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Biomedical subjects

R G Krueger

Publications and source records attributed to R G Krueger.

At least 19 recordsLinked to original sources
PubMed1979

Effect of plant lectins on murine myeloma cells.

The mitogenic response (determined by uptake of [3H]-thymidine) of two different BALB/c myeloma lines, normal BALB/c spleen cells and spleen cells from tumour-bearing mice in primary culture to PHA, Con A, PWM and Robinia pseudoaccacia (RPA) extract was determined by measuring the uptake of [3H]-thymidine over 96 h. The pattern of the response of tumour and tumour-spleen cells to the 4 different lectins was similar, and different from that of normal spleen cells. The unstimulated cultures of tumour and tumour-spleen cells displayed an initial increased uptake of [3H]-thymidine, whereas stimulated cultures displayed a low initial uptake of label. After an initial phase of inhibition, ADJ-PC5 myeloma cells were stimulated by PHA and PWM to a greater extent than were normal spleen cells. On the other hand, normal spleen cells gave a markedly better response to Con A and RPA. The mitogenic response of tumour-spleen cells to all 4 lectins was intermediate between those observed for tumour and normal spleen cells; they responded better to Con A and RPA than did tumour cells but were not as responsive as spleen cells, whereas the converse was true for their response to PWM and PHA. In agreement with other reports, the data suggest that the responsiveness of tumour-spleen cells was due to the presence of tumour cells in this tissue. These results indicate that there is no definite evidence of an impaired lectin-responsiveness in lymphoid cells of mice bearing a myeloma.

Animals↗
PubMed1978

Circulating lymphocytes and the spread of myeloma. Review of the evidence.

Patients with myeloma harbour circulating lymphocytes which bear the idiotypic determinants (SIg-id+ cells) of their own myeloma protein. Circulating white cells with abnormal karyotypes have been found in other patients with this disease. SIg-id+ lymphocytes have also been identified in the peripheral blood of myeloma-tumour-bearing mice. Murine myelomas have been propagated in vivo from circulating mononuclear cells that possessed myeloma-tumour-associated antigens. This and other evidence reviewed here points strongly to the involvement of circulating lymphocyte-like stem cells in the spread of human myeloma.

Animals↗
PubMed1978

Perineural angiogenesis in mice bearing subcutaneous tumours.

Cells of myeloma or fibrosarcoma were inoculated s.c. into BALB/c mice. Intact skins and tissue sections from animals killed at periodic intervals after inoculation of tumor cells were examined macroscopically and microscopically. The development of new blood vessels, probably involved in vascularization of the tumor, was observed around the nerves adjacent to the deposit of tumour cells. This occurred 5 days after inoculation of cells and before the tumour had a mean diameter of less than 1 mm. Lesser degrees of "perineural angiogenesis" were noted after s.c. inoculation of mineral oil, Freund's complete adjuvant or implantation of intact spleen, but none was observed with killed tumour cells.

Animals↗
PubMed1977

Circulating tumor cells in murine myeloma.

BALB/c mice bearing subcutaneous ADJ-PC5 myelomas had hematologic findings suggestive of a preleukemic syndrome: thrombocytopenia, anemia, leukocytosis, and megakaryocytic hyperplasia. Six BALB/c myelomas were successfully transplanted sc by fragments or cell suspensions of spleens from mice bearing a subcutaneous tumor, though typical myeloma cells were difficult to visualize by light microscopy in these spleens. The fidelity of transmission of the ADJ-PC5 myeloma by this procedure was shown by the retention of idiotypic specificity of the immunoglobulin produced by the tumor in a radioimmunoassay. The tumorigenic cell that homed to the spleen was apparent as early as 8 days after sc transplantation of the myeloma. The spleens of tumor-bearing mice, however, could destroy or suppress the expansion or growth of a limited number of cells that had migrated to the spleens. Tumorigenic cells present in the peripheral circulation constituted 2-3% of the leukocytes. These cells, however, had reduced levels of the murine myeloma viral and cell-associated antigens, were difficult to detect by an indirect immunofluorescence assay, and did not rapidly divide in this environment, as indicated by the very low number of cells detected by autoradiography.

Animals↗
PubMed1976

Antibody differentiation: apparent sequence identity between variable regions shared by IgA and IgG immunoglobulins.

We have analyzed a pair of human myeloma immunoglobulins (biclonal proteins) of the IgG and IgA classes from a single patient, GR. The light chains are identical in amino-acid sequence over 40 residues at their NH2-terminus, hwereas the heavy chains are identical throughout 45 residues of their NH2-terminus. Additional chemical and serological studies suggest the light chains and variable regions of the heavy chains (VH) are very similar, if not identical. The implications of these and of other published studies are discussed with regard to (i) the association of one VH region with multiple constant regions of the heavy chain (CH regions), (ii) two alternative types of V-C joining mechanisms, (iii) the differentiation of antibody-producing cells, and (iv) three categories of biclonal immunoglobulins.

Amino Acid Sequence↗
PubMed1976

Tumor-associated antigens in human myeloma.

