A Correlation between the Expression of CD 8 Antigen and Specific Cytotoxicity of Tumor-infiltrating Lymphocytes

Tumor-infiltrating lymphocytes (TIL) from six gynecologic malignant tumors (two uterine cervical cancers, two ovarian serous cystadenocarcinomas, and two uterine corpus cancers), cultured in the presence of recombinant interleukin 2, were assayed for their cytotoxic activities against various fresh tumor cells including autologous tumors. A clear correlation between phenotype and cytotoxic activity of TIL was observed. Four of six TIL preparations exhibited strong cytotoxic activity against autologous fresh tumor target cells, and were all CD8^±. In contrast, cytotoxic activity was not detected in any of the CD4^± TIL preparations. The cytotoxic activities of the CD8^± TIL preparations were highly specific; only autologous fresh tumor cells were lysed. This result is consistent with the notion that TIL are of a different cell lineage from lympholdne-activated killer cells which are antigen-nonspecific and CD8^-. Instead, TIL appear to be of cytotoxic T cell lineage that is highly antigen-specific and CD8^±. To explore the potential for clinical use, we have attempted to augment the cytotoxic activities of these CD8^± TIL by treatment of the target tumor cells with gamma interferon (IFN) in vitro , hoping that elevated expression of MHC class I gene products on the cell surface would enhance their recognition. It was observed that brief treatment of freshly prepared tumor cells in vitro with gamma-IFN resulted in augmentation of the expression of MHC class I gene products, and the treated tumor cells were more susceptible to lysis by TIL than untreated cells.     

Clonal analysis of tumor-infiltrating lymphocytes from human primary and metastatic liver tumors

Phenotypic and functional characteristics of tumor-infiltrating lymphocytes (TIL) obtained from human primary and metastatic liver tumors were studied. Lymphocytes isolated from 18 tumors and autologous (A) peripheral blood (6 cases) were phenotyped by 2-color flow cytometry and cloned in a limiting dilution system, which allows virtually all normal T lymphocytes to proliferate; 70-80% of fresh TIL were T cells (i.e., CD3+), and the ratio of CD4+/CD8+ cells was 1.2 in both primary and metastatic liver tumors. TIL contained significantly more CD56+ (NKHI+) cells, half of which were CD3+CD56+, CD3+CD25+ cells and CD3+HLA-DR+ cells, than A-PBL. The frequencies of proliferating T-cell precursors (PTL-p) and cytolytic T-lymphocyte precursors (CTL-p) reactive with K562, allogeneic tumor cells and autologous tumor cells, were determined. Mean PTL-p frequencies for TIL from hepatocellular carcinomas, cholangiocarcinomas and metastatic liver tumors were 0.52 (0.22-0.83), 0.10 (0.05-0.16) and 0.16 (0.01-0.30), respectively. The frequency of CTL-p with natural-killer-like activity was lower in TIL than in A-PBL. The frequency of CTL-p for autologous tumor cells in fresh TIL isolated from primary liver tumors was 0.02-0.13 and 12/81 clones were reactive against autologous tumor. In contrast, only 1/66 TIL clones obtained from colon carcinomas metastatic to liver showed autotumor reactivity. No clones reactive with autologous tumor were obtained from peripheral blood of patients with liver cancer. These data indicate that substantial differences in anti-tumor functions of TIL between primary and metastatic liver tumors exist, which can be detected at a clonal level.     

Clinical application of adoptive immunotherapy by cytotoxic T lymphocytes induced from tumor-infiltrating lymphocytes

The tumor-infiltrating lymphocytes (TIL) were cultured with interleukin 2 (IL-2) to induce the cytotoxic T lymphocytes possessing autologous tumor-killing activity from 21 cancer patients (11 with solid tumor and 10 with malignant peritoneal or pleural effusions), and transferred into 7 patients as IL-2-activated TIL adoptively. The clinical application of activated TIL by adoptive transfer could result the complete regression of malignant pleural effusions in a patient with pancreatic cancer, and the nearly complete regression of malignant ascites in a patient with gastric cancer. The autologous tumor cells were isolated at the purity of more than 90% by Ficoll-Hypaque and Percoll discontinuous gradients, and then the TIL were cultured with IL-2 until 4 weeks. The optimal concentration of IL-2 was 1,500 IU/ml to obtain maximum proliferation and autologous tumor killing activity. The cytotoxic activities of activated TIL at 3 weeks-incubation was 72 +/- 15, 42 +/- 26, 27 +/- 21 and 22 +/- 15% against K562, Daudi, KATO-III and autologous tumor, respectively. By negative selection method, it was clarified that the killer cells recognizing autologous tumor consisted of CD4 or CD8 positive T lymphocyte in 43% of patients. The CD8 positive cells and CD56 positive cells increased, the CD4 positive cells and CD16 positive cells decreased by flow cytometry. The activated TIL could lyse not only cultured tumor cell lines, also other autologous tumor cells. The CD56+ cells were isolated by the Panning method, these cells could not lyse autologous tumor cells. Thus, it was indicated that the cytotoxic T lymphocytes recognizing autologous tumor could be generated from TIL and the adoptive immunotherapy of activated TIL was effective in cancer therapy.     

