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Lantelme E, Orlando L, Porcedda P, Turinetto V, De Marchi M, Amoroso A, Mantovani S, Giachino C. An in vitro model of T cell receptor revision in mature human CD8+ T cells. Mol Immunol 2007; 45:328-37. [PMID: 17659780 DOI: 10.1016/j.molimm.2007.06.153] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2007] [Revised: 06/07/2007] [Accepted: 06/17/2007] [Indexed: 11/20/2022]
Abstract
V(D)J recombination is a mechanism peculiar to the somatic rearrangement of antigen receptor genes. It requires both expression of the RAG-1 and RAG-2 recombinases and accessibility of the substrate to its recombinase and post-cleavage/DNA repair stage. TCR revision is a genetic correction mechanism that changes T cell specificity by re-activating V(D)J recombination in peripheral T cells. This process is now well described in both normal or pathological murine and human settings. Many of its features, such as the question of whether it occurs in truly mature T cells, remain to be elucidated. Its occurrence in human CD8+ T cells is also an open question. We have therefore established an in vitro model of TCR revision in mature human CD8+ T cells to determine whether down-regulation of the TCR/CD3 complex from the cell surface in the presence of IL7 as a factor favouring chromatin remodelling initiates a TCR revision pathway. Only mature CD8+ T cells carrying already-formed antigen receptors were used. CD8+ T cells treated with anti-CD3 and IL7 showed rearrangement intermediates and expressed new Vbeta-chains on their surface. Investigation of the molecular pathway thus induced disclosed up-regulation of the RAG-2 transcript, but absence of the 'canonical' RAG-1 mRNA. A surprising finding was the demonstration of alternative splice forms of this mRNA, already expressed in untreated CD8+ T cells, encoding for the full-length RAG-1 protein, which was increased three-fold in the treated cells. All the V(D)J requirements were thus fulfilled when mature human CD8+ T cells were stimulated with anti-CD3 and IL7. Induction of TCR revision in vitro in mature T cells is an easily controllable system that could be employed in further studies to elucidate the molecular pathways involved in secondary V(D)J rearrangements in peripheral cells.
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Affiliation(s)
- Erica Lantelme
- Department of Clinical and Biological Sciences, University of Turin, Regione Gonzole 10, 10043 Orbassano, Italy.
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Liu WW, Chen JY, Yang ZQ, Chen SH, Yang LJ, Yu W, Li YQ. [Effects of lead exposure on thymic output naive T cells function]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2007; 25:100-2. [PMID: 17456402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
OBJECTIVE To investigate the levels of T cell receptor rearrangement excision DNA circles (TRECs) within peripheral blood from workers exposed to lead, and thereby to evaluate the number of naive T cells and recent thymic output function. METHODS Quantitative detection of TRECs in peripheral blood mononuclear cells (PBMNC) from 10 cases of workers exposed to lead was performed by real time PCR analysis. 11 workers without exposure to lead served as unexposed controls. In addition, the relationship between TRECs, age, length of service, blood lead, urea lead, blood ZPP and urea delta-ALA was investigated. RESULTS The mean value of TRECs in workers exposed to lead was (2.44 +/- 1.87)/1000 PBMC, significantly under (5.60 +/- 3.96)/1000 PBMC in unexposed controls. A significant negative correlation was found between the TRECs and urea-ALA. But there was no significant correlation between them after controlling for blood lead, urea lead. CONCLUSION Lead exposure may damage thymic output naive T cells function. Furthermore, low-level exposure to lead may damage immune system and earlier than expected.
