Differential expression of CD44 splice variants in malignant and benign pleural effusions

Expression of CD44 isoform that contains variant exons (v1-v10) has been implicated in tumor progression and metastasis. Especially, CD44 isoform containing v6 (CD44v6) and that containing v7 (CD44v7) were shown to confer full metastatic behavior on tumor cells. We examined the expression of CD44v6 and CD44v7 in malignant pleural effusions (13 lung cancers and 4 non-lung cancers) and in benign pleural effusions (7 tuberculosis and 3 pneumonia) with Southern blot analysis of reverse transcription (RT)-polymerase chain reaction (PCR) products. CD44v6 was expressed not only in malignant pleural effusions (12 of 13 lung cancers and 4 of 4 non-lung cancers), but also in benign pleural effusions(9/10). In contrast, although expression of CD44v7 was found in most malignant pleural effusions (12 of 13 lung cancers and 4 of 4 non-lung cancers), it was found in only a few cases of benign pleural effusions. These results suggest that the expression of CD44v7 may be correlated with a tumor-specific event such as metastasis or dissemination in malignant pleural effusion, while no such correlation can be found with CD44v6.

Elevation of interleukin-10 levels in malignant pleural effusion

STUDY OBJECTIVE

Human immunity has been found to have two major components, cellular and humoral immunity. T-helper type 1 (Th1) pathway favors cellular immunity and Th2 pathway favors humoral immunity. Early determination toward Th1 and Th2 cells in the immune response is dependent on the balance between interleukin-12 (IL-12), which favors Th1 responses, and IL-4, which favors Th2 responses. IL-2 and interferon-gamma (IFN-gamma) are produced in the Th1 pathway, and IL-4 and IL-10 are produced in the Th2 pathway. Lack of cellular immunity, IL-2, and IFN-gamma had been reported in malignant pleural effusions. However, to our knowledge, there are no previous reports on other cytokine components involving Th1 or Th2 pathway. The present study was designed to answer these questions.

DESIGN

Cytokine levels in peripheral blood and pleural fluid of 21 patients with malignant pleural effusion, including IL-4, IL-10, and IL-12, were analyzed with enzyme-linked immunosorbent assays. Lymphocyte subpopulations of peripheral blood and pleural effusion were also studied by using flow cytometry.

MEASUREMENTS AND RESULTS

The results showed a significant increase in IL-10 level as compared with blood samples. IL-4 and IL-12 were below minimal detectable concentrations both in the blood and the effusion. The ratio of pleural helper T cells was significantly higher than in the blood (p = 0.0002). The ratio of pleural natural killer (NK) cells was significantly lower than in the blood (p = 0.0001). The ratio of pleural suppressor T cells was lower than blood with borderline significance (p = 0.0522). No significant change in B-lymphocyte ratio between blood and pleural effusion was found (p = 0.2471). There was no correlation between difference in IL-10 level and lymphocyte subpopulation of pleural effusion and blood samples.

CONCLUSIONS

Helper T-cell subpopulations were increased while NK and suppressor T-cell subpopulations were decreased in malignant pleural effusions. The decrease in NK cell subpopulations with elevated IL-10 and minimal IL-12 concentration in neoplastic pleural effusion would suggest the usage of IL-12 or antibody of IL-10 to improve local cellular immunity. Further study is needed.

Soluble interleukin-6 receptor levels in pleural effusions

Generation of soluble cytokine receptors is a general phenomenon, and the roles of several such receptors have been investigated in clinical settings. Unlike other soluble cytokine receptors, soluble interleukin-6 receptor (sIL-6R) can act as an agonist and thus is implicated as an important modulator in the acute-phase reaction of prolonged inflammation. The purpose of the present study was to determine the roles of pleural sIL-6R in both differential diagnosis of pleural diseases and in the induction of acute-phase protein. Specific sandwich enzyme-linked immunosorbent assays were used to determine sIL-6R and IL-6 in 19 tuberculous, 48 malignant and 10 transudative effusions. Although IL-6 levels in pleural effusions were strikingly different, no significant differences in pleural sIL-6R levels were found between the groups. Pleural levels of IL-6 were invariably much higher, whereas those of SIL-6R were invariably lower than serum levels. Furthermore, IL-6, but not sIL-6R, levels in effusions correlated significantly with serum C-reactive protein levels. These results suggest that: (1) pleural levels of sIL-6R are not increased even in strong inflammation such as tuberculous pleurisy, nor significantly different among pleural diseases; and (2) the local levels of sIL-6R are not as important as expected for the induction of acute-phase proteins in patients with pleural diseases.

Interleukin-1 receptor antagonist in pleural effusion due to inflammatory and malignant lung disease

Interleukin (IL)-1 is a key cytokine in inflammatory reactions. To clarify the mechanism of inflammation in the pleural cavity, we investigated the contribution of IL-1 and its antagonism to inflammatory processes in the pleural cavity. Interleukin-1 receptor antagonist (IL-1Ra) levels as well as IL-1 beta and interferon-gamma (IFN-gamma) levels were measured by enzyme immunoassay in pleural effusions from 70 patients. Pleural macrophages were also examined as possible sources of these cytokines in 10 patients. IL-1Ra was detectable in 28 patients (40%) out of 70 patients with pleural effusions. Patients with tuberculosis had significantly higher IL-1Ra as well as IFN-gamma levels in pleural effusion than patients with lung cancer. Transudative pleural effusions had low or undetectable IL-IRa levels. On the other hand, IL-1 beta levels were low, except in cases of parapneumonic pleural effusion. Spontaneous production of IL-1Ra pleural macrophages was observed in six patients, and IL-4 significantly augmented its production. Although spontaneous production of IL-1 beta was observed in only two patients, pleural macrophages produced significant amounts of IL-1 beta in response to lipopolysaccharide in all 10 patients examined. These results suggest that interleukin-1 receptor antagonist regulates various reactions by interleukin-1 in pleural effusion, and that pleural macrophages may act in situ as a source of interleukin-1 receptor antagonist.

IL-8 in pleural effusion

Interleukin-8 (IL-8) is a recently described potent chemotactic factor that may be involved in the pathogenesis of pleural effusions. To understand the actual mechanisms mediating the inflammatory response, changes in cellular components and IL-8 level in pleural fluid of different aetiologies were evaluated. Thirty-four patients (19 male, 15 female) with a mean age of 46 +/- 22 years (range 16-92) were included in the study. Of these, 13 had tuberculous pleural effusion, seven had empyema/parapneumonic pleural effusion, and 14 had malignant pleural effusion (seven adenocarcinoma, three ovarian carcinoma, two lymphoma, one chronic myeloid leukaemia, and one small cell carcinoma) with positive cytology. Differential cell counts in the pleural fluid were obtained using cytocentrifuge preparations. The concentrations of IL-8 in pleural fluid were measured by the ELISA method. Interleukin-8 was detected in all 34 pleural fluid samples. The serum IL-8 level was analysed only in the empyema/parapneumonic pleural effusion group. The mean IL-8 levels of tuberculous, empyema/parapneumonic, and malignant pleural effusions were 1420 +/- 1049 pg ml-1, 4737 +/- 2297 pg ml-1, and 1574 +/- 1079 pg ml-1, respectively. The IL-8 levels in the empyema/parapneumonic group were significantly raised over malignant and tuberculous groups (P < 0.02). The mean pleural fluid neutrophil counts in tuberculous, empyema/parapneumonic and malignant pleural effusions were 315 +/- 575 cells mm-3, 11,136 +/- 12,452 cells mm-3, and 635 +/- 847 cells mm-3, respectively (P < 0.003). There was a significant positive correlation between pleural IL-8 levels and neutrophil counts (r = 0.46, P < 0.006). The levels of IL-8 in paired samples of serum and pleural fluid in the empyema/parapneumonic effusion group were compared, and the concentration of IL-8 was higher in the pleural effusion than serum (means, 4737 +/- 2297 pg ml-1 and 130.0 +/- 62.5 pg ml-1, respectively, P < 0.03). There was a significant negative correlation between IL-8 concentrations in serum and pleural fluid (r = -0.80, P < 0.03). This data suggests that production of IL-8 in pleural effusion may play a key role in initiation and maintenance of inflammatory reactions, especially in empyema/parapneumonic pleural effusions. It may offer the basis for introduction of novel anti-inflammatory agents in treatment.

