RPMI-1640和DMEM培养基中肝癌细胞系BEL-7402与HepG-2的生长状态比较

背景：DMEM和RPMI-1640是两种最常用的商品化培养基,二者对肝癌细胞生长的影响尚未见直接的对比研究。 目的：比较两种常用培养基对人肝癌BEL-7402与HepG-2细胞系体外生长和增殖效果的影响,从中选择更适合的培养基。 方法：分别应用高糖DMEM与RPMI-1640完全培养液培养BEL-7402和HepG-2细胞,于培养的0,24,48,72,96,  120 h用酸性磷酸酶检测法测定细胞生长和增殖速率,并于倒置显微镜下观察细胞的形态。 结果与结论：结果发现BEL-7402和HepG-2细胞在RPMI-1640培养基中的生长增殖速率均明显高于DMEM培养基 (P < 0.01)。镜下观察证实细胞在RPMI-1640培养基中的黏附和伸展状态更好。因此,建议首选RPMI-1640培养基进行肿瘤细胞体外培养。     

Trisomy 7 mosaicism prenatally misdiagnosed and maternal uniparental disomy in a child with pigmentary mosaicism and Russell- Silver syndrome

Prenatal diagnosis of true mosaic trisomy 7 is rare in amniotic fluid and can be misinterpreted as pseudomosaic. The phenotype is highly variable and may be modified by a maternal uniparental disomy of chromosome 7 leading to mild Russell-Silver syndrome (RSS). We report here the third postnatal case of mosaic trisomy 7 with maternal uniparental disomy of chromosome 7 in a boy presenting a mild RSS. Fetal karyotype performed in amniocentesis for intrauterine growth retardation was considered normal. Mosaic trisomy 7 was diagnosed after birth, on fibroblasts karyotype performed for blaschkolinear pigmentary skin anomalies and failure to thrive. Maternal uniparental disomy of chromosome 7 was observed in blood sample. Retrospectively, trisomic 7 cells were identified in one prenatal long-term flask culture revealing a prenatal diagnosis failure. This report emphasizes the difficulty of assessing fetal mosaicism and distinguishing it from pseudomosaicism in cultured amniocytes. It is important to search for uniparental disomy as an indirect clue of trisomy 7 mosaicism and a major prognosis element. Although there are only few prenatal informative cases, detection of trisomy 7 in amniocentesis appears to be associated with a relatively good outcome when maternal uniparental disomy has been ruled out.     

Hypomelanosis of Ito associated with mosaicism for trisomy 7 and apparent ''pseudomosaicism'' at amniocentesis.

We describe a patient with hypomelanosis of Ito (HI) and typical characteristics. Cytogenetic analysis of fibroblast cultures showed mosaicism for trisomy 7. The trisomy cell line was first observed in an amniotic fluid culture and illustrates the problem of distinguishing pseudomosaicism from true mosaicism.     

Evidence for preferential involvement of chromosome bands 6p21 and 13q14 in amniotic fluid cell balanced translocation pseudomosaicism

Chromosome rearrangement is a relatively common finding in cultured amniotic fluid cells. When cytogenetic abnormalities are confined to one cell or cells from a single culture, they are generally assumed to have arisen in culture (pseudomosaicism). To determine whether or not there might be some specificity in chromosome break-points in balanced translocation multiple cell pseudomosaicism, data has been pooled for 18 cases studied at PDL and 30 cases from the U.S. survey on mosaicism and pseudomosaicism (Hsu & Perlis 1984). Out of a total of 97 break-points, 87 were assigned to Giemsa-staining light bands and 12 to Giemsa-staining dark bands. An excess of break points (29%) were assigned to terminal bands. Two loci appeared to be preferentially involved in rearrangement: six break-points (4 PDL cases and 2 others) were assigned to band 6p21; the region to which the major histocompatibility complex (HLA) has been assigned; Four break-points (all PDL cases) were assigned to 13q14, the region associated with the retinoblastoma locus. This preliminary evidence for specific break-points needs confirmation and long-term follow-up information is needed to determine whether or not there is any clinical significance to these observations.     