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Affiliation(s)
- Wei-wei Liu
- Guangzhou Prevention and Treatment Center for Occupational Disease, Guangzhou 510620, China
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De Smedt M, Hoebeke I, Reynvoet K, Leclercq G, Plum J. Different thresholds of Notch signaling bias human precursor cells toward B-, NK-, monocytic/dendritic-, or T-cell lineage in thymus microenvironment. Blood 2005; 106:3498-506. [PMID: 16030192 DOI: 10.1182/blood-2005-02-0496] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Notch receptors are involved in lineage decisions in multiple developmental scenarios, including hematopoiesis. Here, we treated hybrid human-mouse fetal thymus organ culture with the gamma-secretase inhibitor 7 (N-[N-(3,5-difluorophenyl)-l-alanyl]-S-phenyl-glycine t-butyl ester) (DAPT) to establish the role of Notch signaling in human hematopoietic lineage decisions. The effect of inhibition of Notch signaling was studied starting from cord blood CD34(+) or thymic CD34(+)CD1(-), CD34(+)CD1(+), or CD4ISP progenitors. Treatment of cord blood CD34(+) cells with low DAPT concentrations results in aberrant CD4ISP and CD4/CD8 double-positive (DP) thymocytes, which are negative for intracellular T-cell receptor beta (TCRbeta). On culture with intermediate and high DAPT concentrations, thymic CD34(+)CD1(-) cells still generate aberrant intracellular TCRbeta(-) DP cells that have undergone DJ but not VDJ recombination. Inhibition of Notch signaling shifts differentiation into non-T cells in a thymic microenvironment, depending on the starting progenitor cells: thymic CD34(+)CD1(+) cells do not generate non-T cells, thymic CD34(+)CD1(-) cells generate NK cells and monocytic/dendritic cells, and cord blood CD34(+)Lin(-) cells generate B, NK, and monocytic/dendritic cells in the presence of DAPT. Our data indicate that Notch signaling is crucial to direct human progenitor cells into the T-cell lineage, whereas it has a negative impact on B, NK, and monocytic/dendritic cell generation in a dose-dependent fashion.
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Affiliation(s)
- Magda De Smedt
- Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, University Hospital Ghent, Belgium
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Abstract
The role of TCR ligand density (i.e. the number of antigen-MHC complexes) in modulating the diversity of a T cell response selected from a pool of naive precursors remains largely undefined. By measuring early-activation markers up-regulation and proliferation following stimulation with staphylococcal enterotoxin A (SEA), we demonstrate that decreasing the ligand dose below an optimal concentration leads to the delayed activation of a restricted set of TCRVbeta-bearing T cells, with the specific, non-stochastic exclusion of some TCRVbeta+ T cells from the activated pool. Our results suggest that the failure of these TCRVbeta-bearing T cells to reach the activation threshold at sub-optimal ligand concentration is due to the inefficiency of TCR engagement, as measured by TCR internalization, and does not correlate with the relative precursor frequency in the non-immune repertoire. Moreover, even at SEA concentrations that lead to the simultaneous proliferation of all SEA-reactive T cells, we observe marked differences in the ability to secrete cytokines among the different responsive TCRVbeta-bearing T cells. Altogether, our results indicate that the development of a T cell response to a scarce display of ligand significantly narrows TCR repertoire diversity by mechanisms that involve focusing of the repertoire on the expansion of those T cells with the highest avidity of TCR engagement.
