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Biomedical subjects

A Marks

Publications and source records attributed to A Marks.

At least 109 records · Page 6Linked to original sources

S-100 protein in tumors of cartilage and bone. An immunohistochemical study.

Using the peroxidase-antiperoxidase (PAP) immunohistochemical method, S-100 protein was found in well-differentiated chondrocytes of chondroma, chondroblastoma, mesenchymal chondrosarcoma, and osteosarcoma. It was not detected in osteoma, osteoblastoma, giant cell tumor, and Ewing's tumor. The presence of S-100 protein in tumorous chondrocytes and chondroblasts suggests that this protein may be a marker of chondrocyte origin and should not be considered a specific marker for nerve tissue.

Adolescent↗

The synthesis of the brain specific S100 protein in colcemid resistant mutants of rat glial cells.

We have isolated two colcemid-resistant mutant sublines, CMR (7A) and CMR (7B), from rat glial cells, C6, using multiple consecutive selections with increasing concentrations of colcemid. The mutant sublines show a decreased uptake of [3H]colchicine but have no apparent defect in the cytoplasmic binding of the drug. The synthesis of the brain-specific S100 protein is less sensitive to colcemid inhibition in the mutant cell lines than in parental C6 cells, suggesting that colcemid must enter the cell to inhibit S100 protein synthesis.

Animals↗

Characterization of idiotopes on MOPC 315 IgA using monoclonal antiidiotypic antibodies.

The isologous antiidiotypic response in BALB/c mice to immunization with the DNP-binding IgA myeloma protein, MOPC 315, alters the expression of the anti-DNP antibody repertoire and confers immunity against MOPC 315 myeloma tumors. In order to characterize the idiotopes on MOPC 315 IgA which elicit this response we have isolated four monoclonal antiidiotypic antibodies (AIA) D10 (IgG2a), A2(IgG1), G3 (IgG2b) and F1 (IgG2a), produced by splenocytes of BALB/c mice immunized with MOPC 315 IgA in three independent fusion experiments. These AIA react with MOPC 315 IgA, reassociated H315 L315 and FV31¿5 but not with free H315, L315, VH315 or VL315. In addition the AIA do not react with the closely related DNP-binding IgA myeloma protein, MOPC 460, suggesting that they are directed against private idiotopes on MOPC 315 IgA. These idiotopes can be divided into two groups. Group I, defined by D10, A2 and G3 consists of two overlapping idiotopes, one of which is related to the hapten-binding site. The two idiotopes are formed by an interaction of amino acids in H315 and L315. Group II defined by F1 consists of one idiotope which is related to the hapten-binding site. This idiotope is comprised of an amino acid sequence on H315 which requires an interaction with either L315 or L460 for expression. A2 and G3 react identically with the same idiotope but were derived from two independent fusion experiments. This indicates an identity of AIA clonotypes among individual mice and suggests that the isologous AIA response to MOPC 315 IgA is restricted.

Animals↗

Assessment of health needs and willingness to utilize health care resources of adolescents in a suburban population.

We investigated whether adolescents living in a middle-class suburb believed that their health needs were being met, and the extent to which they were willing to utilize local health care resources for a range of problems. Self-administered, anonymous questionnaires were completed by 649 students in grades 9 through 12. The mean age of respondents was 15.4 years; 52% were female, and 95% white. They had ready access to medical care: 90% used a specific private physician. From a list of 15 health problems, 60% indicated that they had seen a health provider for at least one of them, most often for stomach pains (22%), headaches (18%), and coughing (16%). From an identical list, 48% indicated that there was at least one problem for which they had never seen a health provider but would like to, most often for a weight problem (14%), birth control (10%), and emotional upset (9%). Although 20% regularly used illegal drugs, 24% were sexually active, and 38% thought they had a weight problem, only 1%, 4%, and 10%, respectively, had sought care for these matters. A majority of students would not choose to go to a private physician for care related to sexuality, substance abuse, or emotional upset, and would not be willing to seek care for these problems with their parents' knowledge. Ready access to private primary care did not assure attention to important health needs among these suburban adolescents.

Adolescent↗

Origin of the desmoplasia in desmoplastic malignant melanoma.

