Antitumor activity of regional lymph node lymphocytes in patients with lung cancer

Successful induction of tumor-specific cytotoxic T lymphocytes from patients with non-small cell lung cancer using CD80-transfected autologous tumor cells

Cytotoxic T lymphocytes (CTL) against human lung cancer cells are difficult to induce by a conventional method using tumor cell stimulation probably due to an insufficiency of tumor antigens (TA) or costimulatory molecules such as CD80. We, therefore, investigated the potential of CD80-transfected tumor cells as stimulators of the in vitro induction of autologous tumor-specific CTL from regional lymph node lymphocytes in patients with lung cancer. Five non-small cell lung cancer cell lines (two adenocarcinomas, 1 squamous cell carcinoma, 1 large cell carcinoma and 1 adenosquamous cell carcinoma) were established from surgical specimens and were successfully transduced with a plasmid constructed with expression vector pBj and human CD80 cDNA, using a lipofection method. CD80-transfected tumor cells (CD80-AT) significantly augmented the proliferation of autologous lymphocytes from all cases as compared with non-transfected tumor cells (AT). AT-stimulated lymphocytes from 4 out of 5 cases did not show any cytotoxicity against AT; however, lymphocytes stimulated with CD80-AT exhibited substantial cytotoxicity against parental AT in all 5 cases tested. AT-stimulated lymphocytes derived from only one out of 5 cases showed major histocompatibility complex (MHC)-class I-restricted cytokine production in response to AT, while the MHC-class I-restricted responses were found in CD80-AT-stimulated lymphocytes from 4 out of 5 cases. These results indicate that CD80 on tumor cells could be a beneficial costimulatory molecule to elicit CTL against lung cancer, and also show that TA recognized by CTL was frequently expressed on lung cancer cells.

Expression of activation-related molecules on regional lymph node lymphocytes in human lung cancer

Using two- and three-color flow cytometry, we investigated the surface makers of regional lymph node lymphocytes (RLNL) in 54 patients with primary lung cancer in order to determine whether or not RLNL are in an activation state when compared with the corresponding peripheral blood lymphocytes (PBL) for the purpose of clarifying the characteristics of RLNL. RLNL showed a cell composition that was different from the corresponding PBL with a high proportion of CD3+ cells, CD4+ cells and CD20+ (B) cells as well as a low proportion of CD8+ cells and CD16+ (NK) cells. RLNL also contained a significantly higher proportion of CD45RO+ T cells and a lower proportion of CD45RA+ T cells in comparison to the corresponding PBL. Furthermore, we explored the activation-related molecules such as the interleukin-2 receptor (IL-2R) alpha chain, the IL-2R beta chain, HLA-DR and leukocyte function-associated antigen 1 (LFA-1) on CD4+ and CD8+ cells. The data showed that the expression of CD45RO, the IL-2R alpha chain, HLA-DR on CD4+ cells, and those of CD45RO and HLA-DR on CD8+ cells were significantly higher in RLNL than in PBL. On the other hand, PBL showed a higher expression of the IL-2R beta chain and LFA-1 only on CD8+ cells, which are thought to include CD8+ NK cells. When these activation related molecules were analyzed on CD45RO+ T cells, which are thought to be memory T cells, then the expression of the IL-2R alpha chain, HLA-DR on CD4+CD45RO+ cells and HLA-DR on CD8+CD45RO+ cells were significantly higher in RLNL than in PBL. Lastly, we analyzed the surface molecules according to such clinical factors as metastasis to the lymph nodes and the stage of lung cancer. Interestingly, RLNL with lymph node metastasis showed an increase in the percentage of CD20+ cells and a decrease in the percentage of CD4+ cells in comparison to those with benign lung disease, while these differences were not observed in PBL. The expression of ++CD45RO and LFA-1 on CD4+ and LFA-1 on CD8+ cells on RLNL in stage I + II is significantly higher in comparison with benign lung disease. Furthermore, RLNL in stage III + IV revealed the reduced expression of CD45RO, HLA-DR and LFA-1 on both CD4+ and CD8+ cells compared with those in stage I + II. These results thus demonstrated that RLNL were in a more activated state, particularly in stages I + II, than PBL. Whether these activation states in RLNL are directed against autologous tumor cells or not can hopefully be elucidated after the completion of further ongoing studies.

An attempt to generate an antitumor effect in the regional lymph nodes against endometrial cancer cells by inducing antitumor cytokines

Phytohemagglutinin-stimulated regional lymph node cells obtained from gynecological cancer patients exerted a significant antiproliferative activity against an endometrial cancer cell line, RL95-2 on a human tumor clonogenic assay, and released a high amount of tumor necrosis factor alpha (TNF alpha), and interferons. The activity was thought to be partly due to released TNF alpha, because RL95-2 was highly sensitive to recombinant TNF alpha. However, anti-TNF alpha failed to inhibit the activity, which indicated the probability of some as yet unclarified participation of cytokines. Therefore, the regional lymph nodes might be used as sites of endogenous cytokine therapy in endometrial cancer patients.

Clinical management of the regional lymph node

Appropriate clinical management of the regional lymph node remains controversial. This article briefly reviews the anatomy and physiology of the lymphatic system, pathophysiology of lymphatic metastases, and some guidelines and rationale for clinical management.

