乳腺癌淋巴结微转移患者克隆性T细胞TCRα链CDR3谱型分析

目的 分析乳腺癌微转移淋巴结T细胞克隆性增生及TCR α链谱型偏移情况,了解抗肿瘤T细胞克隆的分子特征。方法 利用RT-PCR扩增10例乳腺癌微转移淋巴结T细胞32个TCR可变区（AV）亚家族的基因,基因扫描检测T细胞克隆性及TCR AV亚家族取用情况,对单克隆家族行PCR扩增TCR α链全长序列,构建重组质粒后测序,分析互补决定区（CDR3）序列。结果 乳腺癌淋巴结微转移患者T细胞呈单、寡克隆、寡克隆趋势和多克隆增生,不同患者表达1～4个TCR AV亚家族。克隆性T细胞的CDR3氨基酸序列不同,但是病例4和病例8含有相同的CDR3氨基酸基序：AM和DDKII。结论 乳腺癌TCR AV基因表达具有多样性特点,TCR AV家族的取用可能与乳腺癌肿瘤抗原的多样性和不同个体的免疫应答反应有关。相同CDR3氨基酸基序的发现可能对乳腺癌的T细胞介导免疫治疗提供帮助。     

CD4+ and CD8+ T-Cell Skewness in Classic Kaposi Sarcoma

It is widely accepted that a deranged immune system plays a key role in the onset and evolution of classic Kaposi sarcoma (CKS). Nevertheless, the usage of the T-cell receptor (TCR) β-variable (BV) chain repertoire expressed by peripheral blood lymphocytes in patients with CKS is still unknown. With the aim of providing some further insights into the complex role of the immune system in CKS pathogenesis, we performed an extensive analysis of the TCR BV repertoire in both CD4⁺ and CD8⁺ T cells in 30 human herpesvirus 8-positive Sardinian patients with CKS and an equal number of age-matched healthy controls. We used a panel of monoclonal antibodies covering approximately 70% of human BV subfamilies and third complementarity determining region (CDR3) spectratyping. Patients with CKS showed an increased frequency of BV expansions in both CD4⁺ and CD8⁺ lymphocytes, with no prevalent clones. On spectratyping analysis, most of the 720 BV CDR3 profiles obtained from both CD4⁺ and CD8⁺ T cells in patients with CKS were skewed. In particular, the surprising increase of BV skewing observed in CD4⁺ lymphocytes mimics the pattern of progressive TCR BV narrowing described in responses to persistent viral antigen stimulations. Our findings support the hypothesis that CKS evolution is associated with inadequate activation rather than impairment of the immune system.     

Immunosuppressive treatments for myelodysplastic syndromes

The myelodysplastic syndromes (MDS) comprise a heterogeneous group of clonal hematopoietic stem cell disorders, while, immunological abnormalities are frequently observed in patients with MDS. Several reports revealed that about 10% of MDS patients have clinical autoimmune disorders like skin vasculitis, rheumatic disease, or autoimmune hemolytic anemia. Furthermore, serological immunological abnormalities like hyper- or hypogammaglobulinemia, positivities of antinuclear antibody, positivities of direct Coombs test, or inverted CD4/8 ratios were found in 18-65% of patients with MDS. Recently immunosuppressive therapies including prednisolone, antithymocyte globulin, and cyclosporin A (CsA) are used to treat cytopenia in some patients with MDS. We examined the efficacy of CsA in 50 patients with MDS. Hematologic improvement was observed in 30 (60%) patients especially for erythroid lineage. There were significantly more responders with good karyotype or DRB1*1501 than with intermediate/poor karyotypes or with other HLA types. MDS with erythroid hypoplasia is a rare form of MDS, and has not yet been clearly defined. We reported four patients with MDS with erythroid hypoplasia who had morphological evidence of myelodysplasia and low percentage of erythroid precursors. Rearrangements of the TCR- βand - γgenes were seen in these patients using Southern blot and PCR analysis. Also they had skewed TCR usages using TCR repertoire analysis. Their anemia drastically improved with CsA therapy. We have to establish the clinical usefulness of immunosuppressive therapy in MDS patients and simple tools for revealing T-cell mediated myelosuppression in the individual patients for decision-making.     

