3,4-dihydroxyphenylalanine (DOPA) decarboxylase deficiency and resultant high levels of plasma DOPA and dopamine in unfavorable neuroblastoma

Neuroblastoma (NB) is a tumor which arises from neural crest cells. In the developing neural crest cells, the induction of 3,4-dihydroxyphenylalanine (DOPA) decarboxylase is more delayed than that of tyrosine hydroxylase and dopamine-beta-hydroxylase. If NB cells are arrested in an early stage of neural crest development, the induction of DOPA decarboxylase is insufficient and the accumulation and secretion of DOPA can be caused. The biochemically immature phenotype is thought to represent the undifferentiated characteristics of the cells and might correlate with the grade of malignancy. To investigate whether the hypothesis is clinically applicable or not, we have measured plasma DOPA, dopamine and urinary catecholamine metabolites in NB patients. The levels of plasma DOPA, dopamine, urinary homovanillic acid (HVA) and vanillactic acid (VLA) were significantly higher in patients with unfavorable NBs and the higher plasma DOPA level was significantly associated with the patients' age (> 1 year old), tumor stage (III, IV) and DNA diploidy. Serial determination of plasma DOPA was a good monitor of the disease course. These results are compatible with the hypothesis on DOPA decarboxylase deficiency and DOPA secretion in undifferentiated, unfavorable NBs. In conclusion, the plasma DOPA can be used to predict patients' prognosis as well as to follow up patients with NB.

Caloric intake stimulates growth hormone secretion in food-deprived rats with anterolateral deafferentation of the medial basal hypothalamus or administered antiserum to somatostatin

In rats, food deprivation inhibits episodic growth hormone (GH) secretion. On the basis of previous studies, we hypothesized that during a recovery from prolonged fasting, caloric intake stimulates the release of GH-releasing factor (GRF) and this process does not depend on the specific macronutrients in the meal, while protein in the meal acts to restore characteristic ultradian rhythmicity of GH secretion. To test this hypothesis, the effect of caloric intake on GH secretion was examined in fasted adult male Wistar rats devoid of somatostatin (SS) influence on GH secretion either by anterolateral deafferentation (ALC) of the medial basal hypothalamus (MBH) or administration of anti-SS goat serum (ASS). Rats were provided with an indwelling right atrial cannula and were deprived of food for 72 h. ALC was performed 2 weeks prior to the study. ASS was given i.v. 8 h and 7 h prior to refeeding, respectively. Serial blood specimens were collected every 10 min. In rats with ALC (ALC rats) or rats given ASS (ASS rats), the blood GH level revealed irregularly occurring small fluctuations, instead of the usual high bursts and low trough level. The baseline GH level and the mean GH level of fasted ALC rats or fasted ASS rats were significantly lower than those of fed ALC rats or fed ASS rats. Feeding the isocaloric mixed meal, the protein meal or the protein-deficient meal increased the GH pulse frequency, the pulse amplitude, the baseline GH level and the mean GH level in 72-h fasted ALC rats. These changes in GH secretory pattern persisted during the period of observation and were independent of the type of meal ingested. Following feeding the mixed meal, similar changes in the GH secretory pattern demonstrated in 72-h fasted ALC rats were also observed in 72-h fasted ASS rats, suggesting that the stimulation of GH secretion following caloric intake is not limited to ALC rats. Since the influence of SS on GH secretion has been largely eliminated in ALC or ASS rats, it is highly unlikely that the augmentation of GH secretion following feeding after prolonged food deprivation was the consequence of inhibition of SS secretion. Although GRF measurement was not performed, it is conceivable that the signal of caloric intake is conveyed to the MBH and acts to stimulate GRF release.

Retrospective analysis of biological factors in a recurrent IV-S neuroblastoma with intermediate-grade malignancy

A clinical stage of IV-S neuroblastoma is known to include heterogeneous tumors. The authors report a case of IV-S neuroblastoma that relapsed after regression 4 years and 10 months after diagnosis. Multiagent chemotherapy was necessary to control the disease, and the patient has been doing well with no evidence of disease for more than 5 years. Although Shimada's classification showed favorable characteristics, N-myc protein was positive and DNA ploidy was diploidy in the tumor at diagnosis. Discrepancy in DNA ploidy was observed and aneuploidy was shown in tumor specimens at recurrence. Experience in this case showed the following important clinical features: (1) IV-S neuroblastoma of intermediate-grade malignancy does exist, and patients with such a disease may be cured by aggressive treatment; (2) Identifying IV-S patients with an unfavorable clinical course is possible by examining biological prognostic factors.

Amyloid beta protein 1-42/43 (A beta 1-42/43) in cerebellar diffuse plaques: enzyme-linked immunosorbent assay and immunocytochemical study

Diffuse plaques are immature and amorphous senile plaques and believed to be in the initial phase of plaque formation. In contrast to amyloid angiopathy and the plaque core amyloid, diffuse plaques failed to be purified in preserved forms from the brain. Here, we studied the diffuse plaques in the cerebellar region of the Alzheimer's disease brain based on immunocytochemistry and ELISA using two different monoclonal antibodies specifically recognizing the carboxyl termini of A beta molecules (BA27 for A beta 1-40 and BC05 for A beta 1-42/43). We found that the amount of A beta 1-40 was in proportion to the staining degree on amyloid angiopathy by immunohistochemistry. We found that A beta 1-42/43 comprised diffuse plaques as the major component in the cerebella of AD brains. Taking these findings into consideration, diffuse plaques, the earliest pathological change in the brain with AD, are concluded to be composed mainly of A beta 1-42/43, implicating the critical importance of this kind of A beta species deposition in the pathogenesis of AD.

Isolation and mapping of 186 new DNA markers on human chromosome 1

To obtain DNA markers on human chromosome 1, we first isolated 500 cosmid clones from mouse A9 cells containing a human chromosome 1 tagged with pSV2neo. Of these, 186 were localized on each band of human chromosome 1 by R-banding fluorescence in situ hybridization; 118 and 68 were on the short and long arms, respectively. We performed restriction fragment length polymorphism (RFLP) analysis of these cosmid clones, and polymorphism was recognized with one or more enzyme in 43 of them. Two markers proved to have variable numbers of tandem repeats. Since several tumor suppressor genes, as well as genes responsible for hereditary disorders, may be located on this human chromosome, the DNA markers will be useful for RFLP analysis or the isolation of new genes related to various disorders.

[The preventive effect of indeloxazine hydrochloride to the sexual dysfunction caused by anti-androgenergic agent (allylestrenol)]

Anti-androgenergic agents are usually used for patients with benign prostatic hypertrophy (BPH). However steroidal anti-androgenergic agents tend to suppress the sexual function. This side effect is very significant in middle-aged men. Therefore we studied the preventive effect of indeloxazine hydrochloride (INDX), which induces an increase of the dopamine level in the brain, on the sexual dysfunction induced by an anti-androgenergic agent (allylestrenol: ALE). Thirty-six patients with BPH were classified into two groups, one used ALE only, and the other ALE with INDX. For the subjective evaluation of the sexual function, a self assessment questionnaire method was employed before and after administration. We especially studied 3 questions, "morning erection", "erectile capacity" and "frequency of sex". For the objective evaluation of the sexual function, nocturnal penile tumescence (NPT) was measured using an erectometer. NPT occurs in healthy males as a physiological phenomenon and it shows the erectile capacity objectively. The levels of LH, total testosterone and free testosterone were also determined. In the ALE only group, sexual dysfunction was found subjectively and objectively, but in the ALE with INDX group, it was not found. Levels of LH, total testosterone and free testosterone were decreased in the both groups. There was no significant difference between the two groups. We hypothesized that the sexual dysfunction due to ALE is related with not only to the decrease of androgen, but also to suppression of the central nervous system; for example, the suppression of the area of the brain mediating sexual behavior.(ABSTRACT TRUNCATED AT 250 WORDS)

[Laboratory findings in patients with Yusho: 26 year follow-up study]

To evaluate chronic effect of PCBs on laboratory findings, peripheral blood cells and biochemical parameters were studied in 74 patients with Yusho in 1994. Serum level of triglyceride was elevated in 21 cases (28.4%) of these patients. Serum triglyceride levels showed statistically significant correlation with body mass index (Quetelet Index) and blood PCB concentration. We conclude that hypertriglyceridemia in patients with Yusho is not frequent and it may be associated with both obesity and blood PCB concentration.

[Impending rupture of a pseudoaneurysm in the descending thoracic aorta: a rare clinical course]

A sixty-year-old male manifested high fever, bloody sputa and an abnormal shadow in the left hilus on chest X-ray film. He was treated with antibiotics as for a infections lung disease. But back pain which he had been suffered from didn't improve. He was referred to the second hospital with suspicion of lung neoplasm. He underwent radiation therapy. The shadow in the left hilus had been increasing in size with the radiation therapy. On CT scanning, the shadow was recognized as an impending aneurysm along the descending thoracic aorta. He was referred to our hospital and operated upon in emergency basis. On operative findings, the aortic aneurysm located from the distal portion of the left common carotid artery and was huge sacklar shape. In surgical procedure, the entrance in the descending aorta was closed with a vascular patch graft because the aortic wall around the entrance was normal and unaffected. Postoperative course was uneventful. We should learn some warning from this case.

Mechanical measurements of single actomyosin motor force

To elucidate the mechanism of force generation by actomyosin motor, a measuring system was constructed, in which an in vitro motility assay was combined with an optical trapping technique. An actin filament of several micron long was attached to a gelsolin-coated polystyrene bead, and was allowed to interact with a small number (approximately 1/1 micron actin filament) of rabbit skeletal heavy meromyosin (an active subfragment of myosin) molecules bound to a nitrocellulose-coated coverglass. The bead position was determined at 33-ms intervals. We measured the force generation event at relatively low (100-400 nM) ATP concentration so that the occurrence of individual force generation events could be detected with our time resolution. The actin-bound bead held in the optical trap moved in a stepwise manner in the direction of the actin filament only in the presence of ATP. At the trap strength of 0.3 pN/nm, the maximum size of the step was 11 nm, and the maximum force associated with the movement was 3.3 pN.

Extraction of water-soluble vitamins from pharmaceutical preparations using AOT (sodium di-2-ethylhexyl sulfosuccinate)/pentane reversed micelles

Reversed micelles can be used to concentrate water-soluble materials in the water pool. In this study, the extraction of water-soluble vitamins into reversed micelles was attempted, and a flow system was used to determine the time-course of the vitamin extraction. The efficiency of extraction was strongly affected by the extraction temperature and the concentration of reversed micelles, and the selectivity depended on the size of micelles. Water-soluble vitamins could be efficiently and rapidly extracted. The selective extraction of a model mixture of vitamins from pharmaceutical preparations was also attempted. Moreover, the usefulness of the proposed method for the determination of vitamins in various commercial tablets was also demonstrated. Using of this method, the surfactant remains mixed with the extracted compounds, and so we attempted to remove the surfactant from the extract by supercritical fluid extraction. Supercritical carbon dioxide containing 7.5% ethanol as entrainer was found to be the most efficient solvent for removing residual surfactant from the extract.

[Risk of chromosomally unbalanced progeny in prenatal diagnoses of reciprocal translocation carrier]

To obtain new criteria for presuming the existence of chromosomally unbalanced progeny in reciprocal translocation carrier couples, the obstetrical histories of 57 couples were analysed. The chromosomally unbalanced progeny who had been prenatally or postnatally diagnosed were mainly partial trisomies. In contrast with partial trisomies, there were only a few cases of partial monosomies and there were only two cases of chromosomal imbalance derived from 3:1 segregation in gametogenesis. Moreover, the percentage of haploid autosome length (%HAL) of the maternal carriers whose progeny had suffered from chromosomal imbalance was significantly smaller than those of the maternal carriers who had not had progeny with chromosomal imbalance. Based on these results, the following criteria were obtained: 1) Partial trisomies tend to be maintained in pregnancy but partial monosomies do not; Most chromosomally unbalanced zygotes which were induced by 3:1 segregated gametes tend to be spontaneously selected in early pregnancy; 3) When interchanged segments of chromosomes are small in maternal reciprocal translocation carriers, chromosomally unbalanced fetuses tend to be maintained in pregnancy.

Induction of ductal carcinomas by intraductal administration of 7,12-dimethylbenz(a)anthracene in Wistar rats

Postpartum Wistar inbred rats (weaned on the 9th puerperal day) were injected intraductally in one mammary gland with 7,12-dimethylbenze (a) anthracene (DMBA) to selectively induce ductal carcinoma. The incidence of ductal hyperplasia increased with time until it peaked at 7 weeks (12/13 animals) and then decreased. Ductal carcinoma first developed at 9 weeks in 3/12 (2 non-invasive and 1 invasive lesion) and the incidence increased with time until invasive ductal tumors were observed in 9/11 at 20 weeks. Tumors developed only in the DMBA-treated mammary glands and no systemic effects of the carcinogen were observed. Degeneration and detachment of epithelioglandular cells were seen here and there in the ducts and terminal ducts, and epithelioglandular cells proliferated in terminal duct until 2 weeks. Residual trace DMBA powder was detected in terminal ducts and the epithelioglandular layer until 7 weeks. This trace DMBA was considered to be the cause of the development of atypical epithelial cells, inducing ductal carcinomas.

Amyloid beta protein (A beta) in Alzheimer's disease brain. Biochemical and immunocytochemical analysis with antibodies specific for forms ending at A beta 40 or A beta 42(43)

Biochemical and immunocytochemical analyses were performed to evaluate the composition of the amyloid beta protein (A beta) deposited in the brains of patients with Alzheimer's disease (AD). To quantitate all A beta s present, cerebral cortex was homogenized in 70% formic acid, and the supernatant was analyzed by sandwich enzyme-linked immunoabsorbent assays specific for various forms of A beta. In 9 of 27 AD brains examined, there was minimal congophilic angiopathy and virtually all A beta (96%) ended at A beta 42(43). The other 18 AD brains contained increasing amounts of A beta ending at A beta 40. From this set, 6 brains with substantial congophilic angiopathy were separately analyzed. In these brains, the amount of A beta ending at A beta 42(43) was much the same as in brains with minimal congophilic angiopathy, but a large amount of A beta ending at A beta 40 (76% of total A beta) was also present. Immunocytochemical analysis with monoclonal antibodies selective for A beta s ending at A beta 42(43) or A beta 40 confirmed that, in brains with minimal congophilic angiopathy, virtually all A beta is A beta ending at A beta 42(43) and showed that this A beta is deposited in senile plaques of all types. In the remaining AD brains, A beta 42(43) was deposited in a similar fashion in plaques, but, in addition, widely varying amounts of A beta ending at A beta 40 were deposited, primarily in blood vessel walls, where some A beta ending at A beta 42(43) was also present. These observations indicate that A beta s ending at A beta 42(43), which are a minor component of the A beta in human cerebrospinal fluid and plasma, are critically important in AD where they deposit selectively in plaques of all kinds.

Carbamazepine-induced thrombocytopenia and carbamazepine-10,11-epoxide: a case report

The case of a patient who developed thrombocytopenia during treatment with carbamazepine (CBZ) is described. The platelet count recovered soon after discontinuation of CBZ, Lymphocyte stimulation test with carbamazepine-10, 11-epoxide (CBZ-10, 11-EPOX), a major metabolite of CBZ, was positive, although with CBZ it was negative. These findings suggest that CBZ-10, 11-EPOX was possibly causative in the pathogenesis of CBZ-induced thrombocytopenia in this case.

Amyloid beta protein (A beta) deposition: A beta 42(43) precedes A beta 40 in Down syndrome

The chronological relationship regarding deposition of amyloid beta protein (A beta) species, A beta 40 and A beta 42(43), was investigated in 16 brains from Down syndrome patients aged 31 to 64 years. The frontal cortex was probed with two end-specific monoclonals that recognize A beta 40 or A beta 42(43). All senile plaques detected with an authentic beta monoclonal were also A beta 42(43) positive, but only a varying proportion was A beta 40 positive. In young (< or = 50 years old) brains there were many A beta 42(43)-positive, A beta 40-negative diffuse plaques, but only few A beta 40-positive senile plaques (mean, 6.3% of total number of senile plaques). The 2 youngest Down syndrome brains showed only diffuse plaques that were all A beta 42(43) positive but A beta 40 negative. Old (> 50 years old) brains contained many mature senile plaques with amyloid cores in addition to diffuse and immature plaques and the proportion of A beta 40-positive senile plaques was increased (mean, 42% of total). Cerebral amyloid angiopathy was more abundant in old Down syndrome brains and was positive for both A beta 40 and A beta 42(43). In cerebral amyloid angiopathy, A beta 40 predominated over A beta 42(43) in both staining intensity and number of positive vessels. These results indicate that (1) the A beta species initially deposited in the brain as senile plaques is A beta 42(43) and A beta 40 only appears a decade later, and (2) in cerebral amyloid angiopathy A beta 40 appears as early as A beta 42(43).

Further application and evaluation of critical cell number and modifying factors in radiocurability of multicellular spheroids

Relationship of cure and surviving clonogenic cell number after various doses of X-irradiation was examined in multicellular spheroids of LCT1 human lung adenocarcinoma cells, LCT2 human lung small cell carcinoma cells and FSA1233 mouse fibrosarcoma cells. Some of these spheroids were cured at such doses that considerable number of clonogenic cells still survived after irradiation. Radiocurability was analyzed by comparing total clonogenic cell number in spheroids, cellular radiosensitivity and critical cell number Nc, i.e., the minimum number of clonogenic cells required to produce regrowth. (Nc-1) cells were killed by post-radiation processes and the larger the critical cell number, the more radiocurable. The LCT2 spheroids had the largest critical cell number and were most radiocurable. To investigate underlying mechanisms, modifying effect of heavily irradiated (HIR) tumor cells on the clonogenicity, i.e., plating efficiency of unirradiated tumor cells was investigated. Plating efficiencies with HIR cells showed significant decrease in LCT2 cells, no change in LCT1 cells and increase in FSA1233 cells. The results indicated that in case of LCT2 spheroids some of viable cells surrounded by dying or dead cells might have been killed with unknown toxic effect additional to direct irradiation effect. Thus, critical cell number analysis may be useful to quantify and to compare modifying effect of cellular/environmental factors in curing process of spheroids or tumors.

Carbamazepine-exacerbated epilepsy with multifocal shifting independent epileptiform discharges on electroencephalogram: a case report

A 7 year old girl with epilepsy and spastic quadriplegia secondary to an episode of status epilepticus at 4 months of age is reported. At the age of 6 years, she began to experience increased generalized myoclonic and tonic seizures during treatment with carbamazepine (CBZ) 200 mg/day and clonazepam 1.5 mg/day. When the CBZ was increased to 400 mg/day, the seizures increased dramatically in frequency. Following discontinuation of CBZ, the seizure frequency decreased to a level less than that prior to starting CBZ. Serial electroencephalograms displayed multifocal independent epileptiform discharges (MIED) characterized by shifting localization, which could be one of the risk factors for exacerbation by CBZ. In this case MIED may indicate widespread rather than localized cerebral dysfunction.

Isoenzyme patterns of glucose-6-phosphate dehydrogenase, malate dehydrogenase and lactate dehydrogenase in Babesia rodhaini and Babesia microti

Glucose-6-phosphate dehydrogenase (G6PD), malate dehydrogenase (MDH), and lactate dehydrogenase (LDH) activities and their isoenzyme patterns in B. rodhaini (BR) and B. microti (BM), the two major causative species of murine babesiosis, were examined. G6PD and LDH activities were higher in BR than those in BM, whereas MDH activity was lower in BR than that in BM. No differences were observed between BR and BM in the mobility of isoenzyme bands of G6PD and MDH. On LDH isoenzyme pattern, at least 5 bands were detected in BR, while only one band in BM. Since each subunit of LDH is known to be coded by different gene, these results suggests that BR and BM are able to be differentiated genetically.

Low serum levels of dehydroepiandrosterone may cause deficient IL-2 production by lymphocytes in patients with systemic lupus erythematosus (SLE)

The principal cause of IL-2 deficiency, a common feature of both murine lupus and human SLE, remains obscure. Recent studies of our own as well as others have shown that dehydroepiandrosterone (DHEA), an intermediate compound in testosterone synthesis, significantly up-regulates IL-2 production of T cells, and that administration of exogenous DHEA or IL-2 via a vaccinia construct to murine lupus dramatically reverses their clinical autoimmune diseases. Thus, we have examined serum levels of DHEA in patients with SLE to test whether abnormal DHEA activity is associated with IL-2 deficiency of the patients. We found that nearly all of the patients examined have very low levels of serum DHEA. The decreased DHEA levels were not simply a reflection of a long term corticosteroid treatment which may cause adrenal atrophy, since serum samples drawn at the onset of disease, which are devoid of corticosteroid treatment, also contained low levels of DHEA. In addition, exogenous DHEA restored impaired IL-2 production of T cells from patients with SLE in vitro. These results indicate that defects of IL-2 synthesis of patients with SLE are at least in part due to the low DHEA activity in the serum.

[A study on the erectile response with the vacuum constriction device compared with intracavernous injection of a vasoactive drug]

Many types of vacuum constriction devices (VCDs) are used for the treatment of impotence, but the VCDs made in the USA are too large for Japanese males, and air leakage occurs. Therefore, we examined the erectile response of 47 impotent men to a vacuum constriction device that is made in Japan and can be applied suitably for Japanese men, and compared the response to intracavernous injection of prostaglandin E1 (PGE1). When the 47 cases were divided into two groups by nocturnal penile tumescence, twenty of the impotent men were regarded to have fewer organic factor (group A) while 27 were regarded to have more organic factor (group B). All (100%) of the 20 cases of group A achieved a complete erection with the VCD, but only 11 (55%) of them achieved a complete erection with PGE1. Twenty-three (85%) of the 27 cases of group B achieved a complete erection with the VCD, but only nine (33%) achieved a complete erection with PGE1. Two of the four patients who did not achieve a complete erection with the VCD stopped pumping the VCD because of penile pain, and the other two patients had a penile-brachial pressure index (PBPI) of under 0.65. It was suggested that patients with no severe vascular disease can show a good erectile response with the VCD.

Reduction of unscheduled DNA synthesis and plasminogen activator activity in Hutchinson-Gilford fibroblasts during passaging in vitro: partial correction by interferon-beta

Two fibroblast cell lines (PG3KT and PG1NA) derived from Hutchinson-Gilford syndrome (progeria) cases were characterized, at various population doubling levels (PDL), with respect to the capacity of ultraviolet light (UV, mainly 254 nm wavelength)-induced unscheduled DNA synthesis (UDS) and plasminogen activator-like protease activity (PA). The UDS levels in PG3KT and PG1NA cells at PDL 2-3 were only slightly less than those in normal fibroblasts. With increasing PDL, both progeria cell lines exhibited reduction of the UDS levels and undetectable ones at PDL 9-11. Prompt and transient induction of PA was also detectable at less than PDL 5, whereas it was undectable at higher PDL. However, the levels of UDS and PA induction were increased about 3-7 times after pretreatment with 100 IU/ml human interferon (HuIFN)-beta preparations for more than 24 h prior to UV irradiation, although UDS and PA were undetectable at more than PDL 10. These results suggest that cytokines such as HuIFN-beta transiently compensate for the decreases in UDS and PA inducibility in progeria cells with aging.

