Suppressor cell function in solid tumor cancer patients

Impact of the immune cell population in peripheral blood on response and survival in patients receiving neoadjuvant chemotherapy for advanced gastric cancer

We aimed to investigate the prognostic value of the immune cells population in peripheral blood from patients with advanced gastric cancer treated with neoadjuvant chemotherapy. A total of 105 patients with advanced gastric cancer were evaluated in this study. Blood samples were collected before and 1 week after the last dose of chemotherapy. The percentage of CD3+, CD3+CD4+, CD3+CD8+, and CD4+CD25+Foxp3+ T cells was assessed using flow cytometry analysis. The relationship between T cell subsets and clinical outcome was evaluated. The percentage of CD3+CD8+ lymphocytes was significantly increased after chemotherapy and CD4+CD25+Foxp3+ regulatory T cells (Tregs) decreased ( p = 0.003 and p < 0.001, respectively). The percentage of CD3+CD8+ lymphocytes and Tregs was strongly associated with response to chemotherapy ( p = 0.017 and p < 0.030, respectively). Patients with high CD3+CD8+ T cells and low CD4+CD25+Foxp3+ Tregs had significantly increased overall survival ( p = 0.012 and p = 0.048, respectively). Neither CD3+ nor CD3+CD4+ T cells showed significant changes after chemotherapy or correlations with the clinical outcome. The positive correlation between a high CD3+CD8+ T cells or low CD4+CD25+Foxp3+ Tregs and clinical outcome indicates its key role in the prognosis of gastric cancer patients and may serve as a biomarker to identify patients likely to benefit from neoadjuvant chemotherapy.

Cytokine-induced killer (CIK) cells in cancer immunotherapy: report of the international registry on CIK cells (IRCC)

PURPOSE

Cytokine-induced killer (CIK) cells represent an exceptional T cell population uniting a T cell and natural killer cell like phenotype in their terminally differentiated CD3(+)CD56(+) subset, which features non-MHC-restricted tumor-killing activity. CIK cells are expandable from peripheral blood mononuclear cells and mature following the addition of certain cytokines. CIK cells have provided encouraging results in initial clinical studies and revealed synergistic antitumor effects when combined with standard therapeutic procedures.

METHODS

Therefore, we established the international registry on CIK cells in order to collect and evaluate data about clinical trials using CIK cells for the treatment of cancer patients. Moreover, our registry is expected to set new standards on the reporting of results from clinical trials using CIK cells. Clinical responses, overall survival (OS), adverse reactions and immunologic effects were analyzed in 45 studies present in our database. These studies investigated 22 different tumor entities altogether enrolling 2,729 patients.

RESULTS

A mean response rate of 39 % and significantly increased OS, accompanied by an improved quality of life, were reported. Interestingly, side effects of CIK cell treatment were minor. Mild fevers, chills, headache and fatigue were, however, seen regularly after CIK cell infusion. Moreover, CIK cells revealed numerous immunologic effects such as changes in T cell subsets, tumor markers, cytokine secretion and HBV viral load.

CONCLUSION

Due to their easy availability and potent antitumor activity, CIK cells emerged as a promising immunotherapy approach in oncology and may gain major importance on the prognosis of cancer.

Adoptive immunotherapy strategies with cytokine-induced killer (CIK) cells in the treatment of hematological malignancies

Cytokine-induced killer (CIK) cells are a heterogeneous population of immune effector cells that feature a mixed T- and Natural killer (NK) cell-like phenotype in their terminally-differentiated CD3+CD56+ subset. The easy availability, high proliferation rate and widely major histocompatibility complex (MHC)-unrestricted antitumor activity of CIK cells contribute to their particularly advantageous profile, making them an attractive approach for adoptive immunotherapy. CIK cells have shown considerable cytotoxicity against both solid tumors and hematological malignancies in vitro and in animal studies. Recently, initial clinical experiences demonstrated the feasibility and efficacy of CIK cell immunotherapy in cancer patients, even at advanced disease stages. Likewise, the clinical application of CIK cells in combination with standard therapeutic procedures revealed synergistic antitumor effects. In this report, we will focus our consideration on CIK cells in the treatment of hematological malignancies. We will give insight into the latest advances and future perspectives and outline the most prominent results obtained in 17 clinical studies. Overall, CIK cells demonstrated a crucial impact on the treatment of patients with hematological malignancies, as evidenced by complete remissions, prolonged survival durations and improved quality of life. However, up to now, the optimal application schedule eventually favoring their integration into clinical practice has still to be developed.

