Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The role of the recently defined L antigen (a second D region product) in allogeneic and TNP-specific syngeneic primary CML responses has been investigated. The lysis by anti-L specific cytotoxic effector cells was not inhibited when the target cells were pretreated with an antiserum directed against K and D, whereas an antiserum against L completely abrogated this response. Therefore, H-2L products are recognized on the target cell independently of H-2K and H-2D locus products. Both A.SW cells as well as B10 cells were found to respond to Ld alloantigens, in addition to Dd alloantigens when stimulated by cells differing only in the D region. The results of cold target blocking and antiserum inhibition experiments failed to detect cytotoxic cells with specificity of L antigens in association with TNP, under conditions in which TNP-specific effectors to K and D antigens were demonstrable. These findings suggest that there is a more limited involvement of H-2L locus products than the H-2K or H-2D locus products in the induction and specificity of these responses.
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PMID:Properties of H-2L locus products in allogeneic and H-2 restricted, trinitrophenyl-specific cytotoxic responses. 8 79

The H-2da haplotype was derived from the H-2d haplotype by a mutation localized to the D end of the H-2 complex. Coculture of H-2d and H-2da spleen cells gives rise to bidirectional MLR. However, the H-2d anti-H-2da response is much stronger than that of H-2da anti-H-2d. Both haplotypes give rise to reciprocal CML. B10.D2(R103) strain spleen cells, which differ only at the D end of the H-2 complex from the H-2d haplotype, kill H-2da target cells in CML when sensitized to H-2d stimulators and vice versa. Therefore, both the mutant and strain of origin share a D end CML specificity. H-2d and H-2da reject skin grafts in both directions, although some H-2d grafts show prolonged acceptance on H-2da recipients. These data are consistent with a mutation in the D end of the H-2d haplotype resulting in gain-loss of an antigen(s) that gives rise to reciprocal MLR, CML, and skin graft rejection. Further, the mutant can be distinguished from the strain of origin on the basis of the strength of immune response in MLR.
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PMID:Immunogeneic analysis of H-2 mutations. II. Cellular immunity to the H-2DA mutation. 12

Using cytotoxic effector cells of different anti-H-2 specificities, new cell-mediated lympholysis targets, normally undetected on Meth. A tumour cells, were shown after passage with vaccinia or Moloney virus. The H-2d CML targets on Meth. A cells recognized by B10.BR anti-B10.D2 effector cells were presented only after simultaneous vaccinia virus passage, while passage with Moloney virus caused the emergence of H-2b targets. Small but significant killing of vaccinia virus-passaged Meth.A was also obtained by anti-H-2k effector cells. These results are discussed in relation to in vivo experiments: retardation of tumour growth was noted in mice which had received several injections of vaccinia or Moloney virus, showing that the new CML targets were probably acting as transplantation targets.
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PMID:Emergence of foreign H-2-like cytotoxicity and transplantation targets on vaccinia and Moloney virus-infected Meth. A tumour cells. 14

In the cell-mediated lymphocytotoxicity assay, A.TH effector cells sensitized to A.TL lymphocytes lyse not only A.B10.AQR effector cells lyse B10.BR and B10.BYR target cells in addition to B10.AQR cells. These findings indicate that for CML to occur across the IA region barrier, compatibility at K or D regions is not required.
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PMID:Histocompatibility antigens controlled by the I region of the murine H-2 complex. II. K/D region compatibility is not required for I-region cell-mediated lymphocytotoxicity. 83 48

The antigens of the B2m,H-3 region of 13 chromosome 2 congenic strains and seven inbred strains have been studied by using CML and serologic techniques. Nine patterns of cross-reactivity have been defined by CML assays. These results are in agreement with an extend previously described cross-reactivity studies. The reactivities of three monoclonal antibodies previously thought to be reacting with B2M-B are shown to differ: Ly-m11 and J-5 react with cells of strain B10-pa,at and clone 23 does not. Two H-3 region loci are hypothesized on the basis of CML and serologic activity: B2m and H-3. The CTL responses to the B2M antigens are H-2K restricted; the CTL responses to H-3 antigens are H-2D restricted. The restriction of the response to the H-3 antigen requires effector-target identity of the H-2D molecule but not the B2M molecule of the class I antigen. These loci have been separated by recombination from H-42 in the production of the congenic strain B10.FS-a. A gene order of B2m, H-3, H-42 is suggested.
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PMID:CTL and serologically defined antigens of B2m,H-3 region. 241 16