Antiserum was generated in rabbits to the RPMI 8226 tissue culture line of human myeloma cells, and its reactions with fixed smears of bone marrow aspirates from patients with multiple myeloma, macroglobulinemia, benign monoclonal gammopathy (BMG), leukemia, and nonneoplastic plasmacyosis was assessed by indirect immunofluorescence. After absorption with preparations of bone marrow from normal individuals, the antiserum reacted to a significantly higher titer with a specific subpopulation of plasma cells in smears from 81% of patients having multiple myeloma and 50% of patients having BMG than with cells in smears of bone marrow aspirates from normal individuals or patients having leukemia or nonneoplastic plasmacytosis, or than with cells in smears of peripheral blood from patients having Hodgkin's and non-Hodgkin's lymphoma. Absorption of the antiserum with RPMI 8226 cells or with a bone marrow preparation from a patient with multiple myeloma but not the Jijoye line of Burkitt's lymphoma reduced reactivity for cells in myeloma bone marrow. The antiserum reacted at a lower titer with the Jijoye and EB-3 lines of Burkitt's lymphoma, the RPMI 4098 cell line of normal human lymphocytes, and culture lines of human melanoma and osteogenic sarcoma than with the RPMI 8226 cells or bone marrow from certain patients having multiple myeloma. Approximately 50% of the cells reactive with antiserum to RPMI 8226 cells in the bone marrow of patients with multiple myeloma were not producing immunoglobulin, as assessed by double immunofluorescence assay. The data suggested that a subpopulation of plasma cells in the bone marrow of patients with multiple myeloma possesses a tumor-associated antigen.

Absorption↗
PubMed1976

Intracisternal A particles from FLOPC-1 BALB/c myeloma: presence of high-molecular-weight RNA and RNA-dependent DNA polymerase.

Intracisternal A particles from the FLOPC-1 line of BALB/c myeloma have been shown to contain high-molecular-weight RNA (60 to 70S) that is sensitive to RNase, alkali degradation, and heat but resistant to Pronase treatment. The intracisternal A-particle RNA contains tract of poly (A) approximately 180 nucleotides long. As shown in a reconstitution experiment, by antigenic analysis of A-particle preparation and the SC cytopathogenicity assay, the 70S RNA was not due to contamination by type C virus particles. The FLOPC-1 intracisternal A particles also possess an endogenous RNA-dependent DNA polymerase. The enzyme required Mn2+ or Mg2+, dithiothreitol, detergent, and four deoxyribonucleoside triphosphates for maximum activity. Enzymatic activity was maximally stimuated by poly (rC)-oligo (dG)12-18 and less with poly (rG)-oligo (dC)10 or poly (rA)-oligo (dT)12-18 as compare with synthetic DNA/DNA duplex templates such as poly (dA)-oligo (dT)12-18. The enzyme can utilize the A-particle endogenous RNA as template as shown by analysis of the early and late DNA products of the endogenous reaction by CsSO4 isopycnic gradient centrifuation and hybridization of purified 70S or 35S A-particle RNA with the purified complementary DNA product. Approximately 50% of the A-particle complementary DNA also hybridized with oncornavirus RNA.

Animals↗
PubMed1976

Development of monoclonal IgA and an apparent IgG in a patient with macroglobulinemia: sharing of individually specific antigenic determinants among IgM, IgA, and IgG.

Patient CM, who initially was diagnosed as having macroglobulinemia (IgM, kappa) was subsequently found to develop a monoclonal IgA(kappa) protein. Rabbit antisera directed against the patient's IgAm and IgM were rendered specific for individual antigenic (ind) determinants. The anti-IgAm and IgM ind sera reacted with both 131I labeled monoclonal proteins in a double antibody radioimmunoassay (RIA). In addition, both monoclonal immunoglobulins inhibited the reaction between labeled immunoglobulin and both ind antisera, and statistical analysis of the data suggested that the shared ind determinants were identical. The IgG fraction of patient CM's serum also contained a component which competed with both monoclonal IgA (CM) and IgM (CM) in the RIA specific for ind determinants. Analysis of serum samples taken over a 2-year period revealed that, in addition to IgM, both the IgA and IgG components possessing the shared ind determinant(s) were present in low concentrations in the earliest sample, although not detected by conventional techniques. The monoclonal IgA and the IgG component were found to increase in concentration over this time interval with a concomitant decrease in IgM. The regulation of immunoglobulin expression with respect to the proposed models of gene organization in antibody-producing cells was discussed.

Antibody-Producing Cells↗
PubMed1975

Studies on IgA and IgA monoclonal proteins derived from a single patient. Evidence for identical light chains and variable regions of the heavy chain.

Two immunoglobulins, IgA(K) and IgG(K), were isolated from the serum of a single patient with two monoclonal components (biclonal proteins). After chain separation, the light chains from each molecule were found to be identical by the following criteria: electrophoretic mobilities under various pH and dissociating conditions, amino acid compositon, fingerprint analysis of tryptic peptides and of 14C-succinylated chymotryptic peptides, and amino acid sequence of the N-terminal 40 residues. The heavy chains were indistinguishable for the N-terminal 45 amino acid residues. These data are consistent with the hypothesis that a single heavy chain variable (VH) region may be associated with two different heavy chain constant (CH) genes.

Amino Acid Sequence↗