Prevalence and clinical association of clonal T-cell expansions in Myelodysplastic Syndrome.

Selected patients with Myelodysplastic Syndromes (MDS) are responsive to immunosuppressive therapy, suggesting that hematopoietic suppressive T cells have a pathogenic role in ineffective hematopoiesis. We assessed T-cell receptor (TCR) clonality through combined flow cytometry and molecular analysis of the complementarity determining region (CDR)-3 of the T-cell receptor-Vbeta gene. We identified clonal T cells in 50% of MDS patients (n=52) compared to 5% of age-matched normal controls (n=20). The presence of T-cell clones was not associated with features linked previously to immunosuppression response, including WHO diagnostic category, karyotype, marrow cellularity, IPSS category, sex or age 相似文献   

外周T细胞淋巴瘤TCR基因重排及CDR3谱型分析

 目的　分析外周T细胞淋巴瘤穿刺标本中T细胞受体（TCR）β链克隆性基因重排及互补决定区3（CDR3）谱型。方法　应用RT-PCR扩增TCR Vβ24个亚家族的CDR3基因,并经基因扫描确定T细胞克隆性,对提示单克隆或寡克隆增生亚家族的PCR产物测序分析其CDR3序列。结果　4例淋巴瘤患者TCR表达受到明显抑制,仅表达1～4个Vβ亚家族。所有患者均存在1个或多个Vβ亚家族的克隆增生T细胞,增生形式包括单克隆、双克隆及寡克隆增生趋势。CDR3区序列分析证实增生的T细胞克隆具有不同的氨基酸序列。结论　外周T细胞淋巴瘤患者存在T细胞克隆性增生,其TCR Vβ呈限制性取用,不同克隆T细胞具有不同的CDR3谱型。     

Biased usage of BV gene families of T‐cell receptors of WT1 (Wilms’ tumor gene)‐specific CD8+ T cells in patients with myeloid malignancies

(Cancer Sci 2010; 101: 594–600) WT1 (Wilms’ tumor gene 1) protein is a potent pan‐tumor‐associated antigen (TAA) and WT1‐specific cytotoxic T lymphocytes (WT1 tetramer⁺ CD8⁺ T cells) are spontaneously induced in patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS). We conducted a single‐cell level comparative analysis of T‐cell receptor β‐chain variable region (TCR‐BV) gene families of a total of 1242 spontaneously induced WT1 tetramer⁺ CD8⁺ T cells in HLA‐A*2402⁺ patients with AML or MDS and those in healthy donors (HDs). This is the first report of direct usage analysis of TCR‐BV gene families of individual TAA‐specific CD8⁺ T cells at single‐cell level. Usage analysis using single‐cell RT‐PCR of TCR‐BV gene families of individual FACS‐sorted WT1 tetramer⁺ CD8⁺ T cells showed for the first time (i) that BVs 5, 6, 20, and 27 were commonly biased in both HDs and patients; (ii) that BV4 was commonly biased in HDs and MDS patients; (iii) that BV19 was commonly biased in the patients; and (iv) that BVs 7 and 28, BVs 9 and 15, and BVs 12 and 29 were specifically biased in HDs, AML, and MDS patients, respectively. However, statistical analysis of similarity among HD, AML, and MDS of individual usage frequencies of 24 kinds of TCR‐BV gene families indicated that the usage frequencies of TCR‐BV gene families in AML and MDS patients reflect those in HDs. These findings represent a novel insight for a better understanding of WT1‐specific immune response.     

