Antilymphocyte antibody purified by immunoabsorption and elution.

A comparison has been made of several techniques for the preparation from antilymphocyte serum of pure antilymphocyte antibody by absorption on, and elution from mouse thymocytes. The best yield was obtained by a batch method using cells fixed in 0·1% formaldehyde as immunoabsorbent followed by elution with 0·12 M citrate buffer at pH 3·0. The antilymphocyte activity of eluates was studied by determination of membrane immunofluorescence titres and by the neutralization of the local renal xenogeneic graft-versus-host reaction.

Incidence of autoantibodies in cancer patients.

A review of the incidence of autoantibodies to normal tissue constituents in 250 patients with malignant disease has shown positive tests in 15% compared with 24% in patients with general non-neoplastic disorders and 8% in normal blood donors. In patients with lymphoma or leukaemia, the incidence of anti-smooth muscle antibodies was 15% compared with 4% in the control population; there was no increase in the incidence of anti-smooth muscle antibodies in patients with other malignant conditions. The incidence of anti-smooth muscle antibody in 4000 sera submitted for the investigation of possible autoimmune disorders is also reviewed.

Immune response to a syngeneic rat tumour: evolution of serum cytotoxicity and blockade.

The development of serum factors by Wistar rats during the growth of a syngeneic squamous cell carcinoma has been investigated to clarify the nature of the local lymphocyte anergy reported previously in this system. Sera from tumour bearing animals were tested for cytotoxicity against tumour cells by in vitro microassay, and their ability to inhibit cell mediated cytotoxicity was also studied. Serum cytotoxicity was first detected after 2 weeks of tumour growth, reaching a peak at 4 weeks and then declining.

Lymphocyte anergy in patients with carcinoma.

All of 10 patients with colonic carcinoma and 5 with malignant melanoma of skin showed no sign of immunoreactivity against the cultured tumour cells by the lymphocyte populations residing within the tumours. More than half of these patients did show cytotoxic reactivity by their blood lymphocytes. Possible cytotoxic reactivity by the regional lymph node lymphocytes was also investigated in 57 tumour cases (44 colonic, 13 melanoma, and including 12 of the 15 examined for intrinsic lymphocyte activity).

Immune response to a syngeneic rat tumour: development of regional node lymphocyte anergy.

The development of cellular immunity to a syngeneic squamous cell carcinoma in Wistar rats was studied by in vitro microcytotoxicity assay. Reactivity of lymphocytes from lymph nodes, spleen and blood was tested throughout the period of tumour growth. Maximum lymphocyte cytotoxicity against the tumour was observed at 2 weeks in regional lymph nodes, 4 weeks in intermediate nodes, spleen and blood, and 6 weeks in distant nodes; the intensity of these cytotoxic responses subsequently declined.

Ultrastructural localization of antilymphocyte globulin on viable lymphocytes by immunoperoxidase tracing.

Immunoperoxidase tracing of the interaction of antilymphocyte globulin (ALG) with intact lymphocytes of mouse thymus and spleen showed surface membrane localization by light and electron microscopy. Ultrastructural studies of sections of lymphocytes and, by `stereoscanning', of whole cells, revealed a generally regular pattern of interrupted surface binding of the labelled antibody. The findings suggest that the antigenic determinants reacting with the ALG are uniformly distributed on the plasma membrane at some 50-nm intervals.

Gastric parietal cell autoantigen. Physical, chemical and biological properties.

The properties of the gastric parietal cell autoantigen have been further investigated using mucosal subcellular fractions and gastric sections. Sucrose density layer ultracentrifugation of a microsomal preparation from bovine abomasum fundus (gastric) mucosa allowed the separation of an antigenic smooth membrane fraction, providing further evidence that the antigen is associated with smooth cytoplasmic membranes. Both hydrophobic and polar bonds appear to be concerned with maintenance of antigenic structure.

Immunological reactivity in patients with carcinoma of colon.

Sixty cases of colonic carcinoma have been investigated for antitumour immunoreactivity. The tests employed were blood lymphocyte reactivity and complement-dependent serum cytotoxicity against cultured tumour cells, and immunofluorescence for membrane staining of viable tumour cells and cytoplasmic staining of dried tumour cells in films. Nineteen cases were positive by one or more tests and the most frequent positive response, lymphocytotoxicity, was detected in 8 of the 24 cases tested in this way.

Specific immune response in human skin carcinoma.

Eight out of nine patients with squamous cell carcinoma of skin have shown immunological reactivity against their own tumour cells by one or more tests with their sera or peripheral blood lymphocytes. The tests included membrane and cytoplasmic immunofluorescence, and, with cultured tumour, complement-dependent serum cytotoxicity and lymphocyte attack. One case examined in depth had an unusually conspicuous lymphocyte and plasma cell reaction on histological examination, and was positive by all four tests; a time-lapse cinephoto-micrographic record over seven days was obtained of the attack on the carcinoma cells in culture by the patient's lymphocytes.

Simple separation of lymphoid cells from granulocytic series in rat bone marrow.

Lymphocyte-rich fractions were separated from rat bone marrow by means of a glass wool column. The large marrow cells were removed by a filter effect and the mature granulocytes by their adhesion to the glass wool surface. The majority of erythrocytes and their precursors were not removed.