Efficacy of adjuvant immunotherapy with cytokine-induced killer cells in patients with locally advanced gastric cancer

Purpose

To determine the long-term efficacy of adjuvant immunotherapy with autologous cytokine-induced killer (CIK) cells for locally advanced gastric cancer patients.

Experimental design

One hundred and fifty-one patients with stage III/IV gastric cancer who had undergone gastrectomy were enrolled, assigned to two groups (immunotherapy group versus no immunotherapy group/or control group), and followed.

Results

The 5-year overall survival (OS) and 5-year disease-free survival (DFS) rates for immunotherapy versus control group were 32.4 versus 23.4 % (P = 0.071) and 28.3 versus 10.4 % (P = 0.044), respectively. For patients with intestinal-type tumors, the 5-year OS and DFS rates were significantly higher for immunotherapy (OS, 46.8 vs. 31.4 % and P = 0.045; DFS, 42.4 vs. 15.7 % and P = 0.023). In the immunotherapy group, the mean CD3⁺ level, CD4⁺ level, and CD4⁺/CD8⁺ ratio increased from 50.8, 26.5, and 0.9 %, respectively, at baseline to 62.6, 35.0, and 1.4 %, respectively, 1 week after the first CIK-cell treatment, returned to baseline after 2 months, and maintained a higher level (60.7 ± 8.2 %, 34.2 ± 7.1 %, and 1.3 ± 0.3 %, respectively) 2 months after 3 cycles of immunotherapy.

Conclusions

Adjuvant immunotherapy with CIK cells prolongs DFS in patients with locally advanced gastric cancer and significantly improves OS in patients with intestinal-type tumors. Intestinal-type tumors could be selected as an important indication for CIK-cell therapy. This treatment may help improve T-lymphocyte subset distribution and improve the host’s immune functions, but multiple cycles are necessary for long-term therapeutic efficacy.

Effects of red ginseng upon postoperative immunity and survival in patients with stage III gastric cancer

In this paper, we present evidence that the red ginseng powder from Panax ginseng C.A. Meyer inhibits the recurrence of AJCC stage III gastric cancer and shows immunomodulatory activities during postoperative chemotherapy, after a curative resection with D2 lymph node dissection. Flow cytometric analyses for peripheral T-lymphocyte subsets showed that the red ginseng powder restored CD4 levels to the initial preoperative values during postoperative chemotherapy. Depression of CD3 during postoperative chemotherapy was also inhibited by the red ginseng powder ingestion. This study demonstrated a five-year disease free survival and overall survival rate that was significantly higher in patients taking the red ginseng powder during postoperative chemotherapy versus control (68.2% versus 33.3%, 76.4% versus 38.5%, respectively, p < 0.05). In spite of the limitation of a small number of patients (n = 42), these findings suggest that red ginseng powder may help to improve postoperative survival in these patients. Additionally, red ginseng powder may have some immunomodulatory properties associated with CD3 and CD4 activity in patients with advanced gastric cancer during postoperative chemotherapy.

T-lymphocyte subsets in patients with AJCC stage III gastric cancer during postoperative adjuvant chemotherapy. American Joint Committee on Cancer

BACKGROUND AND AIMS

Advanced neoplastic diseases alter the immune response in cancer patients. The aim of this study was to evaluate the changes of T-lymphocyte subsets during postoperative adjuvant chemotherapy, and the relationship between T-lymphocyte subsets and tumor recurrence in AJCC stage III gastric cancers.

MATERIAL AND METHODS

Analysis of T-lymphocyte subsets was performed in 39 patients with stage III gastric adenocarcinoma who had undergone a curative gastric resection and postoperative chemotherapy. CirculatingT-lymphocyte subsets were measured on venous blood by using flow cytometry and monoclonal antibodies on preoperative day 1, and postoperative months 1, 3, and 6.

RESULTS

The 5-year disease-free survival rates of patients with stage 3a and 3b gastric cancer were 57.1% and 33.3%, respectively (p = 0.06). Values of CD3+ and CD4+ T-cells, and CD4+/CD8+ ratios were consistently lower in the recurrence group throughout the observation period. CD4+ T-cell counts were significantly lower in the recurrence group on preoperative day 1, and postoperative months 1 and 6. However, most values of the T-lymphocyte subsets showed no statistically significant difference when comparing the stage 3a and 3b disease patient groups.