"Pseudomosaicism" for 4p- in amniotic fluid cell culture proven to be true mosaicism after birth.

Pseudomosaicism is noted in approximately 1% of amniotic fluid cell studies. Some represent numerical abnormalities, but pseudomosaicism for structural chromosomal abnormalities is also seen. Pseudomosaicism is not usually considered clinically significant. Recently, we evaluated a 13-month-old girl with developmental delay and minor anomalies suggestive of 4p- syndrome. In 5 of 100 peripheral lymphocytes, she had a deletion 46,XX,del(4)(p15). Review of a prenatal amniocentesis study performed on the mother of our patient disclosed that one colony of 18 examined from 2 in situ cultures had the same abnormality, whereas none of the 27 cells from a flask culture showed the abnormality. Results of this study had originally been reported as showing pseudomosaicism. To our knowledge, amniotic fluid pseudomosaicism of a structural abnormality has not previously been shown to reflect true mosaicism in fetal tissue or liveborn children. The actual incidence of this phenomenon is unknown, but it may be present in unexamined children with minimal clinical findings. Apparently only one previous case of mosaic 4p- in a liveborn individual has been reported.     

“Pseudomosaicism” for 4p – in amniotic fluid cell culture proven to be true mosaicism after birth

Pseudomosaicism is noted in approximately 1% of amniotic fluid cell studies. Some represent numerical abnormalities, but pseudomosaicism for structural chromosomal abnormalities is also seen. Pseudomosaicism is not usually considered clinically significant. Recently, we evaluated a 13-month-old girl with developmental delay and minor anomalies suggestive of 4p – syndrome. In 5 of 100 peripheral lymphocytes, she had a deletion 46,XX,del(4)(p15). Review of a prenatal amniocentesis study performed on the mother of our patient disclosed that one colony of 18 examined from 2 in situ cultures had the same abnormality, whereas none of the 27 cells from a flask culture showed the abnormality. Results of this study had originally been reported as showing pseudomosaicism. To our knowledge, amniotic fluid pseudomosaicism of a structural abnormality has not previously been shown to reflect true mosaicism in fetal tissue or liveborn children. The actual incidence of this phenomenon is unknown, but it may be present in unexamined children with minimal clinical findings. Apparently only one previous case of mosaic 4p – in a liveborn individual has been reported.     

不同培养基对人脐静脉内皮细胞体外培养效果的影响

目的研究不同培养基对人脐静脉内皮细胞体外培养生长的影响,探讨内皮细胞的最佳体外扩增培养条件。方法取健康产妇分娩后脐带,用胶原酶Ⅰ消化后得脐静脉内皮细胞,进行原代培养,并用免疫荧光染色的方法对细胞进行鉴定,传代培养时则分别采用RPMI-1640培养基和EGM-2培养基,倒置显微镜观察两种培养条件下细胞的生长状态,同时利用流式细胞仪检测其生长周期,对比培养效果。结果 EGM-2组内皮细胞生长良好,2d后贴壁生长的细胞可达90%。EGM-2组S期细胞比例为（29.07±1.48）%,RPMI-1640培养基组S期细胞为（17.58±3.49）%,二者比较差异有统计学意义（P〈0.01）。结论 EGM-2培养基更适合人脐静脉内皮细胞的体外传代扩增培养。     

Human lymphocyte transformation induced by mitogens and antigens in a serum-free tissue culture system

The use of serum to supplement lymphocyte tissue culture media introduces uncontrolled variables; different serum sources, lots and concentrations can produce variability in experimental results, serum can stimulate or inhibit lymphocytes, and components of serum can react with substances whose effects on lymphocytes are being studied. To avoid these problems, we studied the ability of human peripheral mononuclear cells to survive and to respond to stimulation in an entirely synthetic medium, RPMI-1640 supplemented with L-glutamine, gentamicin, HEPES buffer and magnesium. Optical cell concentration in this serum-free RPMI-1640 was 2.5 × 10⁶ cells/ml, whereas optimal cell concentration in serum containing RPMI-1640 was 1 × 10⁶ cells/ml. In this serum-free RPMI-1640, 50% of the cellular input was recovered as viable cells after 7 days of culture, which was similar to results in serum containing RPMI-1640. Mononuclear cell transformation was induced by phytohemagglutinin, concanavalin A, pokeweed mitogen, streptolysin O and candida. Optimal doses of stimulants and the kinetics of the responses were similar in serum-free and serum containing RPMI-1640. This system can be used to avoid the problems inherent in systems which supplement tissue culture media with serum.     