Since tolerogen-specific helper activity is present in MLR-positive class II MHC tolerant mice, a loss of helper activity is unlikely to be responsible for the maintenance of tolerance in these mice. An alternative hypothesis, that effector cell function is selectively down-regulated, has been examined with lymphocytes from MLR-positive class-II MHC tolerant mice on both the A strain and the B10 background. The results demonstrate that lymphocytes from A-strain-tolerant mice were unable to generate tolerogen-specific effector cells in any of the assays tested (CML with or without exogenous growth factor and DTH following in vivo priming or local adoptive transfer), even though these mice possess tolerogen-responsive T helper cells. In contrast, a majority of MLR-positive tolerant mice on the B10 background generated measurable tolerogen-specific cytotoxic activity in the absence of exogenous growth factor, and all the mice examined generated substantial cytotoxic activity in the presence of exogenous growth factor. However, in a local adoptive transfer reaction, lymphocytes from these mice failed to display DTH. It is concluded that tolerance is maintained by selective impairment of class II specific effector functions and that regulation of DTH rather than CTL activity may be central to maintenance of in vivo tolerance to class II MHC antigens.
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PMID:Differential expression of helper versus effector activity in mice rendered neonatally tolerant of class II MHC antigens. 252 2

We investigated the radioresistant (1000 rads) suppression of CML generation mediated by alloactivated murine splenocytes. Suppressive cells were generated in MLCs by stimulation of (A X 6R)F1 splenocytes with irradiated C57BL/10 splenocytes. Suppressive cells could lyse targets bearing H-2b alloantigens, but would not lyse parental B10.T(6R) or B10.A targets. Suppressive activity was detected by including the alloactivated (A X 6R)F1 cells in B10.T(6R) anti-B10.A(1R) MLCs. Relative to the suppressive (A X 6R)F1 cells, the B10.A(1R) lymphocytes display both parental and suppressor-inducing alloantigens. In the absence of a suppressive population, B10.A(1R) stimulators cause B10.T(6R) splenocytes to generate cytolytic activity specific for both H-2Db (suppressor-inducing) and H-2Kk (suppressor-borne) target determinants. The irradiated, alloactivated (A X 6R)F1 cells decrease the H-2Db-specific CML generated in this system, thus mediating apparent antigen-specific suppression. However, cytolytic activity concomitantly generated in the same culture against the unrelated H-2Kk target determinants is similarly reduced by the (A X 6R)F1 cells. Thus, radioresistant suppression by alloactivated splenocytes is not necessarily antigen-specific. The irradiated (A X 6R)F1 cells would not suppress the generation of H-2Kk-specific CTL in B10.T(6R) anti-B10.A MLCs. Hence, the irradiated (A X 6R)F1 cells can impede CML generation against third-party alloantigens if, and only if, those alloantigens are coexpressed with suppressor-inducing alloantigens on the stimulator cells in suppressed MLCs. Similar results were also obtained using a different histoincompatible lymphocyte combination. Since the pattern of suppressor specificity and the pattern of CTL specificity were identical and concomitant under these experimental conditions, these data are consistent with the hypothesis that radioresistant suppression by alloactivated lymphocytes can reflect coincidental in vitro cytolytic T cell function in vitro.
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PMID:Suppression of in vitro cell-mediated lympholysis generation by alloactivated lymphocytes. Examination of radioresistant suppressive activity. 293 77

Fc fragments derived from papain digestion of human IgG have the capacity to augment specific T cell-mediated cytolytic responses. The addition of Fc fragments to cultures containing nylon wool-purified effector and irradiated stimulator cells results in a significant enhancement of the cytotoxic response. Fc fragment-mediated enhancement is restricted to those responses in which the allogeneic differences between effector and stimulator populations encompass the H-2 I region. Significant enhancement of the CML response occurs when differences at H-2 K + I + D (B10 alpha B10.BR) and H-2 I (A.TH alpha A.TL) regions are employed. In contrast strain combinations in which only the H-2 D region (B10.A alpha B10.A(2R)) difference occurs no enhancement is seen. The cellular site of Fc adjuvant action in the CML response is the Lyt-1+2- helper T cell. This was concluded from the finding that Lyt-1+2- helper cells had to be present to obtain Fc-augmented CML responses. The substitution of Interleukin 2 for Lyt-1+2- helper T cells maintained the cytotoxic response, but these responses were not susceptible to the enhancing properties of Fc fragments. Moreover, to achieve enhanced cytotoxic response Fc had to interact only with the cell population.
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PMID:Enhancement of T. lymphocyte functions by Fc fragments of immunoglobulin. II. Augmentation of the cell-mediated lympholysis response occurs through an Lyt-1+2- helper T cell. 645 79