Four cases of desmoplastic malignant melanoma were examined light microscopically and immunohistochemically. Electron microscopy was performed in three cases. Light microscopy showed that all tumors were composed of neoplastic spindle cells that infiltrated between mature collagen bundles in the reticular dermis. Some of the spindle cells had bizarre nuclei, whereas other spindle cells resembled normal fibroblasts. Melanin could not be demonstrated in any of the tumors by histochemical techniques. Electron microscopic examination of the spindle cells showed prominence of rough endoplasmic reticulum, which was dilated and filled with flocculent material and occasional collagen fibrils. The same cells contained aggregates of non-membrane-bound melanin granules and pre-melanosomes. Some cells also showed features of myofibroblasts. Immunoperoxidase staining with anti-S100 protein antibody demonstrated positivity of the spindle cells as well as of melanocytes in the basal layer of the epidermis. Scar tissue and fibroblasts did not stain. These findings show that the desmoplastic component of these malignant melanomas derives from melanocytes that have undergone adaptive fibroplasia. Therefore, in assessing depth of invasion in a malignant melanoma, measurements should include the desmoplastic areas.

Adult↗

Role of antibody to S100 protein in diagnostic pathology.

Normal tissues and various tumors were examined for S100 protein, using anti-S100 protein antiserum, in an immunoperoxidase reaction. Among normal tissues, in addition to the previously reported presence of S100 protein in some neurons, glial, and Schwann cells of the nervous system, melanocytes and Langerhans cells of the skin, interdigitating reticulum cells of lymph nodes, and chondrocytes, we demonstrated it in myoepithelial cells and ducts of sweat glands, salivary glands, and the breast, serous glands of the lung, fetal neuroblasts, and sustentacular cells of the adrenal medulla. Among neoplasms, S100 protein previously has been reported in neurogenic tumors, melanomas, and neuroblastomas; we have demonstrated it in mixed sweat gland tumors, histiocytosis X, pleomorphic adenomas of the salivary gland, medullary carcinomas of the breast, bronchioloalveolar carcinomas of the lung, sustentacular cells of pheochromocytomas, teratomas of the ovary, and tumors of cartilage (enchondromas, osteochondromas, and chondrosarcomas). With S100 protein producing tumors, a normal progenitor cell was identified, indicating that demonstration of S100 protein in tumors confirmed their origin.

Carcinoma↗

Distribution of immunoreactive S-100 protein in pediatric brain tumors.

The distribution of S-100 proteins was examined in 98 pediatric brain neoplasms with rabbit antiserum to S-100 protein, utilizing the peroxidase-antiperoxidase (PAP) immunohistochemical technique. Positive cytoplasmic immunoreactivity was present in 22 of 24 astrocytomas, both oligodendrogliomas, eight of 13 ependymomas, all 11 choroid plexus tumors, all nine schwannomas, two of six meningiomas, and both meningeal melanomas. Mixed cytoplasmic immunoreactivity was present in both gangliogliomas, all seven craniopharyngiomas, and the only hemangioblastoma. No cytoplasmic immunoreactivity was found in primitive neuroectodermal tumors or germinoma. Nuclear immunoreactivity was present in some cases. Because of the broad spectrum of apparent immunoreactivity with S-100 antiserum, S-100 protein cannot be used as a specific marker of glial or Schwann cell tumors.

Astrocytoma↗

Synthesis of S100 protein on free and membrane-bound polysomes of the rabbit brain.

Free and membrane-bound polysomes were isolated from the cerebral hemispheres and cerebellum of the young adult rabbit. The two polysomal populations were translated in an mRNA-dependent cell-free system derived from rabbit reticulocytes. Analysis of the [35S]methionine-labeled translation products on two-dimensional polyacrylamide gels indicated an efficient separation of the two classes of brain polysomes. The relative synthesis of S100 protein by free and membrane-bound polysomes was determined by direct immuno-precipitation of the cell-free translation products in the presence of detergents to reduce nonspecific trapping. Synthesis of S100 protein was found to be twofold greater on membrane-bound polysomes compared with free polysomes isolated from either the cerebral hemispheres or the cerebellum. In addition, the proportion of poly-(A+)mRNA coding for S100 protein was also twofold greater in membrane-bound polysomes compared with free polysomes isolated from the cerebral hemispheres. These results indicate that the cytoplasmic S100 protein is synthesized predominantly on membrane-bound polysomes in the rabbit brain. We suggest that the nascent S100 polypeptide chain translation complex is attached to the rough endoplasmic reticulum by an ionic interaction involving a sequence of 13 basic amino acids in S100 protein.

Animals↗

The structural conservation of S100 protein during evolution: analysis by reactivity with a monoclonal antibody.

