CS-21 cells do not metastasize to other organs following intravenous injection. CS-21 lymphoma cells continuously grew in vitro when the cells were cocultured with CA-12 stromal cells isolated from lymph nodes. However, when CS-21 cells were separated from the stromal cells, they underwent apoptosis which was characterized by nucleus condensation and DNA fragmentation. We have developed monoclonal antibodies against CS-21 cell surface molecules by intrasplenic injection of the cell membranes. Several clones of monoclonal antibodies were able to partially inhibit adhesion of CS-21 cells to a monolayer of CA-12 stromal cells. Treatment of CS-21 cells with the monoclonal antibodies which specifically bind to the cell surface components of M(r) -168K and -23K prevented the apoptosis of CS-21 cells after separation from the stromal cells. In the experiments using Transwell chambers we found that the growth of CS-21 cells was also supported by soluble factors secreted from CA-12 stromal cells. The secreted factors were, however, not sufficient to prevent CS-21 cell apoptosis. The result suggested that the stromal cells of lymph nodes play an important role in lymphatic metastasis of CS-21 lymphoma cells by cell-cell adhesion and secretion of soluble factors that prevent apoptosis of lymphoma cells and enhance their growth in concert.

The chemoluminescence response of human polymorphonuclear leukocytes to Escherichia coli O and K antigens

The interactions between Escherichia coli O or K antigens and polymorphonuclear leukocyte function were studied. Five types of O antigen and three types of K antigen were extracted from E. coli. These included O1, O6, O75 and K1 antigens from pyelonephritopathogenic strains, O44 and K74 antigens from an enteropathogenic strain and O14 and K7 antigen from a standard strain. The antigens all reacted specifically to their specific antisera and no cross-reactions were observed. The O1 or O44 antigen stimulated a significantly greater chemoluminescence response in polymorphonuclear leukocytes obtained from normal volunteers than O75, O6 or O14 antigen. In addition, the K1 or K74 antigen stimulated polymorphonuclear leukocytes significantly more than K7 antigen. These results suggest that pyelonephritopathogenic or enteropathogenic E. coli may produce severe tissue damage as a result of the response to their O or K antigens, as well as via adhesive agents such as pyelonephritopathogenic P-pili or the enteroadhesive factor, and exotoxins such as hemolysin or verotoxin.

Increased receptor binding of low-density lipoprotein from individuals consuming a high-carbohydrate, low-saturated-fat diet

The substitution of saturated fat by complex carbohydrate, according to current dietary recommendations, results in a decrease of plasma and low-density lipoprotein (LDL) cholesterol levels. To determine whether this decrease might result from structural and thus functional changes in LDL particles, the binding internalization and degradation of 125I-LDL were measured using TR715-19 cells, a mutant CHO line into which has been transfected the human LDL receptor, and in which measurements of binding are highly reproducible. Eleven nondiabetic subjects (35 +/- 4 years, 27% +/- 3% body fat) were studied after they had 15% protein, and 560 mg cholesterol/d and the other containing 21% fat (6% saturated), 65% carbohydrate, 14% protein, and 524 mg cholesterol/d.LDL cholesterol levels decreased form 125 +/- 6 to 108 +/- 5 mg/dl (P < .01) on the high-carbohydrate diet. There was an increase in the binding affinity of LDL (Kd 6.6 +/- 2.6 v 7.3 +/- 2.7 micrograms/mL +/- SD; P < .02), and internalization (P < .10), and degradation (P < .05) were also higher. The data suggest that decreasing dietary saturated fat may cause alterations in LDL composition that result in increased receptor clearance; this may partially explain the LDL-decreasing effect of this dietary change.

Inhibition of salvage synthesis of nucleic acid by adenosine 3',5'-cyclic decylphosphoramidate in mastocytoma P-815 cells

Constant exposure of mastocytoma P-815 cells to adenosine 3',5'-cyclic decylphosphoramidate (1), which is permeable to the cell membrane and resistant to the action of phosphodiesterase, caused a dose-dependent (1 to 50 microM) inhibition in the synthesis of DNA and cell proliferation. Pretreating the cells with compound 1 (20 microM, 4 h) caused considerable inhibition of the incorporation of [3H]thymidine ([3H]TdR) into [3H]deoxythymidine 5'-triphosphate ([3H]dTTP) and that of [14C]hypoxanthine into nucleic acid, but not the synthesis of [14C]dTTP from [U-14C]aspartate. These results indicate that compound 1 preferentially inhibits the salvage synthesis of intracellular nucleotides and nucleic acids. Thymidine kinase, a key enzyme in salvage synthesis of nucleotides, was almost undetectable in cells pretreated with compound 1 at 20 microM for 4 h or at 5 microM for 15 h. On the other hand, compound 1 activated partially purified cAMP-dependent protein kinase A from bovine heart. Judging from these observations, it is likely that compound 1 readily permeates the cell membrane, activates cAMP-dependent protein kinase, then inhibits the salvage synthesis of nucleotides and nucleic acids by inhibiting thymidine kinase, which results in the inhibition of cell growth.

