Synthesis and degradation of cyclic ADP-ribose by NAD glycohydrolases

Cyclic adenosine diphosphoribose (cADPR), a recently discovered metabolite of nicotinamide adenine dinucleotide (NAD), is a potent calcium-releasing agent postulated to be a new second messenger. An enzyme that catalyzes the synthesis of cADPR from NAD and the hydrolysis of cADPR to ADP-ribose (ADPR) was purified to homogeneity from canine spleen microsomes. The net conversion of NAD to ADPR categorizes this enzyme as an NAD glycohydrolase. NAD glycohydrolases are ubiquitous membrane-bound enzymes that have been known for many years but whose function has not been identified. The results presented here suggest that these enzymes may function in the regulation of calcium homeostasis by the ability to synthesize and degrade cADPR.

A non-enzymatic p21 protein inhibitor of stress-activated protein kinases

The stress-activated protein kinases (SAPKs), which are identical to the c-Jun amino-terminal kinases (JNKs), are activated in response to a variety of cellular stresses, including DNA damage, heat shock or tumour-necrosis factor-alpha. SAPK, a subfamily of the mitogen-activated protein (MAP) kinases, is a major protein kinase that phosphorylates c-Jun and other transcription factors. SAPK phosphorylation of transcription factors is important in stress-activated signalling cascades. Here we report that the protein p21 WAF1/CIP1/Sd:1, a DNA-damage-inducible cell-cycle inhibitor, acts as an inhibitor of the SAPK group of mammalian MAP kinases. This highlights a new biochemical activity of p21, which may provide the first evidence for a non-enzymatic inhibitory protein for SAPK. We suggest that p21, by inhibiting SAPK, may participate in regulating signalling cascades that are activated by cellular stresses such as DNA damage.

Beginning regular exercise in early pregnancy: effect on fetoplacental growth

OBJECTIVE

Our purpose was to test the null hypothesis that beginning regular, moderate-intensity exercise in early pregnancy has no effect on fetoplacental growth.

STUDY DESIGN

Forty-six women who did not exercise regularly were randomly assigned at 8 weeks either to no exercise (n = 24) or to weight-bearing exercise (n = 22) 3 to 5 times a week for the remainder of pregnancy. Outcome variables included antenatal placental growth rate and neonatal and placental morphometric measurements.

RESULTS

The offspring of the exercising women were significantly heavier (corrected birth weight: 3.75 +/- 0.08 kg vs 3.49 +/- 0.07 kg) and longer (51.8 +/- 0.3 cm vs 50.6 +/- 0.3 cm) than those born to control women. The difference in birth weight was the result of an increase in both lean body mass and fat mass. In addition, midtrimester placental growth rate was faster (26 +/- 2 cm(3)/wk vs 21 +/- 1 cm(3)/wk) and morphometric indexes of placental function were greater in the exercise group. There were no significant differences in neonatal percentage body fat, head circumference, ponderal index, or maternal weight gain.

CONCLUSIONS

These data indicate that beginning a moderate regimen of weight-bearing exercise in early pregnancy enhances fetoplacental growth.

Longitudinal and cross-sectional analysis of atrophy in pharmacoresistant temporal lobe epilepsy

BACKGROUND

Whether recurrent epileptic seizures induce brain damage is debated. Disease progression in epilepsy has been evaluated only in a few community-based studies involving patients with seizures well controlled by medication. These studies concluded that epilepsy does not inevitably lead to global cerebral damage.

OBJECTIVE

To track the progression of neocortical atrophy in pharmacoresistant temporal lobe epilepsy (TLE) using longitudinal and cross-sectional designs.

METHODS

Using a fully automated measure of cortical thickness on MRI, we studied a homogeneous sample of patients with pharmacoresistant TLE. In the longitudinal analysis (n = 18), fixed-effect models were used to quantify cortical atrophy over a mean interscan interval of 2.5 years (range = 7 to 90 months). In the cross-sectional analysis (n = 121), we correlated epilepsy duration and thickness. To dissociate normal aging from pathologic progression, we compared aging effects in TLE to healthy controls.

RESULTS

The longitudinal analysis mapped progression in ipsilateral temporopolar and central and contralateral orbitofrontal, insular, and angular regions. In patients with more than 14 years of disease, atrophy progressed more rapidly in frontocentral and parietal regions that in those with shorter duration. The cross-sectional study showed progressive atrophy in the mesial and superolateral frontal, and parietal cortices.