Immunoglobulin gene rearrangement in T-cell-rich reactive pleural effusion of a patient with B-cell chronic lymphocytic leukemia

Pleural effusion in chronic lymphocytic leukemia (CLL) is a relatively rare phenomenon. We report a case of a pleural effusion associated with B-cell CLL but with predominantly reactive T lymphocytes in the effusion. A cell surface phenotype study showed that T lymphocytes predominated in the pleural effusion, although B lymphocytes were predominant in the peripheral blood. Genotypic analysis of the cells in the peripheral blood, bone marrow, lymph node, and pleural effusion showed the same rearrangement pattern of the immunoglobulin heavy chain genes consistent with a B-lymphocytic neoplasm (CLL). A pleural biopsy demonstrated diffuse infiltration of lymphoid cells. Most of the cells demonstrated T cell markers, although some cells revealed B cell markers by immunologic staining. These results suggested that the pleural involvement by B-CLL may have caused a reactive T-lymphocyte proliferation in the pleura and pleural effusion. To our knowledge, this is the first published case indicating that genotypic analysis of immunoglobulin heavy chain gene rearrangement may be useful in the diagnosis of a pleural effusion associated with B-cell CLL.

Diagnostic utility of thoracentesis for neutropenic children with cancer

Thoracentesis is a procedure often performed in children with pleural effusions to assist in diagnosis and management. Its safety and utility for immunocompromised patients with neutropenia (absolute neutrophil count, <1,500 polymorphonuclear leukocytes and band forms per microL) is unclear. We reviewed our experience over a 10-year period to evaluate the role of thoracentesis for neutropenic children with cancer who had pulmonary effusions of presumed infectious etiology. Twenty-two patients were identified, and 18 had absolute neutrophil counts of < or = 500/microL. Empirical antibiotics had been administered to 95% of these patients and antifungal agents to 72%. Two patients' cultures were positive for fungal organisms: Aspergillus terreus in one case and Candida albicans in the other. Both of these patients had been receiving antifungal therapy. Therapy was altered for these two patients plus one additional patient in whose pleural fluid tumor cells were unexpectedly found. Eight of the remaining 19 patients underwent another diagnostic procedure, yielding five additional diagnoses. In conclusion, thoracentesis is safe and should be considered as a diagnostic test for febrile neutropenic patients with pulmonary effusions of presumed infectious etiology, although more invasive tests may be warranted.

[Clinical effects and immunological analysis of intraabdominal and intrapleural injection of lentinan for malignant ascites and pleural effusion of gastric carcinoma]

Twenty-one patients with malignant peritoneal or pleural effusions of gastric carcinomas were treated with intracavitary injection of lentinan (LNT). LNT was injected at a dosage of 4 mg/week for 4 weeks. In total, fifteen (71%) of twenty-one patients demonstrated clinical responses. Toxicity caused a high fever in only one case. LAK and ATK activities induced from peritoneal exudate cells (PEC) after culture with autologous tumor and interleukin-2 were examined before and after LNT injection. ATK activity was augmented, but LAK activity was reduced after LNT injection. These results indicate that intracavitary injection of LNT is a useful treatment for malignant effusions, and that LNT augments the induction of cytotoxic T-lymphocytes.

[T cell receptor V beta repertoire of locoregional lymphocytes in malignant effusions]

We analyzed the T cell receptor (TCR) V beta repertoire of lymphocytes obtained from patients with malignant effusion treated by locoregional immunotherapy. Polymerase chain reaction using a panel of V beta subfamily specific oligonucleotide primers(V beta 1-20) was employed after reverse transcription of mRNA isolated from the locoregional cells. No major oligoclonality of TCR repertoire was observed in effusion lymphocytes before the treatment. The expression level of V beta 13.1 repertoire was significantly higher in effusion lymphocytes than in peripheral blood lymphocytes before treatment. V beta 20 gene expression increased significantly after locoregional administration of OK-432. It is suggested that TCR V beta 13.1 may be responsible for effusion lymphocytes and TCR V beta 20 for OK-432-related antigenic stimulus.

Tumor-associated lymphocytes (TAL) are competent to produce higher levels of cytokines in neoplastic pleural and peritoneal effusions than those found in sera and are able to release into culture higher levels of IL-2 and IL-6 than those released by PBMC

This work was designed to study the proliferative response of tumor-associated lymphocytes (TAL) from neoplastic effusions against autologous tumor cells and the immunophenotype pattern of TAL from neoplastic effusions and that of PBMC of the same patients. We also compared the serum levels of the cytokines interleukin (IL) 1 beta, 2 and 6, tumor necrosis factor-alpha (TNF alpha) and soluble IL-2 receptor (sIL-2R) with those present in neoplastic effusions of the same patients. Moreover, we examined the ability of TAL and peripheral blood mononuclear cells (PBMC) to produce and release the cytokines and sIL-2R and to express membrane CD25 following their stimulation with phytohemagglutinin (PHA) in vitro. Finally, we compared the cytokines/sIL-2R production and membrane CD25 expression by PHA-stimulated PBMC of the patients with neoplastic effusions with a series of 90 cancer patients without neoplastic effusions and 20 normal healthy subjects. Thirteen neoplastic pleural and eight peritoneal effusions were collected from 11 patients with primary lung cancer, 7 with primary epithelial ovarian cancer, 1 with breast cancer, 1 with pleural mesothelioma, and 1 with pancreatic cancer. The proliferative response of TAL from neoplastic effusions against autologous tumor cells was lower than the response to PHA, IL-2, and anti-CD3, but significant. The percentage distribution of CD3+ and CD8+ lymphocyte subpopulations was higher in peritoneal than in pleural effusions, while the CD16+ subset was higher in pleural than in peritoneal effusions. The percentage distribution of CD16+ was significantly lower in pleural effusions than in PBMC of patients with pleural effusions.(ABSTRACT TRUNCATED AT 250 WORDS)

Significance of epithelial membrane antigen in the work-up of problematic serous effusions