猪蛔虫幼虫体外培养的初步研究

目的研究适合猪蛔虫幼虫体外培养的最佳条件。方法将猪蛔虫幼虫在不同培养液（KW-2、RPMI-1640、DMEM（含酚红）、DMEM（不含酚红））中进行培养,并观察其存活、生长以及发育情况。结果幼虫在KW-2培养液中生长情况最好,虫体活力很强,3d后成活率最高达87.67%,其次是在RPMI-1640培养液中。在培养液DMEM（含酚红）、DMEM（不含酚红）中生长情况较差,存活不超过7d。其中KW-2培养液中在4～5d出现虫体头端有松动的鞘出现,在RPMI-1640培养液中7～8d出现鞘松动,DMEM（含酚红）、DMEM（不含酚红）中未发现有脱鞘现象出现。结论猪蛔虫的体外培养的最佳条件还需要进一步探索,从而为研究寄生线虫的发育生物学以及特异性发育的功能基因组学奠定基础。     

无/低血清条件下杂交瘤细胞系生长和McAb产生的研究

将3G1/3F8细胞培养于血清浓度为20％、10％、17.5％、5％、2％、1％、0％的RPMI-1640中测定细胞生长曲线和McAb产生曲线。观察血清浓度对细胞生长和McAb产生的影响。用6种无血清培养基对3G1/3F8细胞做适应性培养,活细胞数为对照组的9.5％～55％;McAb产量为81.8％～106.8％。经驯化培养3G1/3F8细胞能够在血清含量1％、5％的培养液生长传代,冻存复苏,活细胞数达到对照组的71.2％～98.2％;McAb产量为104％和108％。对不同血清浓度下接种密度对细胞生长和McAb产量的作用做了实验观察。     

Nutritional folate-deficiency in Chinese hamster ovary cells. Chromosomal abnormalities associated with perturbations in nucleic acid precursors

Folate deficiency is known to induce chromosomal abnormalities. We used a nutritionally folate-deficient Chinese hamster ovary (CHO) cell culture system to examine modulation of chromosome damage by purine or pyrimidine supplementation. The cells were cultured in folate-deficient (Fol-) medium or Fol- medium supplemented with thymidine (dT) or hypoxanthine (Hx) until population growth arrest. The cultures were then switched to complete medium, permitting the cells to begin cell division. Cell-cycle progression was followed by flow cytometry to identify the first mitosis, when samples for analysis were collected. The mitotic index, frequency of chromosomal aberrations in mitotic cells, and relative distribution of different types of aberrations were determined. Cells grown in Fol- medium supplemented with Hx entered the G2/M phase of the cell cycle at 14 hours after media change as compared with 16 hours for Fol- cultures or 24 hours for Fol- cultures supplemented with dT. Cells cultured in Fol- medium alone or supplemented with dT showed similar frequencies of damage, averaging 20-22%, as compared with 2% for control cultures. In contrast, cells grown in Hx-supplemented medium exhibited a lower frequency of damaged mitoses (15%), as well as a reduction in certain types of abnormalities. This latter finding is surprising in light of our previous work showing that the presence of Hx during folate deficiency produced a more severe perturbation of phenotype (cellular enlargement) and growth control (S-phase delay and cell killing) than did dT supplementation or the absence of both nucleotide precursors.     

