Thyroid hormone affects the gene expression of retinoid X receptors in the adult rat

Gene expression of three nuclear retinoid X receptors (RXR alpha, beta and gamma) was examined by Northern blot analysis in various rat tissues. The RXR alpha mRNA (5.5 kb) was detected in most tissues and particularly expressed at a high level in the liver. The RXR beta transcripts (2.4 and 3.0 kb) were expressed ubiquitously, and particularly at high levels in the brain and testis. In the liver, heart, kidney and lung, the RXR gamma mRNA (2.0 kb) was specifically detected. Furthermore, we examined the effect of retinoid, vitamin D and thyroid hormone status on the gene expression of RXR alpha, beta and gamma. Though retinoid and vitamin D did not affect the mRNA levels of three RXRs, the mRNA levels of two genes were controlled by thyroid hormone. Namely, positive (RXR beta) and negative (RXR gamma) regulations by thyroid hormone were observed with no effect on the gene expression of RXR alpha. These results suggest that thyroid hormone might affect the signal transduction of retinoid, vitamin D and thyroid hormone by changing RXR levels.

Expression of a novel form of Tec kinase in hematopoietic cells and mapping of the gene to chromosome 5 near Kit

The Tec kinase was initially identified as a novel cytoplasmic protein tyrosine kinase that is preferentially expressed in the liver and is highly homologous to the Drosophila Dsrc28C src-related tyrosine kinase. In screening of interleukin 3 (IL-3)-dependent myeloid leukemia cells for protein tyrosine kinases, we observed that all cell lines examined expressed high levels of Tec transcripts. However, characterization of Tec cDNAs indicated that they differed significantly from the published sequence. Most strikingly, an insertion of 41 bp in the 5' region affects the initiation codon and results in replacing the published 13 amino acid amino-terminal sequences with 94 amino acids. Using polymerase chain reaction (PCR) analysis, only the form containing the insertion was detected in hematopoietic cells. In addition, we found an in-frame insertion of 66 bp that introduces an additional 22 amino acids into the SH3 domain. This insertion restores conserved SH3 sequences that are found in the src gene family and in the Dsrc28C gene. By PCR analysis, approximately equal levels of Tec transcripts containing the intact SH3 domain and containing the 22 amino acid deletion were found in hematopoietic cells. Lastly, by interspecies backcross analysis, we show that the Tec gene is tightly linked to the c-Kit gene on mouse chromosome 5.

Effect of retinoid status on alpha, beta and gamma retinoic acid receptor mRNA levels in various rat tissues

We have investigated the effects of retinoids, vitamin D and thyroid hormone on the levels of retinoic acid receptor (RAR)alpha, RAR beta and RAR gamma mRNAs in intact animals. Although vitamin A deficiency caused no significant changes in the levels of RAR alpha and RAR gamma mRNAs, the level of RAR beta transcripts was greatly decreased in various tissues of vitamin A-deficient rats, but was restored rapidly to a normal level after administration of retinoic acid. Retinol also restored the RAR beta mRNA level, but the magnitude and kinetics of the induction differed from those by retinoic acid. The use of specific inhibitors demonstrated that this autoregulation of RAR beta gene expression in vivo occurred at the transcriptional level. In addition, from these results it was postulated that the maintenance of the normal RAR beta mRNA levels seemed to require a threshold serum retinol concentration (about 25 micrograms/dl). Moreover, we found that administration of retinol and retinoic acid to normal rats caused the overexpression of RAR beta transcripts (2-15-fold) when compared with the control levels of RAR beta mRNA, although the levels of RAR alpha and RAR gamma mRNAs were not affected. Vitamin D and thyroid hormone did not modulate the levels of RAR transcripts. These findings clearly indicate the specific ligand regulation of RAR beta gene expression in intact animals. The altered levels of RAR beta according to retinoid status may affect retinoid-inducible gene expression.