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Affiliation(s)
- Pascal M Lavoie
- Laboratoire d'Immunologie, Centre de recherche du Centre Hospitalier de l'Université de Montréal, Hôpital Saint-Luc, Montréal, Québec H2X 1P1, Canada
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Natarajan V, Lempicki RA, Sereti I, Badralmaa Y, Adelsberger JW, Metcalf JA, Prieto DA, Stevens R, Baseler MW, Kovacs JA, Lane HC. Increased peripheral expansion of naive CD4+ T cells in vivo after IL-2 treatment of patients with HIV infection. Proc Natl Acad Sci U S A 2002; 99:10712-7. [PMID: 12149467 PMCID: PMC125022 DOI: 10.1073/pnas.162352399] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Intermittent interleukin-2 (IL-2) therapy has been shown to increase the number of CD4+ T cells, preferentially cells with a naive phenotype, in patients with HIV infection. For this report we investigated the mechanism underlying this expansion by studying the relative roles of peripheral expansion and thymic output. In a cohort of six patients receiving IL-2 over a period of 1 year, the mean number of naive CD4+ T cells increased from 139 to 387 cells per microl while levels of T cell receptor rearrangement excision circles (TRECs) declined from 47,946 to 26,510 copies per 10(6) naive T cells, thus making it unlikely that the CD4+ T cell count increases were secondary to increase in thymic output. To examine directly the impact of IL-2 on peripheral expansion, peripheral blood mature, naive CD4+ T cells were labeled ex vivo with 5-bromodeoxyuridine as well as stained directly for Ki67. These studies revealed a 7-fold increase in the percentage of 5-bromodeoxyuridine-positive cells and a 20-40-fold increase in Ki67 staining in the naive CD4+ T cell pool in the setting of IL-2 administration. This degree of increase in mature CD4+ T cell turnover induced by IL-2 does not compromise the future replicative potential of these cells, because longitudinal measurements of telomere length went from 6,981 to 7,153 bp after 1 year of IL-2 therapy. These data strongly suggest that much of the increase in CD4+ cells associated with IL-2 treatment is caused by peripheral expansion of existing naive CD4+ T cells rather than increased thymic output and that these increases occur without compromising the potential of these cells for further cell division.
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Affiliation(s)
- Ven Natarajan
- Science Applications International Corporation-Frederick, Inc., Frederick, MD 21702, USA
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Abstract
Immune reconstitution is a critical component of recovery after treatment of human immunodeficiency virus (HIV) infection, cancer chemotherapy, and hematopoietic stem cell transplantation. The ability to enhance T-cell production would benefit such treatment. We examined the effects of exogenous interleukin-7 (IL-7) on apoptosis, proliferation, and the generation of T-cell receptor rearrangement excision circles (TRECs) in human thymus. Quantitative polymerase chain reaction demonstrated that the highest level of TRECs (14 692 copies/10 000 cells) was present in the CD1a(+)CD3(-)CD4(+)CD8(+) stage in native thymus, suggesting that TREC generation occurred following the cellular division in this subpopulation. In a thymic organ culture system, exogenous IL-7 increased the TREC frequency in fetal as well as infant thymus, indicating increased T-cell receptor (TCR) rearrangement. Although this increase could be due to the effect of IL-7 to increase thymocyte proliferation and decrease apoptosis of immature CD3(-) cells, the in vivo experiments using NOD/LtSz-scid mice given transplants of human fetal thymus and liver suggested that IL-7 can also directly enhance TREC generation. Our results provide compelling evidence that IL-7 has a direct effect on increasing TCR-alphabeta rearrangement and indicate the potential use of IL-7 for enhancing de novo naïve T-cell generation in immunocompromised patients.
