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D E Mosier

Publications and source records attributed to D E Mosier.

At least 19 recordsLinked to original sources

Epstein-Barr virus-induced human B-cell lymphomas in SCID mice reconstituted with human peripheral blood leukocytes.

Epstein-Barr virus (EBV) infection is associated with immunoblastic B-cell lymphomas in immunosuppressed or human immunodeficiency virus-infected individuals and in SCID mice reconstituted with human peripheral blood leukocytes (hu-PBL-SCID) from EBV-seropositive donors. The risk of tumors appearing in the hu-PBL-SCID mice differs among EBV-seropositive donors. Four different outcomes have been noted: (a) no tumors appear (no incidence donors); (b) tumors appear in a fraction of hu-PBL-SCID mice with a 10-20 week latent period (low- and intermediate-incidence donors); or (c) tumors appear in all hu-PBL-SCID mice within 6-10 weeks (high-incidence donors). The latter category of rapidly appearing tumor invariably involved activation of EBV replication, whereas more slowly growing tumors rarely activated EBV. The results indicate that prospective screening of high-risk individuals in the hu-PBL-SCID model may predict the risk of EBV-associated lymphoma development.

Animals

Cytogenetic characterization of B-cell lymphomas from severe combined immunodeficiency disease mice given injections of lymphocytes from Epstein-Barr virus-positive donors.

We analyzed the karyotype of 27 B-cell lymphomas of human origin that developed in mice with severe combined immunodeficiency disease following the injection of peripheral blood leukocytes from Epstein-Barr virus-seropositive donors. Three tumors had clonal abnormalities detected with conventional techniques, 2 had trisomy 11, and 1 had a del(6)(q21q25). One other tumor had trisomy 11 detected with fluorescence in situ hybridization. Twelve tumors had a normal karyotype, 11 tumors had nonclonal abnormalities (which included trisomy 9 or 12 in 3 or 2 tumors, respectively), and one tumor had a karyotype of 92,XXXX(75%)/46,XX(25%) by conventional cytogenetic analysis. Trisomy for chromosomes, 9, 11, and 12 are recurring abnormalities that have been observed in lymphomas associated with an immunocompromised state. Clonal or nonclonal abnormalities were observed in 8 of 11 tumors derived from 3 donors whose peripheral lymphocytes induced a high incidence of tumors in mice with severe combined immunodeficiency disease compared with a clonal abnormality and 2 nonclonal abnormal cells in 2 of 5 tumors derived from 3 donors whose lymphocytes induced an intermediate to low incidence. These observations suggest an association between a higher incidence of karyotypically abnormal cells in lymphomas and the increased tumorigenic potential of the lymphocytes that induced these tumors.

Animals

Heterogeneity among Epstein-Barr virus-seropositive donors in the generation of immunoblastic B-cell lymphomas in SCID mice receiving human peripheral blood leukocyte grafts.

Epstein-Barr virus (EBV) is associated with B-cell malignancy in immunosuppressed humans and SCID mice receiving human peripheral blood leukocyte grafts (hu-PBL-SCID). We have further characterized the process of lymphoma development in hu-PBL-SCID mice. We report that EBV-seropositive donors differ markedly in the capacity of their PBL to give rise to immunoblastic lymphomas in SCID mice; some donors (high incidence) generated tumors rapidly in all hu-PBL-SCID mice, other donors (intermediate-low incidence) gave rise to sporadic tumors after a longer latent period (greater than 10 weeks), and some donors failed to produce tumors. B-cell lymphomas arising from high incidence donors were multiclonal in origin, and EBV replication was detected in all tumors. Tumors derived from intermediate-low incidence donors were monoclonal or oligoclonal and often had no evidence of viral replication. All tumors, regardless of the donor, resembled EBV-transformed lymphoblastoid cell lines in surface phenotype but differed from lymphoblastoid cell lines by having less Epstein-Barr nuclear antigen 2 and CD23 expression. The variable patterns of lymphomagenesis seen among different EBV-sero-positive donors may be explained by lower levels of specific immunity to EBV in high incidence donors, permitting activation of EBV replication and potential transformation of secondary B-cell targets. In addition, there may be differences in the transforming potential of EBV infecting different donors. The use of the hu-PBL-SCID model may help predict patients at high risk for posttransplant or acquired immunodeficiency syndrome-associated lymphomas.