Prophylactic effect of bestatin on the onset of invasive mole--clinical and fundamental studies

This study was performed to determine whether bestatin (Ubenimex) has clinical prophylactic effects on the onset of invasive mole and a direct inhibitory effect on the growth of hydatidiform molar cells. A total of 49 patients with hydatidiform mole treated at Nagoya University Hospital from 1984 to 1990 were randomly divided into two groups, a bestatin administered-group and a bestatin non-administered group. Patients in the bestatin group were given 30 mg of bestatin orally and daily for three months just after their molar deliveries. There was no significant difference in age, gravidity, parity and gestational weeks between the two groups. There was also no significant difference in the duration of human chorionic gonadotropin (hCG) negative conversion in patients without invasive mole between the two groups. However, the incidence of invasive mole in the bestatin group (2/25, 8%) was significantly lower than that of the non-bestatin group (7/24, 29.2%). Nevertheless, there was no significant difference between the two groups in such immunological parameters as PHA skin test, PPD skin test, PHA stimulation index (PHA-SI), white blood cell (WBC) count lymphocytes % per WBC, OKT 3% per lymphocytes, OKT 4% per lymphocytes, OKT4/OKT8 and Leu 11% per lymphocytes. In vitro studies were performed with primary cultured hydatidiform moles. The result was that bestatin inhibited the secretion of hCG and 3H-thymidine uptake of hydatidiform molar cells. Thus, a possibility was suggested that bestatin directly inhibits the growth of hydatidiform molar cells and prevents the onset of invasive mole.

Acute toxicity of tri-n-butyltin chloride (TBTC) in the Syrian golden hamster

The effects of tri-n-butyltin chloride (TBTC) on Syrian golden hamsters were studied. TBTC in single doses of 0, 29.6, 44.4, 66.7, 100 or 150 mg/kg were given to 10 male hamsters in each group and the mortality rates were determined two weeks thereafter. They were 0% (0/10), 0% (0/10), 10% (1/10), 10% (1/10), 30% (3/10) and 70% (7/10) for 0, 29.6, 44.4, 66.7, 100 and 150 mg/kg groups, respectively. In the case of females, seven groups consisting of 10 animals each were given TBTC at doses of 0, 29.6, 44.4, 66.7, 100, 150, or 225 mg/kg. The mortality rates determined two weeks after the TBTC treatment were 0% (0/10), 10% (1/10), 10% (1/10), 0% (0/10), 40% (4/10), 30% (3/10) and 90% (9/10) for 0, 29.6, 44.4, 66.7, 100, and 225 mg/kg groups, respectively. Based on these mortality data, the LD50s via oral administration were determined as 146.9 mg/kg (95% C.I. 111.8-193.3 mg/kg) for the male and 172 mg/kg (95% C.I. 127.2-233.4 mg/kg) for the female. Regarding pathological changes, animals experienced lesions in the bile duct, such as the dilatation of the common bile duct and cholestasis, and/or adhesion of the bile duct to the liver, gallbladder, pancreas and duodenum. In a separate experiment, a single dose of 44.4 mg/kg TBTC was administered orally to 12 male hamsters, then the concentrations of TBTC and its metabolite, di-n-butyltin chloride (DBTC), in the liver were analyzed by means of gas chromatography for 14 days after the treatment. The maximum concentrations of TBTC and DBTC appeared one day after the administration, and decreased rapidly thereafter. The concentration of DBTC was found to be higher than that of TBTC throughout the experimental period.

Identification of a soluble GM-CSF binding protein in the supernatant of a human choriocarcinoma cell line

We identified two forms of the receptor for granulocyte-macrophage colony-stimulating factor (GM-CSF) made by the human choriocarcinoma cell line JEG-3 using an affinity-labeling technique. The protein was identified in the detergent-extract was 78 kDa, very similar to that of the membrane-bound GM-CSF receptor alpha chain expressed in a wide variety of hematopoietic and nonhematopoietic cells, including JEG-3. In contrast, a 62-kDa GM-CSF binding protein, or the soluble GM-CSF receptor, was identified in the supernatant of JEG-3 cells. Utilizing the same affinity labeling technique, we did not detect the soluble GM-CSF binding protein in the supernatant of several hematopoietic cell lines, such as U-937 and KG-1, which express membrane bound alpha chain as well as beta chain. The 62-kDa soluble GM-CSF receptor is produced in abundant amounts by JEG-3, but in very small amounts, if any, by hematopoietic cell lines.

The Structure and Intensity of Emotional Experiences: Method and Context Convergence

This article investigates the structure and intensity of naturally-occurring and induced affect using two different methodological paradigms, dimensionality and classification, and two different everyday contexts. The analyses revealed that the structures of feelings experienced during a lecture (naturally-occurring affect) and after exposure to TV ads (induced affect) are similar and can be described as points on a circumplex determined by Pleasantness and Arousal. Based on this circular structure, a synthesis aimed at describing the intensities of affective experiences is offered. Implications for the study of the structure of affect are discussed.