TCR spectratyping revealed T lymphocytes associated with graft-versus-host disease after allogeneic hematopoietic stem cell transplantation

Clonal expansion of T cells after allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been observed, but their characteristics remain to be fully elucidated. We report here that CD8(+) T cells were the dominant T lymphocytes seen and T-cell repertoire diversity decreased dramatically during the first 3 months after allo-HSCT. Patients with GVHD grade II - IV had significantly lower T-cell repertoire diversity compared with non-GVHD patients. TCR beta variable gene (TCRBV) subfamily 8, 5.1, 5.2, 4, and 13 were the five most frequently expanded subfamilies among these patients. Among the 49 over-expanded clones identified, clonotype "TCR3-5" and "TCR18-5" were isolated from four patients with HLA-A2 allele and skin GVHD. Their frequencies correlated well with skin symptoms (i.e. rash). Moreover, they were detected in donors but not detected in recipients before transplantation. Lastly, three common TCRBV CDR3 motifs shared by T cells related with GVHD were discovered: TGDS, GLAG, and GGG. These findings suggest that TCR spectratyping is helpful for revealing GVHD-related T cells and may have utility in early diagnosis.     

白血病单倍型骨髓移植后T细胞克隆的T细胞受体分子特征

背景与目的:临床及实验研究结果表明,异基因造血干细胞移植后T细胞免疫恢复延迟,单倍型造血干细胞移植免疫重建与临床经过密切相关.本课题通过T细胞受体谱型分析,研究白血病单倍型骨髓移植后细胞免疫重建特点及与移植物抗宿主病(GVHD)相关的T细胞克隆的T细胞受体β链可变区互补决定3区(TCRBV CDR3)分子特征.方法:应用RT-PCR扩增9例不同类型白血病单倍型骨髓移植后患者及5名正常供者的外周血的TCRBV 24个家族的基因序列,并通过基因扫描的方法判断TCRBV家族的克隆表达情况、CDR3克隆性质及测定BV家族的利用率.对于单克隆表达的与GVHD相关T细胞克隆进行序列测定.结果:在移植后10～19个月,TCRBV家族的利用仍处于不均一状态,检测到部分BV家族缺失,部分家族出现寡克隆、单克隆T细胞增殖.在疾病相对稳定的4例患者中,在9～14个BV家族中有表达,且多克隆家族的表达率在50%以上.另5例为疾病处于活动状态,发生Ⅱ～Ⅲ度GVHD或巨细胞病毒(CMV)感染,对BV家族的利用明显减少,多为单克隆或寡克隆表达,多克隆表达率仅30%,未发现共用的单克隆BV家族.其中2例患者在治疗前后不同时间,随着疾病趋于稳定,BV家族的利用增加,CDR3的多克隆群体增加.得到的一组与GVHD直接相关的TCRBV CDR3分子,通过比较未发现共同使用的氨基酸基序.结论:单倍型骨髓移植后10～19个月,在疾病相对稳定期,9～12个BV家族有表达,以多克隆家族表达为主.在疾病活动状态,BV家族表达减少,以单克隆或寡克隆表达为主.与GVHD相关的克隆性T细胞,未发现共同使用的CDR3氨基酸基序.     

Enteropathy-type T-cell lymphoma expressing NK-cell intraepithelial lymphocyte (NK-IEL) phenotype

Enteropathy-type T-cell lymphoma (ETL) is an intraepithelial T-lymphocyte (T-IEL) tumor. The tumor cells are usually CD3+, CD4-, CD8+, and contain cytotoxic granule associated proteins. We report on a CD3-negative CD56-positive enteropathy-associated lymphoma (ETL). This is the first case report of CD3-negative, CD56-positive, CD94-negative, and CD161-positive ETL. ETL cells originate from intraepithelial T-lymphocytes of the intestine. CD3-negative intraepithelial lymphocytes are known as natural killer (NK)-IELs. The phenotype of NK-IELs is also CD3-negative, CD56-positive, CD94-negative, and CD161-positive, while most normal NK cells express CD56 and CD94. CD3-negative lymphoma cells in this report also expressed CD56 and CD161, but not CD94. Because Southern blotting analysis showed a rearrangement of T-cell receptor (TCR) Cbeta in this case, the tumor is classified as an ETL. Based on the findings, NK-IELs may originate from T-cells, not NK-cells.     

Alterations in the T-cell receptor variable beta gene-restricted profile of CD8+ T lymphocytes in the peripheral circulation of patients with squamous cell carcinoma of the head and neck.

