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Group 2 innate lymphoid cells (ILC2s) play a critical role in protection against helminths and in diverse inflammatory diseases by responding to soluble factors such as the alarmin IL-33, that is often overexpressed in cancer. Nonetheless, regulatory factors that dictate ILC2 functions remain poorly studied. Here, we show that peroxisome proliferator-activated receptor gamma (PPARγ) is selectively expressed in ILC2s in humans and in mice, acting as a central functional regulator. Pharmacologic inhibition or genetic deletion of PPARγ in ILC2s significantly impair IL-33-induced Type-2 cytokine production and mitochondrial fitness. Further, PPARγ blockade in ILC2s disrupts their pro-tumoral effect induced by IL-33-secreting cancer cells. Lastly, genetic ablation of PPARγ in ILC2s significantly suppresses tumor growth in vivo. Our findings highlight a crucial role for PPARγ in supporting the IL-33 dependent pro-tumorigenic role of ILC2s and suggest that PPARγ can be considered as a druggable pathway in ILC2s to inhibit their effector functions. Hence, PPARγ targeting might be exploited in cancer immunotherapy and in other ILC2-driven mediated disorders, such as asthma and allergy.

Innate lymphoid cells (ILCs) represent the most recently identified subset of effector lymphocytes, with key roles in the orchestration of early immune responses. Despite their established involvement in the pathogenesis of many inflammatory disorders, the role of ILCs in cancer remains poorly defined. Here we assessed whether human ILCs can actively interact with the endothelium to promote tumor growth control, favoring immune cell adhesion. We show that, among all ILC subsets, ILCPs elicited the strongest upregulation of adhesion molecules in endothelial cells (ECs) in vitro, mainly in a contact-dependent manner through the tumor necrosis factor receptor- and RANK-dependent engagement of the NF-κB pathway. Moreover, the ILCP-mediated activation of the ECs resulted to be functional by fostering the adhesion of other innate and adaptive immune cells. Interestingly, pre-exposure of ILCPs to human tumor cell lines strongly impaired this capacity. Hence, the ILCP-EC interaction might represent an attractive target to regulate the immune cell trafficking to tumor sites and, therefore, the establishment of an anti-tumor immune response., Competing Interests: GV, GE, SC, MR, ML, LD, EM, PS, PR, CJ, ST No competing interests declared, (© 2021, Vanoni et al.)

Innate lymphoid cells (ILC) are a family of immune cells that are emerging as potent orchestrators of immune responses. In cancer, ILCs display both pro- and antitumorigenic functions depending on the nature of the tumor and the involved ILC subset. Little is known about the ILC-tumor cross-talk in human melanoma. Here, we showed that ILC1s were enriched but functionally impaired in cytokine secretion in both peripheral blood mononuclear cells and tumor-infiltrated lymph nodes of melanoma patients. These findings were confirmed in vivo in murine cutaneous melanoma. Multiple immunosuppressive mechanisms are described in the melanoma microenvironment. Among others, adenosine and kynurenines were shown to suppress antitumor immune responses. By exposing ILCs to adenosine and kynurenines, we observed a similar shift toward the ILC1 subset distribution and impairment in proinflammatory cytokine production to that of patient samples studied ex vivo . Thus, we hypothesized that the immunosuppressive microenvironment of malignant melanoma might shape ILC subpopulations. Hence, we provide a rationale for the use of drugs targeting adenosine and kynurenine pathways in melanoma patients., (©2020 American Association for Cancer Research.)

During the last 10 years, different subsets of Innate lymphoid cells (ILCs) have been identified in murine models. ILCs play and important role in maintaining immune barriers, tissue homeostasis, and are able to regulate the immune response in several anatomic sites. They can be found in lymphoid and non-lymphoid organs of adult mice but are mainly tissue-resident cells that can expand locally under physiologic or pathologic conditions (Gasteiger, Fan, Dikiy, Lee, & Rudensky, 2015). Because ILCs need to be identified by a complex combination of several cell-surface and intracellular markers and by their production of specific sets of cytokines, multiparametric flow cytometry remains one of the most efficient methods to analyze and isolate the different ILC sub-populations. This chapter describes how ILCs can be identified in different murine organs and how ILC subsets can be isolated and functionally analyzed., (© 2020 Elsevier Inc. All rights reserved.)