Cytogenetic analysis of human bile for mutagenicity and co-mutagenicity

Cytogenetic analysis was used to test whether or not human bile induced chromosome abnormalities in lymphocytes grown in culture. Bile was obtained from gallbladders resected for various reasons such as cholecystitis, cholelithiasis, polypus and cancers of the biliary tract, stomach and pancreas. After adding human bile to a final concentration of 25 microliters/ml or 12.5 microliters/ml, the culture medium was incubated at 37 degrees C for 72 hr. Air-dried slides were stained with conventional Giemsa and the numerical and structural chromosome abnormalities were scored. Positive and negative controls in terms of chromosome abnormalities were established by using 0.03 micrograms/ml mitomycin C (MMC) and 0.9% normal saline, respectively. Cytogenetic analysis was successfully performed in 6 out of 10 bile samples (60.0%). Bile alone did not induce numerical or structural chromosome abnormalities. Structural abnormalities increased significantly in the 25 microliters/ml bile + 0.03 micrograms/ml MMC group, compared with the 0.03 micrograms/ml MMC group: 36.0% vs. 20.7% in the chromatid-type gaps and breaks, 27.8% vs. 22.7% in the chromosome-type gaps and breaks, and 8.3% vs. 3.2% in the exchange-type abnormalities. It is likely that the interaction between bile and MMC is synergistic rather than additive.

Replication of human immunodeficiency virus type 1 in primary cultured placental cells

The role of placental cells in transplacental transmission of human immunodeficiency virus type 1 (HIV 1) was investigated. Placental macrophages and trophoblasts, which together represent the main cell components of the placenta, were cultivated separately and then compared to foetal monocyte-derived macrophages for susceptibility to HIV 1 infection. Placental macrophages treated with granulocyte-macrophage colony-stimulating factor (GM-CSF) were less easily infected with HIV 1 than were GM-CSF-treated foetal monocyte-derived macrophages. HIV 1 replication in cocultures consisting of infected placental macrophages together with a highly HIV 1-permissive cell line (CEM) was detected persistently for at least 6 weeks by reverse transcriptase assay, even though placental macrophages expressed no detectable CD4 receptor, as indicated by indirect immunofluorescence. HIV 1-specific DNA sequences were also detected in infected placental macrophages. Trophoblasts exhibited no detectable CD4 expression and did not support the replication of HIV 1, although low levels of HIV 1-specific DNA sequences could be detected in infected trophoblasts. Placental macrophages or trophoblasts (or both) may thus play an important role in transplacental HIV 1 transmission.

Fetal human immunodeficiency virus type 1 infection of different organs in the second trimester

Human immunodeficiency virus type 1 (HIV-1) infection in utero was examined by isolating the virus and detecting the HIV-1 DNA sequence from different fetal tissues. The brain, thymus, lung, liver, spleen, and placenta tissues from fetuses (10-23 weeks of gestation) born to HIV-1-infected asymptomatic mothers were examined. HIV-1 was isolated from 2 of 7, 1 of 7, and 1 of 7 cocultures of splenic, thymic, and trypsin-resistant cells from the liver and placenta, respectively, with peripheral blood mononuclear cells; 20-30% and 40-60% of splenic and of thymic cells were CD4+ lymphoid cells and 40-80% of trypsin-resistant cells were mononuclear phagocytes. The HIV-1 DNA sequence was detected in 4 of 7, 3 of 7, 1 of 7, 1 of 7, 2 of 7, and 2 of 6 samples from the spleen, thymus, brain, lung, liver, and placenta, respectively, using the polymerase chain reaction. In one case, the intensity of the HIV-1 DNA sequence appeared to be correlated with the success of viral isolation. We indicate that fetal HIV-1 infection may frequently occur in the second trimester and the cells responsible for the infection may be CD4+ lymphoid cells and mononuclear phagocytes.