CONCLUSIONS

The results of this study suggest that immunosuppression associated with CD3+ and CD4+ T-cell depression is a risk factor for postoperative recurrence in patients with stage III gastric cancer.

The role of cytotoxic T-lymphocytes in the prevention and immune surveillance of tumors--lessons from normal and immunodeficient mice

The idea of immunological surveillance against cancer has existed for nearly 100 years but as no conclusive evidence has yet been published the importance of the cellular immune defense in the detection and removal of incipient or existing tumors is still a hotly debated subject. However, in order to select a relevant immunotherapeutic strategy in the treatment of cancer, a fundamental understanding of the basic immunologic conditions under which a tumor develops and exists is a prerequisite. Therefore, a murine model was set up that we hoped would enable us to confirm or reject the theory of immunological surveillance. A large panel of methylcholanthrene induced tumors was established in T-cell immunodeficient nude mice and congenic normal mice to study the influence of the immune system on developing tumors. As nude mice developed tumors fastest and with the highest incidence, we concluded that in this model the immune system constituted a 'tumor-suppressive factor' delaying and sometimes abrogating tumor growth, i.e. performing immune surveillance. Immunogenicity of the tumors was assessed by transplantation back to normal histocompatible mice. Tumors originating from the immunodeficient nude mice turned out to be far more immunogenic than tumors from normal mice, resulting in a high rejection rate. CD8+ cytotoxic T cells were found to be indispensable for this rejection, leading to the conclusion that the cytotoxic T cells perform immune selection in normal mice, eliminating immunogenic tumor cell variants in the incipient tumor. In this review, we discuss the difficulties facing immunotherapy when conclusions are drawn from the presented observations and hypotheses.

Thymostimulin increases natural cytotoxic activity in patients with breast cancer

The effect of thymostimulin on the Natural Killer (NK) cytotoxic activity of peripheral blood mononuclear cells (PBMC) was investigated in 15 patients with breast cancer after finishing or during chemotherapy (CAF) and in 10 healthy controls. PBMC from these subjects were incubated in the presence of thymostimulin for varying periods of time (18 h or 5 days), and then used as effector cells against 51Cr-radiolabeled NK-sensitive (K-562) and NK-resistant (JY) target cells in cytotoxicity assays. No significant differences were observed between the NK-activity from breast cancer patients and healthy controls. Thymostimulin induced a dose- and time-dependent cytotoxic enhancing effect on the cytotoxic activity of PBMC from these patients against NK-sensitive K562 target cells. The thymostimulin (1000 ng/ml) significantly enhanced cytotoxic activity in PBMC from breast cancer patients who had previously received chemotherapy (p = 0.0277) against NK-sensitive cells. This increase was not statistically significant neither in PBMC from patients receiving chemotherapy nor in healthy controls (p > 0.05 in both cases). The incubation of PBMC from patients with breast cancer was not associated to a significant enhancement of the cytotoxic activity against NK-resistant target cells (p > 0.05). We also found that thymostimulin could synergize with interleukin-2 in inducing NK cytotoxic activity in PBMC after 18 h of culture (p = 0.0277). In conclusion, we have demonstrated that thymostimulin enhances the natural killer cytotoxic activity of PBMC from patients with breast cancer who have previously received chemotherapy.

Immunologic dysfunction in cancer

The interactions between the tumor and its host are complex, and many aspects of the immune system appear to be adversely affected directly or indirectly by the presence of the tumor. Virtually all of the processes involved in immune induction and action have been implicated in the observed deficient response in tumor-bearing patients. Improved understanding and molecular analysis of the mechanisms underlying the escape of tumors from immune surveillance may lead to the development of novel strategies for the prevention of T-cell immunosuppression in cancer patients, the development of novel immunotherapeutic strategies, and potentially prevention of tumor progression or development.

Circulating immune markers in advanced renal cell carcinoma during immunotherapy with interferon gamma

