Genetic transfer of a functional human interferon alpha receptor into mouse cells: cloning and expression of its cDNA

A cDNA coding for the human interferon alpha receptor has been cloned using a gene transfer approach. This consists of transferring human DNA to mouse cells and selecting for cells sensitive to human interferon alpha. The transfected cells expressed the human interferon alpha receptor, and a 5 kb human DNA was isolated from a secondary transfectant. This DNA defects an mRNA present in human cells and was used to clone a 2.7 kb cDNA from a library constructed from human Daudi cells. The sequence of the cDNA is presented. It codes for a glycoprotein of 557 amino acids with an N-terminal hydrophobic region and a single transmembrane-spanning segment. Mouse cells expressing the cDNA become sensitive to the antiviral activity of and express binding sites for human interferon alpha, demonstrating that the cloned cDNA encodes a functional human interferon alpha receptor.     

Production of antigen-specific human monoclonal antibodies: comparison of mice carrying IgH/kappa or IgH/kappa/lambda transloci

Here we compare human monoclonal antibody (MAb) production from mouse strains that carry disruptions of their endogenous mouse IgH/IgK loci and harbor human IgM + Igkappa(BABkappa) or human IgM + Igkappa + IgA transloci (BABkappa,lambda). We found that whereas both strains proved effective for the isolation of antigen-specific IgM antibodies, many of the IgM MAbs elicited from BABkappa comprise human mu chains that are associated with mouse lambda chains. In contrast, BABkappa,lambda mice gave rise to fully functional, polymeric human IgM antibodies comprising both human IgH and human IgL chains. Therefore, the inclusion of a human Iglambda translocus (in addition to the human IgH + Igkappa transloci) not only diminishes problems of endogenous mouse Iglambda expression but also provides a strain of mice that yields fully human MAbs to a wide range of antigens, as witnessed by the isolation of MAbs to human blood cells, tumor cell lines, and an immunoglobulin idiotype.     

Genetic characterization of human c-rel sequences.

We isolated and sequenced a human genomic-DNA segment that is homologous to a portion of v-rel, the transforming gene of reticuloendotheliosis virus (strain T). We also localized the human rel sequences to human chromosome 2 by screening a panel of rodent X human somatic-cell hybrids with the newly described human rel segment.     

Recellularization of decellularized human adipose-tissue-derived extracellular matrix sheets with other human cell types

Decellularized human extracellular matrices (ECMs) are an extremely appealing biomaterial for tissue engineering and regenerative medicine. In this study, we decellularized human adipose tissue, fabricated a thin ECM sheet and explored the potential of this human adipose-derived ECM sheet as a substrate to support the formation of tissues other than adipose tissue. Acellular ECM sheets were fabricated from human adipose tissue through successive physical and chemical treatments: homogenization, centrifugation, casting, freeze-drying and sodium dodecyl sulfate treatment. The ECM sheets exhibited good mechanical properties, despite their porous structure. They degraded quickly in the presence of collagenase and the degradation rate increased with the collagenase concentration in phosphate-buffered saline. Five different human cell types, covering a broad range of cells and applications (normal human dermal fibroblasts, human aortic smooth muscle cells, human chondrocytes, human umbilical vein endothelial cells and human adipose-derived stem cells), were seeded onto the ECM sheets. All the human cell types spread well, proliferated and were successfully integrated into the decellularized ECM sheet. Overall, the results suggest that recellularized ECM sheets are a promising substitute for defective or damaged human tissues.     

人体肠道病毒组学研究进展

人体微生物组计划开展近10年来,大量的研究显示人体微生物通过各种方式深刻地影响着人体健康。人体肠道内丰富多样的病毒构成了肠道病毒组,是人体微生物组的重要组成部分,和人体健康密切相关。本文综述了近些年国际上人体肠道病毒组研究的最新进展,分别从人体肠道病毒组的组成特征、肠道病毒组-细菌组-人体间的相互作用及其对人体健康的影响、病毒组研究的技术策略及挑战等方面进行了论述,探讨了肠道病毒组在人体疾病预防和治疗领域应用的可行性。     

Signaling of human ciliary neurotrophic factor (CNTF) revisited. The interleukin-6 receptor can serve as an alpha-receptor for CTNF

Human ciliary neurotrophic factor (CNTF) is a neurotrophic cytokine that exerts a neuroprotective effect in multiple sclerosis and amyotrophic lateral sclerosis. Clinical application of human CNTF, however, was prevented by high toxicity at higher dosages. Human CNTF elicits cellular responses by induction of a receptor complex consisting of the CNTF alpha-receptor (CNTFR), which is not involved in signal transduction, and the beta-receptors gp130 and leukemia inhibitory factor receptor (LIFR). Previous studies with rat CNTF demonstrated that rat CNTF is unable to interact with the human interleukin-6 alpha-receptor, whereas at high concentrations, it can directly induce a signaling heterodimer of human gp130 and human LIFR in the absence of the CNTF receptor. Here, we demonstrate that human CNTF cannot directly induce a heterodimer of human gp130 and LIFR. However, human CNTF can use both the membrane-bound and the soluble human IL-6R as a substitute for its cognate alpha-receptor and thus widen the target spectrum of human CNTF. Engineering a CNTFR-specific human CNTF variant may therefore be a prerequisite to improving the safety profile of CNTF.     