PURPOSE: Apoptosis of activated CD8(+) T cells is often seen in tumor-infiltrating lymphocytes and circulating peripheral blood mononuclear cells (PBMC) in patients with squamous cell carcinoma of the head and neck (SCCHN). We investigated whether T-cell receptor (TCR) variable beta chain (Vbeta)-restricted T cells were more sensitive to apoptosis than non-TCR Vbeta-restricted T cells. EXPERIMENTAL DESIGN: Flow cytometry analysis with anti-TCR Vbeta antibodies was used to define expansions and contractions of Vbeta-restricted T cells in patients with SCCHN relative to normal donors. This staining was combined with Annexin V binding to indicate early T-cell apoptosis. RESULTS: The TCR Vbeta profiles of CD3(+) T cells in tumor-infiltrating lymphocytes and PBMCs of patients with SCCHN were altered relative to controls, with one to five expansions and numerous contractions of TCR Vbeta-restricted T cells detected. These types of alterations were significantly greater in CD8(+) than CD4(+) T cells. Enhanced Annexin V binding to CD8(+) T cells was evident in PBMCs obtained from all patients, with 3 of 13 showing preferential targeting for apoptosis of TCR Vbeta-restricted T cells. CONCLUSIONS: TCR Vbeta profiles of CD8(+) T cells were altered in patients with SCCHN relative to normal controls. This may reflect increased apoptosis of expanded or contracted CD8(+) T cells, which define the TCR Vbeta profile of antigen-responsive T-cell populations in patients with cancer.     

Tumor cytolysis by lymphocytes infiltrating ovarian malignant ascites

Tumor-associated lymphocytes (TAL) were isolated from the ascitic fluid of patients with adenocarcinoma of the ovary. These cells proliferated and expanded by 100-600-fold as either CD3+ CD4+ or CD3+ CD8+ cultures in the presence of moderate concentrations (50-200 cetus units/ml) of recombinant interleukin 2 and reached high numbers (5 x 10(8)-1 x 10(9)). After expansion of 16 TAL samples from 15 patients, 5 of the 7 isolated ovarian cytotoxic T-lymphocyte cell lines of T-cell receptor (TCR) (alpha beta)+ CD3+ CD8+ CD4- phenotype exhibited preferential cytolytic activity against autologous tumor targets and significantly lower cytolytic activity against allogeneic tumor targets and the natural killer-sensitive cell line K562. The cytolytic activity of the CD8+ TAL was inhibited by operationally anti-TCR (alpha beta) monoclonal antibody and monoclonal antibody specific for the CD3 differentiation antigen, indicating that the TCR and CD3 are involved in the cytolytic process. The other TAL cultures demonstrated similar cytolytic activity against both autologous and allogeneic tumors. The phenotype of these TAL was predominantly TCR (alpha beta)+ CD3+ CD4+ CD8-. Certain CD3+ CD8+ T-cell clones isolated from representative TAL exhibited preferential autologous tumor-specific cytotoxicity that may be major histocompatibility complex restricted. Other CD3+ CD8+ and CD3+ CD4+ clones exhibited nonmajor histocompatibility complex restricted cytotoxicity. These results demonstrate that CD3+ CD4+ and CD3+ CD8+ T-cells present in the ovarian malignant ascites can be propagated in large numbers and for long time intervals as T-cell lines in vitro. This finding may be significant for further investigation of ovarian tumor-specific cytotoxic T-lymphocytes and future adoptive specific immunotherapy studies.     

乳腺癌患者T细胞受体基因重排及CDR3区序列分析

 目的　分析乳腺癌转移淋巴结穿刺标本中T细胞受体（TCR）β链克隆性基因重排及互补决定区3（CDR3）区序列。方法　应用RT-PCR扩增2例反应性增生淋巴结及3例乳腺癌转移淋巴结T细胞24个TCR Vβ亚家族的CDR3基因,并经基因扫描确定T细胞克隆性,对提示单克隆或寡克隆增生亚家族的PCR产物进行测序。结果　乳腺癌转移淋巴结T细胞中TCR存在限制性取用,仅表达3～5个Vβ亚家族。增生的T细胞存在克隆性特点,增生形式包括寡克隆及多克隆。CDR3区序列分析证实增生的T细胞克隆具有不同的氨基酸序列。结论　乳腺癌转移淋巴结中存在T细胞克隆性增生,其TCR Vβ呈限制性取用,不同T细胞克隆的CDR3序列不同。     