Circulating immune markers sICAM-1, sELAM-1, sMHC-I, beta 2-MG, sCD4 and sCD8 were evaluated prior to and during immunotherapy with biologically active doses of interferon gamma (IFN-gamma) in 16 patients with advanced renal cell carcinoma (RCC) over a period of 12 months. Compared to 20 healthy controls, significantly (P < 0.01) elevated baseline levels of circulating adhesion molecules sICAM-1 (mean 1166 vs 230 ng/ml) and sELAM-1 (70 vs 17 ng/ml) were found in all patients. Compared to responders (n = 2) or patients with stable disease (n = 2), progressive disease during therapy (n = 12) was associated with significantly (P < 0.05) higher mean concentrations of sICAM-1 (1574 vs 962 ng/ml) and sELAM-1 (86 vs 46 ng/ml). Pretherapeutic and intratherapeutic levels of sMHC-I among the RCC patients were significantly (P < 0.05) lower than among the controls (0.41 vs 0.8 ng/ml). sCD4 levels clearly showed the same tendency (24 vs 33 U/l). sCD8 baseline levels, by contrast, were significantly (P < 0.05) elevated (564 vs 336 U/l), reflecting either activation of the NK-cell subset or increased synthesis of CD8+ T-suppressor cells. Again, significantly (P < 0.05) higher intratherapeutic sCD8 concentrations were observable with progressive disease than with response to therapy or stable disease (721 vs 355 U/l). Interestingly, although the biologically active dose of IFN-gamma was defined by an increase in beta 2-MG release of at least 30% within 48 h after injection, none of the other markers showed any significant alteration following IFN-gamma administration, suggesting that IFN-gamma in vivo does not produce changes in circulating markers of activation that might be expected on the basis of its effects in vitro. The finding of significantly elevated concentrations of sICAM-1, sELAM-1 and sCD8 in the presence of low sCD4 and sMHC-I levels might be of clinical significance for indicating ongoing tumor progression.

Comparison of immunomodulative effects of the histamine-2 receptor antagonists cimetidine, ranitidine, and famotidine on peripheral blood mononuclear cells in gastric cancer patients

BACKGROUND

Histamine-2 receptor antagonist (H2-RA) have been shown to improve the function of various parts of the immune system. The proposed mechanism of the immunomodulative effects of H2-RA has been considered to be the inhibition of suppressor T-lymphocyte activity, an increase in interleukin-2 production, and an enhancement of natural killer cell activity. Most of these studies were done with cimetidine. Comparative data with other H2-RA are limited and conflict on immunomodulative effects. Comparison of the actions of H2-RA on the immune system is required.

METHODS

We compared the immunodulative effect of the H2-RAs cimetidine, ranitidine, and famotidine on peripheral blood mononuclear cells (PBMC) in normal controls and patients with gastric cancer. DNA synthesis, cytotoxicity against K562 cells, and the levels of soluble interleukin-2 receptor (sIL-2R) in supernatant were measured after addition of the various H2-RA to PBMC cultures.

RESULTS

Subjects with gastric cancer showed significantly higher levels of suppressor lymphocyte activity than normal controls. These levels were restored to levels of normal controls by the addition of cimetidine. Statistically significant lymphoblastogenesis and cytotoxicity against K562 cells were observed only in cimetidine-treated PBMC (p < 0.05); such effects were not observed in ranitidine- or famotidine-treated PBMC. Significantly increased levels of sIL-2R were found in supernatants obtained from culture flasks treated with cimetidine and phytohemagglutinin or ranitidine and phytohemagglutinin (p < 0.01).

CONCLUSIONS

Of the three H2-RAs tested, cimetidine had the strongest and famotidine the weakest immunomodulating effect. Only cimetidine augmented the cytotoxicity and proliferative response of lymphocyte to mitogen; neither ranitidine nor famotidine had such an effect. These results might be due to their structural differences. In addition, the immunologic effects of H2-RA are unlikely to be mediated via specific interaction at the H2 receptor.

Comparison of immunomodulative effects of histamine-2 receptor antagonists in gastric cancer patients: focus on the lymphoblastogenesis and cytotoxicity of peripheral blood mononuclear cells

A proposed mechanism of the immunomodulative effects of histamine-2 receptor antagonist (H2-RA) has been considered to be the inhibition of suppressor T-lymphocyte activity, an increase in interleukin-2 production of helper T-lymphocytes, and an enhancement of natural killer cell activity. Since there is a lack of comparative data about the immunomodulative effects of various H2-RAs, cimetidine, ranitidine and famotidine on peripheral blood mononuclear cells (PBMC), study of the comparison of the actions of H2-RA will be required. We compared the immunomodulative effect of each H2-RA on PBMC in patients with gastric cancer. DNA synthesis, cytotoxicity of PBMC against K562 cells and gastric cancer cell lines, and the levels of supernatant soluble interleukin-2 receptor (sIL-2R) were measured after the addition of each H2-RA, respectively. Increased suppressor cell activities were attenuated and restored to the levels of normal controls by the addition of cimetidine to H2-RA. Statistically significant lymphoblastogenesis and cytotoxicity against K562 cells were observed only in cimetidine-treated PBMC (P < 0.05). Such effects were not observed in ranitidine- or famotidine-treated PBMC. Neither cimetidine- nor ranitidine-activated activated PBMC showed any significant cytotoxicity against gastric cancer cells. Significantly increased levels of sIL-2R were found in supernatants obtained from culture flasks treated with cimetidine or ranitidine and phytohemagglutinin (P < 0.01). A significant correlation was found between the cytotoxicity of cimetidine- or ranitidine-treated PBMC and supernatant sIL-2R (P < 0.05). In conclusion, the most strongly modulative substance among H2-RAs was cimetidine and the least modulative drug was famotidine.(ABSTRACT TRUNCATED AT 250 WORDS)

