Showing papers by "National Institutes of Health published in 1982"
TL;DR: It is now proposed that over 30% of bone marrow blasts will suffice for the diagnosis of acute myeloid leukaemia (AML) in any of its forms (M1‐M6) and recognition of the new category, RAEB in transformation, may throw light on the pathogenesis of AML.
Abstract: New diagnostic criteria for the diagnosis of the various myelodysplastic syndromes (MDS) are proposed, and a detailed description is given of the features that may help define MDS. Five MDS are described: (1) refractory anaemia (RA), (2) RA with ring sideroblasts, (3) RA with excess of blasts (RAEB), (4) chronic myelomonocytic leukaemia (CMML), and (5) RAEB 'in transformation'. One of the main distinguishing features of these conditions is the proportion of blast cells in the peripheral blood (PB) and/or bone marrow (BM). The morphological features of the blast cells that are of diagnostic importance have been redefined. In RA, with or without ringed sideroblasts, there are fewer than 1% of blasts in the PB and fewer than 5% in the BM; RAEB is defined as having between 5% and 20% of blasts in the BM and fewer than 5% in the PB; RAEB in transformation (a newly defined category) will be considered when any of the following features is present: (i) more than 5% of blasts in the PB, (ii) 20-30% in the BM, and (iii) the presence of Auer rods in granulocyte precursors in BM or PB. In accordance with these newly defined criteria, it is now proposed that over 30% of bone marrow blasts will suffice for the diagnosis of acute myeloid leukaemia (AML) in any of its forms (M1-M6). The proposed descriptions of the MDS should facilitate the interpretation of data emerging from cytogenetic and bone marrow culture studies and the search for features of possible prognostic significance. Recognition of the new category, RAEB in transformation, may throw light on the pathogenesis of AML.
3,764 citations
TL;DR: Results suggest that small numbers of substitutions in antibodies, such as those presumably introduced by somatic mutation, may in some situations be effective in altering antigen-binding specificity.
Abstract: S107, a phosphocholine-binding myeloma protein, has been cloned in soft agar, and an antigen-binding variant has been isolated and characterized. The variant does not bind phosphocholine attached to carrier or as free hapten in solution but does retain antigenic determinants (idiotypes) of the parent. Chain recombination experiments suggest that the defect in binding is entirely in the heavy chain. Amino acid sequence analysis showed a single substitution--glutamic acid to alanine at position 35--in the first hypervariable or complementarity-determining region. In terms of the three-dimensional model of the phosphocholine-binding site, glutamic acid-35 provides a hydrogen bond to tyrosine-94 of the light chain that appears to be critical for stability of this portion of the binding site. The removal of this bond and the presence of the smaller alanine side chain is thus consistent with the loss in binding activity. These results suggest that small numbers of substitutions in antibodies, such as those presumably introduced by somatic mutation, may in some situations be effective in altering antigen-binding specificity.
2,639 citations
TL;DR: Three new visual acuity charts facilitate quantitative use ofVisual acuity test results by providing high-contrast lettering on washable white polystyrene on which to test right and left eyes.
2,065 citations
TL;DR: Evidence is presented that the LAK system is a phenomenon distinct from either NK or CTL systems that probably accounts for a large number of reported nonclassical cytotoxicities and may be functional in immune surveillance against human solid tumors.