A hybridoma cell line producing a monoclonal antibody (A4) against bovine S100 protein has been produced by fusing mouse myeloma P3X63/Ag8 cells with spleen cells from a BALB/c mouse immunized with bovine S100 protein. A4 is of the IgG2b subclass and was purified by affinity chromatography on a protein A-Sepharose column. Brain extracts from several mammalian and one avian species reacted both with polyclonal rabbit anti-S100 protein antiserum and with A4 in a radioimmunoassay. Brain extract from dog was a notable exception. It reacted with the rabbit antiserum but not with A4. Therefore A4 reacts with a common epitope that is present on S100 proteins from different vertebrate species but is absent on dog S100 protein.

Animals↗

S100 protein in human chordoma and human and rabbit notochord.

S100 protein is a protein that has been considered to be specific for tissues of neuroectodermal origin; however, recent studies have demonstrated the presence of S100 protein in mesodermal tissues. Using immunohistochemical methods, we found S100 protein in human chordomas and in human and rabbit notochordal tissue. Our findings suggest that S100 protein is present not only in neuroectodermal tissue but in mesodermal tissue, which develops in close proximity to neuroectoderm.

Animals↗

Arrangement of lambda light chain genes in mutant clones of the MOPC 315 mouse myeloma cells.

The synthesis of lambda light chains and the arrangement of the lambda-chain genes was examined in cells of the mouse myeloma MOPC 315, which is an alpha lambda 2 producer, and in several mutants derived from it. The mutants produce lambda 2 chains only (MOPC 315.26, MOPC 315.34, and MOPC 315.37) or fail to produce alpha and lambda 2 chains (MOPC 315.25 and MOPC 315.36). Messenger RNA from the lambda 2 chain-producing cells directed the synthesis of a lambda 2 chain precursor and a fragment of the lambda 1 chain (lambda 1 F) in a wheat embryo cellfree system, whereas mRNA from the cells that do not produce lambda 2 chains directed the synthesis of lambda 1 F only. DNA from the parental MOPC 315 cells and from the lambda 2 chain-producing cells contained discrete EcoRI restriction fragments coding for rearranged lambda 1 and lambda 23 chain genes and their respective germ-line V and J-C regions. DNA from the no-Ig-producing cells contained fragments coding for the rearranged lambda 1 chain gene and the germ-line V lambda 2 region, but it lacked the sequences coding for the rearranged lambda 2 chain gene and the germ-line V lambda 1 and J-C lambda 1 regions. These results suggest that rearrangements of the lambda 1 and lambda 2 chain genes occur on different chromosomes in MOPC 315 cells and imply that rearrangements of the lambda 1 and lambda 2 chain genes on the same chromosome may be mutually exclusive.

Animals↗

Variants of an interspecies hybridoma with altered tumorigenicity and protective ability against mouse myeloma tumors.

Recent isolates of RX54-3 hybridoma cells (new cells) protect BALB/c mice against subsequent challenge with the tumorigenic myeloma parent cells used to construct this hybridoma. In contrast, hybridoma cells which have been maintained in tissue culture for long periods of time (old cells) are not protective. In the present study, we compared a number of properties of the new and old hybridoma cells and determined which line was more similar to the parent myeloma. We found that new hybridoma cells resembled myeloma cells in: (a) possessing A- and C-type viral particles on transmission electron microscopy and a relatively smooth surface on scanning electron microscopy; (b) being sensitive to a hypotonic solution containing the dye propidium iodide; (c) having similar DNA histograms on flow cytometric analysis; (d) being sensitive to the bacteriocin colicin HSC 10; and (e) being tumorigenic in nude mice. In contrast, old hybridoma cells differed in all of these characteristics from new hybridoma and myeloma cells. Therefore, in order to protect against challenge with the tumorigenic myeloma parent, hybridoma cells must retain properties of that parent.

Animals↗

Influence of familial hypertension on blood pressure during adolescence.

The relationships of familial hypertension and height, weight, and blood pressure (BP) were studied in two adolescent populations. Subjects having hypertensive first-degree relatives were matched to control subjects without such a family history. The group with familial hypertension demonstrated a slightly higher average BP but also had a greater mean body weight and ponderal index than the control group. After controlling for weight, male but not female subjects with a family history of hypertension had a greater prevalence of elevated BP and higher average pressures than controls. The factors of above-average weight and familial hypertension appear to interact so as to produce an excessive prevalence of elevated BP. These trends suggest that teenagers with hypertensive first-degree relatives constitute a special risk group that should be closely monitored.