Flow cytometric study of lymphocyte subsets in patients at different stages of colorectal carcinoma

PURPOSE

The evaluation of lymphocyte subsets by using monoclonal antibodies in neoplastic patients has provided different results, partly in relation to the stage of the disease. Therefore, as a preliminary study of cancer patients treated with immunomodulating drugs, an analysis of lymphocyte subsets was performed in colorectal carcinoma patients.

METHODS

In this study, a flow cytometric evaluation of lymphocyte subsets was performed in 33 patients affected by colorectal carcinoma, with or without metastases.

RESULTS

A significant reduction of hemoglobin concentrations and hematocrit was observed in all of these subjects, associated with an evident increase of white blood cells, platelets, and HLA DR-positive T lymphocytes, whereas CD 3-CD 4-positive and CD 20-positive lymphocyte concentrations were decreased. Subjects without metastases showed an evident decrease of hemoglobin concentrations and an increase of white blood cells, platelets and CD 3-HLA DR-positive lymphocytes, while patients with disseminated disease also had reduced mean values of hematocrit, red blood cells, CD 3-CD 4-positive, and CD 20-positive lymphocytes.

CONCLUSIONS

The main differences between colorectal carcinoma patients with or without metastases were represented by a decrease of red blood cells, CD 3-CD 4-positive, and CD 20-positive lymphocyte concentrations in the latter group.

A small GTP-binding protein is frequently overexpressed in peripheral blood mononuclear cells from patients with solid tumours

ras oncoproteins and ras-related proteins constitute a large family of the small GTP-binding protein family. The rab branch of the ras superfamily is involved in the intracellular transport along the secretory and endocytic pathway in eukaryotic cells. We here demonstrate that a member of the rab branch, the rab2 protein, is frequently overexpressed in peripheral blood mononuclear cells from patients with solid neoplasms. Moreover, this expression is shown to be greatly modified during the course of therapy. Our results provide strong evidence for the implication of a small GTP-binding protein in immunological events associated with neoplastic diseases. The precise cellular population involved as well as the potential prognostic value of this process remains to be determined.

Utilization of the MHC class I (H-2Kb) purified molecule and its synthetic peptides for inhibition of Kb-specific suppressor T cells and their induction in vivo by the MHC peptides

Six synthetic peptides of the MHC class I molecule corresponding to individual H-2Kb participants in amino acid sequences of domains alpha 1 (peptide 1 and 2) and alpha 2 (peptides 3, 4, 5, 6) were selected. Kb-specific suppressor T cells (Ts) were induced in vivo in mice, then pretreated with a set of peptides and assayed by proliferation decrease in a three-cell lymphocyte culture (MLC). The effector function of Ts was abolished by the complex of the alpha 2-domain peptides (but not by the alpha 1-domain peptides) and decreased by particular peptides separately (4, 5, 6) of the alpha 2-domain. Both alpha 1- and alpha 2-domain peptides, added in high concentration, decreased otherwise efficient enrichment of Ts during the absorption-elution procedure on the syngeneic macrophage (M psi) monolayers. A similar significant effect was observed using the purified Kb molecule (100 micrograms/ml) in the allogeneic M psi monolayer. Interaction between Ts receptors and some MHC peptides indicates in effector Ts activation in vivo by induction with peptides 5 and 6 of the alpha 2-domain. The fine mechanisms of interaction between MHC class I molecule epitopes and T-cell receptors of each of the T-cell subsets separately are presently being studied.