Several distinct innate lymphoid cell (ILC) populations have been recently identified and shown to play a critical role in the immediate immune defense. In the context of tumors, there is evidence to support a dual role for ILCs with pro- or antitumor effects, depending on the ILC subset and the type of cancer. This ambivalent role has been particularly well-described in colorectal cancer models (CRC), but the presence and the evolution of ILCs in the peripheral blood of metastatic CRC (mCRC) patients have not yet been explored. Here, we investigated the distribution of ILC subsets in 96 mCRC patients who were prospectively included in the "Epitopes-CRC02" trial. Peripheral blood mononuclear cells (PBMCs) were analyzed by flow cytometry at metastatic diagnosis and after 3-months of treatment. The treatments consisted of Oxaliplatin-based chemotherapies for 76% of the patients or Folfiri (5FU, Irinotecan) chemotherapies for 14% of patients. Compared to healthy donors, the frequency of total ILCs was dramatically increased at metastatic diagnosis. CD56 + ILC1-like cells were expanded, whereas ILC2, NCR - ILCP and NCR + ILCP subsets were decreased. Combined analysis with the systemic anti-telomerase hTERT Th1 CD4 response revealed that patients with low anti-TERT Th1 CD4 responses had the highest frequencies of total ILCs at diagnosis. Of those, 91% had synchronous metastases, and their median progression-free survival was 7.43 months (vs. 9.17 months for the other patients). In these patients, ILC1 and ILC2 were significantly decreased, whereas CD56 + ILC1-like cells were significantly increased compared to patients with low frequency of total ILCs and high anti-TERT responses. After treatment, the NCR + ILCP were further decreased irrespective of the chemotherapy regimen, whereas the balance between ILC1 and CD56 + ILC1-like cells was modulated mainly by the Folfiri regimen in favor of ILC1. Altogether our results describe the effects of different chemotherapies on ILCs in mCRC patients. We also establish for the first time a link between frequency of ILCs and anti-tumor CD4 T cell responses in cancer patients. Thus, our study supports an interest in monitoring ILCs during cancer therapy to possibly identify predictive biomarkers in mCRC.

Simple Summary: Lymphocytes expanded from benign prostate hypertrophy (BPH) tissue samples recognize tumor antigens and autologous tissue independently from the presence of tumor lesions. These data sustain the connection between BPH and prostate cancer and may pave the way to personalized preventive vaccination in patients with BPH. Benign prostate hyperplasia (BPH) is a frequent condition in aging men, which affects life quality, causing principally lower urinary tract symptoms. Epidemiologic studies suggest that BPH may raise the risk of developing prostate cancer (PCa), most likely promoting a chronic inflammatory environment. Studies aiming at elucidating the link and risk factors that connect BPH and PCa are urgently needed to develop prevention strategies. The BPH microenvironment, similar to the PCa one, increases immune infiltration of the prostate, but, in contrast to PCa, immunosuppression may not be established yet. In this study, we found that prostate-infiltrating lymphocytes (PILs) expanded from hyperplastic prostate tissue recognized tumor-associated antigens (TAA) and autologous tissue, regardless of the presence of tumor cells. PILs expanded from BPH samples of patients with PCa, however, seem to respond more strongly to autologous tissue. Phenotypic characterization of the infiltrating PILs revealed a trend towards better expanding CD4+ T cells in infiltrates derived from PCa, but no significant differences were found. These findings suggest that T cell tolerance is compromised in BPH-affected prostates, likely due to qualitative or quantitative alterations of the antigenic landscape. Our data support the hypothesis that BPH increases the risk of PCa and may pave the way for new personalized preventive vaccine strategies for these patients. [ABSTRACT FROM AUTHOR]

