An integrative approach to the proteolytic control of the cell-mediated cytotoxicity.

The possible role of intracellular proteases in the control of the cell-mediated cytotoxicity of NK or CTL type, as components of the sequential molecular events leading to the target cell lysis, is emphasized by an integrative structural and functional approach. Starting from the own cytochemical researches and based on recent data, the effector cell proteases are analysed concerning their cellular and ultrastructural compartmentalization and their involvement in the sequential stages of the cytotoxic cycle. Membranous, granular, lysosomal and cytosolic compartments of the proteolytic activity are differentially elicited to interfere in the stimulus-secretion pattern of the cytotoxic function.

The cytochemical reaction of alpha-naphthyl-acetate esterase (ANAE) in peripheral blood lymphocytes of human cancer.

Peripheral blood lymphocytes from neoplasic patients have been investigated by cytochemical analyses of alpha-naphthyl-acetate-esterase (ANAE), marker of both cellular types and differentiation, maturation stages in relation with immunobiologic background of cancer. Our studies employed 32 cancerous human patients and compared them to 13 healthy people used as controls. The cytoenzymatic analysis was performed on whole blood samples, mononuclear cell concentrates (PBL) and rosetted ET and E45 preparations.

Histochemical reactions of myocardial proteases during open heart surgery.

Histochemical analysis of some lysosomal and sarcoplasmic proteolytic enzymes was assayed in human myocardial biopsies taken from 26 cardiopathic patients subjected to open heart operations, under extracorporeal circulation and protection with cardioplegic solution and hypothermia. The investigated myocardial proteases were: cathepsin B, cysteine aminopeptidase, acid gelatinases, trypsin-like endopeptidase, chymotrypsin-like endopeptidase and neutral gelatinases. The effects of surgical interventions appreciated by comparing the myocardium fragments harvested before, and at various intervals after aorta clamping (6-90 minutes) revealed disorders in the activity and compartmentalization of all the investigated proteases, whose histochemical reactions increased between 10 and 20 minutes after aorta clamping and manifested a lowering tendency with sarcoplasmic diffusion and extracellular release at longer periods than 20 minutes.

Histochemical investigation of myocardial proteases in heart anoxia, under protection with cardioplegic solution and protease inhibitors.

We studied the histochemical behaviour of neutral non-lysosomal and acid lysosomal proteases of the myocardium in heart anoxia by aorta-clamping, using an experimental model alike to the open heart surgery conditions. After one hour of blood deprivation we found destabilization, conglomeration, diffusion and extracellular release of the histochemical reactions for neutral BANA-reactive proteases, cathepsin B, acid and neutral gelatinases in monkey, rat and mice myocardium, in connection with lytic ultrastructural lesions. Intracardiac perfusion with cardioplegic solution exerted a partial protective effect which is improved by adding Trasylol, a protease inhibitor.

A particular case of large granular lymphocytes lymphoma.

A patient with non-cutaneous lymphocytic lymphoma with leukaemic spread is reported. The large majority of the peripheral blood mononuclear cells formed rosettes with sheep erythrocytes (E), had receptors for the Fc portion of IgG (Fc gamma R) and displayed an unusual enzymatic profile. Part of these cells had also labile bound surface membrane IgG.