In vitro modulatory effects of interleukin-3 on macrophage activation induced by interleukin-2

BACKGROUND

The concomitant activation of macrophage-mediated immunosuppressive events might represent one of the most important biologic factors responsible for the decreased efficacy of cancer immunotherapies, including that of interleukin (IL)-2. In previous studies, the authors observed that the increase in the soluble IL-2 receptor (SIL-2R) and neopterin levels was related to the generation of macrophage-mediated immunosuppression and associated with a reduced clinical efficacy during IL-2 cancer immunotherapy. Because both cytokines and neurohormones may influence the macrophage system, the current study was done to evaluate the effects of IL-3 and of the pineal hormone melatonin (MLT) on monocyte response to IL-2 administration.

METHODS

Peripheral blood monocytes were incubated with different concentrations of IL-2, IL-3, and MLT, either alone or in association.

RESULTS

SIL-2R, neopterin, and tumor necrosis factor-alpha mean concentrations in the medium significantly increased during incubation with IL-2 at a concentration of 100 Cetus units/ml. IL-3 alone, at a dose of 10 ng/ml, also stimulated tumor necrosis factor release; no effect was found on SIL-2R and neopterin. The IL-2-induced neopterin rise was blocked by a concomitant incubation with IL-3 at a dose of 10 ng/ml. Finally, the concomitant incubation with IL-3 and MLT further inhibited neopterin release and significantly decreased IL-2-induced SIL-2R secretion.

CONCLUSIONS

These results suggest that IL-3 alone or in association with MLT may modulate macrophage functions during cancer immunotherapy with IL-2 and decrease the IL-2-induced macrophage activation.

Modulation of macrophage response to interleukin-2 immunotherapy by interleukin-3 in cancer patients

It has been observed that neopterin, a specific marker of macrophage activation, increases during cancer immunotherapy with IL-2, and this effect is mediated by interferons produced by IL-2-stimulated lymphocytes. Moreover, our previous studies have shown that neopterin rise during IL-2 immunotherapy is associated with an enhanced release of soluble IL-2 receptor (SIL-2R), which may suppress IL-2-dependent immune functions. This finding would suggest that neopterin increase may be related to the generation of suppressive events, which occur during IL-2 immunotherapy. On the basis of the documented modulatory effect of IL-3 on macrophage functions, we have evaluated the influence of IL-3 on neopterin secretion during IL-2 immunotherapy. The study was performed in advanced lung cancer patients. We have investigated 9 immunotherapeutic courses consisting of IL-2 (6M IU/day s.c. for 5 days/week for 3 weeks) plus IL-3 (1 microgram/(kg x day) i.v. for 14 days, starting 7 days before IL-2). The results were compared to those found during 18 courses with IL-2 alone. Mean neopterin levels increased significantly during IL-2 alone, but not in response to IL-3 plus IL-2. SIL-2R rise was significantly higher during IL-2 than during IL-3 plus IL-2. Mean numbers of NK cells and activated lymphocytes increased significantly in both groups of patients, but were significantly lower at the end of the treatment in patients receiving IL-2 alone than in those treated with IL-3 plus IL-2.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of serum levels of tumour necrosis factor-alpha (TNF-alpha) and soluble IL-2 receptor (sIL-2R) and CD4, CD8 and natural killer (NK) populations during infrared pulsed laser device (IPLD) treatment

The purpose of this study was to evaluate serum levels of TNF-alpha, sIL-2R and distribution of peripheral leucocyte subsets in patients with advanced neoplastic disease undergoing IPLD treatment. Fifteen cancer patients with evidence of persistent disease were further divided in two groups according to outcome at the end of the period of clinical evaluation: group 1 patients were still alive and group 2 patients had died. Our results show: (i) an increase in the initial level of TNF-alpha in both groups; (ii) a decrease in TNF-alpha levels during the follow up of group 1 patients; (iii) a significant increase in serum levels of sIL-2R in patients in group 2 compared with those in group 1; (iv) a progressive and constant increase in TNF-alpha levels in group 2; (v) a decrease in CD4+CD45RA+ subpopulation in both groups; (vi) an increase in CD25+ cells; (vii) an increase in CD4+, CD4+CD45RA+ and CD25+ cells during the follow up of group 2 patients. The data generated here form the basis for further investigations on the use of IPLD as a single agent and in combination with other biological response modifiers in cancer patients.