Abstract: Activation in lectin-free interleukin 2 (IL-2) containing supernatants of peripheral blood mononuclear leukocytes (PBL) from cancer patients or normal individuals resulted in expression of cytotoxicity toward 20 of 21 natural killer (NK)-resistant fresh solid tumor cells tested. Fresh solid tumor cells were resistant to NK-mediated lysis in 10 autologous patients' PBL-tumor interactions, and from 17 normal individuals tested against 13 allogeneic fresh tumors. Culture of PBL in IL-2 for 2-3 d was required for the lymphokine activated killers (LAK) to be expressed, and lytic activity toward a variety of NK-resistant fresh and cultured tumor targets developed in parallel. Autologous IL-2 was functional in LAK activation, as well as interferon-depleted IL-2 preparations. Irradiation of responder PBL before culture in IL-2 prevented LAK development. Precursors of LAK were present in PBL depleted of adherent cells and in NK-void thoracic duct lymphocytes, suggesting that the precursor is neither a monocyte nor an NK cell. LAK effectors expressed the serologically defined T cell markers of OKT.3, Leu-1, and 4F2, but did not express the monocyte/NK marker OKM-1. Lysis of autologous fresh solid tumors by LAK from cancer patients' PBL was demonstrated in 85% of the patient-fresh tumor combinations. Our data present evidence that the LAK system is a phenomenon distinct from either NK or CTL systems that probably accounts for a large number of reported nonclassical cytotoxicities. The biological role of LAK cells is not yet known, although it is suggested that these cells may be functional in immune surveillance against human solid tumors.
2,043 citations
TL;DR: Experiments are presented that localize the genetic lesion that led to activation of the oncogene that affects the structure of theOncogene-encoded protein.
Abstract: The oncogene of the human EJ bladder carcinoma cell lines arose via alteration of a cellular proto-oncogene. Experiments are presented that localize the genetic lesion that led to activation of the oncogene. The lesion has no affect on levels of expression of the oncogene. Instead, it affects the structure of the oncogene-encoded protein.
1,269 citations
TL;DR: A single amino acid substitution appears to be sufficient to confer transforming properties on the gene product of the T24 human bladder carcinoma oncogene.
Abstract: The genetic change that leads to the activation of the oncogene in T24 human bladder carcinoma cells is shown to be a single point mutation of guanosine into thymidine. This substitution results in the incorporation of valine instead of glycine as the twelfth amino acid residue of the T24 oncogene-encoded p21 protein. Thus, a single amino acid substitution appears to be sufficient to confer transforming properties on the gene product of the T24 human bladder carcinoma oncogene.
1,255 citations
TL;DR: Modelling indicated that limb-sparing surgery, radiation therapy, and adjuvant chemotherapy appear capable of successfully treating the great majority of adult patients with soft tissue sarcomas of the extremity.
Abstract: Between May 1975 and April 1981, 43 adult patients with high-grade soft tissue sarcomas of the extremities were prospectively randomized to receive either amputation at or above the joint proximal to the tumor, including all involved muscle groups, or to receive a limb-sparing resection plus adjuvant radiation therapy. The limb-sparing resection group received wide local excision followed by 5000 rads to the entire anatomic area at risk for local spread and 6000 to 7000 rads to the tumor bed. Both randomization groups received postoperative chemotherapy with doxorubicin (maximum cumulative dose 550 mg/m2), cyclophosphamide, and high-dose methotrexate. Twenty-seven patients randomized to receive limb-sparing resection and radiotherapy, and 16 received amputation (randomization was 2:1). There were four local recurrences in the limb-sparing group and none in the amputation group (p1 = 0.06 generalized Wilcoxon test). However, there were no differences in disease-free survival rates (71% and 78% at five years; p2 = 0.75) or overall survival rates (83% and 88% at five years; p2 = 0.99) between the limb-sparing group and the amputation treatment groups. Multivariate analysis indicated that the only correlate of local recurrence was the final margin of resection. Patients with positive margins of resection had a higher likelihood of local recurrence compared with those with negative margins (p1 less than 0.0001) even when postoperative radiotherapy was used. A simultaneous prospective randomized study of postoperative chemotherapy in 65 patients with high-grade soft-tissue sarcomas of the extremities revealed a marked advantage in patients receiving chemotherapy compared with those without chemotherapy in three-year continuous disease-free (92% vs. 60%; p1 = 0.0008) and overall survival (95% vs. 74%; p1 = 0.04). Thus limb-sparing surgery, radiation therapy, and adjuvant chemotherapy appear capable of successfully treating the great majority of adult patients with soft tissue sarcomas of the extremity.