Characterization of T-cell memory phenotype after in vitro expansion of tumor-infiltrating lymphocytes from melanoma patients

Memory T-cell populations in human antitumor tumor-infiltrating lymphocytes (TILs) for adoptive cell transfer have not been fully characterized. Our studies demonstrated that CD62L, CD27 and CD28 positive effector memory T-cells were present in the TIL samples from the tumor tissues of melanoma patients and T-cell expansion led to the significant loss of memory T-cells. CD27- and CD28-positive T-cells had high levels of CD44 expression. T-Cell expansion resulted in significant down-regulation of CD44 expression. Interleukin-2 (IL-2) and anti-CD3 antibody stimulation may be responsible for CD44 down-regulation on CD8(+) T-cells during expansion. Furthermore, CD44 down-regulation using small interfering RNA (siRNA) on TILs dramatically reduced interferon-gamma and IL-2 release upon tumor stimulation. These results suggest that the regulation of CD44 expression in TILs may play an important role in memory T-cell maintenance and antitumor immune response.     

B细胞非霍奇金淋巴瘤TCR基因重排及CDR3谱型分析

 目的　分析B细胞淋巴瘤穿刺标本中T细胞受体（TCR）β链克隆性基因重排及互补决定区3（CDR3）谱型。方法　应用RT-PCR扩增TCR Vβ24个亚家族的CDR3区基因,并经基因扫描确定T细胞克隆性,对提示单克隆或寡克隆增生亚家族的PCR产物进行测序。结果　3例淋巴瘤患者TCR存在限制性取用,仅表达2～5个Vβ亚家族。所有患者均存在克隆性增生T细胞,增生形式包括寡克隆及寡克隆增生趋势。CDR3区序列分析证实增生的T细胞克隆具有不同的氨基酸序列。结论　B细胞淋巴瘤患者存在T细胞克隆性增生,其TCR Vβ呈限制性取用,不同克隆T细胞的CDR3序列不同。     

T-cell subset analysis of Lewis lung carcinoma tumor rejection: heterogeneity of effectors and evidence for negative regulatory lymphocytes correlating with metastasis.

We have analyzed the phenotypes of the T-cell subsets generated in response to Lewis lung carcinoma clones in C57BL/6J recipients. The metastatic derivative, which expresses low levels of H-2Kb gene, predominantly elicited CD8, V beta 8, and V beta 9+ T-cells. The nonmetastatic clone expressing high levels of H-Kb gene triggered a more heterogeneous response of V beta-5, -6, -8, -9, and -11 CD8+ T-cells. Comparison of the T-cell receptor (TCR) expression of the T-cells infiltrating the tumor site with the lymphocytes in the periphery of tumor-bearing animals revealed a pattern of homing of CD4+ T-cells bearing V beta-5, -6, and -11 TCR chains and CD8+ T-cells bearing V beta-5, -6, -9, and -11. Depletion of V beta 5 or V beta 6+ T-cells correlated with accelerated tumor growth, implying their protective role as tumor-specific effectors and consistent with the cytotoxicity of T-cells with this TCR phenotype. V beta 11 TCR expression in the tumor-infiltrating lymphocytes increased with the tumor size. Depletion of V beta 11+ T-cells enhanced resistance to primary tumor growth and conferred protection from metastasis in recipients cleared of V beta 5 and V beta 6 T-cell subsets. Those results suggest that tumor-specific effectors as well as negative regulator T-cells home, infiltrate, and coexist in the tumor site.     