Postoperative increase in soluble interleukin-2 receptor serum levels as predictor for early recurrence in non-small cell lung carcinoma

It is known that interleukin-2 (IL-2) plays an important role in the activation of host antitumor immune response. In addition to IL-2 cell surface receptor, a soluble form of IL-2 receptor (SIL-2R) may be released in the blood and potentially be involved in the regulation of IL-2 availability. High SIL-2R levels have been found in patients with lung cancer. The current study evaluated the influence of changes in SIL-2R serum levels during the perioperative period on early relapse rate in patients with operable non-small cell lung cancer. The study included 60 patients (epidermoid carcinoma, 33; adenocarcinoma, 27). Serum levels of SIL-2R were measured with an enzyme immunoassay before surgery and 7 and 30 days after surgery. A surgery-induced increase in SIL-2R levels was seen 7 days after surgery in 38 of 60 patients. On the 30th day after surgery, SIL-2R values were lower than the preoperative values in 32 patients (Group A) or still greater in the other 28 patients (Group B). After a median follow-up of 10 months, relapse occurred in 19 of 60 patients. The relapse rate was significantly higher in Group B than in Group A patients (16 of 28 versus 3 of 32, respectively; P less than 0.001). This difference also was significant in relation to histotype and node status. This study shows that the persistence of increased SIL-2R levels in the postoperative period is associated with a higher early relapse rate in patients with operable non-small cell lung cancer. The impact of SIL-2R levels on relapse suggests that host immune defenses may influence the clinical course of patients with lung cancer. Therefore, the evaluation of SIL-2R in the perioperative period may represent a new prognostic biologic factor in operable non-small cell lung cancer.

Pneumocystis carinii pneumonia associated with profound lymphopenia and abnormal T-lymphocyte subset ratios during treatment for early-stage breast carcinoma

Two women with Stage II breast carcinoma treated with lumpectomy followed by breast irradiation and adjuvant chemotherapy developed Pneumocystis carinii pneumonia while receiving cytotoxic chemotherapy. Neither woman had evidence of immunosuppression before therapy. They both had profound lymphopenia, reversed CD4/CD8 ratios, and normal peripheral blood total leukocyte counts at the time of their infections. Both women were seronegative for human immunodeficiency virus type 1 and had no risk factors for such an infection. The patients' CD4 lymphocyte counts increased after chemotherapy for breast carcinoma was discontinued. Thus, it appears that the therapy they received may have caused severe T-lymphocyte mediated immunosuppression.

Number of helper T cells and phytohemagglutinin stimulation correlate in cancer patients

Mononuclear cells from 12 normal controls (co), 10 advanced untreated (c1), and 6 advanced treated cancer patients (c2) have been isolated. The numbers of mononuclear cells bearing Leu1, Leu2, Leu3, Leu2/HLA-DR and LeuM3 were measured with a fluorescence-activated cell sorter. Only the quantity of helper T cells (Leu3) was decreased in cancer patients (co: 0.89, cl: 0.32, c2: 0.44 x 10(9)/l). Expression of all other markers, including activated suppressor T cells (Leu2/HLA-DR), did not differ significantly from the control. The proliferation of the lymphocytes was determined in a phytohemagglutinin-culture assay. The cancer groups showed a significantly decreased response (co: 95.8 x 10(9), cl: 28.7 x 10(9), c2: 25.7 x 10(9) cpm). These values correlated with the number of helper T cells but not with the suppressor T cells. Monocytes of cancer patients absorbed significantly more immunoglobulins than the monocytes of controls. The addition of indomethacin or isoprinosine to phytohemagglutinin-culture assay increased the proliferation of lymphocytes from both the cancer patients and normal controls.

Soluble interleukin-2 receptor and soluble CD8 antigen levels in serum from patients with non-resectable lung cancer

In a preliminary longitudinal study two women with histologically verified adenocarcinoma of the lung, without simultaneous infectious or inflammatory conditions, were seen every 2 weeks until death. In one of the patients serum soluble interleukin-2 receptor (sIL-2R) levels rose progressively while the levels for the other patient increased during the second half of the observation period. Serum soluble CD8 antigen (sCD8 Ag) showed a pattern dissimilar to the one for sIL-2R. In a retrospective cross-sectional study circulating levels of sIL-2R and sCD8 Ag were measured before explorative thoracotomy in a total of 65 patients with histologically proven non-resectable carcinoma of the lung. The sIL-2R levels were significantly increased independently of histological subclassification while sCD8 Ag was increased only in patients with small-cell lung cancer. There was no correlation between pre-operative values and length of survival.

Lymphocyte activation in patients with acute myeloid leukaemia. Evidence for the presence of myeloblast antigen?