1,202 citations
TL;DR: Phosphorylation was specifically stimulated by insulin in a dose-dependent fashion after 1 and 15 minutes of hormone treatment, whereas human growth hormone was without effect, suggesting this phosphorylation may be a very early event in insulin action.
Abstract: Cultured human lymphocytes and rat hepatoma cells were labeled with [32P]orthophosphate and the insulin receptor subunits identified by immunoprecipitation and sodium dodecyl sulfate-gel electrophoreses. In both cell types the 95,000-dalton (beta) subunit of the insulin receptor was selectively phosphorylated. Phosphorylation was specifically stimulated by insulin in a dose-dependent fashion after 1 and 15 minutes of hormone treatment, whereas human growth hormone was without effect. This phosphorylation may be a very early event in insulin action.
1,088 citations
TL;DR: Whether neoplasms are unicellular or multicellular in their origin, the process of tumor evolution and progression can rapidly generate biological diversity within and among different metastatic foci.
Abstract: Whether neoplasms are unicellular or multicellular in their origin, the process of tumor evolution and progression can rapidly generate biological diversity. Metastases result from the survival and proliferation of specialized subpopulations of cells within the parent tumor. Metastases may have a clonal origin and different metastases may develop from different progenitor cells. However, as with the primary tumor, the origin of metastases is unimportant since the process of tumor evolution and progression can generate biological diversity within and among different metastatic foci.
952 citations
TL;DR: In a family study of 1,254 adult relatives of patients and controls, lifetime prevalences of major affective disorder (including schizoaffective) were 37%, 24%, 25%, 20% and 7% in relatives of probands with schizoAffective, bipolar I, bipolar II, and unipolar disease, and normal controls.
Abstract: • In a family study of 1,254 adult relatives of patients and controls, lifetime prevalences of major affective disorder (including schizoaffective) were 37%, 24%, 25%, 20% and 7% in relatives of probands with schizoaffective, bipolar I, bipolar II, and unipolar disease, and normal controls. These data were compatible with the different affective disorders representing thresholds on a continuum of underlying multifactorial vulnerability. In this model, schizoaffective illness represents greatest vulnerability, followed by bipolar I and bipolar II, then unipolar illnesses. Alcoholism, drug abuse, and sociopathy were not more frequent in relatives of patients v relatives of controls. Sex-related transmission of morbid risk was not present. Morbid risk was 74% to offspring of two ill parents, and 27% to offspring of one ill parent. Nationality and age at time of interview seem to be nongenetic factors that affect frequency of diagnosis.
939 citations
TL;DR: The life history of aggression and history of suicidal behavior in 12 subjects with borderline personality disorders without major affective disorder were examined, and Histories of aggressive behaviors and of suicide attempts were significantly associated with each other.
Abstract: In an earlier, separate study, the authors found that human aggression and suicide (a specific aggression-related behavior) were associated with lower levels of CSF 5-hydroxyindoleacetic acid (5-HIAA), a serotonin metabolite. That study focused on subjects with personality disorders without affective illness. In the present study they examine the life history of aggression and history of suicidal behavior in 12 subjects with borderline personality disorders without major affective disorder. Histories of aggressive behaviors and of suicide attempts were significantly associated with each other, and each was significantly associated with lower 5-HIAA levels. Altered serotonin metabolism may be a highly significant contributing factor to these behaviors in whatever diagnostic group they occur. Language: en
TL;DR: Observations that activated lymphocytes may be sensitive to the lytic effects of glucocorticoids suggest that under certain situations the elimination of selected subsets of cells may be a relevant mechanism of corticosteroid-mediated immunoregulation in man.