Neutrophil priming by granulocyte colony stimulating factor and its modulation by protein kinase inhibitors

Upon stimulation by various ligands, freshly isolated human peripheral neutrophils (PMN) respond in a variety of ways, such as superoxide (O2-.) generation, phagocytosis enzyme release, migration etc. Chemotactic peptide formylmethionyl-leucyl-phenylalanine (FMLP) and opsonized zymosan activate neutrophils by a receptor-mediated mechanism, while phorbol myristate acetate and dioctanoylglycerol activate the cells by a mechanism involving Ca(2+)-and phospholipid-dependent protein kinase (PKC). Receptor-mediated but not PKC-mediated O2-. generation in PMN was enhanced by the priming of recombinant human granulocyte colony stimulating factor (G-CSF). FMLP-dependent luminol chemiluminescence was also enhanced by G-CSF. However, no appreciable enhancement was observed in FMLP-induced intracellular calcium ion concentration ([Ca2+]i). Enhancement of FMLP-induced generation of O2-. by G-CSF was inhibited by genistein or alpha-cyano-3-ethoxy-4-hydroxy-5-phenylthiomethylcinnamamide (ST 638), inhibitors of tyrosine kinase (TK), and was stimulated by staurosporine and 1-(5-isoquinolinesulfonyl)-3-methyl-piperazine (H-7), inhibitors of PKC. The ED50 values of genistein and ST 638 for the inhibition of the FMLP-induced O2-. generation from G-CSF were 0.5 and 5 microM, respectively. In contrast, O2-. generation by PKC activation without G-CSF priming was inhibited by stauroporine and H-7, but was stimulated by genistein and ST 638. These results suggested that the enhancing effect of G-CSF on receptor-mediated generation of the O2-. might be regulated by protein kinases, such as TK and PKC, and that the TK inhibitor selectively inhibited the G-CSF-primed receptor-mediated O2-. generation of neutrophils.

Effect of adenosine 3',5'-cyclic monophosphate derivatives on acute liver injury induced by carbon tetrachloride

The inhibitory effects of 12 synthetic N6-alkyl cAMPs, 8-substituted cAMPs and cAMP alkylphosphoramidate derivatives (50 or 100 mg/kg, bolus, i.p.) on serum GOT and GPT activities and hepatocyte cytoplasmic vacuolation were examined in male Fischer 344 rats, which were exposed to CCl4 (0.5 mg/kg, p.o.) 30 min prior to the administration of cAMP derivatives. In CCl4-treated rats 6 h later, serum GOT and GPT levels were elevated 10- and 12-fold higher than those of vehicle rats, respectively. Treating CCl4-exposed rats with all cAMP derivatives, except those of alkylphosphoramidate, significantly decreased the levels of serum enzymes. Based on the effects of both serum GOT and GPT elevation, N6-butyl- and N6-heptyl-cAMP were the most potent. It was also observed histopathologically, that both compounds inhibited the occurrence of cytoplasmic vacuolation in CCl4-treated liver cells. This is the first report that cAMP derivatives possess a protective effect in the liver injury model induced by CCl4.

[A case of endometrioid carcinoma arising from endometriosis of the rectum]

A very rare case with rectal endometriosis heterotopic transformed into carcinoma is reported. A 44-year-old female patient underwent colostomy due to ileus. Postoperative examinations revealed submucosal tumors all around the rectum. Low anterior resection and the closure of the colostomy were performed. Thickening in the muscular layer and serosa were observed in the resected specimen, but the mucosal surface was maintained. Histopathological observation revealed glands of the endometrium and connective fibers with glandular adenocarcinoma in the periphery. Transformation of the benign endometrial tissues into carcinoma and squamous metaplasia were observed. A diagnosis of endometrial carcinoma in the rectum was made.