A group of 27 patients with acute myeloid leukaemia (AML), 15 with active disease and 12 in complete remission, were investigated for evidence of T cell activation. The parameters of T cell activation measured were the serum levels of soluble interleukin-2 receptor (sIL-2R), soluble CD4 (sCD4) and soluble CD8 (sCD8) molecules and the proportions of T cells expressing the cytotoxicity-linked cytoplasmic serine esterase. All patients studied with active disease had elevated sIL-2R and sCD8 molecules and an elevated proportion of T cells expressing serine esterase. Patients studied in complete remission also had elevated sIL-2R. sCD8 and serine-esterase-positive T cells, but values were lower than those studied in active disease. These patients were all studied in the absence of any ongoing or recent infection or exposure to homologous blood products, either of which could potentially affect these parameters. In the absence of any obvious alternative cause, we suggest these data indicate that AML leukaemia blast cells may be immunogenic and lead to the activation of cytotoxic T cells.

Effects of radiolabelled monoclonal antibody infusion on blood leukocytes in cancer patients

This study was undertaken to investigate the effects of a single infusion of radiolabelled murine monoclonal antibody (MAb) on peripheral blood leukocytes in cancer patients. Eleven patients with disseminated colon cancer, malignant melanoma, or lung adenocarcinoma were infused with 111In-labelled anti-ZCE 025, anti-p97 type 96.5c, or LA 20207 MAb, respectively. Blood samples were obtained before infusion, immediately after infusion (1 hr), and at 4 and 7 days postinfusion. Flow cytometry analysis of CD3+, CD4+, CD8+, CD16+, and CD19+ lymphocytes showed increasing CD4:CD8 ratios in seven patients after infusion. This phenomenon was not restricted to antibody subclass or to type of cancer. Two of the remaining patients exhibited a marked post-infusion increase in CD8+ cells. In all three patients with malignant melanoma, decreasing levels of CD16+ lymphocytes were noted after infusion and natural killer cell cytotoxicity showed fluctuations which paralleled the changes in the CD16+ subpopulation. Oxygen radical production by phagocytic cells was markedly affected in three subjects. These results suggest that a single infusion of radiolabelled murine MAb may alter the balance of critical lymphocyte subpopulations and modulate other leukocyte responses in cancer patients.

Development of splenic natural suppressor (NS) cells in Ehrlich tumor-bearing mice

Spleen cells from C57BL/6J mice bearing Ehrlich carcinoma growing as a solid tumor show progressive unresponsiveness to concanavalin A (Con A) and lipopolysaccharide (LPS) mitogens. This is accompanied by striking spleen enlargement with marked hematopoietic activity. Lymphoproliferative assays of normal spleen cells in co-culture with tumor-bearing spleen cells (TBSC) show that: (a) TBSC contain non-specific suppressor cells able to abrogate both Con A and LPS responses, or mixed lymphocyte reaction, of normal spleen cells and (b) suppression by TBSC is MHC-unrestricted, non-prostaglandin-mediated and greatly enhanced by Con A supernatants. Suppressor cells associated with TBSC are large, low-density cells without markers of mature B or T lymphocytes or of the mononuclear phagocyte system. Most appear to be asialo-GM1-negative, as suppression was only partially inhibited by treatment with anti-asialo-GM1 and complement. Since NK activity is lacking in TBSC, our data strongly suggest that these "null" suppressor cells are related to the natural suppressor (NS) cells found described in normal bone-marrow and neonatal spleens, or induced in adult spleens by total lymphoid irradiation, graft-vs.-host disease, or cyclophosphamide treatment.

T-cell markers in tumor-infiltrating lymphocytes of head and neck cancer

Fresh suspensions of tumor-infiltrating lymphocytes (TIL) from 16 patients with squamous cell carcinoma of the head and neck (SCCHN) were examined for T-cell markers including CD4 (helper-inducer), CD8 (cytotoxic-suppressor), natural killer (NK) cell, and activation surface markers using monoclonal antibodies and two-color flow cytometry. Two of 8 (25%) patients with a CD4/CD8 ratio of less than 1 developed cervical lymph node metastases; none had extracapsular spread. Six of 8 (75%) patients with a CD4/CD8 ratio of greater than 1 developed cervical metastases; 5 of 6 (83%) exhibited extracapsular spread. An increased CD4/CD8 ratio was attributable to a decrease in CD8+ cells. A CD4/CD8 ratio of greater than 1 may be a useful prognostic indicator of the development of cervical metastases.