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At least 19 recordsLinked to original sources
PubMed1990

Cytokine modulation of adhesion molecules in the regulation of immunologic cytotoxicity of epidermal targets.

Immunologic cytotoxicity is an important endpoint of the immune response to tumors, viral infected cells, grafted tissues, and exogenous microorganisms, and is also an important mechanism of disease, especially in autoimmunity. There are multiple mechanisms of immunologic cytotoxicity, but each has three major stages: leukocyte/target attachment, specific recognition, and target lysis following effector activation. Adhesion molecules present on leukocytes and potential targets appear to be involved in all three stages of cytotoxicity. A major factor in all types of cellular cytotoxicity is the interaction of LFA-1 on leukocytes and CAM-1 on targets. Modulation of ICAM-1 levels on target by the cytokines TFN-g, IL-1, and TNF-a is a major point of control of the susceptibility of targets to cytotoxicity by many different cytotoxic mechanisms. It also appears that modulation of the avidity of LFA/ICAM-1 binding is another important control point in modulating immunologic cytotoxicity. Cytokines also have important effects on immunologic cytotoxicity in ways other than adhesion molecule induction: effector priming to better respond to specific recognition signals, effector mobilization into tissue, and expansion of cytotoxic effector populations. ICAM-1 on the surface of epidermal keratinocytes and melanocytes is likely to greatly influence cytotoxic damage of these cells in diseases as photosensitive lupus erythematosus, lichen planus, erythema multiforme, and vitiligo. It has been found that the epidermal staining pattern for ICAM-1 in each of these diseases in distinctive and different in each disease. It is proposed that disease-specific induction of ICAM-1 by factors such as UVR and herpes-virus is an important determinant in triggering these skin diseases and in determining the pattern of disease.

Cell Adhesion Molecules↗
PubMed1980

Immunologic cytotoxicity against autologous human lymphocytes transformed or infected by Epstein-Bar virus: role of antibody-dependent cellular cytotoxicity in health individuals.

Immunologic cytotoxicity against lymphocytes transformed or infected by Epstein-Barr virus (EBV) was mainly studied in an autologous in vitro system by 51Cr release assay and EBV-determined nuclear antigen (EBNA)-specific trypan blue exclusion method. When the cells of newly established EBV-transformed or spontaneously transformed lines were incubated with unfractionated autologous healthy donor lymphocytes or T-cell-depleted lymphocytes in the presence of EBV-positive autologous or allogeneic serum, the transformed cells were killed with high frequency. Exposure to lymphocytes alone or to EBV-positive serum alone was not effective. The cytotoxic reaction was directed against cells positive for EBV-induced membrane antigens (MA) but not against MA-negative transformed cells. A very small fraction (1 of 200) of healthy donor lymp]hocytes exposed to EBV converted into EBNA-positive and MA-positive cells, and these were also killed by the remaining autologous lymphocytes in the presence of EBV-positive serum. These results indicated that the present cytotoxic reaction represents antibody-dependent cellular cytotoxicity (ADCC), and this particular mechanism probably plays an important role in the immunologic surveillance in the protection against EBV-induced oncogenesis in seropositive individuals. Such ADCC, however, does not seem to function effectively in patients with systemic lupus erythematosus.

Antibodies, Viral↗
PubMed1976

Inhibition by lymphoid cellular factors of the immunological cytotoxicity against a syngeneic tumour.

Lymphoid cells of C57BL mice bearing a syngeneic sarcoma are cytotoxic against the same tumour cells in vitro at two different periods of the growth of the tumour separated by a "mute period". Without additional antigenic stimulation the lymphoid cells from the "mute period" can be made cytotoxic by preincubation in vitro and elimination of adherent cells by a passage through a glass bead column. Either of these treatments alone is inefficient. The cytotoxicity revealed in this way is due to cells with different properties than those that are directly cytotoxic during the 4th week of the tumour growth. The significance of these results is discussed. It is suggested that some other cells have to be eliminated because they compete with or inhibit the activity of the "mute period" lymphoid cells made cytotoxic by preincubation.

Animals↗
PubMed1994

Non-immunologically-mediated cytotoxicity of Lactobacillus casei and its derivative peptidoglycan against tumor cell lines.