CONCLUSIONS

Our combined cross-sectional and longitudinal analysis in patients with pharmacoresistant temporal lobe epilepsy demonstrated progressive neocortical atrophy over a mean interval of 2.5 years that is distinct from normal aging, likely representing seizure-induced damage. The cumulative character of atrophy underlies the importance of early surgical treatment in this group of patients.

Surveillance for recurrent head and neck cancer using positron emission tomography

PURPOSE

Earlier detection of head and neck cancer recurrence may improve survival. We evaluated the ability of [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) to detect recurrence in a prospective trial using sequential PET scans.

PATIENTS AND METHODS

Serial posttherapy FDG-PET was prospectively performed in 44 patients with stage III or IV head and neck cancer. PET was performed twice during the first posttreatment year (at 2 and 10 months after therapy) and thereafter as needed. After therapy, patients were grouped, based on tissue biopsies, into those who achieved a complete response (CR) and those who had residual disease (RD). Patients who achieved a CR were further grouped into those without evidence of disease and those who had recurrence by 1 year after completion of therapy. Disease status as determined by physical examination (PE), PET, and correlative imaging was compared.

RESULTS

Eight patients were lost to follow-up and six had RD after therapy. Of the remaining 30 patients with a CR, 16 had recurrence in the first year after therapy. Five of these 16 patients had recurrence detected by PET only, four by PET and correlative imaging only, five by PE and PET only, and two by PE, correlative imaging, and PET. Only PET detected all recurrences in the first year. PET performed better than correlative imaging (P =.013) or PE (P =.002) in the detection of recurrence.

CONCLUSION

PET can detect head and neck tumor recurrence when it may be undetectable by other clinical methods. FDG-PET permits highly accurate detection of head and neck cancer recurrence in the posttherapy period.

Distribution of obstructive intimal lesions and their cellular phenotypes in chronic pulmonary hypertension. A morphometric and immunohistochemical study

We investigated the distribution of pulmonary arteriopathy in chronic pulmonary hypertension (PH) in a quantitative histopathologic study, using computer-assisted image analysis. We also examined the histologic manifestations and cellular phenotypes of various obstructive intimal lesions in PH with an immunohistochemical method. A total of 53 lungs removed at autopsy or explantation were obtained for the study from 51 documented cases of moderate to severe PH (15 cases of primary pulmonary hypertension [PPH], eight cases of Eisenmenger's syndrome [EISEN], 22 cases of chronic major-vessel thromboembolic disease [CTED], and three cases of PH associated with other known causes), and two unused donor lungs served as normal controls. Intimal thickening in PPH was most prominent in small pulmonary arteries and arterioles less than 200 micrometer in diameter. Plexiform lesions in PPH were associated with significantly smaller arteries than in EISEN. Arteries larger than 400 micrometer showed a significant intimal thickening only in CTED. Obstructive intimal lesions in PH comprised a morphologic spectrum with frequent intermediate forms between plexiform and thrombotic lesions. Most cells within various intimal lesions showed an immunoprofile of myofibroblasts that were positive for vimentin and alpha-smooth muscle actin, but negative for desmin and endothelial markers including Factor VIII, clonal designator (CD)31, and CD34. Endothelial markers were positive only in the single layer of cells lining slitlike lumens, when the latter were present. In conclusion, major types of PH had characteristic distribution patterns of obstructive intimal lesions, showing mainly a myofibroblastic phenotype and variable endothelial/vascular differentiation.

Mantle-zone lymphoma: a follicular variant of intermediate lymphocytic lymphoma

A clinicopathologic analysis of 12 cases of a morphologically distinctive non-Hodgkin's malignant lymphoma which appeared to arise from the mantle zones of secondary lymphoid follicles is presented. In lymph node and spleen sections, atypical small lymphoid cells with slightly irregular and indented nuclear contours proliferated as wide mantles around non-neoplastic-appearing germinal centers. Surface marker analysis performed on lymph nodes revealed a monoclonal B-cell proliferation in two cases. Clinically, the patients usually had advanced disease (Stage III or IV) associated with splenomegaly. This lymphoma appears to be relatively low-grade, since nine of 12 patients are alive with a median follow-up period of 28.5 months. We believe that thie "mantle-zone lymphoma" represents a nodular or follicular variant of intermediate lymphocytic lymphoma.

