Cytotoxicity In Patients Research Articles

In vitro effect of lymphoblastoid α-interferon on subpopulations of effector cells mediating cytotoxicity for autologous hepatocytes in hepatitis B and non-A, non-B

Controlled clinical trials are currently under way to assess the efficacy of interferon (IFN) in hepatitis B virus (HBV) infection. In the present study, T-enriched and non-T-enriched lymphocytes from six patients with acute and six patients with chronic HBV infection were cocultured with autologous liver cells with and without α-IFN (lymphoblastoid) at a concentration of 1000 U/ml of culture medium, in an 18 h cytotoxicity assay. IFN produced a significant enhancement of non-T-cell cytotoxicity in patients with acute and chronic HBV infection, from 34.3 ± 19.6% to 60.0 ± 11.2%, P<0.03, and from 41.2 ± 17.2% to 65.5 ± 9.8%, P<0.01, respectively. In contrast, no significant effect was observed on T cell-mediated cytotoxicity in either group of patients. The in vitro effect of α-IFN was also evaluated in four patients who developed chronic non-A, non-B hepatitis following blood transfusion, but no significant stimulatory effect was noted on either T- or non-T cell cytotoxicity. Similarly, no significant increase was observed in control subjects. The significant enhancement of non-T cell cytotoxicity, but not of T-cell cytotoxicity, for autologous hepatocytes in HBV infection suggests that α-IFN produces a selective stimulatory effect on non-T cells. The absence of a similar effect in patients with chronic non-A, non-B hepatitis and control subjects suggests that HBV infection alters the susceptibility of hepatocytes to IFN-stimulated non-T cell damage.

Systemic and regional natural cytotoxicity in patients with head and neck cancer

Forty patients with squamous carcinoma of the oral cavity (head and neck cancer) were investigated for natural killer-cell (NK) activity in peripheral blood (PB) and tumour-draining lymph nodes (LNs). For measuring NK activity a 4 hrs 51Cr release assay and K 562 target cells were used. Mononuclear cells of PB (PBMNC) and LNs (LNMNC) were separated by Ficoll Hypaque gradient centrifugation. NK activity was determined before tumour surgery. LNs were obtained either at the time of surgery of the primary tumour (en bloc neck dissection)--"immediately dissected LNs (ID-LNs)" or some time after removal of the primary tumour, especially for prophylactic purposes,--"delayed dissected LNs (DD-LNs)". Preoperatively, NK activity was clearly stage-dependent, patients with stages T1-2 displaying mean values similar to those of a control group without malignant disease, whereas values were significantly lower in patients with stages T3-4. Spontaneous cytotoxicity was significantly lower in LNMNC than in PBMNC of identical donors. NK activity was significantly lower in ID-LNs than in DD-LNs. These results suggest some negative influence of the primary tumour in the spontaneous cytotoxicity in both PB and tumour-draining LNs. In vitro incubation at +37 degrees together with addition of lymphoblastoid interferon (IFN-alpha) achieved a significantly stimulation of NK activity in both PBMNC and LNMNC.

An assessment of natural cell-mediated cytotoxicity in patients with malignant lymphoma

Fifty per cent of untreated malignant lymphoma patients were shown to have profoundly reduced levels of peripheral blood lymphocyte-natural cell mediated cytotoxicity (PBL-NCMC) when tested against the leukaemic cell-line K562; assessment of NCMC in unfractionated blood from a large number of these patients showed a comparable reduction in activity. High levels of NCMC were observed in some patients with stage III/IV non-Hodgkin's lymphoma (NHL), while Hodgkin's disease (HD) patients over 40 yr of age had normal levels. In both NHL and HD patients there was no correlation between NCMC and absolute lymphocyte count or lymphoma histology. Human interferon was seen to boost NCMC in the majority of NHL patients, but most HD patients were non-responders. Almost all patients tested had normal number of target binding lymphocytes, and most had numbers of HNK-1 + cells within the control range. However, on exposure to IFN, the number of target binding lymphocytes increased in over half of the patients tested, with some patients showing an increase in HNK-1 + cells, in the majority of cases without enhancement of NCMC.

In vitro cellular cytotoxicity for a human colon cancer cell line by mucosal mononuclear cells of patients with colon cancer and other disorders.