Lactobacillus casei, which shows antitumoral activity mediated by the stimulation of cellular defence mechanisms, and its peptidoglycan were tested for their ability to inhibit in vitro the viability of various murine (Yac-1, P815, Ehrlich ascites tumor, mammary carcinoma) and human (K562, KB) tumor cell lines through primary cytotoxic activity. Treatment of these tumor line with L. casei or its peptidoglycan at different doses and for different times demonstrated a decrease in viability by 25-30%. This cytotoxic activity was revealed by 51Cr release, succinate dehydrogenase (SDH) activity, ATP assays and morphological alterations in the treated tumor cells. Immunoenzymatic assays (ELISA) showed a precise ratio of binding between Ehrlich ascites or YAC-1 cell membranes and peptidoglycan. This binding is discussed with regard to the structure of the peptidoglycan molecule. The results suggest that L. casei and its derivative peptidoglycan have both a stimulating activity in normal cells and an inhibiting activity in tumor cells, as has been found for other immunomodulatory complexes.

Adenosine Triphosphate↗
PubMed1986

Immunologically mediated cytotoxicity against human eye muscle cells in Graves' ophthalmopathy.

The possible roles of antibody-mediated complement-dependent cytotoxicity (AMC), antibody-dependent killer (K) cell-mediated cytotoxicity (ADCC), and spontaneous, natural killer (NK) cell-mediated cytotoxicity (NKC) against human eye muscle cells in the pathogenesis of Graves' ophthalmopathy were investigated, using as targets human eye muscle cells, by 51Cr release assays. AMC was not demonstrated in serum from any patient or normal subject. In ADCC assays, eye muscle cell lysis was significantly increased in serum from patients with Graves' ophthalmopathy compared to those with Graves' hyperthyroidism without eye disease and normal subjects. ADCC tests were positive (percent specific lysis greater than the upper limit of normal) in 5 of 13 patients with Graves' ophthalmopathy using serum diluted 1:48 and in 4 of 10 patients using serum diluted 1:6. There was no correlation between the extent of lysis of human eye muscle and that of human (abdominal) skeletal muscle and no difference between patients with Graves' ophthalmopathy and normal subjects in assays in which abdominal muscle cell targets were used. The degree of killing in ADCC tests was independent of the source of K cells, being similar in assays using effector cells from the patient, another patient, or a normal subject. ADCC activity was partially absorbed by thyroid, orbital connective tissue and eye muscle membranes, and eye muscle cells, but not by liver membranes of thyroglobulin. Four of 8 human monoclonal antibodies reactive with eye muscle membrane antigens were cytotoxic in ADCC assays. A noncytotoxic monoclonal antibody blocked the ADCC effect of serum from a patient with Graves' ophthalmopathy, while a cytotoxic monoclonal antibody enhanced killing. NKC against eye muscle cell targets was depressed in cells from hyperthyroid and euthyroid patients with Graves' ophthalmopathy compared to that in normal subjects. Demonstration of ADCC against human eye muscle cells in some patients with Graves' ophthalmopathy suggests that this may be a mechanism for the eye muscle cell damage characteristic of this disorder. Inability to demonstrate cytotoxicity in a greater proportion of patients may reflect the lack of specific criteria to identify patients with active eye muscle inflammation and the unsuitability of currently available tests for the detection of serum antibodies against eye muscle membrane antigens. The mechanism for depressed NK cell-mediated cytotoxicity against eye muscle cells in this disorder is not known.

Adult↗
PubMed1980

Multiple myeloma: an immunologic profile. Cytotoxic and suppressive effects of the EA rosette-forming cell.

Lymphoid cells bearing receptors for human IgG anti-Rh antibody but not otherwise identifiable as T or B cells were isolated from the peripheral blood of human multiple myeloma patients. These cells do not demonstrate surface immunoglobulin, do not secrete immunoglobulin in culture after stimulation with pokeweed mitogen, and do not possess receptors for the third component of complement. They do not form rosettes with sheep erythrocytes, and do not respond to known T cell mitogens. These cells are not phagocytic and do not possess demonstrable nonspecific esterase. Thus, they must be considered at present, members of the "third population" lymphoid cells. These cells are active in the cytotoxic response by myeloma peripheral blood lymphocytes to myeloma plasma cells accounting for approximately 60% of such activity. They are also responsible for part of the suppression of pokeweed mitogen-stimulated immunoglobulin production, and at equivalent suppressor to target cell ratios are more active than immunoregulatory monocytes. Thus, these cells play an important, not previously widely appreciated role in the pathophysiology of the human myeloma patient.

Antibodies↗
PubMed1993

Antitumor activity and tumor necrosis factor production of Phytolacca acinosa polysaccharides I in mice.