Immunohistochemistry for hMLH1 and hMSH2: a practical test for DNA mismatch repair-deficient tumors

Inactivation of deoxyribonucleic acid (DNA) mismatch repair genes, most commonly human mutL homologue 1 (hMLH1) or human mutS homologue 2 (hMSH2), is a recently described alternate pathway in cancer development and progression. The resulting genetic instability is characterized by widespread somatic mutations in tumor DNA, and is termed high-frequency microsatellite instability (MSI-H). Although described in a variety of tumors, mismatch repair deficiency has been studied predominantly in colorectal carcinoma. Most MSI-H colorectal carcinomas are sporadic, but some occur in patients with hereditary nonpolyposis colorectal cancer (HNPCC), and are associated with germline mutations in mismatch repair genes. Until now, the identification of MSI-H cancers has required molecular testing. To evaluate the role of immunohistochemistry as a new screening tool for mismatch repair-deficient neoplasms, the authors studied the expression of hMLH1 and hMSH2, using commercially available monoclonal antibodies, in 72 formalin-fixed, paraffin-embedded tumors that had been tested previously for microsatellite instability. They compared immunohistochemical patterns of 38 MSI-H neoplasms, including 16 cases from HNPCC patients with known germline mutations in hMLH1 or hMSH2, with 34 neoplasms that did not show microsatellite instability. Thirty-seven of 38 MSI-H neoplasms were predicted to have a mismatch repair gene defect, as demonstrated by the absence of hMLH1 and/or hMSH2 expression. This included correspondence with all 16 cases with germline mutations. All 34 microsatellite-stable cancers had intact staining with both antibodies. These findings clearly demonstrate that immunohistochemistry can discriminate accurately between MSI-H and microsatellite-stable tumors, providing a practical new technique with important clinical and research applications.

Integration of genetic, clinical, and INR data to refine warfarin dosing

Well-characterized genes that affect warfarin metabolism (cytochrome P450 (CYP) 2C9) and sensitivity (vitamin K epoxide reductase complex 1 (VKORC1)) explain one-third of the variability in therapeutic dose before the international normalized ratio (INR) is measured. To determine genotypic relevance after INR becomes available, we derived clinical and pharmacogenetic refinement algorithms on the basis of INR values (on day 4 or 5 of therapy), clinical factors, and genotype. After adjusting for INR, CYP2C9 and VKORC1 genotypes remained significant predictors (P < 0.001) of warfarin dose. The clinical algorithm had an R(2) of 48% (median absolute error (MAE): 7.0 mg/week) and the pharmacogenetic algorithm had an R(2) of 63% (MAE: 5.5 mg/week) in the derivation set (N = 969). In independent validation sets, the R(2) was 26-43% with the clinical algorithm and 42-58% when genotype was added (P = 0.002). After several days of therapy, a pharmacogenetic algorithm estimates the therapeutic warfarin dose more accurately than one using clinical factors and INR response alone.

Bandgap modulation of carbon nanotubes by encapsulated metallofullerenes

Motivated by the technical and economic difficulties in further miniaturizing silicon-based transistors with the present fabrication technologies, there is a strong effort to develop alternative electronic devices, based, for example, on single molecules. Recently, carbon nanotubes have been successfully used for nanometre-sized devices such as diodes, transistors, and random access memory cells. Such nanotube devices are usually very long compared to silicon-based transistors. Here we report a method for dividing a semiconductor nanotube into multiple quantum dots with lengths of about 10nm by inserting Gd@C82 endohedral fullerenes. The spatial modulation of the nanotube electronic bandgap is observed with a low-temperature scanning tunnelling microscope. We find that a bandgap of approximately 0.5eV is narrowed down to approximately 0.1eV at sites where endohedral metallofullerenes are inserted. This change in bandgap can be explained by local elastic strain and charge transfer at metallofullerene sites. This technique for fabricating an array of quantum dots could be used for nano-electronics and nano-optoelectronics.