In vitro cellular cytotoxicity of mononuclear cells of intestinal mucosa and peripheral blood for a colon cancer cell target was measured in patients with colon cancer and other disorders requiring resection. Four- and 24-hour cytotoxicity assays were conducted using selenium 75 (75Se)-labeled RPMI-4788 human colon cancer target cells grown in culture. In the cancer group mean cytotoxicity was 30.4% at 24 hours for peripheral blood effectors and 8.0% for effectors from normal mucosa. Values in patients with Crohn's disease were 10.4% for blood and 17.2% for effectors from normal mucosa, and 13.6% and 18.5%, respectively, for blood and abnormal mucosa. Values in patients with other diseases were 25% for blood and 14.7% for mucosa. Mean cytotoxicity at 4 hours did not exceed 6.4% for any group, and assays in autologous serum gave results similar to tests in calf serum. In additional studies, K 562 chronic leukemia cells were somewhat more sensitive to lysis than RPMI-4788 by blood mononuclear cells, but there was no lysis of K 562 by mucosal populations that were cytotoxic for RPMI-4788. There was no competitive inhibition by either target cell for the other. It was concluded that 75Se RPMI-4788 colon cancer cells are suitable targets for evaluating in vitro cytotoxicity by intestinal mucosal cells and that mucosal cytotoxicity in patients with colon cancer is depressed compared to cytotoxicity by peripheral blood effectors.

Defective natural killer cytotoxicity and polymorphonuclear leukocyte antibody-dependent cellular cytotoxicity in patients with LFA-1/OKM-1 deficiency.

Four children with an immunodeficiency involving the absence of leukocyte membrane glycoproteins reacting with anti-LFA-1 and OKM-1 monoclonal antibodies were unable to mediate adherence-dependent leukocyte functions. Even with normal Fc receptor function, their PMN-ADCC and MC-NKC were markedly deficient. Single cell analysis demonstrated deficient antibody-mediated PMN-target cell adherence. Monoclonal antibodies against LFA-1 and OKM-1 reproduced this immunodeficiency in leukocytes from normal adults. LFA-1/OKM-1 mediates a PMN-target cell adhesive step.

The nature of enhanced natural killer lymphocyte cytotoxicity during anesthesia and surgery in patients with benign disease and cancer.

This study was instituted to determine the mechanism of enhanced natural killer (NK) lymphocyte activity during surgery. Natural cytotoxicity of whole blood to K562 target cells was assayed before anesthesia and during anesthesia and surgery in patients with benign and malignant gastrointestinal disease. Those patients with benign conditions and localized primary tumors showed enhanced NK lymphocyte cytotoxicity during surgery (p less than 0.025 and p less than 0.0025, respectively) but not patients with disseminated tumors. In patients with localized tumors, enhancement of NK lymphocyte cytotoxicity was an interferon-independent phenomenon but appeared to be related to a significant rise in the percentage of cells bearing the Leu 7 monoclonal antibody marker for NK cells (p less than 0.02). Exogenous leukocyte interferon caused further enhancement of NK cytotoxicity in patients with benign disease and some cancer patients. Enhancement of NK lymphocyte activity during surgery may be of significance in reducing tumor metastases by stimulation of natural cytotoxic mechanisms to circulating tumor emboli.

The effect of chemotherapy on lymphocyte subpopulations and cell-mediated cytotoxicity in patients with ovarian carcinoma

Chemotherapy using adriamycin with cyclophosphamide, and cyclophosphamide with hexamethylmelamine or with alkeran causes no significant reduction in the total lymphocyte count, in the percentage subpopulations of T cells and B cells or in mononuclear cell cytotoxicity in patients with Stage III carcinoma of the ovary during their first course of chemotherapy.

Natural killer-mediated cytotoxicity in patients with laryngeal carcinoma.

Natural killer (NK)-mediated cytotoxicity against the K562 cell line was evaluated in normal subjects and in patients with laryngeal cancer. Results showed reduced lymphocyte cytotoxicity in patients with neoplastic disease and further reduction in NK activity following postoperative radiation therapy. The authors discuss the possibility of using this test in the immunological monitoring of patients with laryngeal carcinoma.

Relationship between expression of hepatitis B virus antigens in isolated hepatocytes and autologous lymphocyte cytotoxicity in patients with chronic hepatitis B virus infection.