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Affiliation(s)
- Yukari Okamoto
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases and Department of Experimental Transplantation and Immunology, Medicine Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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Garry VF, Tarone RE, Kirsch IR, Abdallah JM, Lombardi DP, Long LK, Burroughs BL, Barr DB, Kesner JS. Biomarker correlations of urinary 2,4-D levels in foresters: genomic instability and endocrine disruption. Environ Health Perspect 2001; 109:495-500. [PMID: 11401761 PMCID: PMC1240309 DOI: 10.1289/ehp.01109495] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Forest pesticide applicators constitute a unique pesticide use group. Aerial, mechanical-ground, and focal weed control by application of herbicides, in particular chlorophenoxy herbicides, yield diverse exposure scenarios. In the present work, we analyzed aberrations in G-banded chromosomes, reproductive hormone levels, and polymerase chain reaction-based V(D)J rearrangement frequencies in applicators whose exposures were mostly limited to chlorophenoxy herbicides. Data from appliers where chlorophenoxy use was less frequent were also examined. The biomarker outcome data were compared to urinary levels of 2,4-dichlorophenoxyacetic acid (2,4-D) obtained at the time of maximum 2,4-D use. Further comparisons of outcome data were made to the total volume of herbicides applied during the entire pesticide-use season.Twenty-four applicators and 15 minimally exposed foresters (control) subjects were studied. Categorized by applicator method, men who used a hand-held, backpack sprayer in their applications showed the highest average level (453.6 ppb) of 2,4-D in urine. Serum luteinizing hormone (LH) values were correlated with urinary 2,4-D levels, but follicle-stimulating hormone and free and total testosterone were not. At the height of the application season; 6/7 backpack sprayers, 3/4 applicators who used multinozzle mechanical (boom) sprayers, 4/8 aerial applicators, and 2/5 skidder-radiarc (closed cab) appliers had two or more V(D)J region rearrangements per microgram of DNA. Only 5 of 15 minimally exposed (control) foresters had two or more rearrangements, and 3 of these 5 subjects demonstrated detectable levels of 2,4-D in the urine. Only 8/24 DNA samples obtained from the exposed group 10 months or more after their last chlorophenoxy use had two rearrangements per microgram of DNA, suggesting that the exposure-related effects observed were reversible and temporary. Although urinary 2,4-D levels were not correlated with chromosome aberration frequency, chromosome aberration frequencies were correlated with the total volume of herbicides applied, including products other than 2,4-D. In summary, herbicide applicators with high urinary levels of 2,4-D (backpack and boom spray applications) exhibited elevated LH levels. They also exhibited altered genomic stability as measured by V(D)J rearrangement frequency, which appears reversible months after peak exposure. Though highly detailed, the limited sample size warrants cautious interpretation of the data.
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Affiliation(s)
- V F Garry
- Environmental Medicine and Pathology Laboratory, University of Minnesota, Minneapolis, Minnesota 55414-3290, USA.
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Koishi S, Kubota M, Sawada M, Hirota H, Hashimoto H, Lin YW, Watanabe K, Usami I, Akiyama Y, Furusho K. Biomarkers in long survivors of pediatric acute lymphoblastic leukemia patients: late effects of cancer chemotherapy. Mutat Res 1998; 422:213-22. [PMID: 9838123 DOI: 10.1016/s0027-5107(98)00199-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In order to elucidate the late effects of cancer chemotherapy, mutant frequencies (Mfs) at the hypoxanthine phosphoribosyl transferase (hprt) locus were evaluated in pediatric patients with early pre-B acute lymphoblastic leukemia (ALL). Hprt-Mfs were measured at least 2 years after completion of chemotherapy. Ten out of 15 patients were found to have hprt-Mfs exceeding the 99% confidence limits as calculated from observations of healthy controls. Although there was some intraindividual variation, serial measurements of hprt-Mfs with intervals of more than 6 months revealed that hprt-Mfs were fairly stable. Patients with high Mfs tended to have sibling clones as detected by clonality analysis using the T-cell receptor (TCR) rearrangement pattern, but clonality did not have a major effect on the Mfs. On the other hand, Mfs at the TCR locus and sister chromatid exchange frequency were within the normal range in all patients. These data suggest that chemotherapy can cause persistent genotoxicity in vivo in a subset of pediatric ALL patients and that the hprt-Mf is a useful method for measuring such an effect.