Heterogeneity of microtubule-associated protein 2 during rat brain development

The electrophoretic pattern of the large microtubule-associated protein, MAP2, changes during rat brain development. Immunoblots of NaDodSO4 extracts obtained from the cerebral cortex, cerebellum, and thalamus at 10-15 days after birth reveal only a single electrophoretic species when probed with any of three MAP2 monoclonal antibodies. By contrast, adult MAP2 contains two immunoreactive species, MAP2a and MAP2b. The single band of MAP2 from immature brain electrophoretically comigrates with adult MAP2b. Between postnatal days 17 and 18, immature MAP2 simultaneously resolves into two species in both the cerebellum and cerebral cortex. Immunoblots of NaDodSO4 extracts from spinal cord demonstrate the adult complement of MAP2 by day 10, indicating that MAP2 does not change coordinately throughout the entire central nervous system. In vitro cAMP-dependent phosphorylation of immature MAP2 causes a band split reminiscent of that seen during brain development in vivo. The possibility that the developmentally regulated changes observed in MAP2 during brain maturation are due to timed phosphorylation events is discussed.

Role of peroxiredoxins in regulating intracellular hydrogen peroxide and hydrogen peroxide-induced apoptosis in thyroid cells

Peroxiredoxins (Prxs) play an important role in regulating cellular differentiation and proliferation in several types of mammalian cells. One mechanism for this action involves modulation of hydrogen peroxide (H(2)O(2))-mediated cellular responses. This report examines the expression of Prx I and Prx II in thyroid cells and their roles in eliminating H(2)O(2) produced in response to thyrotropin (TSH). Prx I and Prx II are constitutively expressed in FRTL-5 thyroid cells. Prx I expression, but not Prx II expression, is stimulated by exposure to TSH and H(2)O(2). In addition, methimazole induces a high level of Prx I mRNA and protein in these cells. Overexpression of Prx I and Prx II enhances the elimination of H(2)O(2) produced by TSH in FRTL-5 cells. Treatment with 500 micrometer H(2)O(2) causes apoptosis in FRTL-5 cells as evidenced by standard assays of apoptosis (i.e. terminal deoxynucleotidyl transferase deoxyuridine triphosphate-biotin nick end labeling, BAX expression, and poly(ADP-ribose) polymerase cleavage. Overexpression of Prx I and Prx II reduces the amount of H(2)O(2)-induced apoptosis measured by these assays. These results suggest that Prx I and Prx II are involved in the removal of H(2)O(2) in thyroid cells and can protect these cells from undergoing apoptosis. These proteins are likely to be involved in the normal physiological response to TSH-induced production of H(2)O(2) in thyroid cells.

Kaempferol acts through mitogen-activated protein kinases and protein kinase B/AKT to elicit protection in a model of neuroinflammation in BV2 microglial cells

BACKGROUND AND PURPOSE

Kaempferol, a dietary flavonoid and phyto-oestrogen, is known to have anti-inflammatory properties. Microglial activation has been implicated in various neurodegenerative diseases. Anti-inflammatory effects of kaempferol and the underlying mechanisms were investigated by using LPS-stimulated microglial BV2 cells.

EXPERIMENTAL APPROACH

Cell viability was measured using MTT and neutral red assays. elisa, Western blot, immunocytochemistry and electrophoretic mobility-shift assay were used to analyse NO, PGE(2) , TNF-α and IL-1β production, inducible NOS (iNOS), COX-2 expression and the involvement of signalling pathways such as toll-like receptor-4 (TLR4), MAPK cascades, PKB (AKT) and NF-κB. Accumulation of reaction oxygen species (ROS) was measured by nitroblue tetrazolium and 2'7'-dichlorofluorescein diacetate assay. Matrix metalloproteinase activity was investigated by zymography and immunoblot assay. Phagocytotic activity was assessed by use of latex beads.

KEY RESULTS

Kaempferol significantly attenuated LPS-induced NO, PGE(2) , TNF-α, IL-1β and ROS production and phagocytosis in a concentration-dependent manner. Kaempferol suppressed the expression of iNOS, COX-2, MMP-3 and blocked the TLR4 activation. Moreover, kaempferol inhibited LPS-induced NF-κB activation and p38 MAPK, JNK and AKT phosphorylation.

CONCLUSION AND IMPLICATIONS

Kaempferol was able to reduce LPS-induced inflammatory mediators through the down-regulation of TLR4, NF-κB, p38 MAPK, JNK and AKT suggesting that kaempferol has therapeutic potential for the treatment of neuroinflammatory diseases.