Differentiation of reactive and/or atypical mesothelial cells from malignant epithelial cells in serous effusions remains a frequent diagnostic problem. Since epithelial membrane antigen (EMA) positive malignant cells in serous effusions have been reported in almost all adenocarcinomas and most malignant mesotheliomas, immunoreactivity for EMA is felt to be less useful than other antibodies in the workup of problematic serous effusions. However, immunostaining of reactive and/or atypical benign mesothelial cells for EMA has not been well studied, with only a few series reporting either weak or negative staining for EMA. This study was undertaken to evaluate how often reactive and/or atypical appearing mesothelial cells stain positively for EMA. One hundred eighty serous effusions (115 pleural, 55 peritoneal, and 10 pericardial) from 123 females and 57 males ages 20 to 89 yr were evaluated in which an antibody panel including EMA was performed on cell blocks (141 cases), cytospins (36 cases), or both (3 cases). Of the 100 cytologically positive cases, EMA immunoreactivity was present in 97/100 (97%) cases. One EMA negative case suspicious for a metastatic renal cell carcinoma was lost to follow-up and not included in the analysis. The remaining three negative cases consisted of malignancies not expected to have EMA positive cells (small cell carcinoma, neuroblastoma, and synovial sarcoma). Therefore, EMA was positive in virtually 100% of the remaining malignant cases. In the 78 cytologically negative cases, EMA positivity was present in 3/78 (3.8%) cases. Clinical follow-up of up to 14 mo in these three cases revealed no evidence of malignancy.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical evaluation of CYFRA 21-1 in malignant pleural fluids

The diagnostic value of the novel tumor marker CYFRA 21-1 in malignant pleural fluid was assessed in comparison to carcinoembryonic antigen (CEA). CYFRA 21-1 and CEA were measured in pleural fluid obtained from patients with 108 malignant and benign diseases. The levels of pleural fluid CYFRA 21-1 in malignant diseases (median: 84.5 ng/ml) were statistically higher than those in benign diseases (median: 13.9 ng/ml; p < 0.01). The CYFRA 21-1 test was able to discriminate significantly between squamous cell lung cancer and pneumonia (p < 0.01), while pleural fluid CEA levels could not. Receiver operating characteristic (ROC) curve analysis showed that the CYFRA 21-1 test has an advantage over CEA because of its higher specificity. These results indicate that measurement of CYFRA 21-1 in pleural fluid is a new tool, in addition to cytologic examination, to discriminate between malignant and benign diseases.

Immunocytological analysis of the Tn associated antigen 83D4 in serous effusions from patients with cancer: comparison with Tn soluble glycoprotein

AIMS

To determine whether the monoclonal antibody (MoAb) 83D4, previously shown to be highly specific for carcinoma cells, can be used as an immunocytological marker to discriminate between benign and malignant cells in serous effusions; and to test for a correlation between expression of the antigen reacting with MoAb 83D4 on effusion cells and the amount of soluble 83D4 antigen in effusion fluids.

METHODS

Thirty three pleural and 23 peritoneal effusions from 56 cancer patients with metastatic disease were tested for the presence of Tn associated 83D4 antigen by immunocytochemical staining, and for the presence of soluble antigen in supernatants. The patients had undergone various chemotherapy and radiation therapy protocols.

RESULTS

As a result of the various types of treatment, the cytological characteristics of the cells were often modified and the antigenic epitopes may have been altered. Positive staining for 83D4 MoAb was obtained in 36 (97%) of the 37 malignant effusions, eight (73%) of 11 suspect effusions, and three (38%) of the eight apparently benign effusions (free of malignant cells). In these latter cases, cytological reassessment showed a few suspect cells in two cases. 83D4 soluble antigen was detected in 30 of 37 malignant effusions (81%), five of 11 suspected infusions (46%), and five of eight apparently benign effusions (63%).

CONCLUSIONS

Immunocytochemical staining with anti-83D4 antibody is useful for differentiating reactive or atypical mesothelial cells from epithelial cells, especially in breast cancer effusions.

[Comparison of complement activation between tuberculous and malignant pleuritis]

Complement activation products in pleural effusions were studied to clarify the causes of tuberculous and malignant pleuritis. Pleural SC5b-9, an activation product of complement common pathway, was significantly higher in tuberculous effusions than in malignant ones. In the tuberculous effusions, the levels of SC5b-9 and LDH (a marker of tissue damage) were significantly correlated, but in the malignant effusions these two values were not correlated. In the tuberculous effusions, SC5b-9 and Bb values were significantly correlated, but SC5b-9 and C4d were not, and nor were SC5b-9 and immune complex. In the malignant effusions, SC5b-9 and Bb values were low and were not significantly correlated. These results suggest that complement activation plays a significant role in tuberculous pleuritis, but not in malignant pleuritis.

[The significance of immune island appeared in pleural and peritoneal effusion]

Macrophage surrounded by transformed or untransformed lymphocytes is called immune island. Aimming at this problem, we made a survey of 120 pleural and peritoneal effusion smears with a variety of patients and discovered that this island appeared in 52 (43.3%) cases. The positive results existed in 11 of 14 (79%) cases with tuberculosis and 29 of 60 (48%) cases with malignant diseases. The average number of island on each positive smear (2.0cm x 2.5cm) is 59.6 +/- 12.8 in the former and 39.2 +/- 18.9 in the latter. The mechanism of this phenomenon may be due to the response to foreign stimulus from pathogenic and cancer antigen.

[The changes and clinical significance of interleukin 1 beta in pleural effusion]

An enzyme linked immunosorbent assay was set up by using anti-recombinant human interleukin 1 beta monoclonal antibodies. The interleukin 1 beta, anti-interleukin 1 beta autoantibody and interleukin 1 beta containing immune complex were detected in pleural effusion of 28 patients with bacterial infection cases pleurisy and 13 with lung cancer. The results showed that free interleukin 1 beta could be detectable in the early stage of pleurisy, and then transformed to the immune complex. The interleukin 1 beta containing immune complex were detectable in the pleeural effusions of all the 28 patients with pleurisy, but only two patients with lung cancer. The results suggested that this cytokine behaves differently in these two different kinds of diseases.

[The cytotoxicity of malignant pleural effusion lymphocytes and LAK cells against autologous tumor cells]

In malignant pleural effusion, lymphocytes (MPEL) and autologous tumor cells (ATC) were obtained by centrifugation on discontinuous density gradients from 16 patients with malignant pleural effusion. The cytotoxicity of MPEL against ATC were compared with that of peripheral blood lymphocytes (PBL). It was demonstrated that the results for separation with 100%: 60% Ficoll-Hypaque which formed a discontinuous density gradients were the best in three sets of discontinuous density gradients. The cytotoxicity of PBL was higher than that of MPEL (P < 0.001), but the cytotoxicity and expansion of MPEL-activated by rIL2 was much higher than that of PBL-activated by rIL2 (LAK cells) (P < 0.001). This shows that local immune reaction within pleural cavity of patients with malignant pleural effusion was in the state of suppression, but the state could be improved by using rIL2. Therefore, we consider that MPEL could be the better effector cells than LAK cells in tumor adoptive immunotherapy.

