Dose-finding study of anti-CD25 antibody for targeting regulatory T cells in locoregional immunotherapy of malignant effusion

Effects of low-dose anti-CD25 antibody on targeting regulatory T (Treg) cells in vitro and in vivo were investigated. Human-mouse chimeric anti-CD25 monoclonal antibody basiliximab was administered into the effusion cavity, followed by locoregional immunotherapy using OK-432 on day 7. Peripheral blood mononuclear cells and effusion lymphocytes (ELs) were collected before and after the basiliximab administration and subjected to further investigations. Surface phenotypes, IFN-gamma production, cytotoxic activity and foxp3 expression of ELs were assessed by flow cytometry, ELISA, 51Cr-releasing assay, and RT-PCR analysis, respectively. We observed that a low concentration of 0.01 microg/ml basiliximab effectively targeted CD4+CD25(bri) Treg cells while preserving CD4+CD25(dim) activated T cells in vitro. This concentration of basiliximab significantly augmented interferon (IFN)-gamma production of ELs when interleukin (IL)-2 was added on day 0 or on day 1 after basiliximab. In the clinical study, intracavitary administration of basiliximab on day 0 followed by OK-432 on day 7 was as safe, well-tolerated, and effective as using OK-432 alone, and a low-dose of 0.002-0.005 mg/kg basiliximab could target CD4+CD25(bri) cells for at least 3 days while relatively preserving CD4+CD25(dim) cells. Foxp3 expression of ELs was not changed definitely by the intracavitary basiliximab. These results suggest that low-dose basiliximab can target Treg cells in vitro and in vivo, and subsequently augment the activation of ELs. Locoregional immunotherapy of malignant effusion using the Treg cell-conditioning regimen with low-dose basiliximab followed by OK-432 administration on day 0 or on day 1 should be evaluated for clinical efficacy in the next phase II trial.

Detection of B cell lymphoma involvement in T cell-rich serous fluid by immunoglobulin gene rearrangement: a report of 2 cases

BACKGROUND

Cytology, flow cytometry and gene rearrangement studies are methods to detect lymphoma involvement of body fluid. The cytology of the effusion is equivocal for lymphoma involvement.

CASES

We report 2 cases of diffuse large B cell lymphoma with massive lymphocyte predominant serous fluid, ascites in one case and pleural effusion in the other. Immunophenotypic analysis by flow cytometry showed that lymphoid cells express only T cell markers. Lymphoma involvement of effusion was confirmed by immunoglobulin gene rearrangement detected by polymerase chain reaction.

CONCLUSION

Our case demonstrated the value of gene rearrangement study in establishing diagnosis of equivocal cases.

Diagnostic considerations in prolymphocytes in pleural fluid: a case report

BACKGROUND

Prolymphocytes are nucleolated cells that are the defining features of the 2 chronic lymphoproliferative disorders, prolymphocytic leukemia (PLL) and chronic lymphocytic leukemia (CLL) with increased prolymphocytes. Prolymphocytes appear relatively unfamiliar in cytopathology practice, and, particularly when present in body fluids, may resemble blasts or adult T-cell leukemia/ lymphoma (ATLL) cells.

CASE

A 32-year-old man, referred to us with a diagnosis of acute leukemia, presented with shortness of breath for 2 months and loss of appetite for 3 months. He had enlarged liver and spleen, 6 and 8 cm, respectively, below the costal margin and pleural effusion. The raised total leukocyte count chiefly comprised prolymphocytes that, especially in the pleural fluid, had prominent nucleoli and significant pleomorphism, raising the possibility of blasts or ATLL.

CONCLUSION

Prolymphocytes in body fluids can be misinterpreted as blasts or even ATLL cells. Better awareness among cytopathologists about prolymphocytes and the disease states in which they occur, as well as insistence, in a clinical setting of leukemia, on interpreting the pleural fluid in relation to the clinical and laboratory findings, especially those of the peripheral blood and bone marrow, can prevent misdiagnosis. Equally importantly, immunophenotyping must be done in such situations.

[Impact of intrapleural hyperthermic perfusion on immunologic reaction state of cytokines TH1/TH2 of lung carcinoma patients with malignant pleural effusion]

BACKGROUND & OBJECTIVE

Intrapleural hyperthermic perfusion is the distinctive therapy of malignant pleural effusion (MPE) caused by lung carcinoma. The expression pattern of T helper type 1 (Th1)/Th2 is an important index that reflects antitumor immunologic function. This study was to evaluate the therapeutic effect of intrapleural hyperthermic perfusion on MPE, and to investigate the impact of intrapleural hyperthermic perfusion on the immunologic reaction state of lung carcinoma patients with MPE by observing the expression pattern of cytokines Th1/Th2.