Studies on the synthesis of compounds related to adenosine 3',5'-cyclic phosphate. IX. Synthesis and cytotoxic effect of adenosine 3',5'-cyclic alkylphosphoramidates

A series of adenosine 3',5'-cyclic monophosphoramidates (3, cAMP amidates), including long-chain alkyl amidates, were synthesized from adenosine 3',5'-cyclic monophosphate (1, cAMP) by means of a one-pot reaction. This reaction proceeded by the treatment of cAMP tributylammonium salt (2) with phosphorus pentachloride (PCl5) and alkylamine in N,N-dimethylformamide (DMF). Compounds 3 synthesized were investigated to determine their cytotoxic activities on the growth of mouse mastocytoma P-815 cells, mouse mammary tumor FM3A cells, and human mammary tumor ZR-75 cells in culture. It was found that compounds 3h-m showed significant cytotoxic activities against these cell lines, and that cAMP decylamidate (3j) was the most cytotoxic compound (the concentration required for 50% inhibition of cell growth, ID50 = 6.0, 15.0, 2.2 microM, respectively); the antitumor effect on P-815 cells by a total packed cell volume method showed 81.8% inhibition. The cytotoxic activity of 3 increased with the increase in alkyl chain length up to 10 carbon atoms and decreased in compounds having longer alkyl chain.

Delayed postanoxic encephalopathy after strangulation. Serial neuroradiological and neurochemical studies

A 13-year-old boy was the victim of attempted strangulation. His condition had returned to normal by the sixth day after the assault; however, from the seventh day, choreoathetosis, dystonia, and marked pseudobulbar paralysis developed in the boy. The computed tomographic scans and T2-weighted magnetic resonance images that were obtained at this time revealed low-density and high-signal intensities in the region of the bilateral putamen and caudate nucleus. These symptoms and the changes in his computed tomographic scans and magnetic resonance images subsided gradually during a 2-month period. Sequential analysis of the cerebrospinal fluid for gamma-aminobutyric acid and dopamine concentrations during his illness revealed reciprocal changes with normal recovery. Because of the delayed onset of neurological changes and the cerebrospinal fluid showing reversible symptoms, the delayed encephalopathy after strangulation had been related to the biochemical alterations that followed anoxia in the vulnerable basal ganglia.

[Basal experiments of active oxygen generation in urinary polymorphonuclear leukocytes]

Polymorphonuclear leukocytes (PMNs) play an important role in host defense system. Upon interaction with soluble or particulate matter, PMNs generate active oxygen species (AO), which act on killing of bacteria. In urinary tract infection, urinary PMNs are assumed to have bactericidal activity in urine. Basal experiments were studied on the AO generation of urinary PMNs, monitored by mainly the luminol-dependent chemiluminescence. It was indicated that urinary PMNs, isolated from patients with urinary tract infection, generated AO in physiological medium. This activity of urinary PMNs was found to be significantly inhibited rather than that of PMNs in blood, and this suppression was suggested to be time-dependent. PMNs were affected significantly by osmolarity of reaction medium. These changes were associated with intracellular free calcium. PMNs exposed in hyposmotic medium generated AO, just as they were stimulated. However PMNs exposed in hyperosmotic medium did not generate AO. The stimulation-dependent AO generation of PMNs was increased in hyposmotic solution, while in PMNs incubated at 37 degrees C for 60 min in hyposmotic solution, this generation was decreased than controls. On the other hand, the stimulation-dependent generation was decreased in hyperosmotic solution, while incubated in hyperosmotic solution, this generation was increased. These results suggest that ability of urinary PMNs is regulated by urine osmolarity and retaining time or many other factors, however urinary PMNs are primed and maintain bactericidal activity.

Turnover of asymmetric unit membranes in the transitional epithelial superficial cells of the rat urinary bladder

Asymmetric thick unit membranes were observed on the luminal surface, fusiform vesicles, and multivesicular bodies of superficial cells of rat transitional epithelium. When HRP-labeled Ricinus communis lectin (RCA-I) was injected into the rat urinary bladder, RCA-I was deposited along the luminal cell membrane and in some multivesicular bodies, but not in the fusiform vesicles either before or after contraction. When the bladder was sliced by Vibratome and stained with HRP-labeled RCA-I after fixation, RCA-I was observed in many cell organelles, including fusiform vesicles and multivesicular bodies as well as the luminal surface. When small pieces of tissue were stained en-bloc with HRP-labeled RCA-I, RCA-I was found along the luminal cell surface but not in the fusiform vesicles nor the multivesicular bodies. When HRP alone was injected into the bladder, HRP was observed in some multivesicular bodies after contraction but not in the fusiform vesicles. Various lysosomes were observed by electron microscopy. Some were wrapping multivesicular bodies in ringlike fashion, and some contained asymmetric unit membranes. These findings suggest that the asymmetric unit membranes are carried to the luminal cell membrane via the fusiform vesicles and that old luminal cell membranes are removed via the multivesicular bodies to be degraded by lysosomes.