Intrapleural Corynebacterium parvum for recurrent malignant pleural effusions

Twenty-two consecutive patients with malignant pleural effusions (MPE) were treated with intrapleural Corynebacterium parvum (CBP) associated with parenteral methylprednisolone (MP) to determine its effectiveness and the frequency and nature of adverse reactions. After thoracentesis, 7 mg of CBP (Coparvax Wellcome) in 20 ml of saline were injected into the pleural cavity. On the day of treatment, the patients were given 1 mg/kg i.m. of MP 30 min before thoracentesis. The effectiveness of pleurodesis was assessed as follows: (1) complete response (CR; total resolution of pleural effusion after 3 injections of CBP at the most); (2) partial response (PR; formation of asymptomatic loculated effusion). In 5 patients leukocytes, lymphocytes and monocytes were determined in pleural fluid (PF) and in blood (B) collected before and 7 days after CBP treatment. Two patients were unevaluable. Of 20 evaluable patients, 18 (90%) had a CR and 2 patients (10%) had a PR. Eleven of 22 patients (50%) had a fever. Three patients had prolonged and/or high fever. Seven of 22 patients (32%) had mild chest pain. None of the patients presented other side effects. Twelve of 21 patients (57.1%) had a PF pH > or = 7.30; 2 of these died a few days after the treatment, and 10 had favorable responses. The other 9 patients had a PF pH < 7.30: all had favorable responses. The leukocytes, the lymphocyte subsets, the monocytes, the NK lymphocytes, and their PF/B ratios did not differ significantly before and after CBP treatment. Our study confirms that intrapleural CBP is an effective and simple method to control MPE.(ABSTRACT TRUNCATED AT 250 WORDS)

[Diagnostic value of tissue polypeptide antigen in pleural effusions with malignant pleural mesothelioma]

There are no known tumor makers of malignant pleural mesothelioma. We measured the concentration of TPA in the pleural effusions from patients with malignant pleural mesothelioma and from patients with other pleural diseases, evaluate its clinical usefulness. The concentration of TPA was more than 7,000 U/l (mean: 18,600 +/- 9,867 U/l, n = 5) in all patients with malignant pleural mesothelioma, but it was less than 4,000 U/l in those with benign asbestos pleurisy and other benign pleural effusion (benign asbestos pleurisy 1,598 +/- 570, n = 5: p < 0.01, tuberculous pleurisy 1.37 +/- 759, n = 11: p < 0.01, others 2,497 +/- 2,152 n = 3: p < 0.05). The concentration of TPA in the pleural effusions was not significantly different between malignant pleural mesothelioma and lung cancer (12,287 +/- 17,070 U/l). However, in all patients with lung cancer and high TPA concentrations, cytologically malignant cells were detected in the pleural effusions. TPA was high in all five patients with malignant pleural mesothelioma, but cytologically malignant cells were detected in only one patient. Only in malignant pleural mesothelioma (not in other benign disease or in lung cancer) was the concentration of TPA more than 4,000 U/l, and no evidence of malignancy was obtained by cytological methods. These findings suggest that assessing TPA in the pleural effusion might contribute to the diagnosis of malignant pleural mesothelioma.

Transforming growth factor-beta 1 (TGF-beta 1)- and beta 2-like activities in malignant pleural effusions caused by malignant mesothelioma or primary lung cancer

We investigated the levels of TGF-beta in malignant pleural effusions (MPE) caused by malignant mesothelioma (MESO) or primary lung cancer. TGF-beta levels in MPE caused by MESO were 283.9 +/- 219.2 pm (mean +/- s.d.) and were three to six times higher than those due to primary lung cancers (P < 0.01 or P < 0.05). We also evaluated TGF-beta 1- and beta 2-like activities in MPE using specific polyclonal antibodies. Although TGF-beta 1-like activity could be detected in all cases, TGF-beta 2-like activities were detected in five of seven in MESO and in a few cases with primary lung cancer. These results demonstrate that the levels of total TGF-beta and TGF-beta 2-like activity may be clinically useful to differentiate MESO from primary lung cancer. Our data also suggest that TGF-beta may help further characterize the clinical features of MESO.

Mononuclear cells in exudative malignant pleural effusions. Characterization of pleural phagocytic cells

The aims of this study were to develop a methodology for the isolation of highly enriched mononuclear phagocyte populations from exudative malignant pleural effusions (EMPE) and to characterize the phenotype and functional properties of these cells. Pleural effusion mononuclear cells (PEMC) were isolated by Ficoll centrifugation of EMPE and transudative pleural effusions and allowed to adhere to plastic for 1 h to obtain a pleural effusion mononuclear adherent cell (PEMAC) fraction. Only 66.0 +/- 4.2 percent of PEMAC ingested latex particles, indicating that a significant proportion of PEMAC were not phagocytic cells. Latex-positive PEMAC had the morphologic appearance of macrophages and stained positive (97.3 +/- 4.3 percent) with the anti-CD68 monoclonal antibody (MoAb), specific for macrophages. Conversely, latex-negative PEMAC (34.0 +/- 4.1 percent of PEMAC) did not react with the anti-CD68 MoAb and stained with anti-CD3 (34.7 +/- 10.7 percent) and anticytokeratin (50.5 +/- 16.4 percent) MoAbs, indicating that T cells and mesothelial cells were present in the PEMAC fraction. To improve the purification of pleural macrophages, PEMAC were cultured for an additional 18 h and the cells that remained adherent after this period constituted the firmly adherent mononuclear cell (FAMC) fraction. Nearly 90 percent of FAMC ingested latex particles and were CD68-positive. Virtually all FAMC were CD3-negative and cytokeratin-negative. Similar percentages of FAMC from EMPE and transudative effusions expressed the monocyte-lineage markers CD11b and CD14, suggesting that the proportion of monocyte-like mononuclear phagocytes in the pleural space is not increased during local tumor-associated inflammatory responses. The FAMC from EMPE (1) expressed HLA-DR antigens, (2) released interleukin 1 (IL-1) beta and tumor necrosis factor (TNF) alpha, and (3) stimulated allogeneic T-lymphocyte proliferation. The results of this study suggest that pleural mononuclear phagocytes may be involved in tumor-associated inflammatory reactions in the pleural compartment by stimulating the proliferation of other inflammatory cells and by releasing inflammatory cytokines.

Immunocytochemical differentiation of reactive mesothelial cells and adenocarcinoma cells in serous effusions with the use of carcinoembryonic antigen and fibronectin

Ninety effusions from patients with breast and ovarian cancer were studied cytologically and classified as benign, suspicious or malignant, and the same samples were studied for carcinoembryonic antigen (CEA) and fibronectin (F) immunostaining. The combination F positive/CEA negative was found to have 100% specificity and 92.3% sensitivity in patients with benign or reactive effusions, and F negative/CEA positive 85.7% specificity and 80.7% sensitivity for malignancy. Immunostaining provides valuable supplementary information in cytologically suspicious patients. In the presence of F negative/CEA negative effusions, it is probable that insufficient cellular material is present for either a cytologic or immunostaining diagnosis.