Soluble interleukin-6 receptor α subunit (sIL-6R) is primarily generated by shedding of the membrane-bound form. This process is influenced by the single nucleotide polymorphism rs8192284 (A > C) resulting in an aspartic acid to alanine substitution (D358A) at the proteolytic cleavage site. The aim of this study was to determine whether plasma levels of sIL6R are influenced by the rs8192284 polymorphism in patients with rheumatoid arthritis and to assess the association between plasma sIL-6R levels and disease activity as reflected by anti-CCP status. Thirty-nine patients were randomly selected from a cohort of patients with RA of Spanish descent. Plasma sIL-6R concentrations were measured using sandwich ELISA. Genotyping of the rs8192284 (A > C) polymorphism was done using a Fast Real-Time PCR System. DAS 28 scores were used to assess disease activity. Plasma sIL-6R levels were positively associated with the number of C alleles (AA: 35.27 (3.50) ng/ml, AC: 45.50 (4.58) ng/ml, CC: 52.55 (3.18) ng/ml, P = 0.0001). DAS28 and plasma sIL-6R levels were positively associated in the anti-CCP-positive subgroup ( r = 0.45, P = 0.0336) and negatively associated in the anti-CCP-negative subgroup ( r = −0.45, P = 0.0825). No association between anti-CCP status and sIL-6R level was found. Our findings show that the rs8192284 polymorphism is operative in patients with RA. The presence of anti-CCP antibodies determines the relationship between sIL-6R concentration and disease activity. [ABSTRACT FROM AUTHOR]

Background: The introduction of antibody markers to identify undesired cell populations in flow-cytometry based assays, so called DUMP channel markers, has become a practice in an increasing number of labs performing HLApeptide multimer assays. However, the impact of the introduction of a DUMP channel in multimer assays has so far not been systematically investigated across a broad variety of protocols. Methods: The Cancer Research Institute's Cancer Immunotherapy Consortium (CRI-CIC) conducted a multimer proficiency panel with a specific focus on the impact of DUMP channel use. The panel design allowed individual laboratories to use their own protocol for thawing, staining, gating, and data analysis. Each experiment was performed twice and in parallel, with and without the application of a dump channel strategy. Results: The introduction of a DUMP channel is an effective measure to reduce the amount of non-specific MULTIMER binding to T cells. Beneficial effects for the use of a DUMP channel were observed across a wide range of individual laboratories and for all tested donor-antigen combinations. In 48% of experiments we observed a reduction of the background MULTIMER-binding. In this subgroup of experiments the median background reduction observed after introduction of a DUMP channel was 0.053%. Conclusions: We conclude that appropriate use of a DUMP channel can significantly reduce background staining across a large fraction of protocols and improve the ability to accurately detect and quantify the frequency of antigen-specific T cells by multimer reagents. Thus, use of a DUMP channel may become crucial for detecting low frequency antigen-specific immune responses. Further recommendations on assay performance and data presentation guidelines for publication of MULTIMER experimental data are provided. [ABSTRACT FROM AUTHOR]

Background: The differentiation of CD8+T lymphocytes following priming of naïve cells is central in the establishment of the adaptive immune response. Yet, the molecular events underlying this process are not fully understood. MicroRNAs have been recently shown to play a key role in the regulation of haematopoiesis in mouse, but their implication in peripheral lymphocyte differentiation in humans remains largely unknown. Methods: In order to explore the potential implication of microRNAs in CD8+T cell differentiation in humans, microRNA expression profiles were analysed using microarrays and quantitative PCR in several human CD8+T cell subsets defining the major steps of the T cell differentiation pathway. Results: We found expression of a limited set of microRNAs, including the miR-17∼92 cluster. Moreover, we reveal the existence of differentiation-associated regulation of specific microRNAs. When compared to naive cells, miR-21 and miR-155 were indeed found upregulated upon differentiation to effector cells, while expression of the miR- 17∼92 cluster tended to concomitantly decrease. Conclusions: This study establishes for the first time in a large panel of individuals the existence of differentiation associated regulation of microRNA expression in human CD8+T lymphocytes in vivo, which is likely to impact on specific cellular functions. [ABSTRACT FROM AUTHOR]

γδ cells are implicated in host defense against microbes and tumors but their mode of function remains largely unresolved. Here, we have investigated the ability of activated human Vγ9Vδ2+ T cells (termed γδ T-APC5s to cross-present microbial and tumor antigens to CD8+ αβ T cells. Although this process is thought to be mediated best by DCs, adoptive transfer of ex vivo antigen-loaded, human DCs during immunotherapy of cancer patients has shown limited success. We report that γδ T-APCs take up and process soluble proteins and induce proliferation, target cell killing and cytokine production responses in antigen-experienced and naïve CD8+ αβ T cells. Induction of APC functions in Vγ9Vδ2+ T cells was accompanied by the up-regulation of costimulatory and MHC class I molecules. In contrast, the functional predominance of the immunoproteasome was a characteristic of γδ T cells irrespective of their state of activation. γδ T-APCs were more efficient in antigen cross-presentation than monocyte-derived DCs, which is in contrast to the strong induction of CD4+ αβ T cell responses by both types of APCs. Our study reveals unexpected properties of human γδ T-APCs in the induction of CD8+ αβ T effector cells, and justifies their further exploration in immunotherapy research. [ABSTRACT FROM AUTHOR]

Adoptive transfer therapy of in vitro-expanded tumor-specific cytolytic T lymphocytes (CTLs) can mediate objective cancer regression in patients. Yet, technical limitations hamper precise monitoring of post therapy T cell responses. Here we show in a mouse model that fused single photon emission computed tomography and x-ray computed tomography allows quantitative whole-body imaging of 111In-oxine-labeled CTLs at tumor sites. Assessment of CTL localization is rapid, noninvasive, three-dimensional, and can be repeated for longitudinal analyses. We compared the effects of lymphodepletion before adoptive transfer on (IL recruitment and report that combined treatment increased intratumoral delivery of CTL5 and improved antitumor efficacy. Because 111In-oxine is a Food and Drug Administration-approved clinical agent, and human SPECT-CT systems are available, this approach should be clinically translatable, insofar as it may assess the efficacy of immunization procedures in individual patients and lead to development of more effective therapies. [ABSTRACT FROM AUTHOR]

The cornerstone of the concept of immunosurveillance in cancer should be the experimental demonstration of immune responses able to alter the course of in vivo spontaneous tumor progression. Elegant genetic manipulation of the mouse immune system has proved this tenet. In parallel, progress in understanding human T cell mediated immunity has allowed to document the existence in cancer patients of naturally acquired T cell responses to molecularly defined tumor antigens. Various attributes of cutaneous melanoma tumors, notably their adaptability to in vitro tissue culture conditions, have contributed to convert this tumor in the prototype for studies of human antitumor immune responses. As a consequence, the first human cytolytic T lymphocyte (CTL)-defined tumor antigen and numerous others have been identified using lymphocyte material from patients bearing this tumor, detailed analyses of specific T cell responses have been reported and a relatively large number of clinical trials of vaccination have been performed in the last 15 years. Thus, the "melanoma model" continues to provide valuable insights to guide the development of clinically effective cancer therapies based on the recruitment of the immune system. This chapter reviews recent knowledge on human CD8 and CD4 T cell responses to melanoma antigens. [ABSTRACT FROM AUTHOR]

The role of antigen specific CD8+ T-lymphocytes in mediating protection against sporozoite-induced malaria has been well established in murine models. In humans, indirect evidence has accumulated suggesting a similar protective role for antigen-specific CD8+ T-lymphocytes. Nevertheless, the low frequency of circulating specific cells together with the lack of sensitive methods to quantify them has hampered the direct assessment of their function. Using a combination of short-term cell culture and IFN-γ ELISPOT, we studied CD8+ T-lymphocyte responses to a panel of HLA-A*0201 binding peptides. In addition to confirming the response to already described epitopes, we also identified five new CD8+ T-lymphocyte epitopes. These epitopes are presented in pre-erythrocytic stages gene products of Plasmodium falciparum 7G8 strain and correspond to the following protein segments: circumsporozoite (CS) 64-72, 104-113, 299-308 and 403-411; liver stage antigen (LSA-1) repeat region; sporozoite surface protein 2 or thrombospondin related anonymous protein (SSP2/TRAP) 78–88 and 504–513. Four of these peptides are conserved amongst all published sequences of P. falciparum strains. We conclude that the modified IFN-γ ELISPOT assay is a sensitive technique to monitor antigen-specific CD8+ T-lymphocyte responses in human malaria which may help in the improvement and assessment of the efficacy of malaria subunit vaccines. [ABSTRACT FROM AUTHOR]

Persistent viruses are kept in check by specific lymphocytes. The clonal T cell receptor (TCR) repertoire against Epstein-Barr virus (EBV), once established following primary infection, exhibits a robust stability over time. However, the determinants contributing to this long-term persistence are still poorly characterized. Taking advantage of an in vivo clinical setting where lymphocyte homeostasis was transiently perturbed, we studied EBV antigen-specific CD8 T cells before and after non-myeloablative lympho-depleting chemotherapy of melanoma patients. Despite more advanced T cell differentiation, patients T cells showed clonal composition comparable to healthy individuals, sharing a preference for TRBV20 and TRBV29 gene segment usage and several co-dominant public TCR clonotypes. Moreover, our data revealed the presence of relatively few dominant EBV antigen-specific T cell clonotypes, which mostly persisted following transient lympho-depletion (TLD) and lymphocyte recovery, likely related to absence of EBV reactivation and de novo T cell priming in these patients. Interestingly, persisting clonotypes frequently co-expressed memory/homing-associated genes (CD27, IL7R, EOMES, CD62L/SELL and CCR5) supporting the notion that they are particularly important for long-lasting CD8 T cell responses. Nevertheless, the clonal composition of EBV-specific CD8 T cells was preserved over time with the presence of the same dominant clonotypes after non-myeloablative chemotherapy. The observed clonotype persistence demonstrates high robustness of CD8 T cell homeostasis and reconstitution. [ABSTRACT FROM AUTHOR]

NK cells are critical for innate immunity-mediated protection. The main roles of NK cells rely on their cytotoxic functions or depend on the tuning of Th1 adaptive immunity by IFN-γ. However, the precise influence of inflammatory cytokines on NK cell and CD4 T lymphocyte interactions was never investigated. In this study, we provide evidence that IL-21, a cytokine produced during chronic inflammation or infectious diseases, promotes the differentiation of a specific subset of NK cells coexpressing CD86 and HLA-DR and lacking NKp44. More importantly, IL-21-propagated HLA-DR+ NK cells produce macrophage migration inhibitory factor and provide costimulatory signaling during naive CD4+ T cell priming inducing the differentiation of uncommitted central memory T cells. Central memory T cells expanded in the presence of HLA-DR+ NK cells are CXCR3+CCR62 CCR42CXCR52 and produce IL-2, as well as low levels of TNF-α. Costimulation of CD4+ T cells by HLA-DR+ NK cells prevents the acquisition of effector memory phenotype induced by IL-2. Moreover, we identified this population of NK HLA-DR+ macrophage migration inhibitory factor+ cells in inflammatory human appendix. Collectively, these results demonstrate a novel function for IL-21 in tuning NK and CD4+ T cell interactions promoting a specific expansion of central memory lymphocytes. [ABSTRACT FROM AUTHOR]

Nucleotide-binding oligomerization domain-like receptors (NLRs) are intracellular proteins involved in innate-driven inflammatory responses. The function of the family member NLR caspase recruitment domain containing protein 5 (NLRC5) remains a matter of debate, particularly with respect to NF-KB activation, type I IFN, and MHC I expression. To address the role of NLRC5, we generated Mrc5-deflcient mice (Nlrc5A/A). In this article we show that these animals exhibit slightly decreased CD8+ T cell percentages, a phenotype compatible with deregulated MHC I expression. Of interest, NLRCS ablation only mildly affected MHC I expression on APCs and, accordingly, Nlrc5A/A macrophages efficiently primed CD8+ T cells. In contrast, NLRC5 deficiency dramatically impaired basal expression of MHC I in T, NKT, and NK lymphocytes. NLRC5 was sufficient to induce MHC I expression in a human lymphoid cell line, requiring both caspase recruitment and LRR domains. Moreover, endogenous NLRC5 localized to the nucleus and occupied the proximal promoter region of H-2 genes. Consistent with downregulated MHC I expression, the elimination of NlrcSA/A lymphocytes by cytotoxic T cells was markedly reduced and, in addition, we observed low NLRC5 expression in several murine and human lymphoid-derived tumor cell lines. Hence, loss of NLRC5 expression represents an advantage for evading CD8+ T cell-mediated elimination by downmodulation of MHC I levels--a mechanism that may be exploited by transformed cells. Our data show that NLRC5 acts as a key transcriptional regulator of MHC I in lymphocytes and support an essential role for NLRs in directing not only innate but also adaptive immune responses. [ABSTRACT FROM AUTHOR]

Abstract: The study of natural T cell responses against pathogens or tumors, as well as the assessment of new immunotherapy strategies aimed at boosting these responses, requires increasingly precise ex vivo analysis of blood samples. For practical reasons, studies are often performed using purified PBMC samples, usually cryopreserved. Here, we report on FACS analyses of peripheral blood T cells, performed by direct antibody staining of non-purified total blood. For comparison, fresh PBMC, purified by Ficoll, were analysed. Our results show that the latter method can induce a bias in subpopulation distribution, in particular of CD8+ T cells, and sometimes lead to inaccurate measurement of antigen specific CD8+ T cell responses. Direct analysis of total blood can be applied to longitudinal immuno-monitoring of T cell-based therapy. While the need to purify and cryopreserve PBMC for subsequent studies is obvious, the use of whole blood has the advantage of providing unbiased results and only small amounts of blood are used. [Copyright &y& Elsevier]

The induction of potent CD8+ T cell responses by vaccines to fight microbes or tumors remains a major challenge, as many candidates for human vaccines have proved to be poorly immunogenic. Deoxycytidyl-deoxy- guanosin oligodeoxynucleotides (CpG ODNs) trigger Toll-like receptor 9, resulting in dendritic cell maturation that can enhance immunogenicity of peptide-based vaccines in mice. We tested whether a synthetic ODN, CpG 7909, could improve human tumor antigen-specific CD8+ T cell responses. Eight HLA-A2+ melanoma patients received 4 monthly vaccinations of low-dose CpG 7909 mixed with melanoma antigen A (Melan-A; identical to MART-i) analog peptide and incomplete Freund's adjuvant. All patients exhibited rapid and strong antigen- specific T cell responses: the frequency of Melan-A-specific T cells reached over 3% of circulating CD8+ T cells. This was one order of magnitude higher than the frequency seen in 8 control patients treated similarly but without CpG and 1-3 orders of magnitude higher than that seen in previous studies with synthetic vaccines. The enhanced T cell populations consisted primarily of effector memory cells, which in part secreted IFN-γ and expressed granzyme B and perform ex vivo. In vitro, T cell clones recognized and killed melanoma cells in an antigen-specific manner. Thus, CpG 7909 is an efficient vaccine adjuvant that promotes strong antigen- specific CD8+ T cell responses in humans. [ABSTRACT FROM AUTHOR]

Efficient immune attack of malignant disease requires the concerted action of both CD8+ CTL and CD4+ Th cells. We used human leukocyte antigen (HLA)-A*0201 (A2.1) transgenic mice, in which the mouse CD8 molecule cannot efficiently interact with the α3 domain of A2.1, to generate a high-affinity, CD8-independent T cell receptor (TCR) specific for a commonly expressed, tumor-associated cytotoxic T lymphocyte (CTL) epitope derived from the human p53 tumor suppressor protein. Retroviral expression of this CD8-independent, p53-specific TCR into human T cells imparted the CD8+ T lymphocytes with broad tumor-specific CTL activity and turned CD4+ T cells into potent tumor-reactive, p53A2.1-specific Th cells. Both T cell subsets were cooperative and interacted synergistically with dendritic cell intermediates and tumor targets. The intentional redirection of both CD4+ Th cells and CD8+ CTL by the same high-affinity, CD8-independent, tumor-specific TCR could provide the basis for novel broad-spectrum cancer immunotherapeutics. [Copyright &y& Elsevier]

Anti-melanoma cytolytic T-lymphocyte (CTL) clones were derived from peripheral blood lymphocytes of HLA-A2 melanoma patient LB265 after stimulation with the autologous tumor cell line LB265-MEL, which showed high expression of melanocyte-lineage specific genes. Of 55 CTL clones, 46 recognized HLA-A1-restricted antigens. These 46 CTL clones were studied for their ability to specifically release tumor necrosis factor in the presence of COS cells cotransfected with the HLA-A2 gene and the cDNA of either tyrosinase, Melan-A/MART1, Pmel17/gp100, gp75/TRP1, or MSH receptor. Six CTL clones recognized the Melan-A/MART1 antigen, whereas the remaining 40 CTL clones recognized a Pmel17/gp100 antigen. These 40 anti-Pmel17/gp100 CTL clones were all able to lyse T2 cells pulsed with the antigenic peptide YLEPGPVTA, as previously reported. The T-cell receptor β chain hypervariable region was sequenced and found to be identical in the 15 CTL clones analyzed. Taken together, these data show a high frequency of Pmel17/gp100-specific T cells in autologous antitumor CTL clones derived from peripheral blood of a melanoma patient. [ABSTRACT FROM AUTHOR]