Leukocyte adherence inhibition and specific immunoreactivity in malignant melanoma

Abstract

The leukocyte adherence inhibition (LAI) test has been used to assess specific anti-tumour immunoreactivity in 80 patients with malignant melanoma, 21 of whom had apparently been successfully treated by surgery, and 44 control subjects. Reaction with melanoma extracts in vitro enabled the activity of blood leukocytes to be detected by inhibition of their adherence to glass, while serum was tested for factors which modified this inhibition. Of the patients with tumours (ranging from primary melanoma in situ to advanced disseminated disease), 22/24 had active leukocytes and 50/58 has serum blocking factor; two of the sera, from patients with regressing tumours were unblocking. After surgery with no clinical recurrence, leukocytes continued to be active except when tested several years after operation. Blocking factor rapidly disappeared in 16/20 patients tested, and in several patients examined serially the serum became unblocking. In three cases, persistence of serum blocking was followed by clinical diagnosis of metastases. Leukocyte activity was nerver detected in control subjects (0/10), many of whom had other kinds of tumours or skin lesions. Blocking activity in serum was found in only 3/38 controls with no history of melanoma (1 had a fibrosing cellular blue naevus and 2 had liver disease). Thus the LAI test correlated well with clinical and pathological findings, and shows great promise for the reliable, rapid and specific immunodiagnosis of malignant melanoma.

Anti-tumour immunity in malignant melanoma assay by tube leucocyte adherence inhibition

“…Anti-tumour immunity to the malignant melanoma antigen as measured by LAI was depressed by surgery and chemotherapy. In contrast to the report of Halliday et al (1975), melanoma patients with a large tumour load exhibited diminished or no LAI; moreover, in "tumour-free " patients LAI to malignant melanoma extract was not detectable 6-8 months after excision of the tumour.…”

“…In agreement with the study of Halliday et al (1975), the tube LAI assay for malignant melanoma appears to be immunologically specific and reproducible. Peripheral blood leucocytes of 20 out of 25 patients (80%) with active malignant melanoma responded to an extract of malignant melanoma with significant leucocyte adherence inhibition, whereas 4*5 00 of control subjects showed a response.…”

“…The results of the present study indicate that the anti-tumour immune response of the malignant melanoma patient was dependent on the extent of the cancer, whereas Halliday et al (1975) have not reported any variation in LAI with extent of disease. Patients with cancer confined to the primary site had strong responses and 11 out of 13 patients had a positive NAI.…”

“…Holan et al (1974) and Grosser and Thomson (1975) reported that the addition of serum directly in the tube LAI assay either had a non-specific effect or no effect at all. By contrast, Halliday et al (1975) and Maluish and Halliday (1974) have reported that serum from early and late tumour-bearers " blocks " the assay, and serum from " cured " patients is frequently unblocking". We have found that, by pre-incubation of normal leucocytes with serum from reactive patients with melanoma or breast cancer, and washing the cells before plating them in the tube LAI assay, immunologically specific " arming " can be detected.…”

“…Recently Halliday et al (1975) reported the results of the LAI assay in 75 patients with malignant melanoma. We studied LAI in 33 patients with malignant melanoma by the LAI assay in test tubes (Tube LAI assay), an assay that appears to differ only methodologically.…”