Characterization of two human small cell lung carcinoma-reactive monoclonal antibodies generated by a novel immunization approach.

Two human small cell lung carcinoma cell lines, NCI-H69 and NCI-H128, were used as alternating sources of immunogen to generate monoclonal antibodies to small cell lung carcinoma-associated antigens. BALB/c mice were sensitized with seven injections of live tumor cells, four with NCI-H69 cells and three with NCI-H128 cells. Somatic cell hybridization was performed by fusion of the immune murine splenocytes using syngeneic myeloma cells from the SP2/0 Ag14 cell line. Hybridoma colonies were screened against small cell lung carcinoma cells and normal lung fibroblasts with an enzyme-linked immunosorbent assay. Compared to animals immunized with only NCI-H69 or NCI-H128 cells, alternate immunization resulted in the generation of a significantly higher number of hybridomas that reacted selectively with both tumor cell lines. Monoclonal antibodies from two reactive hybrid clones generated by alternate immunization, SCLC 2051 and SCLC 5023, were uniformly negative to normal human tissues including lung, kidney, liver, spleen, breast, thyroid, brain, small intestine, and colon. While both monoclonal antibodies were nonreactive to paraffin-embedded, formalin-fixed, nonmalignant lung biopsies, the monoclonal antibody SCLC 5023 reacted with tumor cell infiltrates in biopsies from small cell lung carcinoma patients (14 of 14 cases positive), using the immunoperoxidase technique. This monoclonal reagent also reacted with other lung tumor cell types, including atypical carcinoid (5 of 5 positive), epidermoid (4 of 6 positive), undifferentiated and bronchoalveolar (3 of 4 cases each positive) carcinomas. By contrast, monoclonal antibody SCLC 2051 apparently identified an antigen expressed preferentially on small cell lung carcinoma cells (12 of 14 positive) and only rarely reacted with other lung tumor cell types (2 of 34 positive). Both monoclonal antibodies were negative to colon carcinoma, epidermoid carcinoma of the floor of the mouth, breast adenocarcinoma, and B- and T-cell leukemia and lymphoma cells, as determined by the enzyme-linked immunosorbent assay, indirect immunofluorescence, and immunoperoxidase techniques. These observations suggest that SCLC 2051 and SCLC 5023 may be of value in identifying tumor-associated antigens expressed in small cell and other lung carcinomas. In addition, the generation of antibody-producing cells towards common tumor-associated antigens may be enhanced by immunization with multiple tumor cell lines of the same histological type.

Salivary and bronchial immunoglobulins in patients with respiratory tract carcinoma.

Patients with carcinoma of the respiratory tract have been demonstrated to have elevated levels of immunoglobulins in the secretions bathing these areas. The clinical significance of this finding has remained unclear. In the present study, IgA and IgG levels were correlated with 5 year survival statistics in 53 patients with oral squamous cell carcinoma. Our findings indicate that there is no correlation between local IgA or IgG level and length of patient survival.

Lambert-Eaton myasthenic syndrome.

The Lambert-Eaton Myasthenic Syndrome (LEMS) is characterised by proximal muscle weakness initially affecting gait, autonomic symptoms (dry mouth, constipation, erectile failure), augmentation of strength during initial voluntary activation, and depressed tendon reflexes with post-tetanic potentiation. The disorder is paraneoplastic (small cell lung cancer) in about 60p. cent (P-LEMS); no cancer is associated in the remainder (NP-LEMS). LEMS affects all races. NP-LEMS can occur in childhood as well as adult life; P-LEMS is unusual at<30 Years. The weakness results from a reduction in the quantal release of acetylcholine from motor nerve terminals, caused by autoantibodies to P/Q-type voltage-gated calcium channels (VGCCs) that are provoked by tumour VGCCs in P-LEMS; the stimulus in NP-LEMS is not known. These antibodies may be implicated in the rarely associated cerebellar degeneration. The diagnosis can be confirmed by detecting the specific antibody in a radioimmunoprecipitation assay, and by finding a reduced compound muscle action potential amplitude that increases by>100p. cent following maximum voluntary activation. Most patients benefit from 3,4-diaminopyridine; pyridostigmine is less effective. Specific tumour therapy in P-LEMS will often ameliorate the neurological disorder. In those with severe weakness, IVIg or plasmapheresis confers short-term benefits. Prednisone alone or combined with azathioprine or cyclosporin can achieve long-term control of the disorder.

Antiglycine receptor antibody and encephalomyelitis with rigidity and myoclonus (PERM) related to small cell lung cancer.

A 39-year-old man (a lifetime non-smoker) presented with a locked left jaw and leg myoclonus. Clinical and electromyographic findings were in keeping with progressive encephalomyelitis with rigidity and myoclonus (PERM) syndrome. A thoracic CT scan demonstrated a 19 mm right hilar nodule, which was proven to be small cell lung cancer on bronchoscopic biopsy. Serological evaluation of the patient's plasma revealed antibodies against glycine receptors (serology negative for anti-GAD, anti-Yo, anti-Hu, anti-Ri, antiamphiphysin, anti-Ma2/Ta, anti-CRMP5 and anti-NMDA receptor). After his cancer was treated with chemotherapy and intravenous immunoglobulins (IVIg), neurological symptoms resolved but returned several months later without any evidence of cancer recurrence. Symptoms were refractory to corticosteroids and IVIg therapy. Rituximab was then initiated, which led to a dramatic and sustained resolution of symptoms. To our knowledge, this is the first case of PERM related to antiglycine receptor antibodies from paraneoplastic syndrome, which resolved with rituximab.

Alveolar macrophage function is altered in patients with lung cancer.

The alveolar macrophage (AM) is believed to be of central importance in the immune response against infection and tumour. We examined patients with lung cancer in order to evaluate the immuno-stimulatory potential of AM in lung cancer. Bronchoalveolar lavage fluid samples were obtained from patients with adenocarcinoma, squamous cell carcinoma, large cell undifferentiated lung carcinoma, small cell carcinoma and control subjects. AM were isolated and phagocytic function, flow cytometry and cytokine analysis were assessed. AM from patients with small and squamous cell carcinoma had impaired uptake in vitro of 40 nm fluorescent polystyrene beads. AM from patients with small, squamous and large cell undifferentiated carcinoma showed impaired uptake of 1000 nm fluorescent polystyrene beads. Secreted levels of TNF-alpha and IL-1 from AM of patients with small, squamous, and large cell undifferentiated carcinoma were decreased compared to controls. Secreted AM IL-6 levels were decreased in small and large cell undifferentiated carcinoma. AM from adenocarcinoma patients showed similar levels of IL-10, IL-6, IL-1 and TNF-alpha compared to controls. Phenotypic analysis demonstrated that patients with small cell carcinoma were the only group that showed a decrease in MHC class II surface expression. Surface expression of ICAM-1 and CD83 was decreased on AM from patients with large, squamous and small cell carcinoma compared to controls but not adenocarcinoma. Mannose receptor levels were only decreased on AM from patients with squamous and small cell carcinoma but not adenocarcinoma and large cell undifferentiated carcinoma. We conclude that there are type-specific alterations in uptake ability, cytokine secretion and phenotype of AM from lung cancer patients, which may result in an inability to stimulate anti-tumour immunity. The observed differences between lung cancer subgroups may explain previously reported inconsistencies in descriptions of AM characteristics in lung cancer.

Quantitative investigations of cell-bubble interactions using a foam fractionation technique.

Previous work by the authors and others has shown that suspended animal cell damage in bioreactors is caused by cell-bubble interactions, regardless whether the bubbles are from bubble entrainment or direct gas sparging. As approach to measure the adsorptivity of animal cells to bubbles, a modified batch foam fractionation technique has been developed in this work and proven to be applicable. By using this technique, the number of cells absorbed per unit bubble surface area and the adsorption coefficients have been measured to quantify hybridoma cell-bubble interactions, and the preventive effects of serum and Pluronic F68 on these interactions. It was demonstrated quantitatively that the hybridoma cells adhere to bubbles spontaneously and significant numbers exist in the foam, and that both the serum and Pluronic F68 provide strong prevention to these cell-bubble interactions. The results obtained provide criteria for bioreactor operation and medium formulation to prevent cell-bubble interactions and cell damage in the culture processes.