Differential expression of the human Thy-1 gene in rodent-human somatic cell hybrids [corrected

Thy-1 is a cell surface differentiation marker which shows distinct patterns of tissue-specific expression in different species. In man, the Thy-1 antigen is encoded by chromosome 11. We have examined the regulatory signals determining human Thy-1 expression through serologic analysis of rodent-human somatic cell hybrids retaining human chromosome 11 in which the fusion partners belong to distinct differentiation lineages. Cell surface expression of human Thy-1 was determined by mixed hemadsorption assays with two monoclonal antibodies (mAb), K117 and L127, shown to detect authentic human Thy-1 through analysis of COS-7 monkey kidney cells transfected with a cloned human Thy-1 gene. Three different patterns of human Thy-1 expression were observed when hybrid cells, constructed with different human and rodent cell types, were tested with mAb K117 and L127. Hybrids formed between Thy-1+ human neuroblastoma cells and Thy-1- mouse neuroblastoma cells, or hybrids between Thy-1+ human fibroblasts and the Thy-1- mouse kidney carcinoma, RAG, retain human Thy-1 expression. In contrast, hybrids formed between either Thy-1+ human neuroblastoma cells or Thy-1+ human fibroblasts and Thy-1- mouse L cells lose expression of human Thy-1 even though chromosome 11 is retained. Finally, hybrids formed between Thy-1- human peripheral lymphocytes or a Thy-1- lymphoblastoid B cell line and Thy-1- Chinese hamster fibroblasts begin to express human Thy-1. These studies suggest that both positive and negative trans-acting signals may play a role in the tissue-specific regulation of the human Thy-1 gene.     

Construction and functional analysis of hybrid interleukin-6 variants. Characterization of the role of the C-terminus for species specificity.

We have constructed several hybrid human interleukin-6 (IL-6) variants in which the carboxyl-terminus, which includes a receptor binding site of IL-6 has been replaced with the C-terminus of various proteins homologous to human IL-6. IL-6 hybrids with the C-terminus of human growth hormone and human granulocyte-colony stimulating factor maintain part of the biological activity of human IL-6. Replacing the C-terminus of human IL-6 with the C-terminus of mouse and rat IL-6 resulted in a normal or increased activity on a mouse cell line; however, this gave a low (to 200-fold less) activity on a human cell line compared to wild-type human IL-6. We therefore conclude that the C-terminus of IL-6 plays an important role in the species specificity of IL-6.     

ASHG activities relative to education: Human genetics as a component of medical school curricula: A report to the American society of human genetics

In recent years, there has been a remarkable increase in both the rate of acquiring new information about human genetics and the importance of human genetics for modern health care. As a result, human genetics educators have queried whether the teaching of human genetics in North-American medical schools has kept pace with these increases. To address this question, a survey of these medical schools was undertaken to assess how human geneticists perceive the teaching of human genetics in their respective institutions. The results of the survey, begun and completed in 1985, indicate the following: (1) the teaching of human genetics in medical schools is extremely variable from one institution to another, with some schools having no identifiable human genetics teaching at all; (2) the relevance of human genetics to other basic science and clinical disciplines apparently leads to noncategorical or fragmented teaching of human genetics, which may also contribute to the absence of a specific medical school course in the subject; and (3) there is a need for closer collaboration between human genetics educators and their respective medical school administrators and curriculum committees.     

Activation and repression of myogenesis in somatic cell hybrids: evidence for trans-negative regulation of MyoD in primary fibroblasts

We show that transfer of human fibroblast chromosome 11 (containing the human MyoD gene) from primary cells into 10T1/2 mouse fibroblasts by microcell fusion activates expression of the transferred human MyoD gene and converts these cells to myoblasts. Transfer of human chromosome 11 into B78 melanoma cells also leads to the activation of human MyoD. In contrast to the results where a single chromosome 11 is transferred, whole-cell hybrids between 10T1/2 cells and human skin fibroblasts do not express the myogenic phenotype; however, when specific human chromosomes are lost, myogenesis occurs. These results suggest that the MyoD locus is potentially functional in primary human fibroblasts, but is normally repressed in trans by a locus on a different human fibroblast chromosome.     