Solid-phase anti-CD3 antibody activation and cryopreservation of human tumor-infiltrating lymphocytes derived from epithelial ovarian cancer.

The effect of solid-phase anti-CD3 antibody activation and cryopreservation was evaluated on thirteen samples of tumor-infiltrating lymphocytes (TILs) derived from epithelial ovarian cancer. Seven preparations of TILs were cultured with or without solid-phase anti-CD3 antibody in addition to 100 units/ml of recombinant interleukin-2 (rIL-2). The proliferation rate of all of the seven TIL preparations stimulated by anti-CD3 antibody on the fourth or fifth day of culture was 3.4 to 9.8 times greater than that of lymphocytes cultured with rIL-2 alone. Furthermore, in an experiment with five TIL samples activated with anti-CD3 antibody, three of them showed augmented cytotoxic activity against autologous fresh tumor cells. The population of CD3+/CD8+ TILs was increased after 4-5 weeks of cultivation and CD8+ lymphocytes amounted to over 70% in all of seven preparations tested, whereas two of seven preparations not activated by anti-CD3 antibody were CD3+/CD4(+)-dominant. In addition, nine preparations of TILs cultured with rIL-2 were cryopreserved for several weeks; after recovery from cryopreservation, no major change was observed in cell surface markers, in growth rate or in cytotoxic activity. These results suggest that cryopreserved and/or anti-CD3 antibody-activated lymphocytes could conveniently be employed in a clinical trial of adoptive immunotherapy employing TIL.     

Peripheral blood and tumor infiltrating lymphocytes in non-small cell lung cancer: analysis at the population and clonal level

Tumor infiltrating (TIL) and peripheral blood lymphocytes (PBL) were isolated from 18 patients with non-small cell lung cancer undergoing radical surgery. Surface marker analysis revealed that TILs and PBLs mainly consisted of CD3+ T cells and that TILs generally displayed a lower CD4/CD8 ratio. Differences were found in the expression of CD25 (IL-2 receptor) and DR (MHC class II) antigens, which were increased in TILs, and in the percentage of CD16+ natural killer (NK) cells, which was reduced in TILs as compared to PBLs. Accordingly, the NK activity of TILs was lower than that of PBLs, whereas neither TILs nor PBLs expressed spontaneous cytolytic activity against fresh autologous tumor cells, melanoma cells and the "NK-resistant" A549 lung carcinoma cell line. After 4 days of culture in medium with recombinant-interleukin-2 (rIL-2), TILs and PBLs acquired cytolytic activity against all cell targets, but TILs expressed higher levels of cytotoxicity than autologous PBLs only in 3 patients out of 16 tested. More importantly, both TILs and PBLs displayed similar levels of cytotoxic activity against autologous tumor cells. TILs and PBLs from 8 patients were also analyzed by a limiting dilution microculture system. Cloning efficiency was remarkably lower in TILs, and surface marker analysis of T cell clones confirmed that an accumulation of CD8+ lymphocytes, which displayed cytolytic activity in a lectin-dependent assay, occurred at the tumor site. The non-MHC-restricted cytolytic activity of TIL- and PBL-derived T cell clones against K562, A549, and allogeneic melanoma cells and the cytolytic activity against autologous tumor cells showed no significant differences. Only 53% of TIL clones released IL-2 in response to PHA + TPA stimulation, whereas 68% of PBL-derived clones were IL-2 producers. Moreover, most PBL- and TIL-derived clones released tumor necrosis factor alpha in response to mitogen stimulation.     

Solid-phase Anti-CD3 Antibody Activation and Cryopreservation of Human Tumor-infiltrating Lymphocytes Derived from Epithelial Ovarian Cancer

The effect of solid-phase anti-CD3 antibody activation and cryopreservation was evaluated on thirteen samples of tumor-infiltrating lymphocytes (TILs) derived from epithelial ovarian cancer. Seven preparations of TILs were cultured with or without solid-phase anti-CD3 antibody in addition to 100 units/ml of recombinant interleukin-2 (rIL-2). The proliferation rate of all of the seven TIL preparations stimulated by anti-CD3 antibody on the fourth or fifth day of culture was 3.4 to 9.8 times greater than that of lymphocytes cultured with rIL-2 alone. Furthermore, in an experiment with five TIL samples activated with anti-CD3 antibody, three of them showed augmented cytotoxic activity against autologous fresh tumor cells. The population of CD3⁺/CD8⁺ TILs was increased after 4–5 weeks of cultivation and CD8⁺ lymphocytes amounted to over 70% in all of seven preparations tested, whereas two of seven preparations not activated by anti-CD3 antibody were CD3⁺/CD4⁺-dominant. In addition, nine preparations of TILs cultured with rIL-2 were cryopreserved for several weeks; after recovery from cryopreservation, no major change was observed in cell surface markers, in growth rate or in cytotoxic activity. These results suggest that cryopreserved and/or anti-CD3 antibody-activated lymphocytes could conveniently be employed in a clinical trial of adoptive immunotherapy employing TIL.     

Lymphocytes infiltrating human ovarian tumors: synergy between tumor necrosis factor alpha and interleukin 2 in the generation of CD8+ effectors from tumor-infiltrating lymphocytes

Tumor-infiltrating lymphocytes (TIL) were isolated by enzymatic digestion and gradient centrifugation from 18 human ovarian carcinomas. These cells were cultured in a complete medium supplemented with recombinant interleukin 2 (IL2) alone or recombinant IL2 plus recombinant tumor necrosis factor alpha (TNF-alpha), and their growth and antitumor cytotoxicity were determined. TIL cultured in the presence of IL2 plus TNF-alpha (1000 units/ml each) for 6 days showed significantly higher cytotoxicity against fresh autologous tumor targets than did TIL cultured with IL2 alone (e.g., mean lytic units/10(7) cells for 8 TIL preparations were 290 versus 74; P less than 0.05). No differences in [3H]thymidine uptake or natural killer cell activity were observed among these TIL cultures. In titration experiments, optimal synergistic concentrations of IL2 and TNF-alpha were determined as 10(2) and 10(3) units/ml, respectively. Using these concentrations for culturing the TIL, effector cells developed which preferentially lysed autologous tumor and displayed a CD8+ phenotype (up to 75% positive). However, the autologous tumor cytotoxicity mediated by these cultured TIL on day 6 was short lived. By day 12, it was replaced by non-major histocompatibility complex-restricted, lymphokine-activated killer cell-like activity mediated by CD3-CD56+ effector cells. Simultaneously, the production of gamma-interferon and interleukin 1 decreased in these cultures. In contrast to TNF-alpha, anti-CD3 antibody synergized with IL2 to increase 2-3-fold TIL proliferation but not their cytotoxic activity against autologous tumor cell targets. These data suggest that TNF-alpha and IL2 synergize early in culture to induce tumor-reactive CD8+ effectors, some of which may be specific for autologous ovarian tumor cells. However, the conditions needed to sustain the specific autologous tumor responses in long-term cultures of human TIL remain to be determined.     

TIL from renal-cell carcinoma: restimulation with tumor influences proliferation and cytolytic activity

TIL were cultured from human renal-cell carcinoma (RCC) in 1,000 U/ml rIL2 and restimulated with autologous tumor in efforts to establish which conditions would best expand the number of lymphocytes cytotoxic for autologous tumor. Greater cell yields resulted from multiple restimulations of TIL with autologous tumor. In most instances, these TIL lysed autologous tumor better than TIL grown in rIL2 alone. Enhanced proliferation was seen also after restimulation of TIL with allogeneic RCC as well as with tumor cells of non-renal origin. Although in some instances lysis of autologous tumor appeared to be specific, restimulation with autologous tumor did not consistently result in the generation of specific cytolytic T cells. Attempts to culture more specific cytolytic T cells by using 50 U/ml rIL2 were successful in expanding TIL with enhanced lytic activity; however, this activity was not specific for autologous tumor. The phenotype of the tumor-restimulated TIL generally did not change. In most of the TIL cultures, CD3+CD4+ cells were predominant with low numbers of CD3+Leu19+ cells and minimal numbers of CD3-Leu19+ cells. Thus, the cytotoxic response to tumor was mediated by T cells and not NK cells. Overall, our data indicate that restimulation of TIL with autologous tumor may be beneficial for growing larger numbers of cells which have increased lytic activity and for prolonging the presence of lytic activity among the expanded TIL.     

Interleukin-12 Augments the Generation of Autologous Tumor-reactive CD8+ Cytotoxic T Lymphocytes from Tumor-infiltrating Lymphocytes

Human tumor-infiltrating lymphocytes (TIL) were obtained from breast cancer, renal cancer or neuroblastoma to investigate the generation of autologous tumor-reactive CD8⁺ cytotoxic T lymphocytes (CTL). When TIL were cultured with interleukin (IL)-2 (100 U/ml), the growth of TIL peaked around 8–10 days after the initiation of culture. In contrast, the proliferation of TIL cultured with IL-2 plus IL-12 peaked around 4–5 days after culture and tumor cells rapidly disappeared from the culture. To determine the generation of autologous tumor-reactive CD8⁺ CTL, TIL-derived CD8⁺ T cells were separated by FACStar. Both IL-2-activated and IL-2 plus IL-12-activated TIL-CD8⁺ T cells showed the same level of lymphokine-activated killer activity against a variety of tumor cells. However, TIL-CD8⁺ T cells activated with IL-2 plus IL-12 revealed greatly augmented cytotoxicity against autologous tumor cells compared with that induced by IL-2 alone. The autologous tumor cell-killing activity of TIL-CD8⁺ CTL was significantly inhibited by the addition of F(ab)₂ anti-CD3 monoclonal antibody, indicating that these CTL recognize autologous tumor antigen through T cell receptor. These results imply that IL-12 is a novel cytokine which facilitates the generation of autologous tumor-reactive CD8⁺ CTL from TIL.     

Functional and phenotypic analysis of tumor-infiltrating lymphocytes isolated from human primary and metastatic liver tumors and cultured in recombinant interleukin-2

Tumor-infiltrating lymphocytes (TIL) were isolated from 40 of 51 consecutive human liver tumor samples (primary hepatocellular carcinoma, 16 of 18; metastatic, 23 of 29; benign, one of four). Functional and phenotypic characteristics of fresh and recombinant interleukin-2 (rIL-2)-expanded TIL were evaluated. The expansion of TIL from hepatic tumors in the presence of 1000 units/ml of rIL-2 was possible in 60% of cases. In comparison to TIL from metastatic liver tumors, TIL obtained from primary liver tumors expanded faster and better in rIL-2 cultures. Expanded TIL from primary tumors had significantly higher cytotoxicity against K562 targets, but not Raji targets, than those from metastatic tumors. Cytotoxicity against fresh autologous tumor targets was detected in seven of eight cultures tested. TIL from primary tumors retained antitumor reactivity significantly longer in culture. The optimal in vitro cytotoxicity was achieved between days 20 and 60 of culture in the presence of rIL-2. Antitumor activity was associated with the increase in these TIL cultures of a cell population expressing the Leu19 antigen with or without the CD3 antigen. The frequency of the CD3+Leu19+ population showed a bimodal distribution during culture: the first peak of CD3+Leu19+ cells occurred between days 30 and 60 and was associated with the increased antitumor activity; the second peak occurred after day 60 and was not associated with activity. These findings demonstrate that TIL from most human hepatic tumors can be successfully isolated, cultured in rIL-2, and enriched in Leu19+ effectors. In addition, these TIL upon IL-2 activation in vitro are capable of lysing fresh autologous and/or allogeneic tumor targets.     

Interleukin 2 activation of cytotoxic T-lymphocytes infiltrating into human metastatic melanomas

Tumor infiltrating lymphocytes (TIL) were isolated from 22 tumors obtained from 15 patients with metastatic melanoma. In 18 of the 22 tumors, a substantial number of lymphocytes was isolated with an average lymphoid cell:tumor cell ratio of 1.26. The TIL were predominantly cytotoxic/suppressor T-lymphocytes with an average of 87% Leu4+, 61% Leu2a+, and 18% Leu3a+ cells. There were less than 2% natural killer cells, B-cells, or macrophages. An average of 3.8% (range, less than 0.1 to 8.6%) of freshly isolated TIL bound to autologous tumor cells. Prior to culture, none of the tumor-binding cells (TBC) was cytotoxic as judged by trypan blue exclusion. The frequency of TBC increased to 11.6% after 2 days of culture, and 10% of these TBC developed cytotoxic activity. When interleukin 2 was added to cultures, the frequency of TBC increased, and the frequency of cytotoxic TBC was 2-fold higher compared to control cultures. After 10 days of culture with interleukin 2, TIL increased in number with a concomitant disappearance of tumor cells, whereas there were severe decreases of lymphocytes and no decrease of tumor cells in control cultures. TIL were cultured for 8 to 10 days with recombinant interleukin 2 and tested for cytotoxicity against autologous and allogenic tumor cells and K562 targets in a 4-h 51Cr release assay. rIL2-cultured TIL from all nine patients tested exhibited the highest levels of lysis against autologous tumor cells. Of the nine TIL samples, five exhibited an apparent specificity for autologous melanoma, while four specimens killed both allogenic and autologous melanoma. The ability of TIL to kill K562 targets appeared to parallel the ability to kill allogenic targets. For comparison, recombinant interleukin 2-cultured peripheral blood mononuclear cells from the same patients were assayed for cytotoxic activity against autologous and allogenic melanomas. Unlike some TIL, none of the peripheral blood mononuclear cells exhibited specificity for autologous tumor cells. In summary, TIL isolated from metastatic melanoma patients were predominantly cytotoxic T-lymphocytes with the ability to recognize and kill autologous tumor cells after in vitro culture; interleukin 2 induced proliferation of TIL and augmented their cytotoxic activity such that they eliminated autologous tumor cells.     

Interleukin 2 expanded tumor-infiltrating lymphocytes in human renal cell cancer: isolation, characterization, and antitumor activity

We have described a method for the generation, from fresh human renal cell cancers, of lymphoid cells that are capable of exhibiting significant antitumor reactivity when tested in short term 51Cr release assays. Tumor cell suspensions obtained from 37 consecutive fresh human renal cell cancer specimens (35 patients) could be separated by using enzymatic techniques and culturing in medium containing recombinant interleukin 2 (IL-2). The total cell recovery was 1.5 X 10(9) +/- 2.2 (SE) per tumor with a range of 1 X 10(8) to 5 X 10(9) cells. The percentage of tumor cells in the suspension ranged from 6 to 75% with a mean of 39.1 +/- 3.3%. The remaining cells were predominantly lymphocytes. Viability of mononuclear cells was greater than 90%. Activated tumor-infiltrating lymphocytes (TIL) within these tumors expand and by 10 to 14 days after initiation of culture a 5- to 15-fold increase in the number of lymphocytes could be achieved with elimination of all autologous tumor cells. Lymphocytes were recultured in fresh medium containing IL-2 and continued to expand between 2- and 10-fold every 4 to 6 days for an average of 33.7 +/- 4.5 days, resulting in greater than 50,000-fold increase in the total number of lymphocytes. The average number of splits was 4.9 +/- 0.8, with a range of 0 to 21. In 11 of 11 cases tested, TIL exhibited a far better expansion capability in vitro compared to that of peripheral blood lymphocytes obtained from the same patient and grown under identical conditions. The majority of TIL were T cytotoxic/suppressor cells (Leu 2+ Leu 4+). With continued in vitro expansion (up to 50 days) there was a concomitant increase in the helper T (Leu 3+) and pan T populations (Leu 4+) and decrease in Leu 2+ and HLA-DR+ cells. Compared with expanded peripheral blood lymphocytes, these cells demonstrated higher levels of IL-2+ receptors and HLA-DR+ antigens. Renal TIL effectors expanded in IL-2 could lyse almost all autologous tumor targets in 4-h chromium release assays. Allogeneic renal as well as nonrenal targets were equally lysed. TIL lysis of cultured tumor targets K562 and Daudi was significantly better than lysis of autologous, allogeneic-renal, and nonrenal targets. No statistically significant difference in the cytotoxic activity of renal TIL or peripheral blood lymphocyte effectors in killing autologous or allogeneic targets could be demonstrated.(ABSTRACT TRUNCATED AT 400 WORDS)     

Lymphokine-activated killer-cell function of lymphocytes from peripheral blood, regional lymph nodes and tumor tissues of patients with oral cancer

Lymphokine-activated killer (LAK) cells, generated from peripheral blood lymphocytes (PBL) from patients with oral cancer or oral leukoplakia and from healthy donors showed comparable lysis of 6 target tumor cell lines, including 3 derived from head and neck and oral cancers. The tumor burden of the host did not appear to influence the systemic LAK activity. LAK activity of lymphocytes infiltrating the tumor tissues (TIL) was also comparable to that of the PBL. Both TIL and PBL showed a parallel increase in proportion of HNK-I+ and CD-25+ cells upon activation with IL-2. The lymph-node lymphocytes (LNL) from metastatic (met) and non-metastatic (non-met) draining lymph nodes, however, showed reduced LAK activity and an increase in CD8+ cells, in addition to CD25+ and HNK-I+ cells, when cultured with IL-2. When IL-2-activated LNL were co-cultured with autologous PBL during IL-2 activation of the latter, a strong suppressive effect was exerted by LNL. In contrast, IL-2-activated PBL did not suppress autologous LAK generation in spite of an increase in CD8+ cells seen after activation with IL-2. Frequency distribution of LAK precursors was significantly lower in LNL than in PBL from oral cancer patients. LAK precursor frequency in TIL was comparable to that of PBL. The results show that, in oral cancer, regional lymph nodes may not have adequate IL-2-inducible cytotoxic potential, due to a reduced number of LAK progenitors and possible activation of suppressor cells. Alternatively, TIL can be a potential source for LAK cell function.     

MHC class I-restricted recognition of a melanoma antigen by a human CD4+ tumor infiltrating lymphocyte

It is generally considered that MHC class I-restricted antigens are recognized by CD8+ T cells, whereas MHC class II-restricted antigens are recognized by CD4+ T cells. In the present study, we report an MHC class I-restricted CD4+ T cell isolated from the tumor infiltrating lymphocytes (TILs) of a patient with metastatic melanoma. TIL 1383 I recognized HLA-A2+ melanoma cell lines but not autologous transformed B cells or fibroblasts. The antigen recognized by TIL 1383 I was tyrosinase, and the epitope was the 368-376 peptide. Antibody blocking assays confirmed that TIL 1383 I was MHC class I restricted, and the CD4 and CD8 coreceptors did not contribute significantly to antigen recognition. TIL 1383 I was weakly cytolytic and secreted cytokines in a pattern consistent with it being a Th1 cell. The avidity of TIL 1383 I for peptide pulsed targets is 10-100-fold lower than most melanoma-reactive CD8+ T cell clones. These CD4+ T cells may represent a relatively rare population of T cells that express a T-cell receptor capable of cross-reacting with an MHC class I/peptide complex with sufficient affinity to allow triggering in the absence of the CD4 coreceptor.     

Functional characterization of tumor-infiltrating lymphocytes, lymph-node lymphocytes and peripheral-blood lymphocytes from patients with breast cancer

Mononuclear cell infiltration is frequently seen within human solid tumors. Effector cells within the tumor site usually fail to exhibit cytotoxic or natural killer activity when freshly isolated; however, they develop potent and sometimes specific cytotoxicity after expansion in IL2. Thus, local tumor environment may influence lymphocyte function. In our study, we disaggregated human breast-cancer and lymph-node tissue to obtain lymphocyte-enriched cell fractions. Besides phenotypic analysis, functional characterization with regard to proliferation and cytokine production of tumor-infiltrating lymphocytes (TIL), peripheral-blood lymphocytes (PBL) and lymph-node lymphocytes (LNL) was the aim of our study. TIL showed an enrichment of CD8+ cells with a corresponding decrease in CD4+ cells in comparison with PBL and LNL. In response to PHA, TIL showed decreased 3H-thymidine uptake, but TIL were significantly stimulated by rhIL2. TIL produced low levels of IL2, TNF and IFN gamma upon mitogen/phorbol ester stimulation, while PBL produce high levels of TNF and IFN gamma but low levels of IL2. Under the same experimental conditions, LNL produce high levels of TNF and IL2 but low levels of IFN gamma. Mitogen-mediated TNF secretion was increased after addition of autologous tumor cells in TIL and LNL, whereas IFN gamma secretion tended to be suppressed. Our results indicate different patterns of activities of TIL, LNL and PBL from breast-cancer patients.     

Characterization of the cytolytic activity of CD4+ and CD8+ tumor-infiltrating lymphocytes in human renal cell carcinoma

Previously we showed that IL2 expanded tumor-infiltrating lymphocytes (TILs) from renal cell carcinoma mediated non-major histocompatibility complex-restricted cytotoxicity. Phenotypic analysis showed that cultured TILs were composed mostly of T-lymphocytes with varying numbers of CD4+, CD8+, and CD56+ (Leu19+) populations. Here we compared the cytolytic activity of the two predominant TIL subsets, CD3+CD4+ and CD3+CD8+, to that of the CD56+ populations. Using magnetic beads coated with antibodies to either CD4 or CD8, CD3+CD4+, and CD3+CD8+ TILs were isolated in a highly enriched form (greater than 92%) and could be expanded for over 40 days in vitro with 1000 units/ml IL2. In a 4-h 51Cr release assay the CD4+ and CD8+ TILs showed minimal lytic activity, whereas unseparated cells exhibited significant levels of non-major histocompatibility complex-restricted cytotoxicity. The lytic activity seen in the 4-h assay with unseparated TILs appeared to be related to the presence of CD56+ populations. With one exception none of the purified CD4+ or CD8+ TILs expressed any significant levels of CD56, while the unseparated TILs contained varying numbers of CD3+CD56+ and CD3-CD56+ populations. Cell-sorting experiments verified that the CD56+ populations were responsible for most of the lytic activity in 4 h even though CD3+CD56- cells represented the predominant cell type. Although CD3+CD56- TILs were minimally lytic in 4 h, we show here that both CD3+CD4+ and CD3+CD8+ subsets displayed substantial cytotoxicity in long-term assays. In the 18-h 51Cr release assay 5 of 6 CD4+ and 2 of 3 CD8+ TILs were lytic for the autologous tumor. In two cases, restimulation with the autologous tumor induced augmented cytolytic activity of TIL subsets and in one case induced lytic activity in 4 h. The cytotoxic activity of TIL subsets was further examined using a 72-h assay in which TILs were cocultured with a confluent layer of tumor cells. The degree of cytotoxicity was quantitated by measuring the amount of crystal violet dye that was incorporated by tumor cells which remained after the incubation period. CD4+ and CD8+ TILs typically caused greater than a 50% reduction of tumor cells in 3 days and the level of reduction was increased when IL2 was added to the cultures. All the CD4+ and CD8+ subset preparations were cytotoxic in the 3-day assay even though some were not lytic for certain targets in the 18-h 51Cr release assay.(ABSTRACT TRUNCATED AT 400 WORDS)     

Clonal analysis of lymphocytes from tumor, peripheral blood, and nontumorous kidney in primary renal cell carcinoma

The immunological properties of lymphocytes from tumor, peripheral blood (PBL), and nontumorous kidney from 16 patients with renal cell carcinoma were characterized at the clonal level with respect to their clonogenic efficiency, phenotypic expression, and cytotoxicity against autologous and allogenic tumor cells. The objectives were to delineate: (a) the quantitative differences in the immunological properties of tumor-infiltrating lymphocytes (TIL) from patient to patient; and (b) the qualitative differences in immunological properties between TIL and lymphocytes from peripheral blood or nontumorous kidney from a single patient. A total of 926 clones were characterized for phenotype expression, and 465 clones were characterized for cytotoxicity. The clonogenic efficiency of TIL varied with individuals: high in one patient; relatively high to moderate in seven patients; low in seven patients, and extremely low in the remaining one patient. The levels of autologous tumor cell lysis by TIL clones also varied with individuals. More than one-third of the TIL clones established in 4 of 13 patients displayed significant (greater than or equal to 10%) lysis against autologous tumor cells, and in each of the four patients the average percentage of lysis in the total TIL clones was higher than 10%. In two patients, 5 of 26 or 3 of 13 TIL clones were cytotoxic, but averages of percentage of lysis in the total clones were less than 10%. One 1 or 2 TIL clones of 10-27 total clones were cytotoxic in each of 4 patients, while no cytotoxic TIL clones were found in the remaining 3 patients. Clonogenic efficiency did not correlate with the level of cytotoxicity, and TIL from no tumors displayed both high proliferation and high cytotoxicity at the clonal level. In a majority of patients (12 of 13), most cytotoxic TIL clones against autologous tumor cells also lysed allogenic tumor cells. In contrast, TIL clones lysed only autologous tumor cells in the remaining one patient (patient 2). The clonogenic efficiency of TIL was lower than that of PBL in 6 of 12 patients, while the opposite was true in the remaining 6 patients. The level of cytotoxicity in the PBL clones of these 12 patients primarily correlated with that of the TIL clones. With one exception (patient 2), most cytotoxic PBL clones against autologous tumor cells also lysed allogenic targets in a majority of patients. CD4+CD8-T-cell clones (70-85%) predominated in all patients regardless of the different lymphocyte sources.(ABSTRACT TRUNCATED AT 400 WORDS)     

Human cytotoxic T cells specific for autologous melanoma cells: successful generation from lymph node cells in seven consecutive cases

Human T-cell populations specifically cytotoxic for autologous melanoma cells have been successfully generated from lymph node cells obtained from seven consecutive patients. The lymph node cells were stimulated in vitro with autologous irradiated melanoma cells; stimulation was repeated every 10-15 days at a tumor cell-to-lymphocyte ratio of approximately 1:20. Cytotoxic activity was assessed by a 4-hour 51Cr release assay. Mean lysis of autologous tumor cells was 47% at an effector-to-target cell ratio of 20:1, while mean lyses of the human myeloid leukemia cell line K562, allogeneic melanoma cells, and an osteosarcoma cell were 20%, 13%, and 11%, respectively. There was no lysis of autologous fibroblasts, fresh lymphocytes, or phytohemagglutinin-stimulated blasts. Three grades of specificity developed sequentially. In grade I, lysis of autologous tumor cells exceeded lysis of allogeneic tumor cells but did not exceed lysis of K562 cells. In grade II, lysis of autologous tumor cells exceeded lysis of K562 cells and all allogeneic tumor cells tested. In grade III, potent lysis of autologous tumor cells (greater than 40%) exceeded lysis of K562 cells and of all allogeneic tumor cells tested. All seven lymphocyte populations reached or exceeded grade I. Six reached or exceeded grade II. Two progressed to grade III. The generated cells were T cells, as determined by phenotypic analysis with flow cytometry. CD4+ cells and CD8+ cells accounted for 83%-100% of the cells. CD8+ T cells were separated from CD4+ T cells by panning with OKT8 and OKT4 antibodies. The resulting CD8-enriched and CD4-enriched populations were compared as effectors in cytotoxicity assays. The results suggest that the cell responsible for lysis of autologous tumor cells is CD8+. The methods used in this study have repeatedly resulted in the successful generation of cytotoxic T lymphocytes specifically cytotoxic for autologous melanoma cells; it is suggested that these cells have potential application for adoptive immunotherapy of melanoma.     

Immunotherapy of bovine ocular squamous cell carcinoma: isolation, culture and characterization of lymphocytes present in the tumor

Bovine ocular squamous cell carcinoma (BOSCC) is sensitive to intralesional immunotherapy with BCG or recombinant human IL-2 (rhIL-2). The mechanism of tumor regression is as yet unclear. Alterations in the concentration of IL-2 (and possibly other factors) in the tumor, due to regional injection or induction by BCG, may induce killer cell activity and thus tumor regression. To investigate this, lymphocytes were isolated by mechanical fractionation of biopsies of BOSCC. Growth, phenotypical, and functional characteristics were studied. TIL could be isolated and grown from all biopsies of BOSCC. An estimated increase in cell number of 50-150 fold was observed during 5-7 weeks of culture. FACS analysis of a limited number of the TIL cultures showed a characteristic shift in phenotypes until day 28 of culture. CD2+ cells (50-70%), and as a consequence of this CD2- cells, remained stable in number. The number of CD8+ cells increased. CD4+ cells were detected in low numbers by day 28. Prolonged culture resulted in an increase of CD2- gamma delta + cells, CD2+4-8- cells, and occasionally of both CD8+ and CD2+ cells. In 51Cr release assays TIL showed cytotoxicity for BOSCC-derived tumor cell lines in general, which increased transiently by cocultivation with tumor cells. Killing of YAC-1, and P815 was far less efficient. Preferential killing of autologous cell lines was not seen. In conclusion, TIL from bovine ocular squamous cell carcinomas can be cultured in the presence of rhIL-2, which induces cytotoxic activity for BOSCC-derived tumor cells. Cells responsible for killing in vitro and potentially for regression of the tumor after immunotherapy with BCG or rhIL2 cannot yet be identified. Depletion and blocking experiments are being conducted in order to identify the cells (CD2+8+, CD2-gamma delta + or other CD2 +/-) responsible for killing.