Age Factors

CD4+CD8- thymocytes from neonatal mice induce IgM production in SCID mice.

Defective recombination of both the TCR and Ig genes results in the absence of mature lymphocytes in mice with the scid mutation. We have shown previously that the transfer of neonatal, but not adult, thymocytes results in high levels of Ig production in 100% of C.B-17-scid (SCID) mice, in contrast to the 10 to 25% of SCID mice spontaneously producing low levels of oligoclonal Ig. In this report we demonstrate that neonatal CD4+8- thymocytes were able to induce this response; the CD4+8+ and CD4-8+ subpopulations were totally inactive and CD4-8- T cells had only limited activity several weeks after transfer. The stimulation of IgM production in SCID mice was detectable by 1 wk posttransfer of CD4+8- thymocytes or splenic T cells, and could be achieved with as few as 300 cells. The ability of neonatal CD4+8- thymocytes to induce Ig diminished gradually to insignificant levels at 3 wk postbirth; this loss of function was not associated with differential survival of neonatal T cells. Neonatal CD4+8- thymocytes from C.B-17 and other H-2d strains rescued Ig production, whereas cells from H-2b, H-2a, and H-2k strains were much less effective. These results suggest that a CD4+8- subpopulation found in both neonatal thymus and peripheral lymphoid tissues is able to induce the expansion or differentiation of the small numbers of functional B lymphocytes in SCID mice, and that the inducing T cell disappears shortly after birth, perhaps during the acquisition of self-tolerance.

Age Factors

Transfer of human chronic lymphocytic leukemia to mice with severe combined immune deficiency.

B chronic lymphocytic leukemia (CLL) cells were transferred into mice with severe combined immunodeficiency (SCID). Leukemia cells injected into the peritoneal cavity of these animals may survive for at least 10 weeks in vivo. In contrast, leukemia cells do not survive for long periods when injected intravenously. Despite the longevity of CLL cells injected i.p., these cells apparently do not migrate to other lymphoid tissues. Eight to sixteen weeks after receiving CLL cells, SCID mice develop human IgG autoantibodies to human red blood cells and/or high serum levels of human Ig. Soon thereafter, these animals develop lethal human B-cell tumors. In contrast to the original CLL cells, these human B-cell tumors are CD5-negative, have genomic DNA of Epstein-Barr virus (EBV), express antigens associated with latent EBV infection and have distinctive Ig gene rearrangements by Southern. We conclude that bystander B cells may generate tumors in CLL-reconstituted SCID mice that emulate the EBV-associated lymphoproliferations noted in SCID mice reconstituted with normal human PBL.

Animals

Epstein-Barr virus nuclear protein 2 is a critical determinant for tumor growth in SCID mice and for transformation in vitro.

Injection of Epstein-Barr virus (EBV)-transformed human lymphoblastoid B cells into immunodeficient SCID mice results in the appearance of rapidly growing, fatal human B-cell tumors. To evaluate the role of EBV nuclear protein 2 (EBNA-2) in this process, we generated lymphoblastoid cell lines transformed by several EBV mutants which were identical except for deletions in the EBNA-2 gene (J. I. Cohen, F. Wang, and E. Kieff, J. Virol. 65:2545-2554, 1991). These cell lines were injected intraperitoneally into SCID mice, and the interval until tumor detection was determined. Cell lines transformed with EBV type 1 (strain W91) or with EBV type 2 (strain P3HR-1) with an inserted type 1 EBNA-2 gene grew at the same rapid rate, indicating the potential importance of EBNA-2 for tumor formation in vivo. Cell lines derived from three different EBV mutants with deletions in the amino half of EBNA-2 produced tumors more slowly than cell lines transformed by wild-type W91 virus. In contrast, a cell line transformed with an EBV mutant with a deletion in the carboxy terminus of EBNA-2 grew more rapidly than cell lines transformed by wild-type virus. EBV mutants with deletions in the amino half of EBNA-2 had had reduced transforming activity in vitro, while the carboxy-terminal EBNA-2 mutant had had transforming activity greater than or equal to that of the wild type. These data indicate that EBNA-2 plays a critical role both for B-cell tumor growth in SCID mice and for B-lymphocyte transformation in vitro.