Tumor specific cytolysis by tumor infiltrating lymphocytes in breast cancer

BACKGROUND

In vitro studies have demonstrated that exposure of tumor infiltrating lymphocytes (TIL) to human recombinant interleukin-2 (rIL-2) will generate activated T-lymphocytes with major histocompatibility complex (MHC)-restricted and non-MHC-restricted cytotoxicity toward a panel of tumor target cells. In melanoma and ovarian carcinoma, TIL display MHC-restricted and autologous tumor-specific cytotoxicity. Such tumor-reactive cytotoxic T-lymphocytes (CTL) represent important material for understanding cellular immunity in cancer and developing specific immunotherapeutic approaches in melanoma and ovarian cancer. In breast cancer, some TIL have been demonstrated to secrete cytokines upon interaction with autologous tumor cells, indicating that autologous tumor-reactive lymphocytes may also exist among TIL in breast cancer. Therefore, the authors conducted a study to investigate the cytotoxic profile of rIL-2-activated lymphocytes in breast cancer.

METHODS

Lymphocytes were isolated from primary solid tumors (TIL) of breast carcinomas (10 patients) and from peritoneal effusions (effusion-associated mononuclear cells [EAMNC]) from 2 patients with newly diagnosed metastatic breast carcinoma. Tumor infiltrating lymphocytes or EAMNC were cultured with rIL-2 in long term cultures whereby their expansion index, phenotype, and cytotoxic potential were studied.

RESULTS

Both TIL and EAMNC proliferated by greater than 300-fold (370-3650; mean, 1656) after 23-82 days in cultures containing mixtures of TIL or EAMNC, autologous tumor cells, and rIL-2. By fluorescence analysis, freshly isolated TIL and EAMNC were found to consist of 77.5 plus or minus 10.7% CD3+ T-cells, 33.2 plus or minus 8.9% CD4+, and 47.2 plus or minus 16.8% CD8+ cells. Their CD4 to CD8 ratio was 0.70. After expansion of lymphocytes with rIL-2 in the majority of patients (9 of 12), CD3+CD8+ T-lymphocytes were present in greater numbers than CD3+CD4+ T-lymphocytes. Recombinant interleukin-2-activated CD3+CD8+ cells exhibited preferential cytolytic activity against autologous tumor cells. The cytolytic activity of CD3+CD8+ cells was inhibited either by anti-T-cell receptor (TCR)-alpha/-beta and anti-CD3 monoclonal antibodies (MoAb) or after pretreatment of tumor target cells with MoAb against the class I MHC antigens. Recombinant interleukin-2-activated CD3+CD4+ cells demonstrated potent cytolytic activity against both autologous and allogeneic tumor cells. CD3+CD8+ T-cell clones isolated from representative TIL exhibited preferential autologous tumor-specific cytotoxicity whereas the cytolytic activity of CD3+CD4+ T-cell clones was mostly (12 of 14 clones) nonrestricted to the autologous tumor.

CONCLUSIONS

To the authors' knowledge, this is the first report to demonstrate that TIL from primary tumors of breast carcinomas and EAMNC from metastatic disease can be propagated in large numbers in vitro with rIL-2 while retaining autologous tumor specific and MHC-restricted CTL activity. These findings may be of importance to ongoing clinical trials using TIL or EAMNC in the immunotherapy of patients with advanced breast cancer.

Pleural effusion in multiple myeloma

We report the first case of IgA-kappa multiple myeloma presenting as a myelomatous and eosinophilic pleural effusion with increased adenosine deaminase activity. In a review of the literature, 80 percent of myelomatous pleural effusions are due to IgA multiple myeloma.

Recruitment of inflammatory cells to the pleural space. Chemotactic cytokines, IL-8, and monocyte chemotactic peptide-1 in human pleural fluids

Pleural effusions secondary to various diseases are associated with the presence of different inflammatory cells. The role of selective chemotactic cytokines in the recruitment of phagocytes to the pleural space is unclear. IL-8 and monocyte chemotactic peptide-1 (MCP-1) are recently described cytokines that are chemotactic for neutrophils and monocytes, respectively. We prospectively studied 63 patients, using strictly defined criteria for their selection. IL-8 concentrations were elevated in both empyema fluid (9.15 +/- 0.89 ng/ml) and parapneumonic effusions (4.7 +/- 0.697 ng/ml) when compared with pleural effusions secondary to other diseases. IL-8 levels were higher in empyema fluid than in parapneumonic effusions (p = 0.01). There was a significant correlation between IL-8 levels and the total numbers of neutrophils in empyema fluids (r = 0.80). Chemotactic activity for neutrophils was elevated in empyema fluid and the addition of IL-8 neutralizing serum decreased bioactivity by 32.22%. Malignant pleural effusions had the highest levels of MCP-1 (12.0 +/- 3.7 ng/ml) when compared with others. Cytology-positive pleural fluids (n = 10) had a higher level of MCP-1 than cytology-negative effusions (p = < 0.05). Malignant pleural fluid MCP-1 levels correlated (r = 0.70) with the absolute number of monocytes in the pleural fluid. Neutralization of monocyte chemotactic activity of malignant pleural fluid by specific neutralizing serum caused a 70.3% inhibition of bioactivity. Immunohistochemical staining of malignant pleural fluid localized antigenic MCP-1 to malignant cells. We conclude that both IL-8 and MCP-1 play major but not exclusive roles in the recruitment of neutrophils and monocytes from the vascular compartment to the pleural space.

The intrapleural administration of recombinant interleukin-2 (rIL-2) to patients with malignant pleural effusion: clinical trials

Recombinant IL-2 (rIL-2) was administered intrapleurally according to an original protocol to 11 patients with malignant pleural effusion, 7 of whom suffered from breast cancer and 4 from esophageal cancer. The pleural effusions either disappeared or decreased roentgenographically, and malignant cells disappeared from all 13 pleural cavities in the 11 patients, confirming the validity of this therapy to be 100%. The mean survival time from the initial administration of rIL-2 was 15.9 months. We ensured that the concentration of IL-2 in the effusion was maintained at a high level for a sufficient period of time, and that the lymphokine-activated killer (LAK) activity of lymphocytes in the effusion was augmented. Fever, eosinophilia, and a transient increase in the pleural effusion were the main side effects, but the symptoms were temporary and not serious. The results of this study therefore suggest the efficacy of intrapleural rIL-2 for patients with malignant pleural effusion.

Induction of cytolytic activity of lymphocytes from carcinomatous pleural effusion by IL-2 and autologous tumor cells

We established a cell line (STKM-1) from tumor cells obtained from carcinomatous pleural effusion of a gastric cancer patient. The lymphocytes separated from her peripheral blood or pleural effusion were cryopreserved and immunological experiments were performed after the establishment of the cell line. They were treated with IL-2 or with both IL-2 and mitomycin C (MMC)-treated autologous STKM-1 cells. The cytolytic activity against STKM-1 cells was elevated in lymphocytes cultured with IL-2, and was more prominently augmented in lymphocytes cultured with both IL-2 and MMC-treated STKM-1 cells. The elevation in cytolytic activity was more marked with pleural effusion lymphocytes than with the peripheral blood lymphocytes. The results suggest that the lymphocytes obtained from the pleural effusion would be an excellent source for adoptive immunotherapy.

Induction of inflammatory cytokines in the pleural effusion of cancer patients after the administration of an immunomodulator, OK-432: role of IL-8 for neutrophil infiltration

When OK-432, a well-known streptococcal preparation for an anti-tumour drug, was administered into the pleural cavity of patients with malignant pleurisy, a rapid and prominent leukocytosis, predominantly consisting of neutrophils, was observed in the cavity. Neutrophil infiltration usually peaked 6-9 h after OK-432 administration, and levelled down after 24 h. Prior to the neutrophil accumulation, transient but marked elevation of various inflammatory cytokine levels including IL-1 beta, TNF-alpha, IL-8 and G-CSF was observed. In particular, IL-8 levels increased more than 10-fold, while GM-CSF did not change significantly. A good correlation between IL-8 levels and neutrophil chemotactic response was observed particularly during 0-3 h. Specific neutralization or removal of IL-8 by antibody column abrogated half of the neutrophil chemotaxis, while neutralization of C5a removed around 40%. Sequential removal of IL-8 and C5a abrogated totally 80% of chemotaxis, confirming that these two factors are mostly responsible for the neutrophil chemotaxis in the pleural fluids. These results have suggested that rapid neutrophil infiltration induced by OK-432 in vivo is ascribable largely to IL-8 and in part to C5a.

Phenotypes and lymphokine-activated killer activity of pleural cavity lymphocytes of lung cancer patients without malignant effusion

We examined the phenotypes of lymphocytes in the pleural cavity of 23 lung cancer patients without malignant effusion. The ability of those lymphocytes to develop lymphokine-activated killer (LAK) activity and the regulation of LAK by pleural cavity macrophages were also compared with their counterparts in the peripheral blood. Mononuclear cells (MNC) were obtained simultaneously from the blood and by lavage of the pleural cavity of patients with lung cancer. The proportion of the T-cell subset of HLA-DR+ cells was significantly higher in the pleural cavity than in the peripheral blood, but the proportions of CD3+ and CD8+ cells in the pleural cavity were similar to the corresponding proportions in the blood. The proportions of CD4+ and CD16+ cells were lower in the pleural cavity than in the blood. The LAK activity could be developed by MNC from the pleural cavity following incubation with interleukin 2 (IL-2), but the LAK activity of pleural cavity MNC was significantly less than that of peripheral MNC. Pleural cavity lymphocytes alone also developed LAK activity following incubation with IL-2. Pleural macrophages from the patients were regulated to augment in vitro induction of LAK activity by IL-2 from autologous blood lymphocytes and pleural cavity lymphocytes. Lymphocytes in the pleural cavity without malignant pleural effusion could be developed by LAK activity and this activity was augmented by pleural cavity macrophages. The LAK activity developed by pleural cavity lymphocytes was significantly lower than that developed by peripheral blood lymphocytes. However, they can change their population to include cells with higher activities on exposure to IL-2 against the invasion of lung cancer cells into the pleural cavity. Thus, the population of lymphocytes in the pleural cavity of patients with lung cancer without malignant pleural effusion was different from that in malignant pleural effusion.

Effect of storage time on the analysis of lymphocyte subpopulations in pleural effusions

It is not known how long cell surface antigens can be detected on lymphocytes in pleural effusions. Therefore, the lymphocyte subpopulations of 15 native pleural effusions were analyzed after different storage times, at either 4 degrees C or room temperature, using the peroxidase-antiperoxidase adhesive slide assay. No significant differences in the lymphocyte subpopulations were observed after one day of storage under both conditions, although the immunoreactivity with CD4 was poor in the majority of cases stored at 4 degrees C and in two cases stored at room temperature. After three days of storage at 4 degrees C and after four days of storage at room temperature, a marked decrease in lymphocytes attached to the slides was observed. Immunoreactivity with CD8, CD20, CD45 and HLA-1 was well preserved, also, after one week of storage. Reactivity with CD3 was weak or poor after three days of storage in some cases. It is important to recognize that the preservation of the immunoreactivity of lymphocytes is dependent not only on the nutritive quality of pleural fluids but also on the cell preparation method.

Interferon instillation for malignant pleural effusions

BACKGROUND

Malignant pleural effusions can be managed in various ways including instillation of antineoplastic agents. Instillations of alfa interferon-2b (IFN-alpha 2b) have been utilized with success in various loco-regional malignancies suggesting a possible role in management of pleural effusions. This trial was designed to evaluate the tolerability and efficacy of intrapleural IFN-alpha 2b instillations in this situation.

PATIENTS AND METHODS

Twenty-three patients with cytologically proven malignant pleural effusions were given IFN-alpha 2b 50 x 10(6) units in 50 ml normal saline (NS) by intrapleural instillation after partial or complete clearance of effusions by percutaneous aspiration or chest tube drainage. For persistent or recurrent effusions, instillations were repeated with dose escalation to 75 x 10(6) units. Patients were assessed and monitored by regular clinical examinations, chest radiographs, biochemical and hematological parameters and assays of lymphocyte subpopulations until relapse or death in each case.

RESULTS

Fourteen of 20 evaluable patients (70%) had responses lasting for a median of 6 months; there were 8 complete responses (CR) and 6 partial responses (PR). In 6 CR patients the effusions did not recur after the first instillation. In 2 of 6 other patients, the second instillation was successful in inducing CR. Intrapleural instillation of IFN-alpha 2b was well tolerated, no grade 4 toxicities were encountered. There were no significant effects on any of the studied parameters at the initial dose level; however, grade 3 neutropenia occurred with the escalated dose. The most common toxicity was flu-like syndrome, after 70% of the instillations.

CONCLUSIONS

Intrapleural instillation of IFN-alpha 2b produced an encouraging response rate without significant toxicities. This approach may warrant additional phase II or phase III comparative clinical studies.

The characterization of peritoneal and pleural exudate cells from malignant effusions

The immune function of peripheral blood cells and cells from the pleural and abdominal effusions of patients with advanced cancer was compared to that of peripheral blood cells from controls. The parameters examined included lymphocyte subsets, natural killer (NK) cell activity, and anti-Daudi and lymphokine-activated killer (LAK) cell activity. The percentage of CD4+ pleural and peritoneal exudate cells (PEC) was significantly higher than the percentage of peripheral blood mononuclear cells (PBMC) in the patients. The percentage of CD8+CD11+ PEC and PBMC, being the suppressor T-cells, of the patients was increased compared with controls, while the percentage of CD8+CD11- PEC, being the cytotoxic T-cells, was identical to the PBMC of both patients and controls. The NK activity of PEC was significantly lower than that of PBMC in both patients and controls, and there was no correlation between the NK activity of PBMC and PEC. Although the anti-Daudi activity of PEC was markedly low, LAK cells with high activity could be induced by culture with interleukin-2 for 4 days. These results suggest that the immune function of cells in malignant effusions may be depressed due to a low population of cytotoxic T cells, low NK activity and increased suppressor T cells, while the local administration of interleukin-2 may induce LAK cells. Therefore, effective local immunotherapy for malignant effusions should not only augment effector cells, but also inhibit suppressor cells.

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.

Antigenic modulation of metastatic breast and ovary carcinoma cells by intracavitary injection of IFN-alpha

Antigenic modulation of major histocompatibility and tumour associated antigens was observed in neoplastic cells obtained from patients with pleural and abdominal effusions of breast and ovary carcinomas following a single intracavitary dose of 18 x 10(6) U recombinant IFN-alpha. This regimen resulted in antigenic modulation in seven out of 11 tested cases, suggesting a potential, although limited, responsiveness of at least a fraction of breast and ovary carcinoma cells to in situ biomodification with IFN-alpha.

IL-6 in malignant pleural effusions and its augmentation by intrapleural instillation of IL-2

The levels and activities of endogenous IL-6 in malignant pleural effusions due to lung cancer before and during daily intrapleural instillations of recombinant IL-2 were examined by enzyme immunoassay and bioassay using an IL-6-dependent murine hybridoma cell line MH60.BSF2. Before therapy, malignant pleural effusions contained various levels of IL-6. Daily intrapleural instillation of recombinant IL-2 for treatment of malignant pleurisy resulted in significant augmentation of the levels and activities of IL-6 in the pleural effusions. On fractionation of the pleural effusion by chromatography, one major peak of material with a mol. wt of 24 kD showed IL-6 activity. In contrast, no significant level of tumour necrosis factor-alpha or IL-1 beta was detectable in pleural effusions before or during local IL-2 therapy. These data suggest that IL-2 is an important regulatory factor of secondary IL-6 production.

Detection of a soluble antigen defined by monoclonal antibody 83D4 in serous effusions associated with breast carcinoma

Monoclonal antibody (MoAb) 83D4 was generated by immunization with cell suspensions obtained from sections of formol-fixed paraffin embedded human breast cancer. It recognized an antigen expressed in breast carcinomas but not in normal breast tissue. Pleural and ascitic fluids from 66 patients were studied by an 83D4 heterologous sandwich radioimmunoassay (SRIA) using solid-phase immobilized wheat germ agglutinin to detect the 83D4 soluble antigen. Using a cutoff level of 5 units/ml of 83D4 antigen, higher values were found in 22 of 27 breast cancer-associated effusions (mean = 10.72 +/- 6.80 units/ml). The 20 nonmalignant effusion fluids tested showed lower values (mean = 1.16 +/- 1.49 units/ml, P less than 0.001). The antigen was undetectable or present in low levels in effusions from patients with hematologic malignancies. When SRIA results were compared with conventional cytologic diagnosis in breast-cancer effusions, elevated levels of 83D4 soluble antigen were found in all patients (8 of 8) in whom malignant cells had been detected, in 4 of 8 patients with the diagnosis of "suspected malignancy," and in 10 of 11 patients with negative cytologic findings. Using an immunoglucosidase method on cell smears of various origins, MoAb 83D4 stained metastatic cells of breast and ovary carcinomas but did not reactive with mesothelial cells and other normal or malignant cell types. These results suggest that quantitation of the 83D4 soluble antigen may be used to improve the diagnosis of cancer in serous effusions.

Selected monoclonal antibodies can increase the accuracy of cytodiagnosis of neoplastic effusions of cryptic origin expanded in a short term culture

The use of a selected panel of monoclonal antibodies (MoAb) to tumor associated antigens (TAA) in immunocytochemical (IIC) tests has been shown, in a preliminary study, to be a powerful diagnostic tool for the identification of the primary solid tumor causing metastatic effusion. Despite this improvement in a minority of neoplastic fluids a number of different causes may still determine false negative (FN) immunocytochemical diagnoses. The aim of the present study was to confirm the diagnostic accuracy of this panel of MoAb. This was done by analyzing in IIC tests a larger number of effusions and by evaluating whether the expansion in short term culture of those fluids with an uncertain malignant morphology could provide an adequate cellular substrate for immunocytodiagnosis. The analysis of 314 effusions confirmed the results of the pilot study and demonstrated that the combination of short term culture and immunocytochemical assays can further increase the sensitivity of this novel diagnostic procedure from 84.3% to 95.3%.

[Carcinoembryonic antigen in pleural effusion. Adenocarcinoma versus mesothelioma]

One hundred and thirty six patients presenting pleural effusion and whose diagnosis was obtained by clinical, biochemical, bacteriological, cytological and histological methods have been studied and classified into seven groups: 20 transudates, 29 inflammatory, 25 tuberculosis, 25 non adenocarcinoid neoplasias, 24 adenocarcinomas, 10 mesotheliomas and 3 miscellaneous. Carcinoembryonic antigen was determined in all of them, evaluating as positives those values above 10 ng/ml, value which we consider discriminatory in our series and which agrees with the literature, finding positive values in 21 out of 24 adenocarcinomas and 3 out of 25 non adenocarcinomas. All benign pleural effusions and mesotheliomas had values lower than 10 ng/ml. The specificity to determine adenocarcinomas in neoplastic effusions was 91.48% and the sensibility was 87.5%. We consider that the CEA determination is useful to differentiate adenocarcinomas from other neoplasias and that a positive value rules out mesothelioma.

Identification of carcinoma cells in ascitic and pleural fluid. Comparison of four panepithelial antigens with carcinoembryonic antigen

The cell membrane antigens epithelial membrane antigen (EMA), epithelial glycoprotein 34, (egp34), BW-495 and tumor-associated antigen 72 (TAG-72) are present in most benign and malignant epithelial cells and can be demonstrated with the help of monoclonal antibodies. In a study on the identification of carcinoma cells in samples of ascitic and pleural fluid involving 170 patients, we compared the value of immunocytochemical labeling of these antigens with that of immunocytochemical demonstration of carcinoembryonic antigen (CEA). Antibodies to EMA and egp34 occasionally also reacted with reactively proliferating mesothelial cells in benign conditions and thus appear to be inappropriate for diagnostic use. Cells positive for BW-495, TAG-72 and CEA, however, have never been found in benign conditions; the specificity of these antigens thus permits their use in diagnosis. Antigen-expressing cells were found in 85% (BW-495), 62% (TAG-72) and 60% (CEA) of cytologically positive samples from carcinoma patients. Similarly, positive reactions for BW-495, TAG-72 and CEA were observed in, respectively, 36%, 29% and 34% of cytologically negative or suspicious samples. BW-495 thus appears to be a suitable marker for the demonstration of carcinoma cells in samples of pleural and ascitic fluid and to have a higher degree of sensitivity than does either TAG-72 or CEA.

Neopterin in tuberculous and neoplastic pleural fluids

Neopterin is derived from guanosine-triphosphate, produced by stimulated macrophages under the influence of gamma interferon of lymphocyte origin. It has been suggested as an excellent marker for activation of the monocyte/macrophage axis in some clinical situations. We evaluated its concentration in the pleural effusions of 25 individuals (10 tuberculous and 15 neoplastic) as well as in the blood of 22 of them (8 tuberculous and 14 neoplastic), comparing these levels with those of a control group in 99 normal individuals. The concentration of neopterin was determined by radioimmunologic assay. This showed a significant increase (p less than 0.001) of neopterin levels in the tuberculous pleural fluid, compared to the neoplastic group (42 +/- 23/17 +/- 9 nmol/L). In the blood, values were nearly identical to the pleural fluid (41.3 +/- 25/15.8 +/- 6.9 nmol/L), although with significant differences between them and in relation to the control group (p less than 0.001), which had a normal serum value (5.11 +/- 1.92 nmol/L). We emphasize the influence of the neopterin levels in the pleural fluid on the diagnosis of causes of pleurisy and its importance as a marker of immunologic cellular activity.