Previous studies demonstrated that peripheral blood lymphocytes are cytotoxic to autologous hepatocytes in patients with chronic hepatitis B virus infection. We examined whether cytotoxicity is specifically directed against hepatocytes expressing HBsAg or HBcAg. Viral antigens were detected by immunofluorescence in isolated hepatocytes before and after exposure to T and non-T lymphocytes from 28 patients with chronic HBV infection in an autologous cytotoxicity assay. There was significant reduction in the percentage of HBcAg-positive hepatocytes after exposure to T lymphocytes and, to a lesser extent, after exposure to non-T cells; hepatocytes expressing HBsAg were not affected. Other studies showed that many hepatocytes containing HBcAg have IgG of anti-HBc specificity bound to their nuclei. In the present study, there was significant association between the presence of HBcAg and nuclear IgG in isolated hepatocytes. The ratio between the percentages of HBcAg-positive and IgG-positive hepatocytes (reflecting the proportion of hepatocytes containing free-core antigen) correlated significantly with reduction in HBcAg-positive liver cells after exposure to T cells, but not to non-T cells. These results suggest that hepatocytes in which viral replication is occurring and which express core determinants are susceptible to cell-mediated cytotoxicity and that T-cell cytolysis may be modulated by anti-HBc which is bound to hepatocytes.

Analysis of Natural Killer Cell Cytotoxicity of Cancer Patients Treated With Recombinant lnterferon&lt;xref ref-type="fn" rid="FN2"&gt;2&lt;/xref&gt;&lt;xref ref-type="fn" rid="FN3"&gt;3&lt;/xref&gt;

Peripheral blood natural killer (NK) cell cytotoxicity of 24 cancer patients was studied prior to and after single and multiple injections of various doses of human leukocyte recombinant interferon-alpha clone A (IFN-alpha rA). The NK cell cytotoxicity of all cancer patients declined consistently 4 and 8 hours after a single injection of IFN-alpha rA. Twenty-four hours after the injection of IFN-alpha rA, NK cell cytotoxicity of patients with low NK cell phenotype (NK-LR) was significantly augmented, whereas that of patients with medium (NK-MR) or high (NK-HR) NK phenotype was depressed. After multiple injections of IFN-alpha rA, depression of NK cell cytotoxicity was observed in a number of NK-MR and NK-HR patients, but in some patients with NK-LR phenotype, further potentiation was observed. No direct correlation between the NK cell augmentation and serum IFN levels was detected. In in vitro studies, IFN-alpha rA, when added to cultures of target and effector cells of normal individuals in a dose of 10(3) U/ml, was efficient in augmenting NK cell cytotoxicity. NK cell cytotoxicity of cancer patients could also be augmented by the IFN-alpha rA preparation; however, this augmentation occurred only prior to in vivo IFN-alpha rA therapy. After IFN-alpha rA in vivo therapy, their NK cells became refractory to further in vitro IFN-alpha rA treatment.

Stimulation of Monocyte-Mediated, Antibody-Dependent Cytotoxicity in Mycosis Fungoides

Antibody-dependent cytotoxicity mediated by purified blood monocytes were determined in untreated patients with plaque-stage mycosis fungoides (MF), parapsoriasis en plaques, exfoliating erythroderma, and noncutaneous malignant lymphoma. Compared with healthy control subjects and control subjects with varicose ulcers, patients with MF had increased monocyte cytotoxicity. In the other dermatoses, normal monocyte cytotoxicity was found. Patients with noncutaneous malignant lymphoma showed normal or decreased monocyte cytotoxicity. There was no evidence that abnormal monocyte cytotoxicity in cutaneous and noncutaneous malignant lymphoma were caused by interaction with lymphocytes or serum. The presence of increased monocyte cytotoxicity in patients with plaque-stage MF may be a clinically useful finding when this diagnosis is suspected clinically but not proved histopathologically.