Peptide-specific CD8+ T-cell evolution in vivo: response to peptide vaccination with Melan-A/MART-1

Monitoring of CD8+ T-cell responses in cancer patients during peptide vaccination is essential to provide useful surrogate markers and to demonstrate vaccine efficacy. We have longitudinally followed CD8+ T-cell responses in 3 melanoma patients who were immunized with peptides derived from Melan-A/MART-1. Recombinant HLA-A2 tetramers loaded with the naturally presented Melan-A/MART-1 nonamer peptide (AAGIGILTV) and the Melan-A/MART-1 analog (ELAGIGILTV) were used in combination with phenotypical analysis for different T-cell subsets including naive T cells, effector T cells, "true memory" T cells and "memory effector" T cells, based on CD45RA/RO and CCR7-expression. At least in a single patient, T cells binding to the AAGIGILTV epitope were detected in naive, precursor (CD45RA+/CCR7+) CD8+ T cells, and CD8+ T cells binding to the analog ELAGIGILTV peptide were identified in the terminally differentiated (CD45RA+/CCR7-) T-cell subset. Molecular and functional analysis of tetramer-binding T cells revealed that the T-cell receptor (TCR) repertoire was oligo/polyclonal in AAGIGILTV-reactive T cells, but different and restricted to a few TCR clonotypes in ELAGIGILTV-reactive T cells prior to vaccination. The TCR repertoire reactive with Melan-A/MART-1 peptide epitopes was broadened during vaccination and exhibited a different profile of cytokine release after specific stimulation: tetramer-binding T cells from 2/3 patients secreted granulocyte/macrophage colony-stimulating factor (GM-CSF) and interferon-gamma but not interleukin-2 (IL-2) in response to Melan-A/MART-1 peptides. In the third patient, tetramer-binding T cells secreted IL-2 exclusively. Our results show that T-cell responses to peptide vaccination consist of different T-cell subsets associated with different effector functions. Complementary analysis for TCR CDR3 and cytokine profiles may be useful to define the most effective CD8+ T-cell population induced by peptide vaccination.     

Dominant rearrangements among human tumor-infiltrating lymphocytes. Analysis of T-cells derived from 32 patients with melanoma, lung, and renal cell carcinoma.

Dominant rearrangements of T-cell receptor (TCR) beta-chain genes are reported among tumor-infiltrating lymphocytes (TIL). After interleukin-2 expansion of TIL from renal and lung carcinoma and melanoma biopsy tissues, rearrangements of TCR beta-chain genes were analyzed by Southern blotting. Nongermline restriction fragments, indicating dominant rearrangements, were detected among the TIL from all 6 patients with renal cell carcinoma, 17 of 20 patients with melanoma, and 3 of 6 patients with lung tumors. The restriction-fragment sizes of these dominant rearrangements were heterogeneous among the various patients. Rearrangements into C beta 1 were more common than C beta 2 rearrangements. Phenotypic analyses indicated that dominant rearrangements occurred in both CD4 and CD8 predominant TIL populations. The TIL populations that were extracted were expanded to derive large cell numbers suitable for in vivo transfer in an interleukin-2 and TIL immunotherapy program. The data indicated that the cells delivered to these patients usually were characterized by dominant populations of T-cells with selective TCR gene rearrangements. The significance of selective TCR use requires evaluation of the function and specificity of the TIL comprising these dominant populations both in their native in vivo setting and in the context of therapeutic transfer.     

Clonal change of infiltrating T-cells in children with familial hemophagocytic lymphohistiocytosis: possible association with Epstein-Barr virus infection