The centralized prenatal genetics screening program of New York City III: The first 7,000 cases

The Prenatal Diagnosis Laboratory of New York City (PDL) is a regional program for the prevention of genetic diseases. The administrative aspects of the establishment of the laboratory were described in papers I [Hsu, 1981] and II [Hsu and Benn, 1981] in this series. We now report our experience of the first 7,000 referrals to the laboratory. The laboratory achieved a success rate of 99.5% in obtaining a diagnosis. The frequency with which a repeat amniocentesis was required was 1.9%, usually attributable to inadequate initial amniotic fluid volume or condition. Cases were completed in an average time of 20.82 days. A total of 149 (2.13%) cytogenetic abnormalities were detected. There were 59 nonmosaic autosomal trisomies and 29 sex chromosome abnormalities. The incidence of unbalanced structural abnormalities (0.186%) was much higher than that reported in surveys of newborn infants largely because of the prenatal detection of cases with supernumerary chromosomes. The incidence of balanced structural abnormalities was also considerably higher than that found in surveys of the newborn population, in part because of the detection of subtle familial pericentric inversions of common chromosome regions (inv(Y)(p11q11), inv(2) (p11q13), and inv(1)(p11q13)). The incidence of cases with multiple independent chromosome abnormalities was no higher than expected by chance. A high incidence of mosaicism, pseudomosaicism, and maternal cell contamination was found. Screening for neural tube defects accounted for the detection of a further 16 abnormalities. Nearly all women with severely abnormal fetuses (trisomy 13, 18, 21) elected to terminate their pregnancy whereas only 62% of patients with a prenatally diagnosed sex chromosome abnormality elected to terminate their pregnancies. Full details of follow-up and confirmatory studies for unusual diagnoses are reported. Utilization of prenatal diagnosis in the New York City area has increased sharply since PDL became operational. The laboratory's success illustrates the role of a prenatal diagnosis laboratory that provides a service independent of the patient's financial status. The experience further shows the high degree of acceptance of prenatal diagnosis by individuals at high risk for a child with a genetic disorder.     

Improved prenatal detection of fra(X)(q27.3): methods for prevention of false negatives in chorionic villus and amniotic fluid cell cultures

The reliable detection of fra(X)(q27.3) in prenatal samples is important for providing genetic counseling. We have identified 5 new cases of prenatal fragile X [fra(X)] detection in 3 chorionic villus sample (CVS) and 2 amniotic fluid (AF) cell cultures. In 4 of the 5 cases, either excess thymidine (THY) or a combination of THY and 5-fluorodeoxyuridine (FUdR) was clearly superior to FUdR alone as fra(X) inducers. Amniocytes from one case were cultured only in RPMI-1640 and later exposed to FUdR or THY separately. They showed only 2% fra(X) while parallel cultures initiated in Chang medium and incubated in RPMI for at least 7 days (recovery) before fra(X) induction exhibited strikingly increased fra(X) frequencies. Chang medium alone will not allow fra(X) induction in AF (Jenkins EC, Brown WT [1986]: "Genetic Disorders and the Fetus: Diagnosis, Prevention and Treatment." New York: Plenum Press, pp 185-204). Now, using CVS cells, we report that only 1% and 0% fra(X) were detected using FUdR or THY in cells cultured in RPMI for 4 days after removal from Chang medium. Cells with 7 days "recovery" in RPMI exhibited increases from 2 to 6%. Therefore, we have found that Chang medium is very helpful when the appropriate recovery time in another medium is allowed before fra(X) induction. Some false negative reports can be attributed to: induction in Chang medium alone; lack of sufficient recovery time after initiating cells in Chang before induction; and unavailability of the excess THY fra(X) induction system.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cryptic mosaicism for monosomy 20 identified in renal tract cells