X-gene product of hepatitis B virus induces apoptosis in liver cells

Hepatitis B virus is a causative agent of hepatocellular carcinoma, and in the course of tumorigenesis, the X-gene product (HBx) is known to play important roles. Here, we investigated the transforming potential of HBx by conventional focus formation assay in NIH3T3 cells. Cells were cotransfected with the HBx expression plasmid along with other oncogenes including Ha-ras, v-src, v-myc, v-fos, and E1a. Unexpectedly, the introduction of HBx completely abrogated the focus-forming ability of all five tested oncogenes. In addition, the cotransfection of Bcl-2, an apoptosis inhibitor, reversed the HBx-mediated inhibition of focus formation, suggesting that the observed repression of focus formation by HBx is through the induction of apoptosis. Next, to test unequivocally whether HBx induces apoptosis in liver cells, we established stable Chang liver cell lines expressing HBx under the control of a tetracycline-inducible promoter. Induction of HBx in these cells in the presence of 1% calf serum resulted in typical apoptosis phenomena such as DNA fragmentation, nuclear condensation, and fragmentation. Based on these results, we propose that HBx sensitizes liver cells to apoptosis upon hepatitis B virus infection, contributing to the development of hepatitis and the subsequent generation of hepatocellular carcinoma.

Molecular cloning, expression, and characterization of angiopoietin-related protein. angiopoietin-related protein induces endothelial cell sprouting

Using degenerate polymerase chain reaction, we isolated a cDNA encoding a novel 493-amino acid protein from human and mouse adult heart cDNAs and have designated it angiopoietin-related protein-2 (ARP2). The NH(2)-terminal and COOH-terminal portions of ARP2 contain the characteristic coiled-coil domain and fibrinogen-like domain that are conserved in angiopoietins. ARP2 has two consensus glycosylation sites and a highly hydrophobic region at the NH(2) terminus that is typical of a secretory signal sequence. Recombinant ARP2 expressed in COS cells is secreted and glycosylated. In human adult tissues, ARP2 mRNA is most abundant in heart, small intestine, spleen, and stomach. In rat embryos, ARP2 mRNA is most abundant in the blood vessels and skeletal muscles. Endothelial and vascular smooth muscle cells also contain ARP2 mRNA. Recombinant ARP2 protein induces sprouting in vascular endothelial cells but does not bind to the Tie1 or Tie2 receptor. These results suggest that ARP2 may exert a function on endothelial cells through autocrine or paracrine action.

The plasma levels of interleukin-12 in schizophrenia, major depression, and bipolar mania: effects of psychotropic drugs

Interleukin-12 (IL-12) plays a key role in promoting T helper 1 (Th1) responses and subsequent cell-mediated immunity. Given the role of cytokines in the pathogenesis of psychiatric disorders, the dysregulation of IL-12 in these illnesses would be expected. We measured the plasma levels of IL-12 in 102 psychiatric patients (43 schizophrenia, 34 major depression and 25 bipolar disorder) and 85 normal controls. In addition, IL-12 levels of the patients were measured after an 8-week treatment to assess whether the levels were affected by medication. The IL-12 levels of the patient group with major depression were significantly higher than that of the control group, whereas no differences were found among the other groups. IL-12 values of the three patient groups decreased significantly after 8 weeks of treatment. These findings support the hypothesis that activation of the inflammatory response system and in particular of Th-1-like cells, is involved in the pathophysiology of major depression and that repeated administration of antidepressive and antipsychotic drugs may suppress IL-12 plasma concentrations in psychiatric patients.

Srg3, a mouse homolog of yeast SWI3, is essential for early embryogenesis and involved in brain development

Srg3 (SWI3-related gene product) is a mouse homolog of yeast SWI3, Drosophila melanogaster MOIRA (also named MOR/BAP155), and human BAF155 and is known as a core subunit of SWI/SNF complex. This complex is involved in the chromatin remodeling required for the regulation of transcriptional processes associated with development, cellular differentiation, and proliferation. We generated mice with a null mutation in the Srg3 locus to examine its function in vivo. Homozygous mutants develop in the early implantation stage but undergo rapid degeneration thereafter. An in vitro outgrowth study revealed that mutant blastocysts hatch, adhere, and form a layer of trophoblast giant cells, but the inner cell mass degenerates after prolonged culture. Interestingly, about 20% of heterozygous mutant embryos display defects in brain development with abnormal organization of the brain, a condition known as exencephaly. Histological examination suggests that exencephaly is caused by the failure in neural fold elevation, resulting in severe brain malformation. Our findings demonstrate that Srg3 is essential for early embryogenesis and plays an important role in the brain development of mice.