Animals

EBV-induced human B cell lymphomas in hu-PBL-SCID mice.

Epstein-Barr virus (EBV) infection is associated with Burkitt's lymphoma (BL) in normal individuals and immunoblastic B cell lymphomas in immunosuppressed or HIV-infected individuals. SCID mice reconstituted with human peripheral blood leukocytes (hu-PBL-SCID) from EBV-seropositive donors also may develop spontaneous B cell lymphomas which histologically and phenotypically resemble post-transplant tumors, and are distinct from BL. These tumors always contain EBV DNA. We have noted three different reproducible outcomes depending upon the EBV-seropositive donor used for generation of hu-PBL-SCID mice: (i) no tumors appear; (ii) tumors appear in a fraction of hu-PBL-SCID mice with a 10-20 wk. latent period; or (iii) tumors appear in all hu-PBL-SCID mice within 6-10 wk. Southern blot analysis of late versus early tumors using a probe specific for the EBV terminal repeat sequences (BamNJ), which allows distinction between circular latent and linear replicating genomes, shows that late tumors do not involve active EBV replication but that early tumors do show replicating genomes. In addition, EBV genomes were monoclonal in late tumors but polyclonal in early tumors. These data suggest two mechanisms for EBV lymphomagenesis, slow outgrowth of rare latently-infected B cells, and more rapid transformation of uninfected bystander B cells by replicating virus. The latter process may be highly amenable to therapy in patients at risk for EBV-related lymphomas. In addition, prospective screening of EBV-seropositive transplant recipients in the hu-PBL-SCID model may predict the risk of post-transplant lymphoma development.

Animals

Break for SCIDs.

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Animals

Human immunodeficiency virus infection of human-PBL-SCID mice.

Severe combined immunodeficient (SCID) mice reconstituted with human peripheral blood leukocytes (hu-PBL-SCID mice) have inducible human immune function and may be useful as a small animal model for acquired immunodeficiency syndrome (AIDS) research. Hu-PBL-SCID mice infected with human immunodeficiency virus-1 (HIV-1) contained virus that was recoverable by culture from the peritoneal cavity, spleen, peripheral blood, and lymph nodes for up to 16 weeks after infection; viral sequences were also detected by in situ hybridization and by amplification with the polymerase chain reaction (PCR). Mice could be infected with multiple strains of HIV-1, including LAV-1/Bru, IIIB, MN, SF2, and SF13. HIV-1 infection affected the concentration of human immunoglobulin and the number of CD4+ T cells in the mice. These results support the use of the hu-PBL-SCID mouse for studies of the pathogenesis and treatment of AIDS.

Animals

Adoptive transfer of neonatal T lymphocytes rescues immunoglobulin production in mice with severe combined immune deficiency.

Mice with the autosomal recessive severe combined immune deficiency (scid) mutation lack mature lymphocytes because of defective joining of T cell receptor and immunoglobulin (Ig) gene segments. Penetrance of this mutation is incomplete since 10-25% of SCID mice produce some T or B lymphocytes. This "leaky" phenotype could be due to a reversion of the mutation in some mice or to a constant, low frequency of functional lymphocytes generated in all SCID mice with variable survival of such cells. We report here that all SCID mice can be stimulated to produce functional B cells by the transfer of normal neonatal, but not adult, T cells. T cell-induced rescue of C.B-17scid B cells results in high levels of Ig expressing the Ighb allotype of the SCID recipient. These results show that all SCID mice generate some functional B cells, the majority of which do not survive in the absence of a subset of T cells present in high frequency in the neonate.

