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J G Pumphrey

Publications and source records attributed to J G Pumphrey.

14 recordsLinked to original sources
PubMed1998

Disseminated growth of murine plasmacytoma: similarities to multiple myeloma.

Murine plasma cell tumors share a number of common features with human multiple myeloma, suggesting their possible use as a model for this disease. However, one major difference between the two is the peritoneal localization of murine tumors as opposed to bone marrow residence of malignant plasma cells in early stages of multiple myeloma. We have thus examined the ability of murine plasmacytoma to produce disseminated growth similar to that seen in myeloma or other lymphoid neoplasias. Of four murine cell lines evaluated, all were demonstrated to effect highly metastatic disease involving multiple organs, although variation was observed between lines. A temporal analysis was accordingly performed with the S107 line to assess the pattern of cellular localization. Both light microscopy and PCR analysis revealed that engraftment of plasma cells occurs first in the bone marrow, followed by dissemination to other sites including the spleen, lung, and liver. Cells passaged in vivo through the bone marrow display an entirely different metastatic pattern with no homing preference to bone marrow or any other organ, suggesting the occurrence of a phenotypic change. Microscopic osteolytic lesions were observed adjacent to plasma cell tumor masses in the bone marrow, indicating early stages of bone disease. These findings demonstrate previously unrecognized similarities between the murine and human diseases and suggest the use of this in vivo model for experimental approaches to the treatment of human disease.

Animals↗
PubMed1997

Characterization of C57BL/6 plasmacytomas lacking a c-myc translocation.

BALB/c peritoneal plasmacytomas induced by a variety of agents are invariably associated with a c-myc translocation. In contrast, naturally arising bone marrow plasma cell tumors in C57BL/KaLwRij mice lack this translocation. This difference has led to the suggestion that these are 2 fundamentally different plasma cell diseases. Herein, we have analyzed 2 rare C57BL/6 peritoneal plasmacytomas in terms of characteristics associated with the bone marrow-derived lines. Like the bone marrow lines, these peritoneal plasmacytomas do not exhibit c-myc translocations, indicating that c-myc translocation is not an obligatory event in the development of all murine extramedullary plasmacytomas. However, myc is dysregulated at the mRNA level, indicating that myc overexpression may be fundamental to most plasma cell diseases but that dysregulation can occur by alternative mechanisms possibly reflecting different genetic backgrounds.

Animals↗
PubMed1993

Susceptibility and resistance to J3V1 retrovirus-induced murine plasmacytomagenesis in reconstituted severe combined immunodeficient mice.

To date much is known about the genetics of susceptibility and resistance to plasmacytoma induction in mice, however little is known about the cellular aspects of these phenotypes. The complexity of plasmacytomagenesis allows for susceptibility and resistance to reflect differences in B cells, T cells, accessory cells and/or stromal elements contributing to the disease process. Alternatively, these phenotypes may result from differential abilities to affect events critical to plasmacytomagenesis, such as myc deregulation. To address these possibilities, the v-myc-raf-containing retrovirus, J3V1, was used to induce plasmacytomas (PCTs) in severe combined immunodeficient (SCID) mice reconstituted with susceptible (Balb/c) and/or resistant (DBA/2) cells. The results demonstrate that Balb/c bone marrow (BM)-reconstituted SCID mice yielded PCTs of donor origin, while DBA/2 BM-reconstituted mice did not. Mice reconstituted with both DBA/2 BM and Balb/c peripheral lymphocytes, as well as those reconstituted with Balb/c peripheral lymphocytes alone, also yielded only Balb/c PCTs. These results indicate that: (1) a microenvironment supportive of plasmacytomagenesis is insufficient to allow PCT development among resistant cells; (2) DBA/2 BM-derived cells do not suppress plasmacytomagenesis by target cell elimination or microenvironment destruction; (3) resistance is not solely attributable to the inability of DBA/2 B cells to deregulate myc; and (4) potential PCT targets reside in a number of lymphoid tissues. Taken together, these results demonstrate that a major aspect of resistance/susceptibility to plasmacytomagenesis is dictated by the genotype of the target B cell.