Augmentation of antitumor immunity in regional lymph nodes by local immunotherapy

We have previously reported that the antitumor effect of OK-432, a streptococcal preparation, is markedly augmented when injected intratumorally together with fibrinogen (OK-432/fbg) [1]. In order to elucidate the effects of this immunotherapy on regional lymph nodes (RLN), we carried out both morphological and functional analyses of the RLN from colonic cancer patients treated with OK-432/fbg. Computer-aided morphometry revealed that the maximal cross-sectional areas and the broadest diameters of the RLN were significantly greater (p < 0.01) in patients who had undergone local immunotherapy than in patients who had not. The component structures of RLN, such as sinus, follicle and paracortex, were all enlarged in the OK-432/fbg-treated patients, and necrosis of metastatic tumors was observed. RLN lymphocytes recovered from OK-432/fbg treated patients showed elevated reactivity to phytohemagglutinin (PHA) and the stimulation index was clearly higher than that of control patients. Flow cytometric analysis revealed a predominance of T-cells, especially CD4 subsets, and higher positivity for both CD25 and HLA-DR. Furthermore, RLN lymphocytes killed more effectively K562 and Daudi cells in the patients who had had immunotherapy. These results suggest that the effect of local immunotherapy with OK-432/fbg is not restricted to the site of injection but extends to the lymph nodes, and contributes to tumor regression through the augmentation of cellular immunity.

Potential of human lymph node cells for antitumor activity mediated by interferon gamma

The soluble antitumor activity of regional lymph node cells obtained from patients with cervical cancer was investigated by using a human tumor clonogenic assay (HTCA). A significant antiproliferative activity of the lymph node cells (LNCs) against a cervical cancer cell line, HeLa cells, was demonstrated by stimulation with either phytohemagglutinin (PHA) or concanavalin A (Con A), but not with interleukin-2 (IL-2). This antiproliferative activity of LNC was found in nonadherent cells, possibly T-cells. By using neutralizing antibody experiments, this activity was found to be attributed to interferon gamma (IFN gamma), but not to tumor necrosis factor (TNF), although both cytokines were produced from LNC. These results indicate that human LNC was able to exert an antiproliferative activity mediated through the cytokines by appropriate stimulation.

Studies of serum-free medium for the generation of lymphokine-activated killer cells

We examined a serum-free medium (designated as TYI 101) for the generation of lymphokine-activated killer (LAK) cells from human lymphocytes, regional lymph node lymphocytes (RLNL) and peripheral blood lymphocytes (PBL). TYI 101 medium consisted of, in addition to nutrient mixture, transferrin, insulin, fetuin, sodium selenite, 2-mercaptoethanol, o-phosphorylethanolamine, chick egg yolk and porcine kidney extract. These hormones were effective for supporting RLNL proliferation as assessed by (3H)-thymidine uptake. When human lymphocytes from two different sources were cultivated with recombinant interleukin 2 (rIL-2) in TYI 101 medium, LAK activity was generated. In cultures of PBL from a healthy donor, LAK cells were generated in TYI 101 medium as efficiently as in RPMI 1640 medium supplemented with 10% human AB-type serum (RPMI-AB). In cultures of RLNL from lung cancer patients, LAK activity obtained in TYI 101 medium was about sixty-five percent of that in RPMI-AB. However, the addition of a small amount of AB-type serum improved the generation of LAK activity, LAK cell expansion, and cell viability in TYI 101 medium. We conclude that TYI 101 medium can be used for the generation of LAK cells from human lymph node lymphocytes with supplementation of none or only a reduced amount of human serum.

Phenotypic characterization of lymphokine-activated killer cells from human lymph node lymphocytes

We previously reported that lymphokine-activated killer (LAK) activity can be generated in human lymph node lymphocytes (LNL) at the same level as that in peripheral blood lymphocytes (PBL), despite the absence of active natural killer (NK) cells. In the present study, we investigated the surface phenotype of LNL-LAK cells by fractionation of lymphocytes, using a panning method. LNL isolated from lung cancer patients were cultured in the presence of recombinant interleukin 2 for 8 days and separated into T cells and non-T cells according to the expression of CD3 antigen. LAK effectors were enriched in the CD3- non-T cells. However, the CD3+ cells also mediated a low but substantial level of LAK activity, which was attributed to a CD8+ T-cell subset. Further investigation of the CD3- cells revealed that most of the CD3- effector cells expressed neither B-cell (CD20) nor NK-cell (CD16) markers. Precursors of this CD3-CD20-CD16- (null) population appeared to be also CD3-, CD20-, and CD16-. From these results, we would stress the significant contribution of CD3-CD20-CD16- null cells to the LAK phenomenon, which has not been focused on in PBL.

Generation and expansion of lymphokine-activated killer cells from lymph node lymphocytes in human lung cancer

We cultured lymph node lymphocytes (LNL) from lung cancer patients in the presence of recombinant interleukin 2 (rIL2). The ability of LNL to respond to rIL2 was not affected by the advance of cancer stage when tested for proliferation and for lymphokine-activated killer (LAK) activity. The LAK activity of LNL was comparable to that of the corresponding peripheral blood lymphocytes. The rIL2-induced proliferation of macrophage-depleted LNL was augmented by the reconstitution with autologous alveolar macrophages while the LAK activity was not affected. However, macrophage-reconstituted LNL expanded rapidly and reached higher cell densities and exhibited a significantly lower LAK activity than macrophage-depleted LNL. The diminished LAK activity in macrophage-reconstituted LNL were markedly augmented by the subculture at a low cell density. From these results, we conclude that LNL can be a good material for the postoperative LAK therapy and that macrophage is useful in culture of LAK cells.