Natural cytotoxicity in patients undergoing radiation therapy

Natural cytotoxicity in patients undergoing radiation therapy

Natural cytotoxicity in patients undergoing radiation therapy

Natural cytotoxicity against K562 target cells was measured in 51 adults with solid epithelial malignant tumors who were untreated, in 42 patients who were studied within 6 weeks following completion of radiotherapy (4,000-7,000 rads), and in 27 normal subjects. In both the radiated and the nonirradiated groups, mean cytotoxicity for patients with localized cancers was not significantly different from that of the normal controls, whereas mean cytotoxicity for patients with advanced cancers was significantly lower than that for normal controls and patients with localized disease. Twelve percent of nonirradiated patients and 13% of radiated patients with localized tumors, but 46% of nonirradiated patients and 44% of irradiated patients with advanced cancers, failed to exhibit normal NK activity. Mean cytotoxicity for irradiated patients was not significantly different from that of untreated patients. PBL from most patients showed enhanced cytotoxicity after preincubation of PBL with interferon (IFN alpha). Mean cytotoxicities for nonirradiated and irradiated patients after IFN alpha pretreatment of PBL were not significantly different. In both patient groups, IFN alpha-boosted killing was significantly less in patients with advanced disease than in patients with local tumors or normals. These results indicated that radiotherapy has no significant effect on spontaneous or IFN alpha-boosted natural cytotoxicity.

Specificity of T lymphocyte cytotoxicity to autologous hepatocytes in chronic hepatitis B virus infection: evidence that T cells are directed against HBV core antigen expressed on hepatocytes.

Peripheral blood T lymphocytes from 21 patients with chronic HBV infection were incubated with autologous hepatocytes in a microcytotoxicity assay. Cytotoxicity was significantly increased in 13 cases, and in 12 of these the cytotoxic effect of the T lymphocytes was inhibited by preincubating the liver cells with IgG containing antibodies to the hepatitis B core antigen (HBcAg). Normal human IgG and IgG containing antibodies to the hepatitis B surface antigen (HBsAG) were without effect. Control experiments using autologous fibroblasts as target cells showed low levels of T cell cytotoxicity and no blocking effect of anti-core antibody. All patients in whom it was possible to demonstrate HBcAg in liver tissue had significantly increased T cell cytotoxicity to autologous hepatocytes. These studies suggest that T cell cytotoxicity in patients with chronic HBV infection is directed against determinants resembling the hepatitis B core antigen on the plasma membrane of hepatocytes.

Defective natural cytotoxicity in patients with cancer: normal number of effector cells but decreased recycling capacity in patients with advanced disease.

Patients with advanced cancer exhibited lower natural cytotoxicity against K562 target cells in a standard short-term chromium release assay than did patients with localized malignancy or normal individuals. Although natural killer (NK) activity of advanced cancer patients could be augmented by nylon column depletion of adherent cells and enriched further by fractionation of discontinuous Percoll gradients, the NK level attained remained below that obtained from PBL of normal donors treated by the same procedures. The pattern of NK activity obtained on the Percoll gradients was the same for all individuals studied. The proportion of large granular lymphocytes (LGL) paralleled NK activity and was highest in the peak NK fraction in all individuals tested. Advanced cancer patients with low NK activity showed no decrease in number of LGL from that of other cancer patients or normals. Similarly, there was no decrease in target binding cell number. Using a single-cell assay in agarose, we found that the number of active NK cells was the same for all patients, whether with localized or advanced malignancy, and normal subjects. In a 3-hr time period, there were no differences in the rate of killing in agarose. The maximum killing potential (Vmax) of the NK-deficient advanced cancer patients in a 51Cr-release assay was significantly lower than that of normals or other cancer patients. The observed defect in natural cytotoxicity of these patients thus appeared to be due to a reduced recycling capacity.

A study of antibody dependent cell-mediated cytotoxicity in patients with chronic active hepatitis

Immune mechanism of hepatocytes-in july in chronic liver diseases was studied. Live specific lipoprotein (LSP, Meyer zum Bizschenfelde) may play an important role in the chronic liver diseases, and that in chronic active hepatitis, a LSP-mediated antibody dependent cell-mediated cytotoxicity (ADCC) may established itself, which would serve as an immunopathogenic cause of liver cell injury.The K-cell populatin of peripheral blood, the effector cell of ADCC, was significantly decreased compared with that in normal subjects even in patients with demonstrated serum ADCC activity to hepatocytes. This decrease of K-cell population showed that serum inhibitory factors of K-cell exsists beside the antibodies which induce ADCC in patients serum by an underlying experiments.Analysis by Sephadex G 100 gel filtration of supernates from cultures of LSP-sensiti-zed peripheral lymphocytes from patients revealed a factor, recovered as a forth fraction, which proved capable of increasing the K-cell population.The results have also demonstrated the presence of an immunopathogenic mechanism whereby hepatocellular injury due to ADCC in chronic liver diseases, particularly in chronic active hepatitis is controlle by K-cells, the effector cells.