Aging

Adoptive transfer of human lymphoid cells to severely immunodeficient mice: models for normal human immune function, autoimmunity, lymphomagenesis, and AIDS.

Though the development of human-to-mouse xenotransplant models is in its infancy, astonishing progress has been made in a short period of time. Two experimental applications have been developed: short-term transfer of human lymphocytes to generate models for autoimmunity and infectious diseases, and long-term engraftment of tissues with self-renewal potential. Human PBL-SCID mice have been used by multiple laboratories to study normal and autoimmune antibody responses, and have been shown to be readily infectable with HIV-1. SCID mice grafted with fetal tissue have been developed for studies of HIV-1 infection and its therapy as well as for studies of human hematopoietic cell differentiation. Human tumors appear to grow better in SCID mice than in nude mice, and hu-PBL-SCID mice can develop EBV-related B cell lymphoproliferative disease that resembles the immunoblastic lymphomas appearing in immunosuppressed transplant recipients. There is some evidence of mouse NK cells responding to the human xenograft, and of human T and B cells responding to mouse xenoantigens in these models, but these responses are not generally strong enough to have a major impact on human immune function. The use of these surrogate human models is expected to have a major impact on the understanding and treatment of human disease.

Acquired Immunodeficiency Syndrome

Effective therapy of the LP-BM5 murine retrovirus-induced lymphoproliferative immunodeficiency disease with diethyldithiocarbamate.

The effects of therapy with the immunomodulator diethyldithiocarbamate (DTC) on the manifestation and natural history of LP-BM5 murine retrovirus infection in adult C57 Black 6 mice was investigated. DTC itself, had limited effects on the spleen weight, serum IgM, or mitogen responses of the non-virus-infected control mice when evaluated over a 9-week period. The virus inoculum administered was such that there was approximately a twofold increase in serum IgM and a halving of phytohemagglutinin (PHA) and lipopolysaccharide (LPS) responses in about two weeks and death of all animals by about 26 weeks postinfection. Doses of DTC of 20 and 200 mg/kg weekly or 5 days per week (intraperitoneally) in mice with LP-BM5 infection did not alter the manifestations or course of the disease. Doses of 400 or 600 mg/kg given 5 days per week, starting either 2 weeks before or the day of virus inoculation significantly reduced hypergammaglobulinemia, spleen weight, lymphadenopathy, and also prolonged survival. A dose of 400 mg/kg started 2 weeks after virus inoculation resulted in partial prevention of hypergammaglobulinemia, splenomegaly, and lymphadenopathy as well as 100% survival compared with 12.5% in non-drug-treated controls at 23 weeks after virus inoculation. The 9 surviving animals in the treated group were then allocated to continue treatment or stop treatment. In the animals without further treatment, lymphadenopathy and mortality occurred starting within 6 weeks after cessation of therapy while the animals with continued treatment remained in good condition for 40 weeks. There was only a very limited and transient effect of DTC therapy on the decline of the proliferative responses to phytohemagglutinin or lipopolysaccharide in any of the treated groups in the above described experiments.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome

The immunoglobulin allotype contributed by peritoneal cavity B cells dominates in SCID mice reconstituted with allotype-disparate mixtures of splenic and peritoneal cavity B cells.