The antitumor activities of Phytolacca acinosa polysaccharides I (PAP-I) and its effects on the induction of tumor necrosis factor (TNF) and immunological cytotoxicity of peritoneal macrophages were studied. PAP-I was given ip 5-20 mg.kg-1.d-1 x 7 d to ICR mice as priming agent with subsequent lipopolysaccharides (10 micrograms/mouse) iv for TNF production. TNF activity was measured by crystal violet staining assay using L929 cells. PAP-I showed priming activity for TNF production with hepto-splenic hyperplasia in a dose-dependent manner. The peritoneal macrophages treated with PAP-I 10 and 20 mg.kg-1 showed 67 and 74%, respectively, cytotoxicity (the control 34% cytotoxicity) against Meth A cells at effector:target = 40:1. PAP-I 10 and 20 mg.kg-1 prolonged the survival time of mice bearing ascites Meth A tumor from 21 +/- 4 to 32 +/- 10 and 38 +/- 8 d and inhibited the solid Meth A tumor growth with inhibition rate of 28.5 and 55.7%, respectively. These results suggested that the antitumor activities of PAP-I were based on the activation of macrophages and induction of TNF.

Animals↗
PubMed1989

Genetic, immunological, and cytotoxic comparisons of Legionella proteolytic activities.

Several strains of Legionella pneumophila and other species of Legionella with proteolytic activities were compared by assays, including Southern hybridizations and Western immunoblots, to determine their proteolytic, hemolytic, and cytotoxic activities. Only proteases from strains of L. pneumophila were both hemolytic and cytotoxic, and proteolytic activities extracted from other species of Legionella possessed only hemolytic activity. A 4.0-kilobase DNA sequence encoding the 38-kilodalton metalloprotease from L. pneumophila Philadelphia 1 that we showed previously was responsible for the observed hemolytic and cytotoxic phenotypes (F. D. Quinn and L. S. Tompkins, Mol. Microbiol., 3:797-805, 1989) was used in Southern hybridizations to probe chromosomal DNA from several strains of L. pneumophila and other Legionella species. The probe hybridized to the chromosomal DNA of all serogroups of L. pneumophila but not to any strains of L. dumoffii, L. micdadei, L. feeleii, or L. jordanis that we examined. Additionally, Western immunoblots done with rabbit antisera made to the cloned L. pneumophila protease demonstrated cross-reactions among 38-kilodalton proteins from strains of L. pneumophila, but no reactions were observed with proteins from other species of Legionella. Similarly, the cloned protease from L. pneumophila reacted with convalescent-phase sera from patients infected with L. pneumophila, but not with antisera isolated from patients infected with other Legionella species. Thus, despite some similarities among the proteolytic activities of members of the genus Legionella, including proteolytic and hemolytic phenotypes, metal requirements for zinc or iron, sensitivity to EDTA, and temperature and pH optima, we documented distinct genetic, immunological, and cytotoxicity differences among the proteolytic activities produced by Legionella species.

Blotting, Southern↗
PubMed1977

Renal donor pretreatment with cytotoxic agents: immunologically ineffective and damaging to the graft.

Simultaneous double renal allografts were performed in 32 dogs to evaluate the effect of pretreatment of the donor kidney with either Medrol, cytoxan, and methotrexate or medrol and procarbazine. There was no prolongation of survival of treated allografts. Immunosuppressive therapy for the transplanted animal unmasked a pretreatment injury of the pretreated kidney. Treatment of an autograft kidney in an intermediate host produced a cytotoxic tubular lesion in the kidney and also appeared to protect the kidney from the double ischemic insult incurred during the transplantation procedure. Pretreatment of dog donors of renal allografts with cytotoxic agents thereby offers no immunologic advantage for graft survival and produces a cytotoxic tubular lesion that is detrimental to kidney survival when ischemic and immunologic injury is minimal.

Animals↗
PubMed1980

Antibody-mediated complement-dependent cytotoxicity in immunologically induced experimental colon disease.

Rabbits immunized with a saline extract of intestinal tissue in complete Freund's adjuvant produce antibody which mediates complement-dependent cytotoxicity for colon epithelial cells in vitro. The presence of this antibody did not correlate with histologic alterations of the colon in the immunized rabbits. This suggests that antibody-mediated complement-dependent cytotoxicity may not be a factor in the pathogenesis of experimentally induced immunologically mediated colon disease.

Animals↗
PubMed1982

Immunoselection of tumor variants resistant to antibody-mediated cytotoxicity. Their immunologic and metastatic characterization.