A novel protein-tyrosine kinase, tec, is preferentially expressed in liver

To identify protein-tyrosine kinases which play an important role in the process of hepatocarcinogenesis, we have screened a murine liver cDNA library with v-fps kinase domain as a probe. Using low stringency screening, we could isolate cDNAs of a putative protein-tyrosine kinase, tec (tyrosine kinase expressed in hepatocellular carcinoma). Nucleotide sequences of the cDNAs show that the C-terminal domain of its predicted protein has significant homology with that of the members of the src family. The tec gene is expressed mainly in liver and faintly in heart, kidney and ovary. Northern analysis further shows that in 2 out of 4 cell lines of human hepatocellular carcinoma (HCC) the tec gene is highly expressed compared to normal human liver. This is the first report showing a protein-tyrosine kinase which may be specifically involved in the cell growth of hepatocytes or in the step of hepatocarcinogenesis.

Expression of human placenta alkaline phosphatase in placenta during pregnancy

To clarify the expression of PLAP during the course of pregnancy, the amount of PLAP mRNA and its activity in normal placental villi were measured. Both PLAP and its mRNA were found in placentae of as early as 7 weeks of gestation, and they continued to increase throughout pregnancy. But they showed different patterns of increase. The amount of PLAP mRNA began to increase dramatically around 13th week and probably continued to increase gradually until term. PLAP activity per gram of villi showed a gradual increase from around 13th week and a marked increase was observed after about 20th week. PLAP levels in sera from pregnant women were also measured, and they showed a pattern of increase imilar to that of PLAP activity per gram of villi. The continuous increase in the expression of PLAP throughout pregnancy suggests that PLAP may play a role in feto-maternal metabolism and placental differentiation.

Selenium contents in human gallbladder bile

The selenium contents in human gallbladder bile were analyzed. Thirty-seven subjects were studied; 22 patients with cholelithiasis in Niigata Prefecture and 15 patients (13 with cholelithiasis and 2 with gallbladder polypus) in Kochi Prefecture. Five ml of bile was withdrawn with a syringe from the gallbladder during the operation and stored at -20 degrees C until analysis. For the analysis by gas chromatograph with an electron-capture detector, 0.2 ml of sample was used. The mean selenium contents in bile were 269 +/- 39.0 (mean +/- S.D.) ng/ml for the subjects in Niigata and 285 +/- 84.4 ng/ml in Kochi; without significant difference. Of 37 samples analyzed, the mean content was 276 +/- 61.0 ng/ml.

Establishment of hybridomas secreting monoclonal antibodies to placental alkaline phosphatase and development of an enzyme immunoassay for its determination

We established seven hybridomas secreting murine IgG monoclonal antibodies (MoAbs) to placental alkaline phosphatase (PLAP). The seven hybridomas were designated (1) 7C6, (2) 6G10, (3) 5B9, (4) 6D5, (5) 6B5, (6) 11G6 and (7) 3E10, respectively. The characteristics of these hybridomas were evaluated by radioimmunoassay (RIA) with 125I-PLAP. Their reactivity with the intestinal alkaline phosphatase, one of the alkaline phosphatase isozymes, was (1) 0.04, (2) 0.2, (3) 1.4, (4) 1.8, (5) 0, (6) 4.0 and (7) 6.2(%), respectively. None of them showed signs of cross-reactivity with the liver-type alkaline phosphatase, also one of the alkaline phosphatase isozymes, within a PLAP concentration of 2,000 IU/l. The subtype of 5B9 was IgG1, and that of the others was IgG2a. We then used 7C6, to develop a sensitive, specific and convenient enzyme immunoassay (EIA) for the determination of PLAP, and assayed sera from patients with various gynecologic diseases. The incidence of increased PLAP was 6.4% in patients with benign diseases, 21.5% in cervical cancer, 36.4% in endometrial carcinoma, and 39.5% in malignant ovarian tumors. The specificity for malignant diseases seemed to be higher than that of CA125. Among endometrial carcinomas, well-differentiated adenocarcinoma had the highest incidence of an increased concentration. Among malignant ovarian tumors, serous cystadenocarcinoma, endometrioid carcinoma, dysgerminoma and Krukenberg's tumor showed a higher incidence than the other types.

Invasive character of malignant endothelial cells in vinyl-chloride-induced liver angiosarcoma

Two cases of vinyl-chloride-induced angiosarcoma of the liver were investigated with special reference to the invasive character of malignant endothelial cells. Histological findings of the liver were similar in both cases. The liver angiosarcoma was multicentric and consisted of three portions: a peripheral parenchymal area, an intermediate mottled area, and a central cavernous area. Microscopically the intermediate area showed a mixture of fibrosis and cell infiltration of various patterns. At the periphery, yellowish brown parenchymal tissues remained and were always associated with sinusoidal changes, from non-cellular dilatation to trabecular growth of the small round cells. Under electron microscope, the small round cells showed direct contact with red blood cells and hepatocytes. Thus, the sinusoidal small cell infiltration is thought to be an initial lesion of angiosarcomatous transformation. Because none of the liver is free from these sinusoidal changes, partial hepatectomy would not be indicated even in a patient with few cavernous lesions.

Paraneoplastic syndrome of hypercalcemia and leukocytosis caused by squamous carcinoma cells (T3M-1) producing parathyroid hormone-related protein, interleukin 1 alpha, and granulocyte colony-stimulating factor

Previously we reported that a clonal squamous cell carcinoma cell line (T3M-1) derived from a lower jaw cancer of a patient with marked leukocytosis and hypercalcemia produced factors containing a potent bone-resorbing activity (BRA) (Mr 15,000-20,000) and a colony-stimulating activity. To elucidate the pathogenesis of this humoral hypercalcemia, BRA and colony-stimulating activity in both the conditioned medium and cells were characterized. The conditioned medium, when eluted at neutral pH, contained colony-stimulating activity and thymocyte proliferation-stimulating activity, the latter of which comigrated with BRA. Upon elution with acetic acid (pH 2.0), the conditioned medium contained no interleukin 1-like activity but potent parathyroid hormone-like activity, which comigrated with BRA. Northern blot hydridization analysis revealed that T3M-1 cells produced constitutively mRNA for parathyroid hormone-related protein and granulocyte colony-stimulating factor. Furthermore, primer extension analysis revealed that the cells also produced mRNA for interleukin 1 alpha (IL-1 alpha). Since parathyroid hormone-related protein and IL-1 alpha (osteoclast-activating factor) synergistically increase the concentration of serum calcium, and since IL-1 alpha (hemopoietin 1) potentiates granulocyte colony-stimulating factor-induced granulocytopoiesis, we speculate that parathyroid hormone-related protein, granulocyte colony-stimulating factor, and IL-1 alpha are synergistically involved in a paraneoplastic syndrome of hypercalcemia and leukocytosis, at least in some patients with solid tumors.

Mutations of N-ras oncogene in myelodysplastic syndromes and leukemias detected by polymerase chain reaction

By using polymerase chain reaction and differential hybridization, point mutations of N-ras oncogene were investigated among 43 patients with hematopoietic malignancies. Six cases were revealed to carry mutational N-ras oncogenes. One case with acute myelocytic leukemia was found to carry a mutation at codon 13, although this case was in complete remission.

Analysis of the mechanism of influenza B virus inactivation by guinea pig serum

Normal guinea pig serum lacking detectable antiviral antibody inactivated influenza B virus via the classical complement pathway. This virus inactivation appeared to result from the steric hindrance of HA activity by the association with the virus of serum proteins presumed to be complement components. Trypsin digestion of the associated proteins fully restored the HA activity but not infectivity. It was found that the virus underwent minor disruption of the envelope and degradation of M1 protein and genomic RNA.

Relationship between an activated N-ras oncogene and chromosomal abnormality during leukemic progression from myelodysplastic syndrome

The relationship between chromosomal abnormality and oncogene activation was investigated during leukemic progression in two patients with myelodysplastic syndrome (MDS). Both patients had partial or complete deletion of chromosome 5 in metaphase cells obtained throughout the progression to leukemia. Analysis with specific oligonucleotide probes revealed that bone marrow cells containing an activated N-ras oncogene proliferated in a dominant manner during the process of leukemic conversion in both patients. These observations suggest that the chromosomal abnormality may precede activation of the N-ras gene in these patients, and that both the chromosomal abnormality and the activated N-ras oncogene contribute to the development of leukemia.

Constitutive expression of the granulocyte-macrophage colony-stimulating factor gene in human solid tumors

We detected constitutive expression of the granulocyte-macrophage colony-stimulating factor (GM-CSF) gene in 3 human solid tumors by Northern blot analysis. Two of them were also found to secrete the GM-CSF protein by colony forming unit-culture assay. Southern blot analysis of each tumor DNA showed no gross rearrangement of the GM-CSF gene. This is the first report that demonstrates expression of the GM-CSF gene in solid tumors at the mRNA level.

