摘要:

AbstractVarious forms of cellular injury, whether induced by immune effector cells, aberrant metabolic processes, chemotherapeutic drugs or temperature shifts, result in common morphological changes consisting of the formation and shedding of membrane vesicles from the injured cell surfaces. This dynamic cell surface membrane behavior appears to be dependent on the disruption of cytoplasmic microtubules. Concommitant with the altered cell surface morphology certain physiological and biochemical events have been found to be associated with cell injury. These include changes in membrane permeability, elevated oxygen consumption rates and nuclear DNA fragmentation. However, it remains to be experimentally established which of these biological changes defines a state of irreparable cell injury.The objective of the present review is to compare and evaluate the cell injury process induced by effector lymphocytes with that caused by low temperature. The latter mimics most, if not all, the currently known criteria of immune effector cell mediated injury of target tumor cells.

ISSN:0892-3973    

DOI:10.3109/08923978909005384

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractIn order to assess the effects of the fungal toxin wortmannin on the immune system, rats and mice were fed wortmannin-containing cultures ofFusarium oxysporumfor 1 or 2 weeks. Wortmannin caused significant decreases in thymic weight, thymic lymphocyte numbers, serum IgG and IgM levels, the primary humoral response to T-dependent and T-independent antigens and the proliferative response of spleen cells to pokeweed mitogen.In vitroadministration of wortmannin did not produce evidence of cytotoxicity to spleen or thymus cells. The data indicate that wortmannin inhibits immune function in rats and mice and suggest that metabolic modification of the toxin is necessary for toxicity.

ISSN:0892-3973    

DOI:10.3109/08923978909005385

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractCells of the immune system possess K+ion channels which have been implicated in various cellular functions including activation, differentiation and cytolytic function. To define the role of K+ion channels in the lytic function of lymphokine-activated killer (LAK) cells, we investigated the effects of K+channel blockers on their cytolytic activity. Results show that when LAK cell mediated cytolysis of AKIL-20 tumor cexis was carried out in the presence of: a) the K+channel blocker, 4-aminopyridine (4-AP); b) the monoamine, serotonin (5-hydroxytryptamine; 5-HT); c) the serotonin agonist, quipazine; d) or the Ca++dependent K+Channel blocker, quinidine, the cytolytic activity of the LAK cells was inhibited in a dose-dependent manner. Preincubation of LAK effector cells also inhibited lysis in a dose-dependent manner, whereas preincubation of the AKIL-20 tumor target cells produced no inhibitory effects. This study demonstrates that K+ion channels are involved in the LAK cell cytolytic process and that compounds, including neuroendocrine products, which modulate K+ion channel function are capable of modulating the lytic activity of these effector cells.

ISSN:0892-3973    

DOI:10.3109/08923978909005386

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractThe major histocompatibility complex (MHC) encodes cell surface and secreted products involved in immune regulation and function. We have measured Class I MHC expression on doxorubicin (DOX) sensitive (P388/S) and resistant (P388/R84 and R84A) murine tumor cells using a monoclonal antibody to H-2d molecules. The present report shows a correlation between increased Class I MHC (H-2d) expression and drug resistance in P388 cells. Exposure of P388 cells to H-2d antibody diminished H-2dexpression, whereas, treatment with murine recombinantγ-interferon increased H-2dexpression. Neither treatment significantly altered cellular DOX resistance or chemosensitivity. Thus, H-2dmolecules can be used to identify DOX resistant P388 tumor cells but are probably not involved functionally in drug resistance.

ISSN:0892-3973    

DOI:10.3109/08923978909005387

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractSpleen and thymus weight, delayed-type hypersensitivity (DTH) to sheep red blood cells (SRBC), contact hypersensitivity to picryl chloride, anti-sheep red blood cell hemagglutinin titers and plaque-forming cells (PFC), resistance against experimental toxoplasmosis as well as serum total and intestinal specific IgA were investigated in Swiss mice given sodium valproate (250 mg/kg/day) orally for 21 consecutive days. Sodium valproate (SV) did not exert marked effects as only DTH to SRBC and PFC numbers were found to be slightly altered. These results suggest that SV is unlikely to alter immune competence markedly.

ISSN:0892-3973    

DOI:10.3109/08923978909005388

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractLauryl sucrose has recently been shown to decrease the toxicity of amphotericin B (AmB), a widely used antifungal agent, probably through a modulation of its physical state. In this paper, we demonstrate using a lymphoproliferative assay, that lauryl sucrose and monosubstituted analogs in addition to their effects on AmB also possess significant immune enhancer properties. An anti-bell shape relationship was observed between stimulation of lymphoproliferation and chain length of ester's fatty acid, lauryl sucrose being the less active of the tested derivatives. These properties of sucrose esters are discussed in the specific context of antifungal therapy.