We report a post-natal case of mosaic aneuploidy for chromosome 20 in a 4 months old male baby with an abnormal phenotype including dysmorphic features (asymmetric facial growth), ventricular septal defect, hypotonia and bilateral vesicoureteric reflux. Conventional cytogenetics on peripheral blood showed 1 cell of 200 with 47,XY,+20. Further investigations using fluorescent in situ hybridization (FISH) on a urine sample, with a centromere probe for chromosome 20, revealed 39 of 50 cells giving one signal indicative of monosomy 20. FISH analysis of a buccal smear was consistent with disomy 20 as was conventional cytogenetics on skin fibroblasts. This is the fourth reported case of mosaic monosomy 20, the second case where monosomy 20 is present with a trisomy 20 cell and the first case with each aneuploidy found in two separate tissues. The identification of mosaicism is a difficult task since the abnormal cells can be present only in certain tissues and may disappear with selection as the fetus develops, thus leading to single-cell abnormalities that may get dismissed (pseudomosaicism). The use of FISH in this case was crucial in identifying the cryptic mosaic monosomy 20 cell line. The likely mechanism of origin is post-zygotic nondisjunction giving rise to monosomy, disomy and trisomy cell(s) in the same or different tissues. Although no other trisomy 20 cells were found, the abnormal phenotype plus the finding of a monosomy 20 cell line make this mechanism the most plausible explanation. Had we dismissed the single-cell abnormality, the cryptic mosaicism of monosomy 20 would not have been identified. A detailed analysis of all tissues accessible in conjunction with careful consideration of all clinical information available is the best course of action in suspected mosaicism.     

Enhancement of pulmonary metastasis formation and γ-glutamyltranspeptidase activity in B16 melanoma induced by differentiation in vitro

B16 melanoma sublines (B16-F10-BL6 and B16-Fl) exhibited elevated adenosine 3,5-cyclic monophosphate (cAMP) levels when cultured in Dulbecco's modified Eagle's medium (DMEM) in comparison to cells in RPMI-1640 medium. In parallel, cells cultured in DMEM had increased tyrosinase activity, melanization and dendrite formation, all markers of melanoma differentiation. Also, the proliferative rates of both cell lines were decreased by 80–85% when cultured in DMEM relative to cells maintained in RPMI-1640 medium. In these studies, elevated levels of the melanin precursors tyrosine (Tyr) and phenylalanine (Phe) found in DMEM were shown not to be solely responsible for the phenotypic changes observed with DMEM. Both BL6 and B16-Fl cell lines formed more experimental pulmonary tumor metastasis in syngeneic C57BL/6 mice when maintained in DMEM vs RPMI-1640 medium. Analysis of metastasis formation in nude mice with normal and depleted natural killer (NK) cell activity revealed that the enhanced lung colonizing capacity of the BL6 cells maintained in DMEM was independent of the function of T-cell or NK-cell-mediated immunity. A close association between metastatic ability of tested lines and the expression of the membrane-associated enzyme -glutamyltranspeptidase (-GTPase, EC 2.3.2.2) was observed. The highly metastatic BL6 cell line had 20-fold higher levels of -GTPase activity than the weakly metastatic B16-Fl cell line. Both cell lines, when grown in DMEM, had elevated -GTPase activity that paralleled augmentation of metastatic ability. The dramatic changes in lung-colonizing capacity of the variant B16 melanoma cells maintained in DMEM in contrast to those grown in RPMI-1640 medium may serve as a useful model in understanding certain steps involved in triggering cell differentiation as well as metastasis development.     

Production of human interferon-gamma in serum-free medium.

Interferon (IFN)-gamma was produced with a high yield in cultures of human peripheral mononuclear cells by combined stimulation with OK-432 and staphylococcal enterotoxin B. Human mononuclear cells cultured in serum-free medium produced several times as much IFN as those in RPMI-1640 medium containing 10% fetal bovine serum. A synergistic effect of OK-432 and staphylococcal enterotoxin B on the production of IFN-gamma was demonstrated. Ultrogel AcA54 column chromatography of crude IFN showed a single peak with an apparent molecular weight of 43,000. Our production system for human IFN-gamma offers a feasible approach to preparation of large quantities of purified IFN-gamma for structure studies, antibody production, and clinical applications.     