Identification of colony-stimulating factor activity in patients with malignant tumors associated with excessive leukocytosis

We have tried to demonstrate and identify colony-stimulating factor (CSF) activity in the plasma, pleural fluid, ascites or culture supernatant of tumor cells in 11 patients with malignant tumors associated with unexplained persistent leukocytosis. The specimens were treated with anti-granulocyte (G)-CSF or anti-granulocyte/macrophage (GM)-CSF monoclonal antibodies, then added to GM-progenitor (CFU-GM) cultures without exogenous CSFs. In all patients, untreated specimens generated CFU-GM-derived colonies, and colony formation was clearly inhibited by only one of the two antibodies, indicating the presence of either G-CSF or GM-CSF in the specimens. Furthermore, we measured the concentrations of G-CSF or GM-CSF in the specimens using an enzyme-linked immunosorbent assay, and confirmed the results by CFU-GM assay. Two patients were shown to have GM-CSF-producing tumors, while the other patients were G-CSF-producing. These assays are useful in identifying CSF activity in patients with CSF-producing tumors.

Cooperation between accessory cells and T lymphocytes in patients with tuberculous pleurisy

We studied interleukin 1 (IL-1) activity of pleural fluid macrophages and peripheral blood monocytes obtained from ten patients with tuberculous pleurisy and ten patients with malignant pleurisy, using purified protein derivative (PPD) as a stimulating agent. Tuberculous pleural fluid macrophages and peripheral blood monocytes tended to produce higher IL-1 activity than malignant pleural fluid macrophages and blood monocytes and showed significantly more IL-1 activity than healthy control monocytes. However, no significant difference in IL-1 activity was observed between tuberculous pleural macrophages and blood monocytes. With the cooperation of these accessory cells, pleural fluid T lymphocytes in patients with tuberculous pleurisy showed a significant level of interleukin 2 (IL-2) activity in the presence of PPD. Tuberculous pleural fluid macrophages promoted greater IL-2 production than blood monocytes from either tuberculous pleural fluid or blood T lymphocytes despite relative equivalence in measured IL-1 production. Combination of tuberculous pleural fluid macrophages and pleural fluid T lymphocytes was the most effective for increasing IL-2 activity when compared with other combinations. These results suggest that tuberculous pleural fluid macrophages and T lymphocytes may contribute to the immunopathogenesis of tuberculosis at a local site of disease.

Lambda light chain myeloma with pleural involvement

A case is reported of lambda light chain multiple myeloma complicated by a myelomatous pleural effusion. Pleural effusions are uncommon in multiple myeloma, and most are secondary to nonmalignant causes. The clinical characteristics, natural history and pathophysiology of myelomatous pleural effusions are reviewed.

Diagnostic significance of carcinoembryonic antigen in the differential diagnosis of malignant mesothelioma

The histologic and cytologic distinction of malignant mesothelioma from carcinomas metastatic to the pleura or peritoneum is often problematic. For this reason immunologic methods are being increasingly used as diagnostic adjuncts. This review summarizes 40 studies on the expression of carcinoembryonic antigen in mesotheliomas and in lung and other carcinomas involving the pleura or peritoneum. Carcinoembryonic antigen was identified immunohistochemically in 11% of mesotheliomas and in 84% of carcinomas examined and immunocytochemically (in serous effusions) in 4% and 58%, respectively. In serum and in pleural or ascitic fluid, significantly elevated levels of carcinoembryonic antigen are commonly associated with (lung) carcinomas but rarely with mesotheliomas. Thus, together with identification of the antigen in serum, pleural fluid, or ascitic fluid, immunohistochemical and immunocytochemical techniques for detecting carcinoembryonic antigen provide a valuable aid for distinguishing malignant mesothelioma from metastatic carcinomas.

[Clinical evaluation of pleural effusion--carcinoembryonic antigen (CEA) and adenosine deaminase (ADA) activities in pleural fluids]

We reviewed 327 patients with pleural effusion who had been examined at our department for identification of its cause during the 14 years between 1974 and 1987, and studied the percentages of definitive diagnosis by examining the pleural fluids of patients with malignant tumor and tuberculosis. We also measured the levels of carcinoembryonic antigen (CEA) and adenosine deaminase (ADA) in the pleural fluids of these patients and evaluated their diagnostic usefulness. We further carried out a detailed clinical study of the factors affecting the CEA and ADA activities in the pleural fluids, which are considered to be particularly important in differential diagnosis of patients with pleural effusion. Of 327 patients with pleural effusion, malignancy-related pleurisy was observed in 166 patients (50.8%), and tuberculous pleurisy in 85 (26.0%). The rate of definitive diagnosis based on the examination of the pleural effusion in these patients indicated that 20-30% of them pose difficulty in clinical diagnosis. CEA was positive in 64.7% of patients with malignancy-related pleurisy, and ADA was positive in 97.7% of those with tuberculous pleurisy. These suggested their usefulness as supportive diagnostic methods of those diseases. In addition, CEA was elevated in patients with complications such as empyema, suggesting an effect of non-specific cross-reacting antigen (NCA). ADA showed high values in patients with conditions related to cell-mediated immunological responses as well as empyema and hemolysis. It suggested the release of ADA from blood cells due to hemolysis. These factors must be carefully evaluated in the interpretation of the CEA and ADA activities in pleural effusion.

Induction of killer cells from lymphocytes in pleural effusion of advanced lung cancer patients

We analyzed the phenotype and cytotoxic ability of pleural exudative lymphocytes (PLEL) which were obtained from 18 advanced lung cancer patients. Freshly isolated PLEL were mainly CD4(+) T cells and had weak natural killer, autologous tumor killing and lymphokine-activated killer activities. After cultivation of PLEL with interleukin-2, cytotoxicity of PLEL against autologous tumor cells was increased at 2 weeks, but it was remarkably reduced at 4 weeks. When PLEL were stimulated by mitomycin C-treated autologous tumor cells during culture, autologous tumor killing activity of PLEL was significantly enhanced even after 4 weeks of cultivation. Cold target inhibition analysis and binding inhibition assays using monoclonal antibodies indicated that autologous tumor stimulation could induce major histocompatibility complex class I restricted cytotoxic T lymphocytes specific for autologous tumor cells in some cases.

[Eosinophil colony stimulating activity induced by administration of interleukin-2 into the pleural cavity of patients with malignant pleurisy]

Systemic administration of interleukin-2 (IL-2) in patients with malignant diseases induces peripheral eosinophilia. In the present study, to clarify the mechanisms of eosinophilia induced by IL-2, we examined the changes in the number of eosinophils and in eosinophil colony stimulating activity (Eo-CSA) in the pleural fluid of six patients with malignant pleurisy caused by lung cancer or malignant mesothelioma, during and after intrapleural administration of IL-2. Results showed that intrapleural administration of IL-2 induced marked eosinophilia in the pleural fluid and mild eosinophilia in the peripheral blood, and that during IL-2 administration, marked Eo-CSA appeared in the pleural fluid before increase in the number of eosinophils. The Eo-CSA seemed to be a polypeptide or protein because it was trypsin-sensitive and had a molecular weight of 40-60 kDa.