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E B Mushinski

Publications and source records attributed to E B Mushinski.

17 recordsLinked to original sources
PubMed2000

Clonal diversification of primary BALB/c plasmacytomas harboring T(12;15) chromosomal translocations.

DNA sequence analysis of PCR amplified Igh/c-myc junction fragments of T(12;15) chromosome translocations and immunohistochemical determination of immunoglobulin isotype production were employed to study the clonal diversification of neoplastic translocated plasma cells that resided in peritoneal inflammatory granulomas of BALB/c mice harboring primary plasmacytomas. The diversity of plasma cells was found to take two major forms when the fine structure of the T(12;15) translocation was used as the clonotypic marker. First, mosaics of clones containing translocations that were apparently unrelated to each other were detected in nine out of 17 (53%) mice. Second, subclones derived from common T(12;15)+ progenitors by either secondary deletions in translocation breakpoint regions or aberrant isotype switching near translocation breaksites were found in five of 17 (29.5%) mice. When Ig expression was utilized as the clonotypic marker, clonal mosaics were shown to occur in all mice. This was demonstrated by the finding that the prevalent IgA- or IgG-producing plasmacytoma clone was invariably accompanied by smaller clones of IgG- or IgA-expressing neoplastic plasma cells, respectively. These results provided new insights into the clonal diversification at the terminal stage of plasmacytomagenesis. In addition, they suggested that BALB/c plasmacytomas may be uniquely useful for studying clonal diversity during B cell oncogenesis, since clonal evolution can be evaluated in a pool of tumor and tumor precursor cells that is clearly defined by the T(12;15) chromosomal translocation and the production of monoclonal immunoglobulin.

Animals↗
PubMed1997

Immunoglobulin/Myc recombinations in murine Peyer's patch follicles.

Immunoglobulin heavy chain (Igh)/Myc recombinations are a hallmark of pristane-induced mouse plasmacytomas but are also frequently found in non-tumorous tissues. Here we describe for the first time a PCR-based technique for detecting fusions between Igh mu or Igh alpha and Myc in situ. Igh/Myc recombinations were found in transplanted and primary plasmacytomas. In addition, the gut-associated lymphoid tissues of plasmacytoma-free BALB/c mice were investigated for the presence of Igh/Myc fusions. Igh/Myc rearrangements were detected in Peyer's patch follicles and in the intestinal lamina propria both in normal mice and in mice shortly after pristane treatment. The sequence analysis showed that i) three to five different Igh/Myc hybrid sequences were present in individual follicles, ii) Igh/Myc recombinations can be subjected to additional switch recombinations as shown by related sequences in neighboring cells, and iii) cells harboring these rearrangements migrate into the adjacent lamina propria. The results indicate that Peyer's patches are a hyper-recombinogenic tissue. Myc recombination-positive cells are present in at least 100-fold more frequently than expected if recombinations were random, which suggests that this kind of trans-chromosomal rearrangement may be targeted.

Animals↗
PubMed1996

Cytotoxicity and membrane damage in vitro by inclusion complexes between gamma-cyclodextrin and siloxanes.

Inclusion complexes of gamma-cyclodextrin and octamethylcyclotetrasiloxane (D4), decamethyltetrasiloxane (M10TS), and 1,3,5,7-tetramethyltetravinylcyclotetra - siloxane (TMTV-D4) were prepared to compare the cytotoxic effects of siloxanes in vitro. In these preparations, the hydrophobic siloxanes are surrounded by a hydrophilic shell of eight circularly linked D-glucose molecules (gamma-cyclodextrin), and upon contact with plasma membranes the siloxane molecule can intercalate into the lipid bilayer of the cell membrane. XRPC24, 2-11 plasmacytoma, CH12.LX lymphoma and P388D1 macrophage-like cells were used as indicator cells in toxicity assays. Using an MTT tetrazolium reduction to formazan test, a colorimetric method to determine the number of viable cells, the 50% minimal lethal doses (CD50) for the siloxane compounds were found to range from 30 to 50 microM. Sublethal doses (e.g., 15 microM and lower) resulted in the loss of lactate dehydrogenase (LDH) and glutathione (GSH) from the cytosolic compartment of the target cells and thus indicated cytotoxicity. Treatment of macrophages with siloxanes resulted in a higher production of interleukin-6 (IL-6) than was exhibited by untreated macrophages. The B9 cell bioassay of these treated cells showed as much as a 10 fold higher production (500 U/ml) of IL-6 than did the untreated cells. The degree of increase was dependent on the compound and concentration used. The results of this study show that low molecular weight siloxanes produce lethal effects on B-lymphocyte derived target cells in vitro and permeabilize the plasma membranes at lower sublethal concentrations.