Animals↗
PubMed1987

Purification and NH2-terminal sequence of a plasmacytoma growth factor derived from the murine macrophage cell line P388D1.

Plasmacytoma growth factor (PCT-GF), a putative macrophage-derived lymphokine essential for the in vitro viability and proliferation of early generation plasmacytomas, was purified from conditioned medium of the murine macrophage cell line P388D1. The purification of PCT-GF was accomplished by a batch concentration on trimethylsilyl-controlled pore glass beads, followed by: gel filtration chromatography; hydrophobic interaction HPLC; and reverse-phase HPLC. SDS-PAGE analysis of the purified PCT-GF revealed a single band of Mr 23,000. The amino terminal sequence of PCT-GF was established as NH2-Pro-Thr-Ser-Gln-Val-Arg-Arg-Gly-Asp-Phe-Thr-Glu-Asp-Thr-Thr-Pro-Asn- Arg-Pro-Val-Tyr-Thr. No significant homology was found between this sequence and proteins in the National Biomedical Research Foundation database, suggesting that PCT-GF is a new lymphokine unrelated to previously described growth and differentiation factors.

Amino Acid Sequence↗
PubMed1987

Identification of cysteine 656 as the amino acid of hepatoma tissue culture cell glucocorticoid receptors that is covalently labeled by dexamethasone 21-mesylate.

Recent results using proteases suggest that dexamethasone 21-mesylate (Dex-Mes) labeling of the rat hepatoma tissue culture (HTC) cell glucocorticoid receptor occurs at one or a few closely grouped cysteine residues (Simons, S.S., Jr. (1987) J. Biol. Chem. 262, 9669-9675). In this study, a more direct approach was used both to establish that only one cysteine is labeled by [3H]Dex-Mes and to identify the amino acid sequence containing this labeled cysteine. Various analytical procedures did not provide the purification of the extremely hydrophobic Staphylococcus aureus V8 protease digestion fragment that is required for unique amino acid sequencing data. Therefore, Edman degradation was performed on the limit protease digest mixtures which appeared to contain only one 3H-labeled peptide. These degradation experiments revealed the number of amino acid residues between the NH2 terminus of each peptide and the [3H]Dex-Mes-labeled cysteine. A comparison of these amino acid spacings with the published amino acid sequence of the HTC cell glucocorticoid receptor (Miesfeld, R., Rusconi, S., Godowski, P. J., Maler, B. A., Okret, S., Wikstom, A-C., Gustafsson, J-A., and Yamamoto, K. R. (1986) Cell 46, 389-399) indicated that the one cysteine labeled by [3H]Dex-Mes is Cys-656. Further analysis of the receptor sequence for the presence of the observed grouping of proteolytic cleavage sites, but without any preconditions as to which amino acid was labeled, gave Asp-122 and Cys-656 as the only two possibilities. Potential labeling of Asp-122 could be eliminated on the basis of immunological and genetic evidence. We, therefore, conclude that the single Dex-Mes-labeled site of the HTC cell glucocorticoid receptor has been identified as Cys-656. Since several lines of evidence indicate that [3H]Dex-Mes labeling of the receptor occurs in the steroid binding site, Cys-656 is the first amino acid which can be directly associated with a particular property of the glucocorticoid receptor.

Affinity Labels↗
PubMed1986

Functional antibody lacking a variable-region disulfide bridge.

In 1981, Auffray et al. [Auffray, C., Sikorav, J. L., Ollo, R. & Rougeon, F. (1981) Ann. Immunol. (Inst. Pasteur) 132D, 77-88] reported a partial cDNA sequence of the heavy chain from the ABPC48 plasmacytoma whose protein product had previously been shown to bind bacterial and grass levan. In the cDNA sequence the second half-cystine of the heretofore invariant disulfide bridge had been replaced by a tyrosine. Since the presence of invariant variable-region disulfide bridges has been considered a basic structural feature of the antibody molecule necessary for proper folding and function, we have analyzed the heavy chain protein produced by ABPC48. Our results indicate that heavy chains from ABPC48 quantitatively express tyrosine in place of the normally occurring second half-cystine in the variable region. Furthermore, this antibody population is capable of both binding antigen and subsequent precipitation. Thus, the presence of a disulfide bridge in the heavy-chain variable region does not appear necessary for proper function of this antibody and may not be obligatory for antibody function in general, as has been assumed previously.