METHODS

A total of 24 lung carcinoma patients with MPE underwent intrapleural hyperthermic perfusion with 43 celsius warmed normal saline for 60 min under video-assisted thoracoscopic surgery (VATS). The responses of pleural effusion, adverse events, life quality and survival time were observed. The concentrations of Th1/Th2-related cytokines interferon-gamma (IFN-gamma), interleukin-2 (IL-2)/IL-4, and IL-10 in peripheral blood and pleural effusion were detected by ELISA, and their mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

Neither operation-related death nor postoperative complication occurred. The total response rate of pleural effusion control was 100%, including 23 cases of complete remission (CR) and 1 case of partial remission (PR). No recurrence of MPE occurred. The quality of life of all patients had been improved. The median survival time was 18.3 months. The 1-and 2-year survival rates were 91.7% and 16.7%. The concentrations and positive rates of IL-2 and IFN-gamma were significantly lower and those of IL-4 and IL-10 were significantly higher in peripheral blood and pleural effusion before hyperthermia than in those after hyperthermia (P<0.05).

CONCLUSIONS

Intrapleural hyperthermic perfusion under VATS is a safe and effective treatment for MPE caused by lung carcinoma. It can convert the predominant state of Th2 cytokines in lung carcinoma patients with MPE to that of Th1 cytokines.

A phase I clinical trial of single-dose intrapleural IFN-beta gene transfer for malignant pleural mesothelioma and metastatic pleural effusions: high rate of antitumor immune responses

PURPOSE

This phase 1 dose escalation study evaluated the safety and feasibility of single-dose intrapleural IFN-beta gene transfer using an adenoviral vector (Ad.IFN-beta) in patients with malignant pleural mesothelioma (MPM) and metastatic pleural effusions (MPE).

EXPERIMENTAL DESIGN

Ad.IFN-beta was administered through an indwelling pleural catheter in doses ranging from 9 x 10(11) to 3 x 10(12) viral particles (vp) in two cohorts of patients with MPM (7 patients) and MPE (3 patients). Subjects were evaluated for (a) toxicity, (b) gene transfer, (c) humoral, cellular, and cytokine-mediated immune responses, and (d) tumor responses via 18-fluorodeoxyglucose-positron emission tomography scans and chest computed tomography scans.

RESULTS

Intrapleural Ad.IFN-beta was generally well tolerated with transient lymphopenia as the most common side effect. The maximally tolerated dose achieved was 9 x 10(11) vp secondary to idiosyncratic dose-limiting toxicities (hypoxia and liver function abnormalities) in two patients treated at 3 x 10(12) vp. The presence of the vector did not elicit a marked cellular infiltrate in the pleural space. Intrapleural levels of cytokines were highly variable at baseline and after response to gene transfer. Gene transfer was documented in 7 of the 10 patients by demonstration of IFN-beta message or protein. Antitumor immune responses were elicited in 7 of the 10 patients and included the detection of cytotoxic T cells (1 patient), activation of circulating natural killer cells (2 patients), and humoral responses to known (Simian virus 40 large T antigen and mesothelin) and unknown tumor antigens (7 patients). Four of 10 patients showed meaningful clinical responses defined as disease stability and/or regression on 18-fluorodeoxyglucose-positron emission tomography and computed tomography scans at day 60 after vector infusion.

CONCLUSIONS

Intrapleural instillation of Ad.IFN-beta is a potentially useful approach for the generation of antitumor immune responses in MPM and MPE patients and should be investigated further for overall clinical efficacy.

Differential cytokine levels and immunoreactivities against Mycobacterium tuberculosis antigens between tuberculous and malignant effusions

Much effort has been devoted to the identification of immunologically important factors in tuberculous pleurisy (TBP) and malignant pleurisy (MP) to improve the differential diagnosis of the two major causes of lymphocyte-dominant pleurisy. This study evaluated the immunoreactivity and potential diagnostic utility of both host (cytokines and chemokines) and pathogen (mycobacterial proteins) factors in pleural effusions. Effusion samples were collected from 41 patients with MP caused by lung cancer and from 81 patients with TBP. The concentrations of nine cytokines and chemokines (interleukin (IL)-12 p40, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, IL-6, IL-10, CXCL8/IL-8, CXCL10/IP-10, CCL3/MIP-1alpha, and CCL4/MIP-1beta) and antibody responses (IgG, IgM, and IgA) against five Mycobacterium tuberculosis antigens (early secreted antigenic target (ESAT)-6, 30-kDa, MTB12, 38-kDa, and a heparin-binding hemagglutinin (HBHA)) were determined in pleural fluids using enzyme-linked immunosorbent assays (ELISA). In the logistic regression, IFN-gamma (odds ratio, 7.178; 95% confidence interval (CI), 2.258-22.817; p=0.001), IL-12 p40 (odds ratio, 11.037; 95% CI, 3.38-36.037; p<0.001), and IL-6 (odds ratio, 3.295; 95% CI, 1.147-9.463; p=0.027) were found to be statistically significant cytokines predicting tuberculous from malignant effusions. Although IgG responses to all of the M. tuberculosis antigens tested were significantly higher in effusions from TBP (p<0.001) compared with those from MP, the logistic regression showed IgG levels for ESAT-6 and MTB12 to be statistically significant for differentiation of TBP from MP. HBHA showed the highest sensitivity of IgM antibody responses in TBP in comparison with other antigens. These data indicate that selected mycobacterial antigens (ESAT-6 and MTB12) and cytokine markers (IFN-gamma, IL-12p40, and IL-6) provide useful information for differentiating tuberculous and malignant effusions in clinical practice.

[The disappearance of CD20 positive lymphocytes in the pleural effusion after intrapleural application of rituximab]

A 63 year old woman with non-Hodgkin lymphoma presented with unilateral pleural effusion, which when aspirated revealed CD19 and CD20 positive malignant cells. Prior to this, the patient had received several lines of chemotherapy (CHOP, VAD, FED) with no effect on pleural effusion. Repeated percutaneous drainage procedures were unable to control the effusion either. Rituximab was therefore instilled in a dose escalating manner via repeated pleurocenteses. Fifty days after the application of rituximab, pleural effusion was still present but reduced in size. Flow cytometry and immunocytochemistry performed on the same day showed CD19 positive cells which were lacking CD20 epitope, which could be explained by either engagement or destruction of the CD20 epitope upon interaction with rituximab making the detection of the CD20 molecule impossible by routine flow cytometry. What is especially interesting is the fact that even 50 days after the application of rituximab intrapleurally no new CD20 positive cells could be found in the pleural effusion by immunochemistry or flow cytometry, opening an interesting issue concerning the length of rituximab's activity when applied locally. Although our patient had no adverse effects, further analysis of rituximab's activity and safety when applied intrapleurally is warranted.

Flow cytometric immunphenotyping of epithelial cancer cells in effusions—Technical considerations and pitfalls

BACKGROUND

Data regarding the role of flow cytometry (FCM) in the characterization of malignant effusions are limited to date. In the present study, we optimized the conditions for FCM immunphenotyping of effusions using a four-color analysis and investigated aspects related to the advantages and limitations of this method in this setting.

METHODS

FCM analysis optimization for the study of epithelial cells was undertaken using five carcinoma cell lines, and subsequently applied to malignant pleural and peritoneal effusions using antibodies against epithelial and mesothelial markers (Ber-EP4 and EMA), CD138, and integrin subunits. FCM of frozen versus fresh specimens and the performance of FCM compared to immunhistochemistry were evaluated.

RESULTS

FCM optimization was achieved and applied to clinical specimens, with resulting detection of epithelial markers and adhesion molecules on cancer cells. Frozen clinical specimens and cell lines showed reduced CD138 expression compared to fresh specimens, with conservation of the remaining epitopes. FCM generally showed comparable performance to immunhistochemistry.

CONCLUSIONS

FCM is an effective method for characterization of cancer cells in clinical effusion specimens in both the diagnostic and research setting, and is comparable to immunhistochemistry in terms of sensitivity and specificity, with the additional advantage of providing quantitative data. The majority of epitopes are conserved in frozen cells, but a minority may be lost, suggesting that the thorough testing of each antibody in both conditions is mandatory.