BACKGROUND: Although familial hemophagocytic lymphohistiocytosis (FHL) has been considered a T-cell disorder, to the authors' knowledge there are no previous reports on the clonal basis of FHL. In the current study the authors analyzed the clonality of T-cells in two FHL patients at the time of disease onset and at disease progression. METHODS: Patient 1 had FHL and died of recurrent disease 4 months after bone marrow transplantation (BMT). His liver and spleen showed massive infiltrations of CD3+, CD4-, and CD8+ T-cells. The Epstein-Barr virus (EBV) genome was detected by in situ hybridization. Patient 2 also had FHL and died of progressive disease 9 weeks after the onset of disease despite chemotherapy. A polymerase chain reaction (PCR) analysis showed positive EBV genome in the peripheral blood, liver, and spleen of Patient 2. In the two patients, T-cell receptor-beta and alpha-chain variable region (TCR Vbeta and V alpha) repertoires in peripheral mononuclear cells were analyzed at the time of disease onset and at disease progression by the inverse PCR method. When a high usage (> 15%) of a specific Vbeta family member was observed, a clonal analysis was performed by PCR using beta-chain joining region (Jbeta) primers. The clonality of specific Vbeta-Jbeta fragments was confirmed by a single strand confirmation polymorphism (SSCP) analysis. RESULTS: Although there was no preferential usage of Vbeta in Patient 1, the exclusive expression of Jbeta1.2 for Vbeta13 was observed. A high frequency of Vbeta13 also was observed at the time of disease progression, but the Jbeta fragment for Vbeta13 was polyclonal. In Patient 2, the restricted usage of Jbeta1.6 for Vbeta5a was observed at the time of disease onset, whereas Jbeta1.1 and 1.2 for Vbeta4 were observed exclusively at the time of disease progression. The clonality of Vbeta13-Jbeta1.2 in Patient 1 and Vbeta5a-Jbeta1.6 and Vbeta4-Jbeta1.1/Jbeta1.2 in Patient 2 was confirmed by SSCP analysis. CONCLUSIONS: These findings suggest that the polyclonal T-cell lymphoproliferative disease associated with EBV was induced after BMT in Patient 1, and that the clonal change of expanded T-cells also was induced by EBV in Patient 2. The clonal analysis of T-cells is a useful tool to clarify the pathogenesis of FHL.     

Melanoma patients respond to a cytotoxic T lymphocyte-defined self-peptide with diverse and nonoverlapping T-cell receptor repertoires

HLA-A2+ melanoma patients develop naturally a strong CD8+ T cell response to a self-peptide derived from Melan-A. Here, we have used HLA-A2/peptide tetramers to isolate Melan-A-specific T cells from tumor-infiltrated lymph nodes of two HLA-A2+ melanoma patients and analyzed their TCR beta chain V segment and complementarity determining region 3 length and sequence. We found a broad diversity in Melan-A-specific immune T-cell receptor (TCR) repertoires in terms of both TCR beta chain variable gene segment usage and clonal composition. In addition, immune TCR repertoires selected in the patients were not overlapping. In contrast to previously characterized CD8+ T-cell responses to viral infections, this study provides evidence against usage of highly restricted TCR repertoire in the natural response to a self-differentiation tumor antigen.     

Human monoclonal antibodies reactive with human myelomonocytic leukemia cells

Peripheral blood mononuclear cells from a patient with chronic myelogenous leukemia (CML), in remission, were depleted of CD8-positive T-cells and cultured with Epstein-Barr virus. Four of 20 cultures (20%) secreted human IgG antibodies selectively reactive with the cell surfaces of certain human leukemia cell lines. Three polyclonal, Epstein-Barr virus-transformed, B-cell lines were expanded and fused with the human-mouse myeloma analogue HMMA2.11TG/O. Antibody from secreting clones HL 1.2 (IgG1), HL 2.1 (IgG3), and HL 3.1 (IgG1) have been characterized. All three react with HL-60 (promyelocytic), RWLeu4 (CML promyelocytic), and U937 (monocytic), but not with KG-1 (myeloblastic) or K562 (CML erythroid). There is no reactivity with T-cell lines, Burkitt's cell lines, pre-B-leukemia cell lines, or an undifferentiated CML cell line, BV173. Leukemic cells from two of seven patients with acute myelogenous leukemia and one of five with acute lymphocytic leukemia react with all three antibodies. Normal lymphocytes, monocytes, polymorphonuclear cells, red blood cells, bone marrow cells, and platelets do not react. Samples from patients with other diverse hematopoietic malignancies showed no reactivity. Immunoprecipitations suggest that the reactive antigen(s) is a lactoperoxidase iodinatable series of cell surface proteins with molecular weights of 42,000-54,000 and a noniodinatable protein with a molecular weight of 82,000. Based on these data these human monoclonal antibodies appear to react with myelomonocytic leukemic cells and may detect a leukemia-specific antigen or a highly restricted differentiation antigen.