Cellular retinaldehyde-binding protein-like (CRALBPL), a novel human Sec14p-like gene that is upregulated in human hepatocellular carcinomas, may be used as a marker for human hepatocellular carcinomas

Sec14p-like lipid-binding domain (SEC14 domain) is an evolutionarily conserved protein domain often found in secretory proteins, such as Saccharomyces cerevisiae phosphatidylinositol transfer protein Sec14p, and in lipid-regulated proteins, such as GTPase-activating proteins, guanine nucleotide exchange factors, and neurofibromin. We have cloned a novel human gene, cellular retinaldehyde-binding protein-like (CRALBPL), containing SEC14 domain from the cDNA library of human fetal brain. The RT-PCR expression pattern of 16 adult human tissues indicated that CRALBPL was only expressed in brain, while it was expressed in all of seven human carcinoma cell lines we used, especially in human gastric adenocarcinoma cell line, human rhabdomyoma cell line, human hepatocellular carcinoma (HCC) cell line, and human prostatic carcinoma cell line. Further, we found that CRALBPL has a remarkably more abundant RT-PCR expression pattern in human HCC cell lines than in normal human liver cell line, and the same result was gained when RT-PCR expression patterns between human HCC specimens and normal human liver specimens were compared. We also found that CRALBPL is located mainly in cytoplasm in human liver cell line L-02, which is consistent with the common function of Sec14p-like domain family. Our results show that CRALBPL may be used as a marker for human HCCs.     

Assignment of the gene for acid beta-glucosidase to human chromosome 1.

The structural gene for human acid beta-glucosidase (GBA) has been assigned to chromosome 1 using somatic cell hybridization techniques for gene mapping. The human enzyme was detected in mouse RAG cell-human fibroblast cell hybrids by a sensitive double antibody immunoprecipitation assay using a mouse antihuman GBA antibody. No cross-reactivity between mouse beta-glucosidase and human GBA or neutral beta-glucosidase (GBN) was observed. Fifty-two primary, secondary, and tertiary manmouse hybrid lines, derived from three separate fusion experiments, were analyzed for human GBA and enzyme markers for the human chromosomes. Without exception, the presence of human GBA in these hybrid clones was correlated with the presence of human chromosome 1 or its enzymatic markers, phosphoglucomutase 1 (PGM1), and fumarate hydratase (FH). All other human chromosomes were eliminated by the independent segregation of GBA and their respective enzyme markers and/or chromosomes. Using a RAG X human fibroblast line with a mouse-human rearrangement of human chromosome 1, the locus for GBA was limited to the region 1p11 to 1qter.     

Massive peptide sharing between viral and human proteomes

Thirty viral proteomes were examined for amino acid sequence similarity to the human proteome, and, in parallel, a control of 30 sets of human proteins was analyzed for internal human overlapping. We find that all of the analyzed 30 viral proteomes, independently of their structural or pathogenic characteristics, present a high number of pentapeptide overlaps to the human proteome. Among the examined viruses, human T-lymphotropic virus 1, Rubella virus, and hepatitis C virus present the highest number of viral overlaps to the human proteome. The widespread and ample distribution of viral amino acid sequences through the human proteome indicates that viral and human proteins are formed of common peptide backbone units and suggests a fluid compositional chimerism in phylogenetic entities canonically classified distantly as viruses and Homo sapiens. Importantly, the massive viral to human peptide overlapping calls into question the possibility of a direct causal association between virus-host sharing of amino acid sequences and incitement to autoimmune reactions through molecular recognition of common motifs.     

Structure of the human genomic region homologous to the bovine prochymosin-encoding gene

Two human genomic libraries were probed with bovine prochymosin (bPC) cDNA. Recombinant clones covering a genomic region homologous to the entire coding region and flanking sequences of the bPC gene were isolated. Human sequences homologous to exons of the bPC gene are distributed in a DNA fragment of 10 kb. Alignment of the human sequences and the exons of bPC reveals that the human 'exons' 1-3, 5 and 7-9 have sizes identical to the corresponding bovine exons, but a nucleotide (nt) has been deleted in the human exon 4 and two nt in the human exon 6. The aligned human sequence and the coding part of bPC gene share 82% nt homology, the value ranging, in separate exons, from 76 (exon 1) to 84% (exons 5 and 6). 150 bp of 5'-flanking sequence of the human gene has 75% homology to the corresponding region of bPC gene and contains a TATA-box in a similar position. A 1-nt deletion in the human exon 4 would shift the translational reading frame of a putative human PC mRNA relative to bPC mRNA, and result in an in-phase terminator spanning codons 163 and 164 in bPC mRNA. Another terminator in-phase with the amino-acid sequence encoded by the bPC gene occurs in the human exon 5 and the second frameshift mutation in exon 6. Thus, the nt sequence analysis of the human genomic region has revealed the presence of mutations that have rendered it unable to produce a full-length protein homologous to bPC and, therefore, we refer to this gene as a human prochymosin pseudogene (hPC psi). Blot-hybridization analysis of human genomic DNA indicates that hPC psi is a single gene in the human genome.     

