Antigen-coated latex particles as a model system for probing monocyte responses in leprosy.

To study responses to Mycobacterium leprae antigens, we developed an in vitro model system in which latex particles coated with M. leprae sonic extract (MLSON) antigen were presented to monocytes. Uptake and oxidative response as measured by superoxide production to these antigens were investigated. Phagocytosis of MLSON-coated particles was greater than that of control particles in monocytes from both leprosy patients and controls from leprosy-endemic areas; uptake of MLSON-coated particles was higher in monocytes from lepromatous leprosy patients than in cells from tuberculoid leprosy patients and controls. In both patients and controls, uptake of latex particles coated with leprosy antigens triggered very little reduction of nitroblue tetrazolium although the cells were capable of mounting a respiratory burst. Antigen-coated latex particles can therefore be used as a tool to investigate monocyte responses to M. leprae and individual recombinant antigens.

Specificity of lymphocytotoxic autoantibodies (LCAbs) found in the serum of leprosy patients: class I MHC antigens.

Lymphocytotoxic autoantibodies (LCAbs) of the IgM class have been identified in patients with borderline tuberculoid (BT) and borderline lepromatous (BL) leprosy with Type I reactions (I) as well as lepromatous leprosy (LL) patients with erythema nodosum leprosum reactions (ENL). The observation that lymphocytotoxic activity (LCA) was reduced in the presence of platelets led us to determine whether LCAbs had specificities for Class I Major Histocompatibility Complex (MHC) determinants. Absorption of LCA positive sera with platelets, classically used to deplete Class I specific lymphocytotoxic antibodies, reduced LCA towards autologous as well as allogeneic target cells. This was true for LCA positive sera from all patient classifications (group BT in the autologous system, p less than 0.01; in all other patient groups, p less than 0.001). Introducing B-2m to cytotoxicity assays only marginally reduced LCA when added at high concentrations (5 mg/ml). An anti-Class I MHC antiserum which blocked the lytic activity. The data indicate that LCAbs while absorbed by platelets, are not specific for the Class I MHC antigens. The autoantigen recognized by these autoantibodies therefore remains to be identified.

Serum lymphocytotoxic activity in leprosy.

Sera from 167 patients across the spectrum of leprosy and 46 endemic controls were screened for lymphocytotoxic activity (LCA). The Terasaki microdroplet lymphocytotoxicity assay was performed at 37 degrees C and 15 degrees C to test sera for LCA against a panel of lymphocytes from 50 donors which represented most known HLA-ABC antigens. Raised complement-dependent LCA at 15 degrees C was seen in leprosy patients with histories of erythema nodosum leprosum (ENL) or reversal/Type I (I) reactions. Eighty-six per cent of lepromatous (LL) patients with a history of ENL (n = 21, P less than 0.001), 83% of borderline lepromatous (BL) and 88% of borderline tuberculoid patients (BT) with a history of Type I reactions (n = 12, P less than 0.01 and n = 24, P less than 0.001 respectively) had LCA compared to 39% of endemic controls (n = 46). LCA was attributed to IgM on the basis of reduced activity when serum was treated with both dithiothreitol or absorbed with antiserum for IgM. Removal of immune complexes and rheumatoid factor did not influence LCA. LCA-positive sera reacted similarly with allogeneic lymphocytes from either healthy donors or leprosy patients. Moreover LCA-positive sera reacted with autologous lymphocytes. Specificities for HLA-ABC antigens were not identified. The potential role of these autoantibodies, manifested in leprosy patients with hypersensitivity reactions remains speculative.

[Surgical treatment of chronic constipation]. / Khirurgicheskoe lechenie khronicheskogo zapora.

The results of clinical use of periarterial neurectomy of the superior mesenteric artery, the Bauhin's valve plasty according to Vitebsky, and their combination with different variants of colonic resection, subtotal and total colectomy with creation of ileosigmoid and ileorectal anastomosis in 64 patients are presented. The best functional results were noted after subtotal colectomy with the ileosigmoid anastomosis formation.