Studies on the synthesis of compounds related to adenosine 3',5'-cyclic phosphate. VII. Synthesis and cardiac effects of N6,N6-dialkyl adenosine 3',5'-cyclic phosphates

A series of novel N6,N6-dialkyl adenosine 3',5'-cyclic phosphates N6,N6-dialkyl cAMPs) was synthesized from 2'-O-p-toluenesulfonyl cAMP (2'-O-tosyl cAMP, 2) and tested for inotropic and chronotropic activities in vitro. Treatment of 2 with excess alkyl halides and sodium hydride followed by detosylation with aqueous NaOH readily gave N6,N6-dialkyl cAMPs (3) in good yields. Various N6,N6-dialkyl cAMPs having different alkyl groups at the N6-position (9-12) were prepared by alkylation followed by detosylation of N6-alkyl-2'-O-tosyl cAMPs (4) which were obtained by the reductive alkylation of 2 with aldehydes in the presence of sodium cyanoborohydride in acetic acid or tosylation of N6-methyl cAMP. The mechanism of the detosylation is briefly discussed. Among the N6,N6-dialkylated derivatives, N6,N6-dipentyl (3f) and N6-ethyl-N6-heptyl (10e) derivatives were found to exhibit a potent positive inotropic effect and a weak positive chronotropic effect. The structure-activity relationships for the position and the length of alkyl residue are discussed.

[Delayed postanoxic encephalopathy after strangulation--the serial neuroradiological and neurochemical studies]

A 13-year-old boy was the victim of a strangulation attempt. His behavior was normal by the 6th day after the assault. However, from the 7th day, he developed choreoathetosis, dystonia and marked pseudobulbar palsy. CT and T2-weighted MRI at this time revealed a low density and high signal intensity in the region of the bilateral putamen and caudate respectively for the first time. Thereafter, these symptoms and changes in CTs and MRIs subsided gradually over two months. Sequential analysis of CSF for GABA and dopamine during illness revealed reciprocal changes each other with normal recovery. Because of delayed onset of neurological changes, and findings of CSF with reversible symptoms the delayed encephalopathy after strangulation is probably related to biochemical alteration secondary to anoxia in vulnerable basal ganglia.

Studies on the synthesis of compounds related to adenosine-3',5'-cyclic phosphate. VI. Synthesis and cardiac effects of N6,N6,2'-O-trialkyl-, N6,2'-O-dialkyl-, and 2'-O-alkyladenosine-3',5'-cyclic phosphates

The alkylation of adenosine-3',5'-cyclic phosphate (cAMP, 1) with alkyl bromides was investigated and various new alkylated cAMP derivatives, N6,N6,2'-O-trialkyl cAMPs (2), N6,2'-O-dialkyl cAMPs (3) and 2'-O-alkyl cAMPs (4), were prepared by a one step reaction without the introduction of a protecting group into 1. Compounds (2) were synthesized from 1 by treatment with alkyl bromides in the presence of NaH or potassium tert-butoxide in dimethyl sulfoxide. Compounds (3) were also synthesized from 1 under conditions similar to those of the synthesis of 2 except for the use of MeONa as a base. Compounds (4) were prepared from 1 by treatment with alkyl bromides in the presence of 18-crown-6 in dioxane-aqueous KOH solution. N6,2'-O-Dibenzyl cAMP (3e) was obtained from 1 by the same method as the preparation of 4. These new alkylated derivatives were evaluated for cardiotonic activity in vitro. Some of them showed weak positive inotropic effects and strong negative chronotropic effects. Thus, the presence of the 2'-hydroxyl group seemed to be essential for the appearance of potent positive inotropic activity caused by cAMP derivatives.

Acute effects of anticonvulsants on brain-stem auditory evoked potentials in rats

Acute effects of various anticonvulsants on brain-stem auditory evoked potentials (BAEPs) in rats were tested. A high dose of phenytoin abolished all BAEP waves. Carbamazepine increased all 4 wave latencies. Phenobarbital and clonazepam increased the latencies of waves IV and III. Therefore, if BAEPs are to be used as an ancillary test for brain death, the possibility of significant effects of high dosages of anticonvulsants on BAEPs must be considered.