We have studied potential regulatory interactions between mature B lymphocyte populations by analysis of C.B-17 severe combined immunodeficient (SCID) mice reconstituted simultaneously with immunoglobulin allotype-congenic mixtures of spleen (SP) and peritoneal cavity (PerC) B cells. We have previously shown that the independent transfer of B cells from these sources leads to the long-term survival of donor B cells and reconstitution of immunoglobulin levels in SCID mice (Riggs, J.E., D.L. Robertson, R.S. Stowers, and D.E. Mosier, manuscript submitted for publication). SP and PerC B cells differ in numerous respects, with the PerC having higher proportions of large, activated B cells that express the IgM greater than IgD phenotype and greater numbers of CD5 B cells. The injection of equal numbers of B cells from SP and PerC into SCID recipients (e.g., BALB/c SP + C.B-17 Per C----SCID) has led to the following observations: (a) serum IgM allotypes in B cell chimeras revealed strict dominance by the allotype contributed by the PerC B cells; (b) this dominance was not due to regulatory T cells; (c) B cells of the unexpressed (i.e., SP) allotype were present in the chimera in the spleen but not the peritoneal cavity; and (d) immunization with TI and TD antigens failed to elicit the SP IgM allotype, whereas secondary TD antigen immunization elicited low levels of the SP IgG2a allotype. Additional experiments demonstrated concurrent expression of IgM allotypes derived from both SP and PerC B cells in recipients that: (a) received a 10-fold excess of SP B cells; (b) received SP B cells before PerC B cell transfer; or (c) received SP B cells intravenously and PerC B cells intraperitoneally. We conclude that the establishment of IgM synthesis by PerC B cells leads to a feedback inhibition of subsequent IgM synthesis by SP B cells, and that the frequency of B cells that can lead to this effect is substantially higher in peritoneal cavity than in spleen. These data provide further confirmation of regulatory interactions between B cells in the absence of T lymphocytes, but confound the interpretation of experiments supporting the existence of a separate CD5+ B cell lineage.

Animals

Autoantibody production by severe combined immunodeficient mice reconstituted with synovial cells from rheumatoid arthritis patients.

In an attempt to characterize the heterogeneity of the human autoantibody response, mice with severe combined immunodeficiency were reconstituted with synovial or blood lymphocytes from patients with rheumatoid arthritis (RA). Mononuclear cells extracted from synovial fluid or tissue (SMC) were a greatly enriched source of IgM rheumatoid factor (RF)-producing cells compared to the peripheral blood mononuclear cells (PBMC) of rheumatoid arthritis patients or normal donors. Six to nine weeks after reconstitution of mice with synovial mononuclear cells, 0%-39.3% (mean = 11.4%) of total IgM consisted of IgM RF compared to 0%-0.15% (mean = 0.02%) in mice given RA PBMC and 0%-1.2% (mean = 0.34%) in mice given normal PBMC. Detectable levels of IgM RF were maintained in some mice for as long as 20 weeks after transfer. Mice reconstituted with synovial membrane or synovial fluid lymphocytes produced a heterogeneous mixture of immunoglobulins. These included other autoantibodies, such as anti-nuclear and anti-cytoplasmic antibodies, and antibodies to exogenous antigens such as the Epstein-Barr virus nuclear antigen-1 (EBNA-1). This heterogeneity is further illustrated by the demonstration that the sera from mice given synovial cells also contained IgG antibodies possessing all three major VH families (VH1, VH3 and VH4) and the four major V kappa families (V kappa 1 to V kappa 4). Autoantibody production gradually decreased with time even under circumstances where total immunoglobulin levels increased, and elevated production could not be induced by antigenic stimulation. These findings describe a new model for the analysis of human autoantibody production.

Animals

Immunodeficient mice xenografted with human lymphoid cells: new models for in vivo studies of human immunobiology and infectious diseases.

This review article deals with the transfer of human lymphoid or hematopoietic tissues to severely immunodeficient mice to create new small animal models for the study of human biology and disease. The degree of functional reconstitution in the three current models is discussed. SCID mice with human grafts have been infected with human immunodeficiency virus (HIV) to generate a small animal model for AIDS research. Epstein-Barr virus (EBV)-related lymphoproliferative disorders can also be modeled by the transfer of adult peripheral blood mononuclear cells to SCID mice.

Animals