Animals↗
PubMed1994

Identification of two genes on chromosome 4 that determine resistance to plasmacytoma induction in mice.

BALB/cAn mice are highly susceptible to the induction of plasmacytomas (PCTs) by the i.p. injection of paraffin oils, whereas DBA/2 mice are solidly resistant. To search for genes that control the dominant resistant phenotype of DBA/2, BALB/c.DBA/2 (C.D2) congenic strains were constructed, and the susceptibility and resistance to PCT development were determined. PCT formation takes place over an extended period of 365 days but begins morphologically in focal proliferations of atypical plasma cells (foci) in the reactive oil granuloma that forms on mesenteric surfaces. Cells from some of these foci spread to other locations in oil granuloma tissue, forming new foci. Mice that develop six or more foci appear to be progressing towards eventual overgrowth and replacement of all peritoneal tissues with PCT cells. From Days 100 to 250, between 28 and 56% of PCT-susceptible BALB/cAn mice had 6 or more foci, whereas less than 5% of resistant DBA/2, BALB/c x DBA/2 F1 (hereafter called CD2F1), C57BL/6, and BALB/cJ mice had 6 or more foci. Four CD2 congenic strains carrying D2 alleles of genes on chromosomes other than chromosome 4 were highly susceptible. Between 0 and 20% of the mice in C.D2-Chr 4 congenic strains C.D2-MIA, C.D2-TF3, C.D2-Fv-1n/n, C.D2-Pnd7, C.D2-Lgm-1A, C.D2-Lgm-1B, C.D2-Lgm-1C, and C.D2-Lgm-1H developed 6 or more foci from 125 to 260 days, indicating resistance. The segments of DBA/2 chromosome 4 chromatin in C.D2-Fv-1n/n and C.D2-Pnd7 were discontinuous with those in C.D2-TF3, C.D2-Lgm-1A, C.D2-Lgm-1B, C.D2-Lgm-1C, and C.D2-Lgm-1H, indicating there are at least two genes (Pctr1 and Pctr2) in the distal half of this chromosome that confer resistance. Pctr1 is located between Ifa and D4Rck41, and Pctr2 is between Tnfr-1 and Pkcz. Each locus acting alone distinctly conferred a partial resistant phenotype. Pctr1 and Pctr2 did not appear to prevent the formation of clonal foci but did appear to limit the ability of the plasma cells in foci to acquire greater autonomy; thus, these genes affect tumor progression.

Animals↗
PubMed1987

Avian v-myc replaces chromosomal translocation in murine plasmacytomagenesis.

Deregulation of c-myc expression in association with chromosomal translocations occurs in over 95% of murine plasmacytomas, rat immunocytomas, and human Burkitt lymphomas. Infection with a murine retrovirus (J-3) containing an avian v-myc rapidly induced plasmacytomas in pristane-primed BALB/cAn mice. Only 17% of the induced plasmacytomas that were karyotyped showed the characteristic chromosomal translocations involving the c-myc locus. Instead, all of the translocation-negative tumors demonstrated characteristic J-3 virus integration sites that were actively transcribed. Thus, the high levels of v-myc expression have replaced the requirement for chromosomal translocation in plasmacytomagenesis and accelerated the process of transformation.