Reconstitution of lethally irradiated mice with a mixture of syngeneic and allogeneic (A+B-->A) bone marrow results in multilineage mixed allogeneic chimerism, donor-specific transplantation tolerance, superior immunocompetence and resistance to graft-vs-host disease. However, the morbidity and mortality associated with lethal irradiation would be a major limitation to the clinical application of chimerism to induce tolerance for solid organ grafts or treat other nonmalignant hematologic diseases. We report here that durable multilineage mixed allogeneic chimerism and donor-specific transplantation tolerance for skin and primarily vascularized allografts can be achieved across multiple histocompatibility barriers using a nonmyeloablative radiation-based approach. The percentage of B10 mouse recipients that engrafted directly correlated with the degree of disparity between donor and recipient and the dose of total body irradiation administered. Although the occurrence of engraftment following conditioning with doses of total body irradiation of > or = 600 cGy was similar for animals receiving bone marrow disparate at MHC or MHC, minor and hematopoietic (Hh-1) loci (67% vs 78%), the level of donor chimerism was significantly less when multiple histocompatibility barriers were present (94.6 +/- 3.8% vs 37.5 +/- 12.5%). Treatment of the recipient with cyclophosphamide 2 days following allogeneic bone marrow transplantation reduced the dose of radiation sufficient for reliable engraftment to only 500 cGy of total body irradiation, regardless of MHC and Hh-1 disparity. Donor chimerism was stable and present in all lineages, with production of lymphoid (T and B cell), NK, and myeloid (erythrocyte, platelet, granulocyte, and macrophage) cells. Mixed chimeras exhibited donor-specific tolerance in vitro, as assessed by mixed lymphocyte culture (MLR) and cytotoxicity (CML) assays, and in vivo to skin and primarily vascularized cardiac allografts. The observation that engraftment and tolerance can be achieved across multiple histocompatibility barriers using nonmyeloablative recipient conditioning may allow allogeneic bone marrow transplantation to be applied to nonmalignant disease states in which lethal conditioning cannot be justified, including the induction of donor-specific tolerance for solid organ transplantation and the treatment of hemoglobinopathies and enzyme deficiency states.
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PMID:A nonlethal conditioning approach to achieve durable multilineage mixed chimerism and tolerance across major, minor, and hematopoietic histocompatibility barriers. 759 73

There is now strong evidence that the BCR-ABL gene product of the Philadelphia chromosome (P210) plays a crucial role in the pathogenesis of chronic myeloid leukemia (CML). We have previously shown that introduction of antisense oligonucleotides into K562 cells could transiently block the expression of P210 and specifically inhibit cellular growth in culture. In this report, we describe the use of a retroviral vector to introduce selected antisense and sense sequences, first into murine B10 cells, previously rendered interleukin-3 (IL-3) independent by transfection of BCR-ABL sequences, and second into K562 cells. The antisense transcripts generated under the control of MoMLV promoter specifically killed B10 cells in the absence of IL-3 and inhibited P210 expression almost completely. In K562 cells, the antisense sequences led to a dramatic reduction of P210 expression and increased their doubling time by more than twofold. This effect was not reversed by the addition of exogenous IL-3 to the culture medium. Control HeLa or HL60 cells infected with the same constructs did not show any change in proliferation rate, despite abrogation of the normal BCR gene products. Rather unexpectedly, P210 suppression was not lethal in K562 cells, showing that such a cell line does not rely entirely on the expression of P210 for surviving, but depends on it as far as growth properties are concerned. We conclude that this approach can successfully achieve stable suppression of the oncogenic protein P210 and may be used to study further the mechanisms by which P210 is transforming cells. The effect on fresh CML cells in bone marrow cultures remains to be assessed before we can tell whether this technique may be used for selective suppression of leukemic hematopoiesis in vitro.
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PMID:Retrovirally transduced antisense sequences stably suppress P210BCR-ABL expression and inhibit the proliferation of BCR/ABL-containing cell lines. 842 66


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