A point mutation at codon 13 of the N-ras oncogene in myelodysplastic syndrome

Patients with a myelodysplastic syndrome (MDS) which has a risk of leukaemic change exhibit a variable clinical course. It has been suggested that the development of leukaemia in patients with MDS may be related to chromosomal abnormalities or genetic alterations: somatic mutation of the N-ras gene is now considered to be a critical step in the genetic basis of human leukaemogenesis. Here we report that DNAs of bone-marrow cells from three out of eight patients with MDS contained an activated N-ras oncogene, as detected by an in vivo selection assay in nude mice with transfected NIH 3T3 cells. Molecular analysis revealed the same single nucleotide substitution at codon 13 in all three transforming N-ras genes. Each of the three patients showed a progression of the disease and a resulting leukaemic change within the following year. Our observation of the mutation at codon 13 in leukaemic cell DNAs from all three cases suggests that activation of the N-ras gene is important in the development of leukaemia in some MDS cases.

Radioimmunoassay of placental alkaline phosphatase in ovarian cancer sera and tissues

A specific radioimmunoassay for human placental alkaline phosphatase has been developed using the 125I-labeled enzyme, highly purified with a fast protein liquid chromatography system and an absorbed rabbit antiserum. The sensitivity of this assay was 0.2 U/L. Serum levels of over 0.2 U/L were found in 27% of ovarian cancer patients, and most of these elevated enzyme levels occurred with more advanced stages of the disease. On the other hand, almost all ovarian cancer tissue contained detectable levels of the enzyme. Serous adenocarcinoma, endometrioid adenocarcinoma, and dysgerminoma had particularly large amounts. Placental alkaline phosphatase was more frequently detected in tissue than in the serum of ovarian cancer, and therefore may be a useful target in immunodetection and immunotherapy and in studying the histopathology of ovarian cancer.

A new radioimmunoassay for human chorionic gonadotropin using monoclonal antibody

A new radioimmunoassay (RIA) for human Chorionic Gonadotropin (hCG) was developed using murine monoclonal antibody to the beta-subunit of hCG (beta-hCG). The IgG fraction of the monoclonal antibody which did not react with 125I-beta-hCG was purified from hybridoma ascites, and covalently coupled to Sepharose 4B. This solid-phase antibody was incubated with standard hCG or serum sampled for 48 hours. The reaction medium was then removed by centrifugation and 125I-beta-hCG and anti-beta-hCG rabbit polyclonal antibody were added to the precipitate. The alcohol precipitation method was used for separating "bound" and "free" forms in the second reaction. The sensitivity for hCG in this assay system was 0.5 mIU/ml serum and the cross-reactivity with human Luteinizing Hormone (hLH) was 0.4%. This assay system was shown to be clinically applicable. Serial serum samples from two patients with trophoblastic disease were assayed and minute amounts of hCG, which could not be determined by conventional assay methods, could be assayed by this new RIA.

Purification of placental alkaline phosphatase and its monoclonal antibody

Monoclonal antibodies (MAbs) to placental alkaline phosphatase (PAlP) were raised by using the hybridoma technique. Spleen cells from immunized mice were fused with the mouse myeloma line NS-1 using 50% polyethylene glycol and cultured in a selection medium. Antibodies were screened by the enzyme immunoassay using immobilized solid-phase antigen and anti-mouse immunogloblin Fab' (rabbit)-beta-D-galactosidase complex. Four double-cloned hybridomas were obtained. The cross-reactivity with different kinds of alkaline phosphatases of the raised MAbs was examined. At first, MAb 11-D-10, with which placenta was stained but liver and small intestine were not stained in indirect immunofluorescence, was selected. Then, the cross-reactivity of MAb 11-D-10 was further investigated by immunoblotting (Western blotting). MAb 11-D-10 reacted with PAlP but did not react with hepatic and intestinal alkaline phosphatase at all. The binding activity of 125I-labeled MAb 11-D-10 with different choriocarcinoma cell lines (SCH, BeWo, NaUCC-1, NaUCC-2, and NaUCC-3) was highest in SCH, then in the order of BeWo, NaUCC-3, NaUCC-1 and NaUCC-2, and correlated to the PAlP content of the cells (SCH greater than BeWo greater than NaUCC-3 greater than NaUCC-1 greater than NaUCC-2). Also the intensity of indirect immunofluorescence of the above cell lines with MAb 11-D-10 correlated with the PAlP content of each cell.