ISSN:0892-3973    

DOI:10.3109/08923978909005389

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractMice infected for 45 days with 120Schistosoma mansonicercariae and treated with levamisole (25 mg/kg subcutaneously) have more efficient acquired immunity when challenged with 240Schistosoma mansonicercariae the same day of treatment (97.7% # 87.7% in infected challenged controls). In praziquantel-treated mice (500 mg/kg for 2 days orally), the reduction in the percent resistance (45.5%) was accompanied by a significant diminution in the size of granuloma, delayed foot pad swelling and granuloma proportionate T-helper cells number. Levamisole when given two weeks post praziquantel treatment and with the challenge infection increased the percent resistance to 79.2%. The increase in percent resistance recorded in mice receiving both praziquantel and levamisole was accompanied by restoration of granuloma size, delayed foot pad swelling and granuloma proportionate T-helper cells number to infected challenged untreated control values. Results reveal-beside efficacy of levamisole as immunoregulant in schistosome immunity - a possible role for the granuloma as a T-cell mediated response in maintenance of immunity.

ISSN:0892-3973    

DOI:10.3109/08923978909005390

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractThe effect ofin vivoadministration of Isoprinosine (ISO) on, i) the proliferation of splenic lymphocytes in response to the T-cell mitogen, concanavalin-A (Con-A) and, ii) the natural killer (NK) cell cytotoxicity was studied following a full skin thickness burn injury in a rat model. Administration of ISO (100 mg/kg body wt/day) twice daily, resulted in significant augmentation of the proliferative responses of lymphocytes compared to non-treated burned animals, at 7 days post injury. However, it did not effect the lymphoproliferation at 14 days post injury, the time period at which a complete suppression of lymphocyte proliferation was observed in burned non-treated animals. Also, the proliferation of lymphocytes from normal nonburned animals was not affected by treatment with ISO. ISO treatment of the burned animals resulted in a significant increase in the NK cytotoxicity compared to non-treated burned animals. As with Con-A responses, ISO administered to control nonburned animals did not have any effect on NK cell cytotoxicity. Our studies thus indicate that ISO can be a potential immunomodulator of suppressed immune funtion following thermal injury, particularly in patients whose lymphocyte responses to T cell mitogen Con-A are not completely suppressed.

ISSN:0892-3973    

DOI:10.3109/08923978909005391

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractThe effects of imuthiol®(sodium ditiocarb, DTC) on the expression of cytotoxic responses (CTL) and natural killer (NK) activity were evaluated in aged and young euthymic mice, and innu/nuBALB/c mice. Imuthiol generated CTL and concomitantly reduced NK activity innu/numice, suggesting that the agent can generate T cells in athymic nude animals. Treatment for up to 4 months augmented spleen NK and CTL activities in young or aged euthymic mice, but the generation of CTL in old animals was increased by long-term treatments better than by a single injection. The capacity of imuthiol to activate specific and nonspecific cytotoxic functions in euthymic mice may contribute to enhancement of resistancein vivoagainst transformed cells after treatment with this agent.

ISSN:0892-3973    

DOI:10.3109/08923978909005392

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractWe studied the effect of pyridoxine deficiency state on the responses of human lymphocytes to certain mitogenic factors. Deoxypyridoxine (DB6), a potent pyridoxine antagonist, considerably inhibited Bromodeoxyuridine (BrdU) incorporation into the newly synthesized DNA of lymphocytes cultured with Phytohemagglutinin (PHA) and Concanavalin A (Con A) in separate sets of experiments. The addition of deoxypyridoxine simultaneously with or few hours prior to initiation of cell cultures did not significantly alter the inhibitory action of deoxypyridoxine. Titration studies of deoxypyridoxine showed the direct relation between the concentration of deoxypyridoxine and the degree of DNA synthesis inhibition with subsequent lymphocyte proliferation. The results obtained with monoclonal antibody (anti-BrdU) studies were further confirmed with tritiated thymidine incorporation (3H Thymidine) studies. Addition of pyridoxine concurrently with the addition of DB6or 8 hours later than initiation of lymphocyte incubation period was capable of effectively reversing the inhibition caused by its antagonist, the level of DNA synthesis reaching that of the control cultures where only PHA or Con A were present. Our results confirm part of previously reported findings concerning the involvement of vitamine B6in immune processes.

ISSN:0892-3973    

DOI:10.3109/08923978909005393

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor