Effects of cytokines on in vitro growth of tumor-infiltrating lymphocytes obtained from human primary and metastatic liver tumors

Comparative phenotypes of peripheral blood and spleen cells from cancer patients

Patients with resectable tumor, either in the body or the tail of the pancreas, and cancer patients with a primary tumor adjacent to the splenic vasculature frequently undergo a splenectomy as standard of care during resection. The spleen provides an unutilized source of lymphocytes with potential utility for adoptive cellular therapy (ACT). In this report, spleen and peripheral blood (PB) cells from cancer patients were compared to one another and normal PB by flow cytometry with a focus on CD8⁺ T-cells, memory phenotype, and their relative expression of checkpoint proteins including program death ligand-1 (PD1). PD1 is both an activation marker for T-cells including antigen (Ag) specific responses, as well as a marker of T-cell exhaustion associated with co-expression of other checkpoint molecules such as lymphocyte activating gene-3 (LAG-3) and T-cell immunoglobulin and mucin domain containing-3 (TIM-3). In summary, the spleen is a rich source of CD8⁺PD1⁺ T-cells, with an 8-fold higher frequency compared to the PB. These CD8+ T-cells are predominantly central and transitional memory T-cells with associated effector phenotypes and low expression of TIM-3 and LAG-3 with potential utility for ACT".

Potential immunotherapeutic role of interleukin-2 and interleukin-12 combination in patients with hepatocellular carcinoma

Background

Many recent therapeutic interventions are necessary to improve the treatment of hepatocellular carcinoma (HCC), including immunotherapy, which seems to offer one of the new realistic therapeutic modalities. This study aims to investigate the optimization of immunotherapy for HCC patients by appraisal of both interferon (IFN)-γ levels and phenotyping of lymphocytes obtained from peripheral blood and fine-needle aspirates.

Methods

The isolated lymphocytes were cultured in the presence of interleukins (IL)-2, IL-4, and IL-12. Enzyme-linked immunosorbent assay and flow cytometric techniques were used for the assessment of human IFN-γ production and the studied T-cell subpopulations, respectively.

Results

Mixed cell populations of peripheral blood lymphocytes and tumor infiltrating lymphocytes treated with IL-2 plus IL-12 showed a marked and significant elevation in IFN-γ levels in their culture media, a significant decrease in the percentage of cluster of differentiation (CD)4⁺CD25⁺ regulatory T-cells, and a nonsignificant increase in the percentage of CD8⁺ cytotoxic T-cells. Meanwhile, IL-2 plus IL-4 treatment demonstrated nonsignificant effects.

Conclusion

Our data suggested that IL-12 together with IL-2 caused a suppression of CD4⁺CD25⁺ regulatory T-cells and an elevation of IFN-γ levels, which play a crucial immunotherapeutic role in the management of HCC patients.

Phenotype and function of T cells infiltrating visceral metastases from gastrointestinal cancers and melanoma: implications for adoptive cell transfer therapy

Adoptive cell transfer of tumor-infiltrating lymphocytes (TILs) can mediate cancer regression in patients with metastatic melanoma, but whether this approach can be applied to common epithelial malignancies remains unclear. In this study, we compared the phenotype and function of TILs derived from liver and lung metastases from patients with gastrointestinal (GI) cancers (n = 14) or melanoma (n = 42). Fewer CD3(+) T cells were found to infiltrate GI compared with melanoma metastases, but the proportions of CD8(+) cells, T cell differentiation stage, and expression of costimulatory molecules were similar for both tumor types. Clinical-scale expansion up to ~50 × 10(9) T cells on average was obtained for all patients with GI cancer and melanoma. From GI tumors, however, TIL outgrowth in high-dose IL-2 yielded 22 ± 1.4% CD3(+)CD8(+) cells compared with 63 ± 2.4% from melanoma (p < 0.001). IFN-γ ELISA demonstrated MHC class I-mediated reactivity of TIL against autologous tumor in 5 of 7 GI cancer patients tested (9% of 188 distinct TIL cultures) and in 9 of 10 melanoma patients (43% of 246 distinct TIL cultures). In these assays, MHC class I-mediated up-regulation of CD137 (4-1BB) expression on CD8(+) cells suggested that 0-3% of TILs expanded from GI cancer metastases were tumor-reactive. This study implies that the main challenge to the development of TIL adoptive cell transfer for metastatic GI cancers may not be the in vitro expansion of bulk TILs, but the ability to select and enrich for tumor-reactive T cells.

The role of cytokines in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a frequent malignancy worldwide with a high rate of metastasis. The hepatitis B and C viruses are considered major etiological factors associated with the development of HCC, particularly as a result of their induction of chronic inflammation. There is increasing evidence that the inflammatory process is inherently associated with many different cancer types, including HCC. Specifically, this review aims to cover evidence for the potential roles of cytokines, an important component of the immune system, in promoting HCC carcinogenesis and progression. A global summary of cytokine levels, functions, polymorphisms, and therapies with regard to HCC is presented. In particular, the role of proinflammatory Th1 and anti-inflammatory Th2 cytokine imbalances in the microenvironment of HCC patients with metastasis and the possible clinical significance of these findings are addressed. Overall, multiple studies, spanning many decades, have begun to elucidate the important role of cytokines in HCC.

Cholangiocarcinoma of the extrahepatic bile ducts

Malignancies of the biliary tree, particularly the extrahepatic bile ducts, remain difficult clinical problems. Because experience with these uncommon tumors has been limited to a small number of centers, meaningful clinical trials have been difficult to perform. Complete resection remains the most effective therapy, but is usually possible in the minority of patients. Palliating the effects of biliary obstruction is thus often the primary therapeutic goal. Chemotherapy and radiation therapy have not been proven to reduce the incidence of recurrence after resection nor to improve survival in patients with unresectable disease. This review focuses on cholangiocarcinoma of the extrahepatic bile ducts.

Clinicopathological study on hepatocellular carcinoma with lymphocytic infiltration

We examined the clinicopathologic features of 11 surgically resected hepatocellular carcinomas (HCCs) less than 3 cm in diameter with marked inflammatory cell infiltration (LHCCs). In comparison with the other 152 HCCs without such an infiltration (controls), there were no significant differences in male/female ratio, age, serum alpha-fetoprotein levels, and laboratory and imaging findings. All the 11 LHCC cases were hepatitis B surface antigen (HBsAg) negative and hepatitis C virus antibody positive. Among the 152 controls, 116 cases were also HBsAg negative and HCVAb positive and were referred to as HCV-only controls. The clinical features were not significantly different between the LHCC and the HCV-only controls. The LHCC group tended to have higher numbers of lymphocytes and monocytes in pre- and post-operative peripheral blood, but there were no significant group differences. Recurrence rate was 9.1% in the LHCC group, 47.7% in the controls and 47.5% in the HCV-only controls (P < .01). Five-year survival rate was 100% in the LHCC group, 65.1% in the controls and 68.1% in the HCV-only controls (P < .01). Histologically, remarkable inflammatory cell infiltration, mostly lymphocytic, was observed in the cancerous tissue of the LHCC group. Varying degrees of piecemeal necrosis of cancer nests produced by infiltrating lymphocytes were observed in all the 11 cases. Lymph follicle formation was also found in 10 of 11 cases (90.9%). Liver cirrhosis was associated in 6 LHCC cases (54.5%), in 117 control cases (77.0%), and in 91 HCV-only controls (78.4%). Tumor invasion into the portal vein in the vicinity of the tumor was found in 1 LHCC case (9.1%), in 54 controls (35.5%), and in 34 HCV-only controls (29.3%). Immunohistochemically, most of the infiltrating lymphocytes, other than those in the lymph follicle, were identified as T lymphocyte, and CD8+ T lymphocyte was more predominant than CD4+ T lymphocyte. Better prognosis of the LHCC group could attribute to the anti-tumor effect induced by cellular immunity of CD8+ and CD4+ T lymphocytes, and partly by humoral immunity of B cells which formed lymph follicles.

CD4+ hepatic cancer-specific cytotoxic T lymphocytes in patients with hepatocellular carcinoma

We investigated T cell immunity against hepatocellular carcinoma (HCC), and showed that both peripheral blood mononuclear cells and tumor-infiltrating lymphocytes incubated with interleukin-2 alone displayed HLA-nonrestricted but hepatic cancer-specific cytotoxicity in a majority of patients with HCC. Namely, they lysed both HCC and cholangiocellular carcinomas in an HLA-nonrestricted manner, but they did not lyse any tumors with the other histological types tested, normal hepatocytes, or the cells transfected with hepatitis C virus or MUC1 gene. These CTL lines and clones were phenotypically CD3+CD4+CD8-. These unique CTL could play important roles in T cell immunity against HCC.

Augmented antitumor effects of killer cells induced by tumor necrosis factor gene-transduced autologous tumor cells from gastrointestinal cancer patients

The purpose of this study was to determine the feasibility of a vaccine therapy using tumor necrosis factor (TNF) gene-transduced autologous tumor cells for the treatment of human gastrointestinal cancers, which tend to have lower immunogenicity than other cancers such as melanoma and renal cell carcinoma. We succeeded in establishing primary cultured tumor cells from 12/54 carcinomatous effusions (4 liver cancer patients, 5 gastric cancer patients, 1 pancreatic cancer patient, and 2 colon cancer patients) and in transducing the TNF gene to the tumor cells by using the retrovirus vector MFG-TNF. Even after irradiation, TNF production (0.3-3.5 U/ml per 10(6) cells per 72 hr) was confirmed for 10 of 12 transfectants, and the other two transduced cells were found to have approximately one TNF gene copy. In 7 of the 12 patients, the cytotoxic activity of killer cells to nontransduced autologous tumor cells incubated with these TNF gene transfectants was augmented. This activity was blocked with anti-HLA class I antibody or BrefeldinA (BFA), suggesting that the killer cells were cytotoxic T lymphocytes (CTL) and tumor antigens are presented with HLA class I molecules. Indeed, enhanced expression of HLA class I and/or ICAM-1 molecules on the surface of the TNF gene-transduced tumor cells were observed by fluorescence-activated cell sorting (FACS) analysis. Furthermore, natural killer (NK) and/or lymphokine-activated killer (LAK) activities determined by using K562 or Daudi cells as targets were also enhanced in some of these cases when they were incubated with TNF gene-transduced tumor cells. These findings indicate the feasibility of using TNF gene-transduced tumor cells as a vaccine in gastrointestinal cancer patients.

Culture of tumour-infiltrating lymphocytes from melanoma and colon carcinoma: removal of tumour cells does not affect tumour-specificity

The therapeutic potential of adoptive therapy using tumour-infiltrating lymphocytes (TIL) has been demonstrated in a number of clinical trials. However, freshly isolated tumour-infiltrating lymphocytes (TIL) are often impaired in their proliferative and cytotoxic responses, which limits their use in immunotherapy. Several hypotheses with regard to the poor effector function of TIL have been postulated, including the production of immunosuppressive factors by tumour cells. In a previous paper we reported the efficient expansion of immunoreactive TIL from a variety of solid tumours by stimulation with a combination of monoclonal antibodies (mAbs) against CD3 and CD28. In the present study we analysed whether this protocol would be improved by the removal of tumour cells at the start of the culture. We tested a highly immunogenic tumour, melanoma, and a poorly immunogenic tumour, colon carcinoma. Removal of tumour cells highly improved anti-CD3/CD28 stimulated expansion of TIL from colon carcinoma, resulting in a significantly higher percentage of potentially tumour-specific CD8-positive T-cells and a reduced CD4/CD8 ratio compared to expansion in the presence of tumour cells. In contrast, expansion and CD4/CD8 ratio of melanoma-derived TIL was not significantly influenced by the removal of autologous tumour cells. CD3/CD28-stimulated melanoma TIL cultured in the absence of tumour cells showed specific lysis of autologous tumour cells comparable to melanoma TIL cultured in high-dose IL2. However, no cytotoxicity could be detected in colon TIL irrespective of the culture conditions used. On the other hand, 3/8 colon carcinoma TIL cultures and 9/12 melanoma-derived TIL cultures showed IFN gamma secretion upon stimulation with autologous tumour cells. We conclude that stimulation of TIL with a combination of mAbs to CD3 and CD28 in the absence of tumour cells induces efficient expansion of potentially tumour-specific cells from a highly and a poorly immunogenic tumour. Removal of tumour cells does not have a negative influence on the generation of tumour-specific T cells, while cell yield improves. Therefore, for large-scale cultures this protocol can efficiently induce the outgrowth of tumour-specific TIL, at the same time providing a useful source of autologous tumour cells that can be stored and used to direct or test antitumour specificity.

Serum concentration of intercellular adhesion molecule-1 in patients with hepatocellular carcinoma is a marker of the disease progression and prognosis

Serum levels of soluble forms of intracellular adhesion molecule-1 (sICAM-1) and lymphocyte function-associated antigen-3 (sLFA-3) in 122 patients with chronic liver disease including hepatocellular carcinoma (HCC) were measured by enzyme-linked immunosorbent assays. Serum levels of sICAM-1 in patients with HCC were significantly higher than those of chronic hepatitis (CH) and cirrhosis. On the other hand, serum levels of sLFA-3 in patients with HCC were almost the same as those of cirrhosis. Western blot analyses showed that molecular sizes of sICAM-1 and sLFA-3 detected in the sera were 90 kd and 50 kd, respectively, indicating that both molecules include whole extracellular domains. In patients with HCC, circulating sICAM-1 levels were significantly (P < .001) correlated with tumor volume (r = .50), total bilirubin (r = .38), serum aspartate aminotransferase levels (r = .51), and gamma-globulin (r = .63). Furthermore, serum sICAM-1 levels were significantly elevated in patients with multiple HCC (tumor number > 3) or HCC with tumor embolus in the first branch or trunk of portal vein. Survival periods were analyzed in relation to serum sICAM-1 levels in patients with HCC who had been treated by transcatheter arterial chemoembolization. The HCC patients with < 1,000 ng/mL of serum ICAM-1 showed significantly (P = .0005) longer survival than those with higher levels of the molecule. The same results were obtained when only patients with moderately differentiated HCC were analyzed (P = .02). Analyses by Cox's proportional hazard model showed that sICAM-1 is a significant (P = .032) prognostic factor for patients with HCC.(ABSTRACT TRUNCATED AT 250 WORDS)

Tumour-infiltrating lymphocytes bear the 75 kDa tumour necrosis factor receptor

Tumour necrosis factor alpha (TNF-alpha) is a cytokine with a variety of immunological properties. The identification of two receptors for this molecule, i.e. the 75 kDa and the 55 kDa TNF receptors (TNF-R), recently clarified the mechanisms through which this cytokine provides its wide range of immunomodulatory activities. In this study we have investigated the expression and the functional properties of these receptors on tumour-infiltrating lymphocytes (TILs) recovered from 17 patients with solid cancers (melanoma, colorectal carcinoma and lung cancer). To this end, TIL lines and freshly isolated TILs were evaluated for (a) the expression and the functional role of TNF receptors following culture in the presence of interleukin 2 (IL-2) and (b) the production of TNF-alpha following culture with IL-2 and the role of this cytokine in IL-2-driven TIL proliferation. Flow cytometry analysis demonstrated that TILs bear the 75 kDa TNF-R. Moreover, TIL lines express detectable messages for TNF-alpha and release this cytokine. Functional in vitro studies have shown that anti-TNF-alpha, as well as anti-75 kDa TNF-R antibodies, are able to inhibit the IL-2-induced TIL proliferation. These data demonstrate that TILs are equipped with a fully functional TNF-R system and suggest a putative role for this receptor and its ligand in the activation and expression of TILs following immunotherapy with IL-2.

Antibodies to tumor necrosis factor: a component of B cell immune responses with a role in tumor/host interaction

Infiltrating B lymphocytes are found within tumors, where their role and the antigens they recognize are poorly defined. After in vitro expansion of these cells, we were able to detect the production of antibodies to tumor necrosis factor alpha (TNF) in 13 of 17 human tumors studied. These antibodies were detected by both enzyme-linked immunosorbent assay and by neutralization. Anti-TNF antibodies were not produced by resting peripheral blood B cells of normal subjects. However, anti-TNF antibodies were produced by B cells obtained from healthy individuals, after either in vivo or in vitro antigenic stimulation. This suggests that anti-TNF antibody production may constitute part of the overall B cell response to antigens. The intratumoral production of anti-TNF antibody may play a role in tumor/host interactions.

Interleukin 1 beta synergises with interleukin 2 in the outgrowth of autologous tumour-reactive CD8+ effectors

Using peritoneal fluid or pleural effusion obtained from 20 patients with lung, ovarian or metastatic breast cancer, we separated tumour cells from malignant effusion-associated mononuclear cells (MEMNCs) using discontinuous Ficoll-Hypaque density gradients. CD3+ T lymphocytes represented the main population of MEMNCs. The mean +/- s.d. CD4/CD8 ratio of MEMNC suspensions was 1.18 +/- 0.40. MEMNCs proliferated and expanded in vitro with human interleukin 2 (IL-2) either as CD3+ CD8+ cells or as CD3+ CD4+ cells or as mixed populations of CD8+ and CD4+ cells. Preferential cytolytic activity against autologous tumour cells was demonstrated in IL-2-activated MEMNC cultures with excess CD3+ CD8+ cells. In contrast, effectors derived from IL-2-activated cultures with excess CD3+ CD4+ cells lysed both autologous and allogeneic tumour target cells. The addition on day 0 of interleukin 1 beta (IL-1 beta) to MEMNCs cultured in the presence of IL-2 was effective in promoting the growth of CD3+ CD8+ cells and augmenting the cytotoxicity against autologous tumour. Simultaneously, the production of gamma-interferon (IFN-gamma) was increased in these cultures. This is the first report suggesting that IL-1 beta synergises with IL-2 to induce autologous tumour-specific CD8+ cytotoxic T lymphocytes (CTLs) within the MEMNC population. Selective enrichment in T-cell subsets by IL-1 beta may be useful in cellular adoptive immunotherapy using cells isolated from malignant effusions.

Functional role of IL-2 receptors on tumour-infiltrating lymphocytes

This study was undertaken to investigate the pathways involved in the interleukin 2 (IL-2)-driven growth of tumour-infiltrating lymphocytes (TILs). For this purpose, TIL lines and freshly isolated TILs obtained from 16 patients with solid cancer (three melanoma, seven primary colorectal carcinoma, four hepatic metastases from colorectal cancer and two lung cancer) were evaluated for (a) expression of IL-2 receptor (IL-2R) both at the RNA level and on the cell surface by flow cytometric analysis and (b) their proliferative activity in response to IL-2 and the role of IL-2R subunits in the IL-2-driven TIL growth. Northern blot analysis showed that TILs express a strong message for both the p55 and the p75 IL-2R. Accordingly, flow cytometric analysis demonstrated that TILs bear both IL-2R chains. TILs cultured in vitro in the presence of rIL-2 were able to proliferate in response to different concentrations of this cytokine. Monoclonal antibodies (MAbs) specifically recognising the p55 and p75 IL-2R chains (anti-Tac and TU27 respectively) exhibited a marked inhibitory effect on IL-2-driven growth when added individually or in appropriate combinations. Our results demonstrated that TILs are equipped with a fully functional IL-2 receptor system, thus suggesting the involvement of this structure in the activation and expansion of TILs following immunotherapy with IL-2.

Analysis of T cell receptor variability in fresh tumor-infiltrating lymphocytes from human head and neck cancer

In this study, we analyzed T cell receptor (TCR) gene rearrangements in tumor-infiltrating lymphocytes (TIL) freshly obtained from 15 patients with head and neck cancer using the reversely transcribed polymerase chain reaction (RT-PCR) method. These TILs showed preferential expression of V alpha 10, V alpha 8 and V alpha 1, detected in 13 (87%), 11 (73%), and 9 cases (60%), respectively. The TCRV beta gene revealed diversity without preferential usage. The head and neck region is exposed to bacteria and viruses, so it is possible that the tumor site can become infected and accumulate T cells involved in infection and inflammation. Therefore, we also investigated TCR gene usage in T cells infiltrating in chronic sinusitis mucosa to address the question of whether the V alpha 1, V alpha 8, and V alpha 10 subfamilies are characteristic in TIL from squamous cell carcinoma of head and neck. TCR V alpha 10 gene usage was also the most common in V alpha segment in T cells infiltrating the sinus mucosa, but V alpha 1 and V alpha 8 were not detected in the T cells in sinusitis. These results indicate that the V alpha 10 subfamily, the preferred T cell population in both TIL and T cells in inflammatory disease, might be involved mainly in inflammation or infection. On the other hand, V alpha 1 and V alpha 8 appear to be relatively specific populations for antitumor immunity in head and neck cancer.

The induction of murine tumor infiltrating lymphocytes (TIL) by interleukin-2 or T cell growth factor

Mice were injected in the foot pad with either 5 x 10(5) syngeneic plasmacytoma (MOPC104E) or fibrosarcoma cells (Meth A). Lymph nodes containing tumor cells were harvested 14 days later and cultured. In the presence of recombinant interleukin-2 (r-IL-2) predominantly tumor cells proliferated. Culture with T cell growth factor (TCGF) resulted in the growth of lymphoid cells. Concanavalin A (Con A) had only a modest effect on elimination of tumor cells in the culture. Tumor-infiltrating lymphocytes (TIL) prepared from the lymph nodes showed specific tumor-neutralizing activity when grown in the presence of TCGF. In vitro examination revealed that Meth A cells could not be lysed by TIL, while TIL from MOPC tumors showed tumor specific activity. This study may explain negative results in human trials with TIL induced by IL-2 alone.

Usage of T-cell receptor V beta chain genes in fresh and cultured tumor-infiltrating lymphocytes from human melanoma

Tumor-infiltrating lymphocytes (TIL) freshly obtained from human malignant melanomas as well as the same TIL grown in the presence of interleukin 2 (IL2) were studied for gene expression of the T-cell receptor (TCR) variable beta regions (V beta). To perform the TCR-V beta analysis, total RNA was isolated from TIL and reverse-transcribed into cDNA, which was then amplified by PCR using 22 different 5' primers specifically recognizing the sequences of 20 V beta gene families and a 3' primer annealing to the constant region of the beta chain. The TCR-alpha constant region (C alpha) gene was co-amplified as a standard for the calculation of the percentage of each TCR-V beta gene expressed. The frequency of individual V beta regions expressed on TIL was computed from the ratio of cpm V beta to cpm C alpha for each V beta region in relation to the total of all 22 ratios. With fresh TIL obtained from 8 different melanomas, oligoclonal distribution of V beta genes expressed on TIL was observed, in comparison with a broader and unrestricted distribution seen with peripheral-blood T cells of 8 normal individuals. The oligoclonal patterns of V beta-gene expression in fresh melanoma TIL were distinct in every tumor. Several of the V beta-genes usually expressed in normal PBL were not expressed in fresh TIL in melanoma TIL cultured in the presence of IL2 and IL4 and in the absence of autologous tumor (AuTu) or antigen-presenting cells for 23 to 65 days, selection of T-cell lines expressing a restricted number of V beta genes occurred. Although in 4/5 TIL cultures this selection involved the V beta 7 gene, no relationship could be established between V beta gene expression in fresh TIL and that in T-cell lines outgrowing in long-term cultures. Selection in culture of CD3+CD8+ T-cell lines with V beta-gene expression restricted to 1 or 2 V beta families did not correlate with the presence or level of AuTu cytotoxicity mediated by these T cells. The results indicate that in TIL cultures random selection of T-cell lines with reactivity not relevant to AuTu may account for poor expression or loss of AuTu cytotoxicity by most TIL cultured long-term in the presence of cytokines and in the absence of specific antigenic stimulation.

Autologous tumour-specific cytotoxic T-cell clone established from tumour-infiltrating lymphocytes (TIL) of malignant ascites in the absence of recombinant interleukin 2(rIL2): activation by autologous tumour cell alone

Mixtures of tumour infiltrating lymphocytes (TIL) and tumour cells collected from malignant ascites of a patient with pancreatic cancer were cultured using a microplate without recombinant interleukin 2(rIL2). TIL rapidly proliferated from 21-51 days after the initiation of culture in 20 out of 30 wells tested. Cytotoxicity was examined in 5 out of the 20 TIL-growing wells. One CD8+ TIL (well-1) displayed autologous tumour-specific cytotoxicity. Repeated stimulation with autologous tumour cells, in the absence of rIL2, was required for further propagation in long-term (60 days) culture of TIL. Four clones were established from well-1 by limiting dilution without rIL2. Surface phenotypes of the 4 clones were the same as those of well-1, i.e., CD8+, CD16-, CD25+, HLA-DR+. And autologous tumour cells were required for continuous proliferation of these CD8+ T-cell clones. Both well-1 and the 4 clones displayed similar degrees of cytotoxicity restricted to autologous tumour cells. These results indicate that TIL from malignant ascites may contain precursor cytotoxic T-lymphocytes (CTL) sensitized in vivo to autologous tumour cells, and that TIL are able to grow for several weeks or more with substantial increases in cell numbers in the absence of rIL2.

Specific immune recognition of autologous tumor by lymphocytes infiltrating colon carcinomas: analysis by cytokine secretion

Tumor-infiltrating lymphocytes (TIL) were grown in the presence of interleukin-2 from 19 colon carcinoma specimens, including 1 primary lesion and 18 metastatic lesions. These cultures showed a median proliferation of 606-fold (range 13-fold to 28,000-fold) over 49 culture days (range 26-76 days). By phenotype, mature cultures were 69%-99% CD3+ (mean 93%) and contained mixed populations of CD4+ and CD8+ cells (CD4 > CD8 in 10 of 19 cultures). Fresh cryopreserved colon tumors were not lysed by autologous TIL in short-term 51Cr-release assays, and were poorly lysed by lymphokine-activated killer cells. Ten TIL cultures were assayed for cytokine secretion in response to autologous and allogeneic tumors during a 6- to 24-h coincubation. Culture supernatants were tested by ELISA for the presence of granulocyte/macrophage-colony-stimulating factor, interferon gamma, and tumor necrosis factor alpha. Of 10 TIL, 4 secreted at least two of these cytokines specifically in response to autologous and/or HLA-matched fresh allogeneic colon carcinomas, but not to melanomas or HLA-unmatched colon carcinomas. Cytokine secretion was mediated by both CD4+ and CD8+ TIL, and could be inhibited by mAb directed against the appropriate class of MHC antigen. These data provide evidence for specific, MHC-restricted immune recognition of human colon carcinomas by T lymphocytes.

Gamma-interferon enhances the cytotoxic activity of interleukin-2-induced peripheral blood lymphocyte (LAK) cells, tumor infiltrating lymphocytes (TIL), and effusion associated lymphocytes

The effect of gamma-interferon (IFN-gamma) on the induction of interleukin-2 (IL-2) activated killer cell activity was studied: (I) in peripheral blood lymphocytes (LAK cells) from cancer patients and healthy donors, (II) in lymphocytes infiltrating solid tumors (TIL) from melanoma and breast cancer patients, and (III) in pleural effusion associated lymphocytes (EAL) from patients with lung adenocarcinoma. The coculture of LAK, TIL and pleural effusion mononuclear cells (MNC) with several doses of IFN-gamma (10, 50, 250, and 1250 U/ml) and a low dose of IL-2 (10 U/ml) for 5 days resulted in a synergistic effect on the cytotoxicity of these cells against several tumor cell lines. Furthermore there was a potentiation in the proliferation of MNC after a 5-day culture. The induction of lymphocyte cytotoxicity by a combination of IFN-gamma with low doses of IL-2 may be helpful in designing more effective cancer immunotherapeutic protocols with LAK, TIL or EAL.

Memory T-lymphocytes are the main population of tumor-infiltrating lymphocytes obtained from human primary liver tumors

The phenotypic characteristics of freshly isolated tumor-infiltrating lymphocytes (TIL) obtained from human liver tumors were analyzed by two-color flow cytometry. TIL consisted of mainly CD3+ T-lymphocytes (70-80%). The ratio of CD4/CD8 in TIL from primary and metastatic liver tumors and autologous peripheral blood lymphocytes (A-PBL) was 1.3, 1.1 and 1.3, respectively. The majority of CD3+ T-lymphocytes (mean +/- SD; 95 +/- 11%) expressed T-cell antigen receptor (TCR) alpha/beta, and gamma/delta TCR positive T-cells were only 5 +/- 4.5% in TIL from both primary and metastatic liver tumors. TIL showed significantly higher percentages of transient activation markers, such as CD25 (Tac) and HLA-DR, than A-PBL. TIL also contained significantly more populations of CD3+ CD45RO+ T-lymphocytes, which are considered to be expressed on primed (memory) T-lymphocytes, than A-PBL. Furthermore, TIL from primary liver tumors demonstrated significantly higher percentages of CD3+ CD45RO+ T-cells than those from metastatic liver tumors. These data indicate that TIL from human liver tumors are an apparently distinct population from A-PBL, and that local immune responses against human primary and metastatic liver tumors might be different. Moreover, TIL from primary liver tumors consisted of mainly activated or primed (memory) T-cells, suggesting that they were sensitized and activated by autologous tumor cells in vivo. These observations may imply the possibility of adoptive immunotherapy using TIL against human primary liver tumors.

A phase I study of local treatment of liver metastases with recombinant tumour necrosis factor

15 patients with therapy-resistant liver metastases were treated in a phase I study with recombinant tumour necrosis factor (rTNF). rTNF was injected into a liver metastasis by ultrasound guidance, using a 50 micrograms escalating dose schedule (3 patients/dosage) ranging from 100 to 350 micrograms per injection. Influenza-like symptoms such as fever, chills, nausea and vomiting were the main clinical side-effects. 2 patients experienced transient hypotension, probably due to concomitant use of morphine. Other toxicities, as reported after systemic use of rTNF, such as decrease in leucocytes and platelet counts, renal or liver toxicity were not observed. No difference was seen in subpopulations of lymphocytes (CD3+, CD4+, CD8+, CD16+ and CD19+) prior to and after rTNF injection. In 8 patients stable disease occurred in rTNF-treated metastases. The maximal dose used by this route of administration is 350 micrograms per injection. Based on these observations we conclude that the toxicity of rTNF injected into liver metastases by sonographic control is transient and mild. The results suggest that intratumoral administration of rTNF might play a role in local tumour control.

Phenotypic and functional analysis of lymphocytes infiltrating paediatric tumours, with a characterization of the tumour phenotype

Tumour-infiltrating lymphocytes (TIL) of paediatric tumours obtained from 37 lesions of different histotype (12 osteosarcomas, 5 Wilms' tumours, 7 soft-tissue sarcomas, 5 neuroblastomas and 8 miscellaneous) were studied to establish their potential for therapy. Fresh isolated TIL were cultured for the first 2 weeks with low doses of interleukin-2 (IL-2) (20 Cetus U/ml) to select for "tumour-specific" lymphocytes potentially present in the neoplastic lesion, followed by culture with high doses of IL-2 (1000 Cetus U/ml) to achieve TIL expansion. TIL were grown with more than 10-fold expansion in only 9 cases (mean expansion: 58-fold, range 13.5-346). In 17 cases no viable cells were obtained. After 30 days of culture with IL-2 the proliferative ability of TIL declined sharply in the majority of cases and TIL became refractory to any further stimulus, including addition of IL-4, tumour necrosis factor alpha (TNF alpha) or interferon gamma, and activation with OKT3 in solid phase. In 20 out of 37 cases TIL were available for phenotypic and functional analysis. TIL after long-term culture were predominantly CD3+ but 2 cases of osteosarcoma showed a predominance of CD3+TcR gamma/delta cells. The CD4/CD8 ratio was more than 1 in 10 cases, without correlation with tumour histology, site of lesion or TIL growth. The number of CD16+ and CD25+ lymphocytes decreased progressively during culture, the latter concomitantly with a reduction of TIL growth rate. The lytic pattern of TIL against allogenic and autologous tumour (Auto-Tu) cells was variable, but specific lysis of Auto-Tu was seen in only one case (Wilms' tumour) after culture with TNF alpha and irradiated Auto-Tu cells. The immunohistochemical analysis of tumour lesions revealed a limited lymphocyte infiltrate, a low expression of histocompatibility leukocyte antigens (HLA) class I and of the adhesion molecules ICAM1, LFA3, and a significant production of transforming growth factor beta (TGF beta). These data indicate that TIL obtained from paediatric patients are difficult to expand at levels required for immunotherapy and lack a significant number of tumour-specific T lymphocytes. A low expression of immunomodulatory molecules on tumour cells or the production of suppressive factors may prevent activation and expansion of TIL in paediatric tumours.