Animals↗
PubMed1977

The formation of active hybrid immunoglobulins from the heavy and light chains of beta(1, 6) D-galactan binding murine myeloma IgA's S10 and J539.

Murine myeloma immunoglobulin (IgA, K) J539, which shows enhanced tryptophanyl fluorescence on ligand binding, and S10, which shows reverse-sign changes in tryptophanyl fluorescence on ligand binding (RLIF, see below), have been reduced, alkylated, and dissociated into their light (L) and heavy (H) chains. Two hybrid recombinants, H10L539 and H539L10, have been prepared and the 7S material has been isolated by chromatography. The binding behavior of these recombinants was studied with a number of ligands. Both recombinants showed activity with beta(1 leads to 6) linked galactose ligands comparable to the native immunoglobulins. The ligand-induced fluorescence changes of the recombinants paralleled those of the heavy chain donor. For the recombinant H10L539, two different galactose-ligands caused fluorescence changes in opposite directions. It was quantitatively shown that binding of these ligands, nevertheless, took place in the same combining region. The idiotype of each recombinant resembled that of the heavy chain donor.

Animals↗
PubMed1977

Idiotypes on galactan binding myeloma proteins and anti-galactan antibodies in mice.

Antibodies with specificity for beta1,6 linked D-galactoses were induced in mice by immunization with gum ghatti. Idiotypic antisera were prepared in rabbits and mice by immunization with 8 BALB/c IgA(k), beta1,6D-galactan binding myeloma proteins (beta6GALBMP). Two kinds of idiotypic sera were obtained: cross-specific sera that reacted with two or more beta6GALBMP but not other BALB/c myeloma proteins, and individual idiotypic sera that reacted with only the beta6GALBMP used in the immunization. Antibodies with specificity for beta1,6 linked D-galactans shared cross-specific idiotypes with beta6GALBMP. Only one of seven individual idiotypes associated with beta6GALBMP was found on galactan antibodies. Since all beta6GALBMP thus far have the same Vk and VH isotope composition the results indicate an extensive heterogeneity among galactan-binding immunoglobulins in BALB/c mice. It is speculated that some of this diversity may arise from somatic rather than germ line gene mutations.

Animals↗
PubMed1976

Subunit interactions in mouse myeloma proteins with anti-galactan activity.

The interactions among the subunits of a unique set of mouse myeloma proteins having specificity for beta-D-(1,6) galactans has been studied by making homologous and heterologous recombinants of heavy and light chains. The recombinations were carried out by mixing together the desired heavy and light chains that had been separated on a Sephadex G-100 column in urea-acetic acid and renaturing the chains at near neutral pH. One homologous and six heterologous recombinants have been prepared. All the recombinants prepared possessed a four-chain native-like structure. The ligand binding activity and idiotypic specificity of the homologous recombinant were essentially indistinguishable from those of the original native protein. All the heterologous heavy-light chain combinations also led to the regeneration of functional binding sites. The affinity of the heterologous recombinants towards various galactose ligands was comparable to those of the native molecules. Furthermore, the ligand binding affinity of the recombinants was almost invariably closer to the Ka of the original protein that had a higher affinity. Idiotypic specificity of the heterologous recombinants paralleled that of the original protein that had contributed the heavy chain.

Animals↗
PubMed1975

Multiple individual and cross-specific indiotypes on 13 levan-binding myeloma proteins of BALB/c mice.

13 leven-binding myeloma proteins (LBMP) of BALB/c origin were classified into two groups with different binding specificities; one group of 11 proteins bound beta2 leads to 1 fructosans, a second group of two proteins bound fructosans probably of beta2 leads to 6 linkage. Anti-idiotypic sera prepared to 10 of the proteins in the appropriate strains of mice identified numerous idiotypic determinants. Each protein used for immunization had its own unique individual idiotypic specificities (IdI) and in addition most of the proteins carried two-nine cross-specific or shared idiotypes (IdX) that were found only among LBMP, and not found in 106 non-LBMP. Most of the IdX determinants and only four of the IdI determinants of the beta2 leads to 1 fructosan binding group were located in the antigen-binding site. The multiplicity of antigenic differences in this functionally related group of immunoglobulins reveals an unexpected degree of heterogeneity in V-regions that appears to be unrelated to binding.