Genetic predictors for acute experimental cold and heat pain sensitivity in humans

BACKGROUND

The genetic contribution to pain sensitivity underlies a complex composite of parallel pain pathways, multiple mechanisms, and diverse inter-individual pain experiences and expectations.

METHODS

Variations for genes encoding receptors related to cold and heat sensation, such as transient receptor potential A subtype 1 (TRPA1), M subtype 8 (TRPM8), V subtype 1 (TRPV1), delta opioid receptor subtype 1 (OPRD1), catechol O-methyltransferase (COMT), and fatty acid amide hydrolyase (FAAH), were investigated in four major ethnic populations.

RESULTS

We defined 13 haplotype blocks in European Americans, seven blocks in African Americans, seven blocks in Hispanic subjects, and 11 blocks in Asian Americans. Further study in European American subjects found significant associations between short duration cold pain sensitivity and variations in TRPA1, COMT, and FAAH in a gender dependent manner. Our observations demonstrate that genetic variations in TRPA1, COMT, and FAAH contribute gender specifically to individual variations in short duration cold pain sensitivity in a European American cohort.

CONCLUSIONS

The effects of TRPA1 variations on experimental short duration heat pain sensitivity may contribute to inter-individual variation in pain sensitivity in humans.

Normative data on the Korean version of the Boston Naming Test

The purpose of this study is to introduce the Korean version of the Boston Naming Test (K-BNT) and to present the normative data. The K-BNT contains the same number of test items and uses the identical general administration method as the original Boston Naming Test (BNT). However, most of the items had to be altered due to the linguistic and cultural differences between Korean and English speakers. We administered 60 line-drawing pictures to six hundred normal participants in eight age groups (15-19, 20-24, 25-34, 35-44, 45-54, 55-64, 65-74, and 75 years and older), five educational levels (0, 1-6, 7-9, 10-12, and 13 years and more), and gender. Since the K-BNT scores were not affected by gender and found not to be significantly different among some age groups, we finalized each cell based on four age groups (15-44, 45-54, 55-74, and 75 years and older) and five education levels (0, 1-6, 7-9, 10-12, and 13 years and more). The highest score was achieved by the 15-44 age group with 13 and more years of education (M = 53.93, SD = 3.06), and the lowest by those of 75 years and older with no education (M = 27.42, SD = 8.22).

Human amniotic fluid-derived stem cells have characteristics of multipotent stem cells

OBJECTIVES

To characterize mesenchymal stem cell-like cells isolated from human amniotic fluid for a new source of therapeutic cells.

MATERIALS

Fibroblastoid-type cells obtained from amniotic fluid at the time of birth.

METHODS

The ability of ex vivo expansion was investigated until senescence, and stem cell-like characteristics were analyzed by examining differentiation potential, messenger RNA expression and immunophenotypes.

RESULTS AND CONCLUSIONS

A morphologically homogenous population of fibroblastoid-type (HAFFTs) cells, similar to mesenchymal stem cells from bone marrow (BM-MSCs), was obtained at the third passage. The cells became senescent after 27 passages over a period of 8 months while undergoing 66 population doublings. Under appropriate culture conditions, by the 8th passage they differentiated into adipocytes, osteocytes, chondrocytes and neuronal cells, as revealed by oil red O, von Kossa, Alcian blue and anti-NeuN antibody staining, respectively. Immunophenotype analyses at the 17th passage demonstrated the presence of TRA-1-60; SSEA-3 and-4; collagen types I, II, III, IV and XII; fibronectin; alpha-SMA; vimentin; desmin; CK18; CD44; CD54; CD106; FSP; vWF; CD31; and HLA ABC. Reverse transcriptase-polymerase chain reaction analysis of the HAFFTs from passages 6-20 showed consistent expression of Rex-1, SCF, GATA-4, vimentin, CK18, FGF-5 and HLA ABC genes. Oct-4 gene expression was observed up to the 19th passage but not at the 20th passage. HAFFTs showed telomerase activity at the 5th passage with a decreased level by the 21st passage. Interestingly, BMP-4, AFP, nestin and HNF-4alpha genes showed differential gene expression during ex vivo expansion. Taken together, these observations suggest that HAFFTs are pluripotent stem cells that are less differentiated than BM-MSCs, and that their gene expression profiles vary with passage number during ex vivo expansion.