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Affiliation(s)
- S Koishi
- Department of Pediatrics, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606, Japan
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Tsuda S, Rieke S, Hashimoto Y, Nakauchi H, Takahama Y. Il-7 supports D-J but not V-DJ rearrangement of TCR-beta gene in fetal liver progenitor cells. J Immunol 1996; 156:3233-42. [PMID: 8617945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The rearrangement of TCR-beta gene, one of the earliest events in T cell development, consists of two consecutive steps: D-J rearrangement and V-DJ rearrangement. The present study examined the signals supporting D-J beta and V-DJ beta rearrangements during early T cell development from progenitor cells that reside in fetal liver. We have found that there is an interval of 1 to 2 days between D-J beta and V-DJ beta rearrangements during the early T cell development from fetal liver progenitor cells in deoxyguanosine-treated thymus lobes. We have also found that IL-7, a cytokine expressed in the subcapsular area of the thymus, can promote D-J beta rearrangement of fetal liver progenitor cells, and that anti-IL-7 and anti-IL-7R Abs inhibit the D-J beta rearrangement and further T cell development of fetal liver progenitor cells in the thymus environment. Interestingly, unlike the thymus environment, IL-7 alone was not capable of supporting V-DJ beta rearrangement in the fetal liver cell cultures. These results indicate that D-J beta rearrangement during fetal liver-derived early T cell development is supported in the thymus by IL-7. Furthermore, the present results demonstrate that IL-7, supporting D-J beta rearrangement, does not promote V-DJ beta rearrangement of fetal liver progenitor cells, suggesting that intrathymic molecules promoting V-DJ beta rearrangement are distinct from IL-7 that supports the D-J beta rearrangement.
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Affiliation(s)
- S Tsuda
- Department of Immunology, Institute of Basic Medical Sciences, University of Tsukuba, Japan
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Hayes SM, Sirr A, Jacob S, Sim GK, Augustin A. Role of IL-7 in the shaping of the pulmonary gamma delta T cell repertoire. J Immunol 1996; 156:2723-9. [PMID: 8609389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Gamma delta T cells bearing the canonical fetal-type V gamma 6/V delta 1 rearrangements are the predominant gamma delta T cells in the lungs of adult mice. In contrast, these V gamma 6/V delta 1 T cells are virtually absent in the pulmonary epithelia of nude mice. The intraepithelial dominance of gamma delta T cells that express this particular TCR is thought to result from a preferred thymic pathway of gene rearrangement and not from TCR-mediated positive selection. We now show that gamma delta T cell precursors in the lung epithelium of both euthymic and athymic neonatal mice generate this rearrangement in situ. In athymic mice, these clonotypes do not survive, but can be rescued in vitro and in vivo by the lymphokine IL-7.
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MESH Headings
- Animals
- Animals, Newborn
- Base Sequence
- Cell Differentiation/drug effects
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Cells, Cultured
- Embryonic and Fetal Development/drug effects
- Embryonic and Fetal Development/genetics
- Embryonic and Fetal Development/immunology
- Gene Rearrangement, T-Lymphocyte/drug effects
- Gene Rearrangement, T-Lymphocyte/immunology
- Interleukin-7/physiology
- Lung/growth & development
- Lung/immunology
- Lung/metabolism
- Mice
- Mice, Inbred BALB C
- Mice, Nude
- Molecular Sequence Data
- RNA, Messenger/immunology
- Receptors, Antigen, T-Cell, gamma-delta/drug effects
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/immunology
- T-Lymphocytes/drug effects
- T-Lymphocytes/immunology
- T-Lymphocytes/metabolism
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Affiliation(s)
- S M Hayes
- Department of Medicine, National Jewish Center for Immunology and Respiratory Medicine, Denver, CO 80206, USA
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Mattano SS, Zimmer DM, Harbach PR, Hunter TC, Aaron CS. Southern blot analysis of T-cell receptor gene rearrangements in cynomolgus monkeys, and identification of a progenitor cell HPRT mutation. Environ Mol Mutagen 1995; 26:119-126. [PMID: 7556108 DOI: 10.1002/em.2850260205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Increases in peripheral blood T-lymphocyte HPRT mutant frequency may reflect either a number of independent HPRT gene mutational events or clonal proliferation of a single HPRT mutant. Sequence analysis of HPRT mutations in conjunction with T-cell receptor (TCR) gene rearrangement pattern analysis can distinguish these possibilities. Our laboratory previously characterized a nonhuman primate model for in vivo mutation studies using the clonal HPRT mutation assay. In the present study we report the use of probes for human TCR beta and gamma genes to characterize TCR rearrangements in cynomolgus monkeys. Together, these methods were used to examine a monkey which exhibited a mean spontaneous HPRT mutant frequency (MF) of 16.4 x 10(-6), compared to the normal mean MF of 3.03 x 10(-6). The elevated MF resulted from the occurrence of a single HPRT mutation in a lymphocyte progenitor cell or stem cell, since T-cell clones isolated from the monkey exhibited a G to T transversion at base pair 539 in the HPRT coding region, and had unique rearrangements of TCR gamma along with an apparent germline TCR beta configuration. In a preliminary in vivo mutation study, the animal was treated with the investigational potent mutagen and antitumor agent adozelesin (U-73975). No increase in HPRT mutant frequency was observed. The HPRT mutant clones isolated after treatment showed rearrangement of both TCR gamma and beta genes. Possible explanations for these findings are discussed.