Potential role of natural killer cells in controlling growth and infiltration of AIDS-associated primary effusion lymphoma cells

Natural killer (NK) cells are an important component of the innate immune response against microbial infections and tumors. Direct involvement of NK cells in tumor growth and infiltration has not yet been demonstrated clearly. Primary effusion lymphoma (PEL) cells were able to produce tumors and ascites very efficiently with infiltration of cells in various organs of T-, B- and NK-cell knock-out NOD/SCID/gammac(null) (NOG) mice within 3 weeks. In contrast, PEL cells formed small tumors at inoculated sites in T- and B-cell knock-out NOD/SCID mice with NK-cells while completely failing to infiltrate into various organs. Immunosupression of NOD/SCID by treatment with an antimurine TM-beta1 antibody, which transiently abrogates NK cell activity in vivo, resulted in enhanced tumorigenicity and organ infiltration in comparison with non-treated NOD/SCID mice. Activated human NK cells inhibited tumor growth and infiltration in NOG mice. Our results suggest that NK cells play an important role in growth and infiltration of PEL cells, and activated NK cells could be a promising immunotherapeutic tool against tumor or virus-infected cells either alone or in combination with conventional therapy. The rapid and efficient engraftment of PEL cells in NOG mice also suggests that this new animal model could provide a unique opportunity to understand and investigate the mechanism of pathogenesis and malignant cell growth.

Elevated pleural fluid RCAS1 is a diagnostic marker and outcome predictor in lung cancer patients

RCAS1, a type II membrane protein also secreted in soluble form, may be important in tumor cell evasion of immune surveillance and contribute to the aggressiveness of human tumors. We examined the implications of elevated pleural fluid RCAS1 at the onset of effusion in lung cancer patients. Of 102 patients presenting with pleural effusion, 59 proved to have a malignant effusion and 43, nonmalignant. Malignant effusions exhibited higher RCAS1 concentrations than nonmalignant effusions (mean +/- SD; 36.3 +/- 114 vs. 2.7 +/- 1.8 U/ml; p=0.014). Lung cancer patients with pleural fluid RCAS1 concentrations below 15 U/ml had a longer mean survival than those with higher concentrations (4.7 vs. 1.7 months; p<0.05). By multivariate analysis, pleural fluid RCAS1 was an independent prognostic factor in lung cancer patients with effusion. In conclusion, RCAS1 determination at onset of pleural effusion is informative for both diagnosis and outcome prediction in lung cancer patients.

Mesothelioma environment comprises cytokines and T-regulatory cells that suppress immune responses

Malignant mesothelioma is a cancer with dismal prognosis. The objective of the present study was to address the role of the immune system, tumour micro-environment and potential immunosuppression in mesothelioma. Expression profiles of 80 cytokines were determined in the supernatant of mesothelioma cell lines and the original patient's pleural effusion. Influx of immune effector cells was detected by immunohistochemistry. Angiogenin, vascular endothelial growth factor, transforming growth factor-beta, epithelial neutrophil-activating protein-78 and several other proteins involved in immune suppression, angiogenesis and plasma extravasation could be detected in both supernatant and pleural effusion. Surrounding stroma and/or infiltrating cells were the most likely source of hepatocyte growth factor, macrophage inflammatory protein (MIP)-1delta, MIP-3alpha, neutrophil-activating peptide-2, and pulmonary and activation-regulated chemokine that can cause leukocyte infiltration and activation. There was a massive influx of CD4+ and CD8+ T-lymphocytes and macrophages, but not of dendritic cells, in human mesothelioma biopsies. It was further demonstrated that human mesothelioma tissue contained significant amounts of Foxp3+CD4+CD25+ regulatory T-cells. When these CD25+ regulatory T-cells were depleted in an in vivo mouse model, survival increased. Mesothelioma is infiltrated by immune effector cells but also contains cytokines and regulatory T-cells that suppress an efficient immune response. Immunotherapy of mesothelioma might be more effective when combined with drugs that eliminate or control regulatory T-cells.

Expression of HLA-G in malignant mesothelioma and clinically aggressive breast carcinoma

The aim of the present study was to evaluate HLA-G expression in breast carcinoma and malignant mesothelioma (MM). Malignant breast carcinoma effusions (46) and corresponding solid tumors (39) and 104 MM (26 effusions, 78 solid tumors) were analyzed using immunohistochemistry (IHC). HLA-G protein and mRNA expression were further studied using immunoblotting (IB) and RT-PCR. HLA-ABC expression was analyzed using flow cytometry (FCM). IHC showed predominantly focal HLA-G expression in 12 of 46 (26%) breast carcinoma effusions and 16 of 39 (41%) solid lesions. In MM, 20 of 78 (26%) solid lesions and 14 of 26 (54%) effusions were focally HLA-G positive. Expression in MM was higher in effusions (p=0.008). IB showed more frequent HLA-G expression in MM compared with breast carcinoma effusions, while RT-PCR showed HLA-G mRNA expression in both tumors. FCM showed conserved HLA-ABC expression in 15 of 15 effusions. Breast cancer patients with HLA-G-positive tumor cells had shorter disease-free survival (mean 37 vs 85, median 25 vs 31 months), though not significantly (p=0.14). In conclusion, HLA-G is focally expressed in MM and breast carcinoma, while HLA-ABC expression is conserved. However, the up-regulated expression of HLA-G in MM effusions and its possible association with shorter disease-free survival in advanced stage of breast carcinoma suggest a possible role in immune response evasion in some tumors.

[Determination and significance of interleukin-16 in tuberculous and malignant pleural effusion]

OBJECTIVE

Interleukin-16 (IL-16) is a chemoattractant of CD4+ lymphocytes, and it has been implicated in the pathogenesis of various inflammatory diseases. The aim of the present study was to measure IL-16 in pleural effusions caused by tuberculosis and malignancy and its relationship with cell and differential counts as well as lymphocyte subsets.

METHODS

Pleural effusion and venous blood samples were collected from 32 patients with tuberculous pleuritis and 30 lung cancer patients with malignant effusion. Analysis of pleural effusion for total leukocytes and cell differentials of leukocytes was performed. Three-color flow cytometry was performed to determine T lymphocyte subsets in cell pellets of pleural effusion. The concentration of IL-16 in cell-free supernatants of pleural effusion and sera was measured by a sandwich enzyme-linked immunosorbent assay.

RESULTS

In all the studied patients, the level of IL-16 was significantly higher in pleural effusion than in serum. The levels of IL-16 were significantly higher in tuberculous than in malignant effusions. In pleural effusion, positive correlations were found between the IL-16 levels and total cell counts, lymphocytes, CD3+ T cells, as well as CD4+ T cells.

CONCLUSIONS

Compared to malignant pleural effusion, IL-16 appeared to be increased in tuberculous pleural effusion. The pleural effusion IL-16 levels were positively related to the numbers of CD4+ T cells, suggesting that IL-16 might be capable of inducing CD4+ T cell infiltration into pleural space.

T-helper type 1/T-helper type 2 balance in malignant pleural effusions compared to tuberculous pleural effusions

STUDY OBJECTIVES

Malignant and tuberculous pleurisies are two major causes of lymphocyte-dominant pleurisy. Several studies have already reported that tuberculous pleurisy is a T-helper type 1(Th1)-dominant disease. In this study, we sought to examine the Th1/T-helper type 2 (Th2) balance, especially focusing on the polarizing status of T-cells to Th1/Th2 in malignant pleural effusions by measuring cytokines in pleural effusions and by evaluating the polarizing status of T-cells on the point of stimulation with interleukin (IL)-12 and/or IL-18. Furthermore, we evaluated inhibitors of interferon (IFN)-gamma production in effusions to rule out the possibility of direct inhibition of T-cell polarization.

PATIENTS

Effusion samples were collected from 19 patients with malignant pleurisy caused by lung cancer and from 7 patients with tuberculous pleurisy.

MEASUREMENTS

Concentrations of pleural fluid IFN-gamma, IL-12, and IL-4 were measured. IFN-gamma production of T-cells enriched from malignant pleural effusions in the presence of IL-12 and/or IL-18 was also examined. We further compared the inhibitory activity of malignant pleural effusions against IFN-gamma production and analyzed the expression of T-cell immunoglobulin mucin, mucin domain (Tim-3), a Th1-specific molecule in pleural fluid T-cells.

RESULTS

Although malignant pleural effusions showed low levels of Th1 and Th2 cytokines and ratios of IFN-gamma and IL-12 to IL-4 were low, isolated T-cells produced a significant level of IFN-gamma in the presence of IL-12 and IL-18. Soluble factors were not found to inhibit IFN-gamma production in malignant pleural effusions. In tuberculous pleural effusion, ratios of IFN-gamma and IL-12 to IL-4 were significantly higher, and T-cells showed the expression of Tim-3 messenger RNA.

CONCLUSIONS

We confirmed that T-cells in the malignant pleural effusions are mainly naïve or not definitely polarized to Th1. Moreover, malignant tumor does not actively distort the cytokine condition through production of soluble inhibitors within effusions. The present study indicates that antitumor immunity may be enhanced by restored IFN-gamma activity through combination of IL-12 and IL-18, and that it will lead to new therapies for malignant effusion.

CD4+CD25+ regulatory T lymphocytes in malignant pleural effusion

BACKGROUND

Active suppression by CD4(+)CD25(+) regulatory T lymphocytes plays an important role in the downregulation of T-cell responses to foreign and self-antigens.

OBJECTIVE

To analyze whether the CD4(+)CD25(+) regulatory T lymphocytes exist and function normally in malignant pleural effusion.

METHODS

The percentages of CD4(+)CD25(+) T lymphocytes in pleural effusion and peripheral blood from patients with lung cancer with malignant effusion, pleural lavage and peripheral blood from patients with lung cancer without effusion, and peripheral blood from healthy control subjects were determined by flow cytometry. The expressions of forkhead transcription factor Foxp3 and cytotoxic lymphocyte-associated antigen-4 were also examined. CD4(+)CD25(+) and CD4(+)CD25(-) T cells from pleural effusion and peripheral blood were isolated, and were cultured to observe the effects of CD4(+)CD25(+) cells on proliferation response of CD4(+)CD25(-) T cells in vitro.

MAIN RESULTS

There were increased numbers of CD4(+)CD25(+) T cells in malignant pleural effusion from patients with lung cancer compared with pleural lavage from patients with lung cancer without pleural effusion, and that these cells have constitutive high-level expression of Foxp3 and cytotoxic lymphocyte-associated antigen-4. Furthermore, CD4(+)CD25(+) T cells mediate potent inhibition of proliferation response of CD4(+)CD25(-) T cells, and anticytotoxic lymphocyte-associated antigen-4 monoclonal antibody could reduce the inhibitory activity of CD4(+)CD25(+) T cells.

CONCLUSIONS

The increased CD4(+)CD25(+) T cells found in malignant pleural effusion express high levels of Foxp3 transcription factor and potently suppress the proliferation of CD4(+)CD25(-) T cells, and cytotoxic lymphocyte-associated antigen-4 is involved in the suppressive activity of pleural CD4(+)CD25(+) T cells.

Regulatory T cells and cytokines in malignant pleural effusions secondary to mesothelioma and carcinoma

Immunotherapy against a variety of malignancies, including pleural-based malignancies, has shown promise in animal models and early human clinical trials, but successful efforts will need to address immunosuppressive factors of the tumor and host, particularly certain cytokines and CD4(+) CD25(+) regulatory T cells (Treg). Here, we evaluated the cellular and cytokine components of malignant pleural effusions from 44 patients with previously diagnosed mesothelioma, non-small cell lung cancer (NSCLC), or breast cancer and found significant differences in the immune profile of pleural effusions secondary to mesothelioma vs. carcinoma. Although a high prevalence of functionally suppressive CD4(+) CD25(+) T cells was found in carcinomatous pleural effusions, mesothelioma pleural effusions contained significantly fewer CD4(+) CD25(+) T cells. Activated CD8(+) T cells in pleural fluid were significantly more prevalent in mesothelioma than carcinoma. However, there is clear patient-to-patient variability and occasional mesothelioma patients with high percentages of CD4(+) CD25(+) pleural effusion T cells and low percentages of CD8(+) CD25(+) pleural effusion T cells can be identified. Mesothelioma pleural effusions contained the highest concentrations of the immunosuppressive cytokine transforming growth factor (TGF)-beta. Thus, the contribution of cellular and cytokine components of immunosuppression associated with malignant pleural effusions varies by tumor histology and by the individual patient. These results have implications for the development of immunotherapy directed to the malignant pleural space, and suggest the need to tailor immunotherapy to overcome immunosuppressive mechanisms in tumor environments.

HLA class I, NKG2D, and natural cytotoxicity receptors regulate multiple myeloma cell recognition by natural killer cells

The role of natural killer (NK) cells in multiple myeloma is not fully understood. Here, NK susceptibility of myeloma cells derived from distinct disease stages was evaluated in relation to major histocompatibility complex (MHC) class I, MHC class I chain-related protein A (MICA), MHC class I chain-related protein B (MICB), and UL16 binding protein (ULBP) expression. MHC class I molecules were hardly detectable on bone marrow cells of early-stage myeloma, while late-stage pleural effusion-derived cell lines showed a strong MHC class I expression. Conversely, a high MICA level was found on bone marrow myeloma cells, while it was low or not measurable on pleural effusion myeloma cells. The reciprocal surface expression of these molecules on bone marrow- and pleural effusion-derived cell was confirmed at mRNA levels. While bone marrow-derived myeloma cells were readily recognized by NK cells, pleural effusion-derived lines were resistant. NK protection of pleural effusion cells was MHC class I dependent. Receptor blocking experiments demonstrated that natural cytotoxicity receptor (NCR) and NK receptor member D of the lectin-like receptor family (NKG2D) were the key NK activating receptors for bone marrow-derived myeloma cell recognition. In ex vivo experiments patient's autologous fresh NK cells recognized bone marrow-derived myeloma cells. Our data support the hypothesis that NK cell cytotoxicity could sculpture myeloma and represents an important immune effector mechanism in controlling its intramedullary stages.

Simultaneous measurement of T-helper 1 cytokines in tuberculous pleural effusion

OBJECTIVE

Tuberculosis, the leading cause of death among infectious diseases worldwide, is a major cause of lymphocytic exudative pleural effusion. T-helper 1 cytokines, including interferon-gamma (IFN-gamma), interleukin (IL)-12p40 and IL-18 are predominantly associated with cell-mediated immune responses, and play an important role in immunity to Mycobacterium tuberculosis.

DESIGN

We studied 55 patients presenting with pleural effusion at the National Sanyo Hospital between April 2000 and September 2001 (42 men and 13 women; mean age 67 years). Twenty patients (36%) had tuberculous pleurisy, while 18 (33%) had malignant effusions and 17 (31%) had an effusion with another aetiology. Pleural fluid concentrations of IL-12p40 and IL-18 as well as IFN-gamma measured by enzyme-immunoassays.

RESULTS

Concentrations of all three cytokines were significantly higher in tuberculous than other pleural effusions. Significant correlations were evident between IFN-gamma and IL-12. We found particularly high concentrations of IL-12p40 and IFN-gamma in tuberculous patients with high fever.

CONCLUSION

The results indicate that T-helper 1 cytokines are involved in intrapulmonary cellular immune responses to M. tuberculosis, and suggest that the interactions between them may play an important role in the pathogenesis and severity of the pleural effusion. Understanding the development of this response may enhance our understanding of the pathogenesis of tuberculous pleural effusion and suggest new therapies.

Combined immunotherapy with intracavital injection of activated lymphocytes, monocyte-derived dendritic cells and low-dose OK-432 in patients with malignant effusion

We have conducted a pilot study with combined immunotherapy using autologous lymphocytes activated ex vivo and monocyte-derived dendritic cells in combination with low-dose OK-432, a streptococcal preparation, in five patients with peritoneal or pleural carcinomatosis who were resistant to standard chemotherapy. All patients were given 3 to 10 courses of the combined immunotherapy. No severe adverse reactions occurred. Effusion production was decreased in all of the patients. Significant decreases in tumor markers of both effusions and sera as well as effusion volume occurred in all of the patients. Cytological examinations revealed a marked decrease or disappearance of cancer cells in those effusions. Three patients showed increase in IFN-gamma levels in the effusions. The overall prognosis of the patients was acceptable and the mean survival time was more than 9 months. The locoregional immunotherapy seems to be encouraging in view of therapeutic modality in patients who are resistant to standard chemotherapy. Our study provides a new protocol for immunotherapy and warrants further phase I/II clinical study for chemo-resistant patients with malignant effusion.

Matrix metalloproteinases production in malignant pleural effusions after talc pleurodesis

In this study we have evaluated the modifications of matrix metalloproteinases (MMPs) in malignant pleural fluids taken from patients suffering from lung cancer and treated with intrapleural talc instillation to induce pleurodesis. Furthermore, we have analysed the variations of some inflammatory mediators (C-reactive protein, alpha-1 antitrypsin) and of a protein (plasminogen) involved in MMP activation. In all patients the clinical improvement after talc pleurodesis was followed by a reduction in MMP-1, TIMP-1, C-reactive protein, alpha-1 antitrypsin and plasminogen activity. Furthermore, MMP-9 levels were variable; in fact, in some patients they were high at the beginning of treatment, in others they increased a few days after pleurodesis induction. These inhibitory effects of talc on MMP-1 and inflammatory mediators associated with the reduction of pleural effusion could constitute an effective means to evaluate the evolution of the treatment.

Analysis of the immunological microenvironment at the tumor site in patients with non-small cell lung cancer

BACKGROUND AND AIMS

Inactivation of tumor-infiltrating lymphocytes by immunomodulating cytokines shed by tumor cells into the tumor local microenvironment might be a potential escape strategy of various tumors from immune-immediate killing. Here, we provide an analysis of the cytokine profile at the tumor site in patients with non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Using in situ hybridization (ISH), we determined the mRNA expression in lymphocytes and tumor cells for IL-2, INF-gamma, IL-12 (p40), IL-18, IL-4, IL-10, TGF-beta1, IL-1, IL-3, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF), TNF-alpha, and TGF-alpha in five fresh pleural effusion samples and 18 tumor tissue samples of patients with NSCLC.