The immunological characteristics of two series of metastatic variants of restricted genetic origin were related to their lung-colony-forming potential. A series of metastatic variants was isolated from a tumor-cell population in which heterogeneity appeared following short-term in vivo passage, while a second series of variants were immunoselected in vitro for resistance to antibody-complement-mediated cell lysis. In the case of the first series, the sensitivity of the individual variants to cell-mediated and antibody-complement-mediated cytotoxicity appeared to be partly determined by the number and rate of loss of antibody-binding sites on the cell surface. These characteristics also correlated with the efficiency of experimental metastasis in the animal. We compared the results reported herein with our previous studies of nonimmune parameters for this series of metastatic variants, and we conclude that immunological differences can be important to the efficiency of lung-colony formation. However, in the case of the second series of variants, despite selection in vitro for resistance to antibody-complement-mediated cell lysis, the behavior of these variants in the lung colony assay could not be predicted by the immunologic parameters examined.

Animals↗
PubMed1991

Immunologically mediated cytotoxicity against human eye muscle and thyroid cells in euthyroid and thyrotoxic Graves' ophthalmopathy.

We have studied the role of eye muscle and thyroid autoimmunity in patients with Graves' hyperthyroidism with or without ophthalmopathy in an area of relatively low iodine intake. Antibody dependent cell mediated cytotoxicity (ADCC) and complement mediated antibody dependent cytotoxicity (CMAC) against thyroid and eye muscle cells, and levels of antibodies against TSH receptor antigen and the thyroid microsomal antigen (thyroid peroxidase) were determined in three groups of patients: (1) thyrotoxic with exophthalmos (TX, n = 28), (2) thyrotoxic without ophthalmopathy (GR, n = 10), and (3) euthyroid ophthalmopathy (EU, n = 12). The thyroid glandular mass of the EU group was significantly less (P less than 0.01) compared with TX or GR. Mean (+/- SD) TSH receptor antibody (TRAb) level was 27 +/- 14% in EU which was significantly lower compared with TX (52.4 +/- 20%) and GR (59 +/- 18%). The prevalence of microsomal antibodies were similar and not significantly different in the three groups. On the other hand the prevalence of positive ADCC and CMAC tests was significantly greater, and at higher levels, in EU (ADCC THY CELLS 10.9 +/- 8.9% SL, ADCC Eye muscle = 25.9 +/- 20% SL, CMAC = 70.2 +/- 43% SL) and TX (ADCC THY CELLS = 9.3 +/- 9.2% SL, ADCC Eye muscle = 20.1 +/- 19% SL, CMAC = 62.4 +/- 30% SL) compared to GR (ADCC THY CELLS = 4.4 +/- 9.5% SL, ADCC Eye muscle = 7.7 +/- 6.7% SL, CMAC = 24.7 +/- 23% SL).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[Effects of Phytolacca acinosa polysaccharides I on cytotoxicity of macrophages and its production of tumor necrosis factor and interleukin 1].

The in vivo effects of Phytolacca acinosa polysaccharides I (PEP-I) on immunologic cytotoxicity of mouse peritoneal macrophages and its production of tumor necrosis factor (TNF) and interleukin 1 (IL-1) were studied. PEP-I 80, 160 mg/kg was given ip twice every 4 d. Both doses were found to have significant enhancing activity on macrophages cytotoxicity against S180 sarcoma cells and malignant transformed fibroblast L929 cells. Peritoneal activated macrophages were incubated with LPS for 2 and 24 h to induce TNF and IL-1, respectively. The TNF and IL-1 activities were tested from cytotoxicity against L929 cells in an absorbance assay of enzymatic reaction and proliferation of thymocytes co-stimulated assay separately. The optimal time for TNF production was found on d 8. Significant increases in TNF and IL-1 were observed. In comparison of the effect of PEP-I on TNF with that of known priming agent BCG, there was no difference between these two, but PEP-I had a high effect on IL-1. These results suggest that cytotoxicity of macrophages primed by PEP-I is closely related to its TNF and IL-1 production.

Animals↗
PubMed1983

Particular features of cell-mediated immunity in patients with anaplastic gliomas. A comparison with kidney and bladder cancer patients.

The authors studied 24 patients affected by anaplastic gliomas in regard to the killer (Antibody-Dependent Cellular Cytotoxicity) and natural killer (Spontaneous Lymphocyte-Mediated Cytotoxicity) immunological functions, by counting the Cr51 release in Change liver and K 562 cell cultures, respectively. These parameters were also evaluated in 24 healthy donors as control, in 24 patients affected by bladder cancer and in nine cases of kidney cancer. Our data show, pre-operatively, a statistically significant impairment of ADCC and SLMC activity in glioma patients as compared both with controls, bladder and kidney cancer patients. The particular impairment of K and NK functions in gliomas is discussed with regard to the specific features of Central Nervous System malignancies. An improvement of ADCC activity was also found in the post-operative samples. This finding confirms other reports about partial restoring of altered immunocompetence after surgery, suggesting a link between extention of tumor mass and impaired immunological reactions.

Adult↗