Abstract: Glucocorticoids have profound and complex effects on the human immune response. However, the precise mechanisms of the corticosteroid-induced immunoregulation in man have not been precisely defined. Intracytoplasmic corticosteroid-specific receptors appear to be an important common pathway for steroid-induced changes, but variations of receptor parameters do not account for the multifaceted effects on the immune system. Human circulating mononuclear cells redistribute out of the intravascular compartment following treatment with corticosteroids. Although certain components at this redistribution phenomenon have been well-characterized, the importance of this compartmental cellular shift with respect to the mechanisms of corticosteroid-induced immunoregulation are less well-defined. Recent observations that activated lymphocytes may be sensitive to the lytic effects of glucocorticoids suggest that under certain situations the elimination of selected subsets of cells may be a relevant mechanism of corticosteroid-mediated immunoregulation in man. Corticosteroid-mediated effects on monocyte function may be an important mechanism of drug-induced immunoregulation in monocyte-dependent responses. In some experimental conditions, corticosteroids inhibit Interleukin 1 production by monocytes. The immunoregulatory effects of corticosteroids on lymphocyte immune responses are complex. In vitro corticosteroids appear to selectively affect early immunoregulatory events as opposed to altering an established response. Multiple sites of steroid-induced modulations of human B cell responses have been defined.
TL;DR: It is apparent that phenyl-SepHarose offers several advantages over phenothiazine-Sepharose for affinity purification of calmodulin, and the time required for this procedure is substantially less than that of previously described procedures.
TL;DR: The first motor cortex of the rat was identified as the region from which movements could be evoked by the lowest intensity of electrical stimulation and was correlated with Cytoarchitecture in the frontal and parietal cortex.
Abstract: The first motor (MI) cortex of the rat was identified as the region from which movements could be evoked by the lowest intensity of electrical stimulation. The location of this region was correlated with cytoarchitecture in the frontal and parietal cortex. Two frontal areas can be discerned in Nissl-stained sections: (1) the medial agranular field, marked by a pale-staining layer III and a compact layer II, and (2) the lateral agranular field, which has more homogeneous superficial layers and a broad layer V containing large, densely staining cells. Both of these regions project to the spinal cord and can therefore be included in the somatic sensorimotor cortex. MI in the rat coincides with the lateral agranular field but also overlaps with part of the adjacent granular cortex of the first somatic sensory (SI) representation. We conclude that the rat MI cortex can be identified by microstimulation techniques and by cytoarchitecture in the rat.
TL;DR: In this article, a longitudinal causal model of the reciprocal effects of the substative complexity of work and intellectual flexibility is presented, showing that self-directed work leads to ideational flexibility and to a selfdirected orientation to self and society; oppressive working conditions lead to distress.
Abstract: In earlier work, we assessed a longitudinal causal model of the reciprocal effects of the substative complexity of work and intellectual flexibility. In this paper, we greatly expand the causal model to consider sumultaneously several structural imperatives of the job and three major dimensions of personality-ideational flexibility, a self directed orientation to self and society, and a sense of distress. The analysis demonstrates that the structural imperatives of the job affect personality. Self-directed work leads to ideational flexibility and to a self-directed orientation to self and society; oppressive working conditions lead to distress. These findings strongly support a learning generalization model. Personality, in turn, has important consequences for an individual's place in the job structure and in the system of social stratification. In particular, both ideational flexibility and a self-directed orientation lead, over time, to more responsible jobs that allow greater latitude for occupational ...
TL;DR: Estimates of forces between bilayer vesicles show great sensitivity to the identity of the phospholipid polar group and to the packing of the hydrocarbon acyl chains, and on major implication of this is the likelihood of local structural changes and lipid segregation in the area of closest approach of interacting vesicle of mixedospholipids.
TL;DR: Findings further extend the association between intraneuronal aluminum and NFT formation and support the hypothesis that environmental factors are related to the neurodegenerative changes seen in the Chamorro population.