Structure, function and biosynthesis of sperm-activating peptides and fucose sulfate glycoconjugate in the extracellular coat of sea urchin eggs

A decapeptide (GFDLNGGGVG) isolated from the solubilized jelly layer of the sea urchin Hemicentrotus pulcherrimus stimulates the respiration and motility of H. pulcherrimus spermatozoa and, in addition, produces a number of biological effects on H. pulcherrimus spermatozoa including increases in cAMP and cGMP levels, activation of a Na+/H+ exchange system, and increases in intracellular pH (pHi) and [Ca2+] ([Ca2+]i). The peptide activates the metabolism of endogenous phosphatidylcholine and promotes the acrosome reaction as a specific co-factor of a major acrosome reaction-inducing substance, fucose sulfate glycoconjugate. The peptide also induces an electrophoretic mobility change in the guanylate cyclase of the sperm plasma membrane with concomitant dephosphorylation and inactivation of the enzyme. Seventy-four peptides producing similar biological effects, named sperm-activating peptide (SAP), have since been purified from the solubilized jelly layer of seventeen species of sea urchins distributed over five taxonomic orders. These peptides show essentially the same biological effects on sea urchin spermatozoa although their activity and structures are specific at the ordinal level. Equilibrium binding experiments using a radioiodinated SAP-I analogue [GGGY(125I)GFDLNGGGVG] to H. pulcherrimus spermatozoa suggests the presence of two classes of receptors (high affinity and low affinity) specific for SAP-I binding. Based on the Kd values and EC50's for SAP-I's biological activity, we presume that the high affinity receptor is associated with respiration-stimulating activity and elevations in pHi, while the low affinity receptor is coupled to elevations in cGMP and [Ca2+]i. The radioiodinated SAP-I analogue crosslinks to a 71 kDa protein which contains a single membrane-spanning domain at almost near C-terminus. A SAP-I precursor which is synthesized in the accessory cells contains five SAP-I and seven SAP-I-like decapeptides, each separated by a single lysine residue.

Induction of differentiation into monocyte/macrophage cell lineage of a human eosinophilic leukaemia cell line EoL-1 by simultaneous stimulation with tumour necrosis factor-alpha and interferon-gamma

Human myeloid leukaemia cell lines have been shown to differentiate into distinct cell lineages in vitro in response to several differentiation-inducing agents. A human eosinophilic leukaemia cell line, EoL-1, has been shown to differentiate into mature eosinophilic granulocytes by treatment with the culture supernatant of a human T-cell line, HIL-3. In this study we have studied whether the EoL-1 cell line has potential to differentiate into cell lineage other than eosinophils. We found that EoL-1 cells cultured in the presence of tumour necrosis factor (TNF)-alpha (10 u/ml) and interferon (IFN)-gamma (1000 u/ml) for 2-4 d differentiated into macrophage-like cells in morphology, and expressed CD14 antigen on their cell surface. It is possible that the small subpopulation of EoL-1 cells which contains non-specific esterase (NSE) activity may be preferentially differentiated by TNF-alpha and IFN-gamma. To clarify this issue, we have cloned the EoL-1 cell line and obtained NSE negative and positive sublines. Both EoL-1 sublines differentiated into monocyte/macrophage-like cells, because: (a) EoL-1 sublines were induced to express CD14 antigen, and (b) they attached firmly to the plastic wells; (c) after differentiation they became strongly positive for NSE staining, and secreted TNF-alpha in response to the stimulation with lipopolysaccharide; and (d) they exhibited potent phagocytic activity. Therefore, we found that the EoL-1 cell line has the ability to differentiate not only into mature eosinophilic cells but also into monocyte/macrophage cell lineage, suggesting that EoL-1 cells represent immature cells with ability to differentiate into multiple cell lineages.