Spontaneous cell-mediated cytotoxicity in patients with transitional cell carcinoma of the urinary bladder

Lymphocytes isolated from the blood of TCC patients, like those of control patients, were capable of mediating spontaneous cell-mediated cytotoxicity against K-562 cells. When this natural cytotoxicity was analyzed with regard to the effector cell type it was found that in TCC patients the SLMC was mostly displayed by E-rosetting T lymphocytes, whereas compared with controls, a significant decline in the SLMC of the non-T lymphocytes was observed. The SLMC of the T lymphocytes derived from TCC patients was further demonstrated on a T leukemia target cell (Peer). When the SLMC on K-562 and on Peer target cells was compared, a specificity difference was observed between TCC and the control patients' effector cells. The SLMC activity of the TCC patients' T cells was not abolished after depletion of Fc receptor-positive cells or following treatment with monoclonal antibodies OKT 8 or OKT 4 and complement (C'). These NK-like cells are therefore distinguished from cytotoxic T lymphocytes and NK cells.

Decreased antibody-dependent and spontaneous cell-mediated cytotoxicity in patients with chronic renal failure

Antibody-dependent and spontaneous lymphocytotoxicity of blood mononuclear cells from 15 patients with chronic renal failure was studied in allogeneic K-562 and xenogeneic chicken erythrocyte test systems. Both antibody-dependent and spontaneous cytotoxic activities were significantly decreased in uremic patients as compared to the corresponding mean values of healthy control persons and non-uremic patients with the same underlying diseases. The addition of autologous serum further reduced the impaired cytotoxic capacity of uremic lymphocytes. Uremic sera also inhibited the antibody-dependent and spontaneous lymphocytotoxicity of healthy individuals.

Natural Cytotoxicity of Peripheral Blood Lymphocytes and Regional Lymph Node Cells in Breast Cancer in Women&lt;xref ref-type="fn" rid="fn2"&gt;2&lt;/xref&gt;&lt;xref ref-type="fn" rid="fn3"&gt;3&lt;/xref&gt;

Natural cytotoxicity was studied before surgery or other treatment in 83 women with primary, untreated breast cancer. Peripheral blood lymphocytes (PBL) and cytotoxicity of regional lymph node cell(s) (RLNC) were examined in a 4-hour 51Cr release assay against the target cell K-562. Results indicated that greater than one-third of breast cancer patients have more negative lymphocyte cytotoxic activity toward K-562 than do the other two-thirds. Similar results were observed for PBL of 25 patients found to have benign breast lesions. Of these patients, 23 had fibrocystic disease. The difference between these findings and findings with normal control lymphocytes studied in parallel was highly significant (P less than 0.001). The study of RLNC cytotoxicity in patients with breast cancer showed that 25% of the patients' RLNC had significant natural cytotoxic activity toward K-562. Incubation of RLNC with interferon in vitro before addition of labeled K-562 cells did not induce cytotoxicity in RLNC that did not have this activity initially.

Kinetics of natural cytotoxicity in patients treated with human fibroblast interferon

Short- and long-term effects of IV administration of human fibroblast interferon (HFIF) on natural cytotoxicity was studied in patients with HBsAg-positive chronic active hepatitis. Short-term kinetics demonstrated a transient decrease of natural cytotoxicity, when measured 2 or 4 h after IV administration of HFIF (1−10×106 U/injection). Twenty-four hours after the initial injection of HFIF natural cytotoxicity was increased to 196%–282% of pretreatment values. The kinetics of NK activity during chronic stimulation with HFIF revealed the following features: (a) The highest relative increase was seen during the initial phase of HFIF application; (b) enhanced NK activity could be maintained for 2–4 weeks of therapy; (c) at a plateau of high activity short-term increases were much less pronounced; (d) in all patients monitored so far over a period of several weeks a gradual decrease of augmented NK activity has been observed despite continued administration of high doses of HFIF.