Abstract: Scanning electron microscopy with energy-dispersive x-ray spectrometry was used to analyze the elemental content of neurofibrillary tangle (NFT)-bearing and NFT-free neurons within the Sommer's sector (H1 region) of the hippocampus in Guamanian Chamorros with amyotrophic lateral sclerosis and parkinsonism-dementia and in neurologically normal controls. Preliminary data indicate prominent accumulation of aluminum within the nuclear region and perikaryal cytoplasm of NFT-bearing hippocampal neurons, regardless of the underlying neurological diagnosis. These findings further extend the association between intraneuronal aluminum and NFT formation and support the hypothesis that environmental factors are related to the neurodegenerative changes seen in the Chamorro population.
TL;DR: The nucleotide sequence of a complete cDNA copy of enkephalin precursor mRNA from human phaeochromocytoma is reported and shows that the precursor is 267 amino acids long and contains six interspersed Met-enkephaline sequences and one Leu-encephalin sequence.
Abstract: The nucleotide sequence of a complete cDNA copy of enkephalin precursor mRNA from human phaeochromocytoma is reported The corresponding amino acid sequence shows that the precursor is 267 amino acids long and contains six interspersed Met-enkephalin sequences and one Leu-enkephalin sequence Five of the seven enkephalins are flanked on both sides by pairs of basic amino acid residues The precursors does not contain the sequences of the opioid peptides, dynorphin, alpha-neo-endorphin or beta-endorphin
TL;DR: The findings suggest that the elements required for phosphorylation are associated with the plasma membrane of the cell and that specific phosphorylated of the insulin receptor on tyrosine residues can be activated in a solubilized preparation.
Abstract: Insulin forms a complex with its receptors on the plasma membrane of cells and initiates a series of biochemical events which lead to the hormone's recognized effects1,2. The exact mechanism that initiates these events is unknown. We previously reported that insulin stimulates the phosphorylation of the 95,000 molecular weight (Mr) (β) subunit of its own receptor in intact cells and proposed that this phosphorylation reaction could be a very early step in insulin action3. To clarify the molecular basis of this reaction, we have now investigated the phosphorylation of insulin receptor in a cell-free system. Using [γ-32P]ATP in solubilized and partially purified receptor preparations from rat liver plasma membrane, we find that both the α and β subunits of the insulin receptor are phosphorylated. Furthermore, insulin stimulates the incorporation of 32P into both receptor subunits in a specific and dose-dependent manner. Phosphoamino acid determination of the β subunit after insulin stimulation reveals only phosphotyrosine. These findings suggest that the elements required for phosphorylation are associated with the plasma membrane of the cell and that specific phosphorylation of the insulin receptor on tyrosine residues can be activated in a solubilized preparation.
TL;DR: A transforming gene isolated from T24 human bladder carcinoma cells is closely related to the BALB murine sarcoma virus (MSV) onc gene (v-bas), which implies that rather subtle genetic alterations have led to the activation of the normal human homologue of v-bas as a human transforming gene.
Abstract: A transforming gene isolated from T24 human bladder carcinoma cells is closely related to the BALB murine sarcoma virus (MSV) onc gene (v-bas). This transforming gene is localized to a 4.6 kilobase pair (kbp) region and is expressed as a 1.2-kbp polyadenylated transcript, which contains v-bas related sequences. Moreover, antisera known to detect the immunologically related onc gene products of BALB- and Harvey-MSVs recognized elevated levels of a related protein in T24 cells. The normal human homologue of v-bas was found to be indistinguishable from the T24 oncogene by heteroduplex and restriction enzyme analysis. These results imply that rather subtle genetic alterations have led to the activation of the normal human homologue of v-bas as a human transforming gene.
TL;DR: This chapter discusses the structure and organization of mammalian, highly repeated sequences at the molecular level with a description of tandemly repeated sequences, that are, satellites, and the segments that are interspersed among other genomic DNA sequences.