RESULTS

In pleural effusion as well as in tumor tissue of NSCLC patients, the mRNA expression of IL-4, IL-10, TGF-alpha, and TGF-beta1 was significantly higher than that of IL-2, IL-12, IL-18 and INF-gamma. In contrast, the analysis of tuberculosis pleural effusion samples revealed lower mRNA levels for all cytokines and did not show any significant difference among them.

CONCLUSION

The predominant mRNA expression of type II and immunosuppressive cytokines in pleural effusion and tumor tissue of NSCLC patients mirrors an immunosuppressive state in the immunological microenvironment. The present study may, therefore, help to elucidate mechanisms of tumor escape and contribute to the development of an effective immunomodulatory treatment of NSCLC.

Elevated serum cytokine levels in mesothelioma patients who have undergone pleurectomy or extrapleural pneumonectomy and adjuvant intraoperative photodynamic therapy

Patients treated on a Phase-I clinical trial of photodynamic therapy (PDT) developed a systemic capillary leak syndrome that constituted the dose-limiting toxicity. We examined serum samples from patients treated at the maximally tolerated dose level for evidence of a systemic, cytokine-mediated inflammatory response. Patients underwent pleurectomy or extrapleural pneumonectomy (EPP) followed by intraoperative PDT of the thorax using Foscan at a dose of 0.1 mg/kg 6 days before surgery and 652 nm red light at a dose of 10 J/cm2. Levels of interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-6, IL-8, IL-10 and IL-12 were assayed before Foscan administration; after anesthetic induction, surgical resection and light delivery; in postoperative recovery and the day after the surgery. Of the analyzed patients, eight underwent a pleurectomy and one an EPP followed by PDT. IFN-gamma, TNF-alpha and IL-12 showed no elevation, but IL-1beta, IL-6, IL-8 and IL-10 levels were elevated after surgery and PDT. IL-1beta showed a statistically significant variation from baseline after surgery and IL-6, after PDT. The results suggest a systemically mediated inflammatory response resulting from thoracic surgery followed by PDT. Further investigation of specific mechanisms is warranted.

Expression of TCR-zeta chain and apoptosis in subpopulations of tumor-associated lymphocytes (TALs) from malignant pleural effusions

Malignant effusions in serous cavities represent suspension of tumors and inflammatory cells and therefore present an attractive model for studying tumor-host interactions. T cell functional ability is linked to proper signal transduction via T cell receptor (TCR-CD3 complex), especially its zeta chain. The latter has been found to be often depressed in malignancy. Aim of this study was to assess alterations of zeta chain expression and its relation to apoptosis of T lymphocytes. T lymphocytes obtained from pleural effusions of 20 cancer patients and 9 patients with nonmalignant effusions serving as a control were studied. The analysis was performed using flow cytometry combining CD3, CD 4, CD8, CD 16/56, TCR-zeta and TUNEL reaction. In the control group, T lymphocytes obtained from pure lymphocyte effusions had constantly high level of zeta chain while those from malignant pleural effusions had a decreased zeta chain expression. Lymphocytes with low zeta chain expression were the main subpopulation of T cells undergoing apoptosis.

Serum anti-p53 autoantibodies in pleural malignant mesothelioma, lung cancer and non-neoplastic lung diseases

Alterations of the p53 gene may lead to the production of detectable autoantibodies (p53-Abs) in cancer patients. In order to evaluate the association of p53-Abs with pleuropulmonary diseases, four groups of subjects were analyzed by ELISA for serum p53-Abs, in the framework of a molecular epidemiologic study. Two of 30 pleural malignant mesothelioma patients (MM; 6.7%) and 8/48 lung cancer patients (LC; 16.7%) were seropositive, while all 51 healthy controls (HC) were negative. Two of 55 (3.6%) at-risk controls (RC) with non-malignant respiratory diseases were positive and were not subsequently diagnosed any cancer. The difference was statistically significant between LC and RC or HC (P = 0.01), but not between MM and any other group. No correlation was found with age, sex, cancer stage or histology, cigarette smoking or occupational exposure. A longer survival (not significant) was shown in seropositive LC but not in MM. p53 expression in tumor tissue was also evaluated in a subgroup of MM. In conclusion, the presence of detectable p53-Abs in serum was associated in a statistically significant proportion of cases with LC but only occasionally with MM. The longer survival among positive LC patients and the presence of two seropositive among patients with non-neoplastic respiratory diseases should be further investigated.