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MESH Headings
- Animals
- Antineoplastic Agents, Alkylating/toxicity
- Base Composition
- Base Sequence
- Benzofurans
- Blotting, Southern
- Cells, Cultured
- Cloning, Molecular
- Cyclohexanecarboxylic Acids/toxicity
- Cyclohexenes
- DNA Primers/chemistry
- Drugs, Investigational
- Duocarmycins
- Gene Rearrangement, T-Lymphocyte/drug effects
- Gene Rearrangement, T-Lymphocyte/genetics
- Humans
- Hypoxanthine Phosphoribosyltransferase/drug effects
- Hypoxanthine Phosphoribosyltransferase/genetics
- Indoles
- Macaca fascicularis
- Molecular Sequence Data
- Mutation/genetics
- Nucleic Acid Hybridization
- Receptors, Antigen, T-Cell/drug effects
- Receptors, Antigen, T-Cell/genetics
- Stem Cells/cytology
- Stem Cells/drug effects
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Affiliation(s)
- S S Mattano
- Upjohn Company, Kalamazoo, Michigan 49001, USA
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Abstract
In Africa, hyper-reactive malarial splenomegaly (HMS), which is also known as tropical splenomegaly syndrome, can be associated with a prominent lymphocytosis in blood and bone marrow that is difficult to distinguish clinically from chronic lymphocytic leukaemia (CLL). The observation that some patients with HMS become resistant to treatment with anti-malarial drugs has led to the suggestion that HMS may evolve into a malignant lymphoproliferative disorder. To test this hypothesis, 22 Ghanaian patients with HMS and/or lymphocytosis were categorised by degree of response to proguanil according to standard clinical criteria, and DNA was extracted from peripheral blood cells and screened for rearrangements of the Jh region of the immunoglobulin gene with a DNA probe. Clonal rearrangements of the Jh region were found in all 3 patients with no response, in none of 13 patients with sustained response, and in 2 of 6 patients with moderate response or relapse on proguanil therapy. The detection of such rearrangements, and hence clonal lymphoproliferation in individuals with clinical features intermediate between HMS and CLL, supports the hypothesis that HMS may evolve into a malignant lymphoproliferative disorder.
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MESH Headings
- Adolescent
- Adult
- Aged
- Animals
- Child
- DNA Probes
- Drug Resistance
- Evaluation Studies as Topic
- Female
- Gene Rearrangement, T-Lymphocyte/drug effects
- Gene Rearrangement, T-Lymphocyte/genetics
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/complications
- Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Lymphocytosis/drug therapy
- Lymphocytosis/etiology
- Lymphocytosis/genetics
- Malaria/complications
- Malaria/drug therapy
- Malaria/genetics
- Male
- Middle Aged
- Mutation/genetics
- Plasmodium falciparum
- Proguanil/therapeutic use
- Receptors, Immunologic/genetics
- Splenomegaly/drug therapy
- Splenomegaly/etiology
- Splenomegaly/genetics
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Affiliation(s)
- I Bates
- Division of Haematology, St George's Hospital Medical School, London, UK
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