Adolescent↗

Protective effect of an interspecies hybridoma on the tumorigenicity of mouse myeloma cells.

A rabbit lymphocyte-mouse myeloma hybridoma (RX54-3) was administered to BALB/c mice, in order to determine whether hybridoma cells have any protective effect on the tumorigenicity of the P3X63/Ag8 mouse myeloma cell line, one of the parents of this hybridoma. Two sublines of RX54-3 were studied. (a) "new" cells, which produce rabbit light chains and mouse immunoglobulin, are killed by anti-myeloma cell antiserum and complement and possess a high chromosome count. And (b) "old" cells, which have lost all immunoglobulin-producing capacity, are no longer killed by anti-myeloma cell antiserum and complement and possess a low chromosome count. In contrast to myeloma cells, the hybridoma cells were nontumorigenic in normal BALB/c mice, even at very high cell doses. When hybridoma cells were administered prior to challenge with P3X63/Ag8 myeloma cells, protection against development of myeloma tumors was much more effective with new cells than with old cells. Development of protection was dependent on the dose of hybridoma cells, their route of administration, their viability and ability to divide, and the time interval between administration of the hybridoma and myeloma cells. The protection produced by the new hybridoma cells was comparable to that seen after administration of a subtumorigenic dose of living myeloma cells. With both the hybridoma and myeloma cells, protection was seen only against challenge with P3X63/Ag8 myeloma cells but not against another myeloma tumor. These studies indicate that administration of somatic cell hybrids is an effective method of protecting syngeneic hosts against challenge with mouse myeloma tumor cells.

Animals↗

A monoclonal antiidiotypic antibody to MOPC 315 IgA inhibits the growth of MOPC 315 myeloma cells in vitro.

Spleen cells from BALB/c mice immunized with MOPC 315 IgA were fused with P3X63/Ag8 myeloma cells. Hybrid clones were screened for antibody production by a plate-binding radioimmunoassay in which MOPC 315 IgA was reacted with culture supernatants and 125I-protein A. One antibody-producing hybridoma clone (D10) was selected and injected i.p. into BALB/c mice. Ascitic fluid of tum or-bearing animals reacted specifically with MOPC 315 IgA and the reaction was inhibited by DNP- aminocaproic acid, indicating that the monoclonal antibody was directed against the hapten-binding site of MOPC 315 IgA. The monoclonal antiidiotypic antibody was of the complement (C)-binding IgG2a subclass and inhibited IgA production and growth of MOPC 315 cells in vitro in the presence of guinea pig C, as assessed by inhibition of formation of plaques and colonies by MOPC 315 cells in agar.

Animals↗

Selective action of colchicine on protein synthesis and release in a clonal line of rat glial cells.

The effect of colchicine on protein synthesis and secretion in stationary cultures of clonal rat glial cells C6 was examined. Colchicine inhibited the synthesis of the brain specific S100 protein in intact cells but not in a cell-free protein synthesizing system derived from these cells. There was no demonstrable effect of the drug on the synthesis of any of the several hundred proteins resolved by a two-dimensional electrophoretic analysis. However, colchicine specifically enhanced the secretion of several proteins of molecular weighs of 30,000 and of 200-300,000 into the medium. Two of the high molecular weight proteins were apparently membrane proteins whose release into the medium was stimulated by the drug.

Animals↗

Identification of rat brain polysomes synthesizing the brain specific enolase (14.3.2 protein), S100 protein and alpha and beta tubulin subunits.

Polysomes prepared from frozen rat brain powder were fractionated by centrifugation in a sucrose gradient. Individual fractions were used to program a reticulocyte lysate in a run-off reaction. The products of cell-free synthesis were assayed for the brain-specific enolase (14.3.2 protein) and S100 protein by immunoprecipitation with specific antisera and for tubulin by two-dimensional electrophoresis in polyacrylamide slab gels. The relative synthesis of these proteins by unfractionated free brain polysomes were 0.1 per cent, 0.05 per cent and 0.7 per cent respectively. After centrifugation in a sucrose gradient polysomes synthesizing S100 protein were separated from those synthesizing the other two markers. There was a threefold enrichment in the specific messenger RNA activity for each of the three proteins studied in their respective peak fractions of polysomes.

Animals↗