Abstract: Publisher Summary This chapter discusses the structure and organization of mammalian, highly repeated sequences at the molecular level. There is a description of tandemly repeated sequences, that are, satellites, and the segments that are interspersed among other genomic DNA sequences. The methods for the analysis of repeated DNA sequences are measurement of DNA renaturation kinetics and isopycnic centrifugation in gradients of CsCl and CsSO4. Eukaryote genomes can be divided into classes of DNA sequences according to the reiteration frequency. Many highly repeated sequences are in long tandem arrays. Some repetitive sequences are dispersed throughout major portions of genomes amid either other repeated sequences or sequences present only once per genome, that are, uniquesequences. The characteristic organizational feature of satellites and cryptic satellites is the tandem repetition of a unit DNA sequence. Satellite arrays resist separation by isopycnic centrifugation and instead remain within the main density fraction of genomic DNA. The repeat unit and its tandem organization can be revealed by restriction endonuclease digestion.
TL;DR: In this paper, the chronoamperometric current at a stationary finite disk electrode is studied using both analytical and digital simulation techniques, and the exact long-time expansion of the current is obtained and its short-time behavior is considered.
TL;DR: Investigation of the cellular homologue, c-myc, of the transforming gene of avian myelocytomatosis virus and its role in the pathogenesis of chicken B-cell lymphomas induced by the non-acute leukosis virus finds that any structural alteration at the genomic level could account for the increased expression of c- myc in HL-60.
Abstract: Cellular onc genes are a group of evolutionarily conserved sequences which are homologous to the transforming genes (v-onc) of oncogenic retroviruses1. Their function in normal cells is not yet known, but the sequence homology between viral and cellular onc genes is consistent with the idea that neoplastic transformation may, in some cases, be due to increased levels of cellular onc gene expression. The cellular homologue, c-myc, of the transforming gene of avian myelocytomatosis virus (MC29)1,2 is involved in the pathogenesis of chicken B-cell lymphomas induced by the non-acute leukosis virus (RAV-2)3–6, and in these tumours, c-myc expression is enhanced by the nearby integration of the RAV-2 terminal repeat region3–6. Transcripts from the c-myc gene are detectable in a variety of human cells7,8, and increased levels of myc mRNA have been occasionally detected in some neoplastic tissues7,8. The highest levels have been detected in the cell line HL-60 (ref. 8) derived from neoplastic cells from a patient with acute promyelocytic leukaemia (APL)9. We have now investigated whether any structural alteration at the genomic level could account for the increased expression of c-myc in HL-60 and report here that the c-myc gene is stably amplified in HL-60 DNA. Amplification was also detected in primary uncultured leukaemic cells from the same individual, suggesting that the c-myc amplification may have been involved in the leukaemic transformation in this case.
TL;DR: The finding of HTLV antibodies in some of the normal population in the Caribbean and Japan, and the clustering of a specific form of T‐cell leukemia/lymphoma in these virus‐endemic areas, suggest that HTLV infection may be associated with the occurrence of a distinctive clinico‐pathologic entity.
Abstract: Type-C RNA tumor viruses have been implicated in the etiology of naturally occurring leukemias and lymphomas of animals. Human T-cell leukemia/lymphoma virus (HTLV) is the first human virus of this class consistently identified in association with a specific type of human leukemia/lymphoma. The isolation of HTLV was made possible by the ability to grow mature T-cells in tissue culture usually with T-cell growth factor (TCGF). We now report a cluster of adult T-cell leukemia/lymphoma among Blacks from the Caribbean in which all eight cases are positive for HTLV virus and/or antibody. These patients have disease that appears indistinguishable from Japanese adult T-cell leukemia/lymphoma which, as we have also reported, is associated with HTLV in over 90% of cases. The finding of HTLV antibodies in some of the normal population in the Caribbean and Japan, and the clustering of a specific form of T-cell leukemia/lymphoma in these virus-endemic areas, suggest that HTLV infection may be associated with the occurrence of a distinctive clinico-pathologic entity.
TL;DR: Discrepancies between the symptoms of depression, as found in a self-report questionnaire, and the diagnosis of major depression as made by the Research Diagnostic Criteria occurred in a community survey.