Antibodies↗
PubMed1985

A nephelometry system for the Abbott TDx analyzer.

A self-contained light-scattering accessory carousel has been developed for the Abbott TDx fluorescence polarization analyzer, extending the instrument's capabilities to nephelometric methods of analysis, including assays for specific proteins by immunoprecipitation: IgG, IgA, IgM, and transferrin. The scattered light from a green-light-emitting diode (peak wavelength 565 nm) is measured at an angle of 37.5 degrees by the existing optical detection system of the TDx analyzer without modification of the instrument. Measurements are made at quasi-equilibrium, with sample blank correction. No sample pretreatment is required, and antigen-excess is checked automatically. CVs range from 3 to 6% (within-run) and 7 to 9%. (total). Calibration curves may be stored for at least two weeks. A nephelometric method for monitoring chromogenic reactions in the green wavelength region is also described. This method--Scattered Energy Attenuation (SEA)--has been used in preliminary experiments to measure calcium, total protein, iron, and bilirubin.

Autoanalysis↗
PubMed1976

Murine plasma cells secreting more than one class of immunoglobulin heavy chain. I. Frequency of two or more M-components in ascitic fluids from 788 primary plasmacytomas.

Primary ascites from 778 consecutive plasmacytomas of BALB/c and other mouse strains were tested by immunoelectrophoresis for the presence of paraproteins belonging to different immunoglobulin classes. gammaA was produced by 338 tumors: gamma Gs (gamma 1, gamma 2a, gamma 2b, or gamma 3) by 163 tumors; and gamma M by seven tumors. Free kappa- or lambda-typed light chains were produced by 14 tumors, and no detectable paraprotein was produced by 202 tumors. Two or more paraproteins were detected in the primary ascites of 54 plasmacytomas. Evidence suggests that in most cases, the multiple paraproteins are produced by simultaneously occurring, independent plasma cell tumors. However, two tumors, SAMM 368 and TEPC 609, produced two paraproteins for over 30 generations in transplantation. This finding implies that single clones of plasma cells have the capacity to produce more than one class of immunoglobulin.

Animals↗
PubMed1975

Genetics of susceptibility to plasmacytoma induction. I. BALB/cAnN (C), C57BL/6N (B6), C57BL/Ka (BK), (C times B6)F1, (C times BK)F1, and C times B recombinant-inbred strains.

Plasmacytomas were found in 58% of 373 BALB/cAnN (C) mice given three 0.5-ml doses of mineral oil (Bayol F or light mineral oil) or 2,6,10,14-tetramethylpentadecane (pristane) ip. The incidence of plasmacytomas in C57BL/6N (B6), C57BL/Ka (BK), (C times B6)F1 and (C times BK)F1 was 6.4, 0, 11.5, and 16.5%, respectively. The plasmacytomas occurred in old B6 mice, in contrast to their early appearance in strain C mice. The incidence of plasmacytomas in mineral oil-treated or pristane-treated C times B recombinant-inbred (Rl) strain mice was 28.3% in C times BD, 17.5% IN C times BE, 36.5% IN C times BG, 0% in C times BH, 2.9% in C times Bl, 48% in C times BJ, and 4.3% in C times BK. C times BD, C times BG, and C times BJ strains were considered susceptible to plascytoma induction by mineral oil or pristane; C times BE had a low susceptibility, and C times BH, C times Bl, and C times BK were resistant. The results suggested that there were only a few gene difference between C and B6 or BK that determined susceptibility or resistance to plasmacytoma induction, and that B6 and BK have at least one dominant resistance gene. The distribution pattern of susceptibility and resistance in the C times B Rl strains suggested the presence of a resistance gene on chromosome 9, linkage group II.

Age Factors↗