The primary structure of human chromogranin A and pancreastatin

A full-length clone encoding human chromogranin A has been isolated from a lambda gt10 cDNA library of a human pheochromocytoma. The nucleotide sequence reveals that human chromogranin A is a 439-residue protein preceded by an 18-residue signal peptide. Comparison of the protein sequence of human chromogranin A with that of bovine chromogranin A shows high conservation of the NH2-terminal and COOH-terminal domains as well as the potential dibasic cleavage sites, whereas the middle portion shows remarkable sequence variation (36%). This part of human chromogranin A contains a sequence homologous to porcine pancreastatin at residues 250-301. The sequence variation in this part of human chromogranin A compared to porcine pancreastatin is 32% and thus of the same magnitude as that between human and bovine chromogranin A. Therefore, the difference between porcine pancreastatin and the corresponding portions of bovine or human chromogranin A can be explained by species variation, suggesting that pancreastatin is derived from chromogranin A itself rather than a protein that is only similar to chromogranin A. Moreover, the pancreastatin sequence contained in human chromogranin A is flanked by sites for proteolytic processing. Together, these observations suggest that human chromogranin A may be the precursor for a human pancreastatin molecule and possibly for other, as yet unidentified, biologically active peptides.     

Assignment of the structural gene for human beta glucuronidase to chromosome 7 and tetrameric association of subunits in the enzyme molecule.

The structural locus for human beta glucuronidase is assigned to chromosome 7, a localization based upon concordant segregation of the expression of the human enzyme and the presence of human chromosome 7 in somatic cell hybrid clones derived independently from fusions of different human and mouse cells. Hybrid clones containing only human chromosome 7 are included in this study. Electrophoresis of beta glucuronidase also has revealed that human beta glucuronidase has a tetrametric structure.     

人B细胞永生化研究进展

人源单克隆抗体具有免疫原性低、半衰期长等优势,成为了体内应用中不可或缺的生物制剂.人类抗体库为人源单克隆抗体的制备提供了丰富的来源,人B细胞永生化是获得人类抗体库的潜在有效方法,可应用于人源单克隆抗体的制备.由于各平台均有亟待解决的问题,基于人B细胞永生化的抗体制备尚局限在实验室研究阶段,且目前尚缺乏一篇系统综述以明确...     

Ergological viewpoint in real-life study

I think that real-life studies on human work must be done, if possible, not objectively, but subjectively from an ergological viewpoint. Essentially, I consider ergology as the biology of human living and work, along German biologist Haeckel's idea. He considered ergology a field of anthropology. The instinctive (genetic) element and the learned (environmental) element constitute human behavior. It is conceivable that the adaptation by human learnability has today brought about high-tech society, and genetic human attributes (human nature) have been adapted to the living environment of hunters and gatherers, which has been long-lasting in human history. Hunters-gatherers form a band consisting of about 50 (30-100) persons and move in a more or less vaguely defined territory (1,000-3,000 km2). The unsuitableness of human nature for modern scientific civilization has caused various problems. Always keeping human nature in mind when considering human living and work is the philosophical background of human ergology. Two real-life working conditions in agriculture, the packing of leeks and promoting a system for securing employees in strawberry production, are presented.     

On the possible presence of a beta 2-microglobulin-like protein in extracts of livers from normal chickens and chickens with erythroblastosis-III. Immunological relationship to serum albumin of a small molecular weight human liver protein

Human liver contains a small molecular weight protein (SMWP) previously shown to be biochemically homologous with a chicken liver protein in terms of its amino acid residues. This human protein, which reacts immunologically as a human serum protein, has been tested for its reactions against a battery of antisera that react specifically with many of the human serum proteins. Material prepared from four human livers gave strong reactions in double gel immunodiffusion with an antiserum against human albumin. One of the liver preparations reacted weakly with antiserum against human ferritin; this ferritin is assumed to be a contaminant. Because of the biochemical homology of human liver SMWP with chicken liver SMWP the latter would be expected to react immunologically as serum albumin.