Abstract: • Discrepancies between the symptoms of depression, as found in a self-report questionnaire (Center for Epidemiologic Studies-Depression Scale [CES-D]), and the diagnosis of major depression as made by the Research Diagnostic Criteria (RDC) occurred in a community survey. The discrepancies can be explained by the subject's psychiatric or medical disorders other than depression, by nay saying during the interview, or by the exclusion criteria of the RDC (duration of symptoms, role impairment, or help seeking) that are not part of the CES-D. Results show that the discrepancies can be readily explained.
TL;DR: The anatomy, physiology and biochemistry of opiomelanotropinergic neurons are reviewed and the implications of multi-neurotransmitter and multi-hormone neurons and cells are discussed.
TL;DR: Observations that P elements are present in 30-50 copies per haploid genome in all P strains examined and apparently are missing entirely from all M strains examined strongly support the P factor hypothesis for the mechanistic basis of P-M hybrid dysgenesis.
TL;DR: Results indicate that high levels of a gene product encoded by a normal human oncogene can induce tumorigenic transformation.
Abstract: A normal human gene homologous to the p21 ras oncogene of Harvey murine sarcoma virus induced oncogenic transformation and high p21 ras levels in murine fibroblasts when this gene was ligated to a control element (the long terminal repeat) from a murine or feline retrovirus. These results indicate that high levels of a gene product encoded by a normal human oncogene can induce tumorigenic transformation.
TL;DR: A simple new agar medium containing L-canavanine, glycine, and bromthymol blue was found to give a clearer and more accurate distinction between serotype A or D and serotype B or C (C. neoformans var. gattii) than creatinine-dextrose-bromthyl blue or glycine-cycloheximide-phenol red media.
Abstract: A simple new agar medium containing L-canavanine, glycine, and bromthymol blue was found to give a clearer and more accurate distinction between serotype A or D (Cryptococcus neoformans var. neoformans) and serotype B or C (C. neoformans var. gattii) than creatinine-dextrose-bromthymol blue or glycine-cycloheximide-phenol red media. Among 143 isolates of serotype A or D and 70 isolates of serotype B or C, the new medium correlated completely with the serotype, whereas nearly 11% of these isolates gave discrepant reactions with creatinine-dextrose-bromthymol blue and glycine-cycloheximide-phenol red media.
TL;DR: Laminin, and to a lesser degree fibronectin, may enhance neurite growth of human sensory neurons in synergy with NGF, and increase adhesion of dissociated sensory neurons cultured on collagen coated surfaces.
Abstract: The effect of mouse nerve growth factor (NGF) on cultured human fetal sensory neurons was assayed by measuring neurite length, density and rate of growth. Addition of NGF increased adhesion of dissociated sensory neurons cultured on collagen coated surfaces. Almost all neurons of 9 to 10 week old fetuses are postmitotic, contain neuron-specific enolase, (an enzyme linked to differentiation), and require NGF for optimal neurite growth. Sensory ganglia re-explanted on collagen showed maximal neurite length and density when treated with 1 ng/ml of NGF. Neurite density was reduced considerably in the absence of mouse NGF and was almost abolished by addition of antimouse NGF antibodies. Surfaces coated with the matrix glycoproteins laminin or fibronectin further stimulated neurite growth of ganglia in the presence of NGF. Increasing amounts of matrix proteins could partly compensate for the absence of mouse NGF or the inhibition of NGF activity by antibodies. Stimulation of neurite growth by matrix proteins was time-dependent, and neurites showed maximum length at 10 days (2 to 3 mm). Neurite growth was more pronounced with laminin than with fibronectin and collagen, and antibodies to laminin suppressed all neurite growth. In the presence of a constant amount of NGF, mean neurite growth reached 26 microns/hr (at 1 day), and was 2.1 and 1.7 times faster on laminin and fibronectin (respectively) than on collagen. Thus, laminin, and to a lesser degree fibronectin, may enhance neurite growth of human sensory neurons in synergy with NGF.