羊水细胞原位培养与产前诊断镶嵌体分析

目的了解载片培养瓶对羊水细胞原位培养的效果,并探讨产前诊断羊水染色体中镶嵌体不同分级水平与临床意义。方法使用载片培养瓶（研究组）与载片培养皿（对照组）对1274例有产前诊断指征的孕妇进行羊水细胞原位培养并G显带分析。结果研究组与对照组培养时间平均为6.7和8.9d,细胞克隆数平均为11.5和6.0个,两组培养天数和细胞克隆数比较差异有统计学意义（χ2=1814.4,P〈0.01;χ2=2049.04,P〈0.01）。羊水镶嵌体检出34例,Ⅰ级水平25例,Ⅱ级水平7例,Ⅲ级水平2例,其中真性镶嵌体3例。结论载片培养瓶对羊水细胞原位培养优于载片培养皿,羊水原位培养镶嵌体分级水平的研究对产前诊断有非常重要的临床意义,Ⅱ级水平不能认为全是假性镶嵌体。     

Analysis of mosaic states in amniotic fluid using the in-situ colony technique

Appropriate counselling and clinical management of the pregnant woman with a mosaic amniotic fluid cell karyotype are difficult. The majority of the data on mosaicism and pseudomosaicism are derived from studies employing the flask technique for the analysis of amniotic fluid cell cultures. Since the majority of laboratories now utilize the in-situ technique, such data may not be relevant when analyzing results from the in-situ colony technique. We reviewed the incidence of mosaicism in 6339 amniotic fluid samples using the in-situ technique. Data are presented on the types of aberrations and clinical outcomes. A classification of mosaicism is presented that distinguishes mosaicism of clinical importance from that which is obviously of extrafetal origin or artifactual. This approach clarifies the significance of mosaic states detected by the in-situ colony technique and provides a rational foundation for genetic counselling and for planning clinical interventions.     

Multiple congenital anomalies in a child born after prenatal diagnosis of trisomy 20mosaicism

The clinical significance of trisomy 20 mosaicism in amniotic fluid cultures has remained unclear so far. We report data on a child with multiple congenital anomalies born after a diagnosis of true trisomy 20 mosaicism in 65% of amniotic fluid cells. The child had generalized dysmorphic features, including facial dysmorphy resembling those of a child with Williams syndrome. The boy also had hypotonia and language delay. Although most of the published cases do not mention any abnormalities in children born after prenatal diagnosis of trisomy 20 mosaicism, the distinct cranio-facial features and the similarities to previous reports of partial or complete chromosome 20 mosaicism raises the possibility that a recognizable pattern of malformation might be associated with the prenatally diagnosable condition in some cases.     

True trisomy 2 mosaicism in amniocytes and newborn liver associated with multiple system abnormalities

Among 58,000 amniocenteses completed, our laboratories found one case of true cytogenetic trisomy 2 mosaicism in a fetus with multiple abnormalities. In contrast, 11 fetuses phenotypically normal at birth were found to have true trisomy 2 mosaicism in their chorionic villus cells among the 10,500 fetuses tested by chorionic villus sampling (CVS). In our single abnormal case, amniocentesis performed at 19 weeks after finding an elevated maternal serum AFP found two independent cultures with trisomy 2 karyotypes in 8 of 25 and 7 of 31 amniocytes, respectively. Although oligohydramnios was noted by ultrasound, the mother elected to continue the pregnancy. At 26 weeks the fetus had intrauterine growth retardation (IUGR), hydronephrosis, and cardiac abnormalities. When delivered by Cesarean section at 30 weeks, the infant had multiple anomalies and developed necrotizing enterocolitis and severe cholestasis. At 5 months coronal magnetic resonance imaging (MRI) displayed delayed myelination and abnormal brain morphology. The patient also exhibited significant growth failure and developmental delay. Although chromosomes were normal in blood, skin fibroblasts, and ascites fluid cells, 4 of 100 hepatic biopsy fibroblasts were 47,XY,+2. Molecular analysis excluded uniparental disomy (UPD) of chromosome 2 in the 46,XY cell line. This and other reports of rare phenotypically abnormal trisomy 2 mosaic fetuses identified by karyotyping amniocytes emphasizes the substantially higher fetal risk of abnormal development than when trisomy 2 is found only in chorionic villus cells. Am. J. Med. Genet. 72:343–346, 1997. © 1997 Wiley-Liss, Inc.