Animals↗
PubMed1974

Genetics of a new IgVH (T15 idiotype) marker in the mouse regulating natural antibody to phosphorylcholine.

The idiotype present on the Fab of a phosphorylcholine-binding IgA myeloma protein TEPC 15 (T15) of BALB/c origin was found in normal serum of BALB/c mice. Molecules carrying the T15 idiotype in normal serum could be adsorbed with Sepharose phosphorylcholine beads and R36A pneumococci. The T15 idiotype is absent in germ-free BALB/c but appears when the mice are conventionalized. A survey of normal sera of inbred strains for the T15 idiotype showed it to be present in BALB/c, 129, C57L, C58, and ST and absent or in low levels in CBA, C3H, C57BL/6, C57BL/Ka, C57BL/10, SJL, B10.D2, DBA/2, RIII, A, AL, AKR, NZB, and NH inbred strains of mice. The T15 idiotype is associated with some but not all strains carrying the IgC(H) allotypes found in BALB/c. Linkage of genes controlling the T15 idiotype in normal serum to the IgC(H) locus of BALB/c was demonstrated in F(2) progeny of a BALB/c and C57BL cross, Bailey's recombinant inbred strains, C x BD, C x BE, C x BG, C x BH, C x BI, C x BJ, C x BK, and CB20 congenic strains. Among these strains, only those possessing the IgC(H) locus of BALB/c including the F(2) progeny consisting of BALB/c homozygotes and BALB/c/C57BL heterozygotes and C x BG and C x BJ recombinants showed the T15 idiotype.

Animals↗
PubMed1973

Six BALB-c IgA myeloma proteins that bind beta-(1-6)-D-galactan. Partial amino acid sequences and idiotypes.

Six IgA myeloma proteins of BALB/c origin which bind antigens containing beta-(1 --> 6)-D-galactan side chains have been isolated by affinity chromatography on galactoside-BSA-Sepharose columns. Partial amino acid sequences of of the light chains to residue Cys23 and the heavy chains to reside 30 were determined on the automated sequencer. No differences were found among the six V(K) sequences. Among some 50 partial V(K) sequences that have thus far been determined these six chains are the only ones thus far identified in this subgroup; at least 25 V(K) subgroups in the mouse have been identified so far. The heavy chain partial sequences were also very closely related but two differences were found. One protein differed from the other five by having isoleucine instead of leucine at position 5, a second protein differed from the others by having an unidentified amino acid at position 19. Using the highly sensitive inhibition of hemagglutination method it was found that each of the proteins possessed a unique inidividual antigenic determinant.

Amino Acid Sequence↗
PubMed1973

Evidence for the linkage of the IGC H locus to a gene controlling the idiotypic specificity of anti-p-azophenylarsonate antibodies in strain A mice.

Anti-p-azophenylarsonate (anti-Ar) antibodies elicited in all strain A/J mice tested share one or more idiotypic specificities. These specificities are also found in the anti-Ar antibodies of mice of the closely related strain, AL/N, but not in those of BALB/c mice. Anti-Ar antibodies were elicited in congenic mice in which the IgC(H) locus of AL/N mice, which controls allotypic markers in the constant regions of heavy chains, had been introgressively backcrossed for nine generations onto a BALB/c background; the mice were then rendered homozygous for the AL/N allotypic determinant. On the average, these antibodies were quantitatively equivalent, with respect to content of the cross-reactive idiotype, to those of AL/N mice. This indicates that the gene controlling the idiotype is closely linked to the IgC(H) locus. Since idiotype must be a function of V region sequences, the results suggest close linkage of V(H) and C(H) genes. The cross-reactive idiotype was found in nearly all F(1) mice (C57/BL x A/J or BALB/c x A/J) tested.

Animals↗