Hypothyroidism after treatment with interleukin-2 and lymphokine-activated killer cells

The development of a goiter and hypothyroidism in a 28-year-old man in whom metastatic melanoma had been treated with interleukin-2 and lymphokine-activated killer cells (LAK cells) prompted us to assess thyroid function in patients undergoing this therapy. Thirty-four patients with advanced neoplasms who had received interleukin-2 and LAK cells were followed for at least four weeks after treatment. Seven patients (21 percent) had laboratory evidence of hypothyroidism, with a decline in the serum thyroxine concentration to below normal (less than or equal to 35 nmol per liter; normal, 65 to 148), a decline in the serum free thyroxine index, and a rise in the serum thyrotropin concentration (peak values, 7.2 to 166 mU per liter; normal, 0.5 to 5.5) 6 to 11 weeks after treatment. Two patients had elevated serum thyrotropin levels before treatment, which increased further after treatment. In two patients, these abnormal values returned to normal within 10 months. All five symptomatic patients had borderline or elevated serum antimicrosomal antibody titers after treatment; two had serum antibodies to thyroglobulin. Five of the seven patients with hypothyroidism (71 percent) but only 5 of the 27 euthyroid patients (19 percent) had evidence of tumor regression (P less than 0.02). None of 11 patients treated with interleukin-2 but not LAK cells had hypothyroidism. We conclude that treatment with interleukin-2 and LAK cells can cause hypothyroidism, possibly by exacerbating preexisting autoimmune thyroiditis, and that it may be associated with a favorable tumor response.     

Surface characteristics, morphology, and ultrastructure of human adherent lymphokine-activated killer cells

Human adherent lymphokine-activated killer (A-LAK) cells represent a population of highly cytotoxic, interleukin-2 (IL-2)-activated peripheral blood lymphocytes that have large granular lymphocyte (LGL) morphology and display natural killer (NK) cell-associated surface markers (CD3-CD56+). The ultrastructure of A-LAK cells also is consistent with that of highly activated NK cells. After their initial isolation, continued culture of A-LAK cells in the presence of IL-2 resulted in cyclic shifts between adherent and non-adherent phases with about 90% of the cells floating and non-adherent. All of these A-LAK cells were spheroidal with numerous villi and pseudopodia. In the adherent phase, A-LAK cells were motile, moving along the solid surface at a speed of about 1 micron per minute, and polar, with a ruffled leading edge at one end of the cell and a terminal tuft of villi at the opposite end. Transmission electron microscopy of these cells also demonstrated a high degree of internal polarity, with the nucleus at the leading edge of the cell and richly granulated cytoplasm at the terminal end. Extensive cytoskeletal structures, multivesicular bodies, and an active Golgi complex characterized these cells. A-LAK cells in the adherent phase were found to express numerous point contacts (podosomes) and larger adherence structures containing polymerized actin, which appear to be important for interactions of these cells with the substrate. Increased expression of adhesion molecules in association with surface structures mediating adherence is also responsible for effective binding of A-LAK cells to solid surfaces.     

Appearance of neuropeptides in ascitic fluid after peritoneal therapy with interleukin-2 and lymphokine-activated killer cells for intraabdominal malignancy

Administration of intravenous interleukin-2 (IL-2), followed by intraperitoneal IL-2 and autologous lymphokine-activated killer (LAK) cells to six patients with colonic, ovarian, or endometrial carcinoma restricted to peritoneal spread increased significantly the ascitic fluid concentrations of the neuropeptides substance P (SP) and calcitonin-gene related peptide (CGRP). After intravenous IL-2 alone, the level of SP rose 10- to 140-fold, without a change in that of CGRP. Intraperitoneal IL-2 and LAK cells led to elevations in the concentrations of SP and CGRP to respective maximal means of 319 and 175 pM after 8 hr, which were maintained for 24–48 hr without alterations in the levels of vasoactive intestinal peptide or somatostatin. SP and CGRP from peritoneal fluid were chromatographically indistinguishable from synthetic neuropeptides. The increases in concentrations of SP and CGRP after IL-2 and LAK-cell therapy are the first demonstration of a neural response to a human cellular immunological reaction. The time course and magnitude of the neuropeptide response suggest a role in the vascular side effects of this form of treatment.     

Immune reactions induced by interleukin-2 transfected colorectal cancer cells in vitro: predominant induction of lymphokine-activated killer cells

One aim of the genetic modification of tumor cells is the generation of immunogenic variants that can be used for the induction of immune responses against tumors. We engineered the human colorectal carcinoma cell line SW480 by means of plasmid transfection to secrete interleukin (IL)-2. Transfection of SW480 cells resulted in stable IL-2 secretion at 5–30 ng/ml per 10⁵ cells in 24 h and, unexpectedly, in CD54 expression on the cell surface. SW480 variants expressing IL-2 and CD54 were tested for their capacity to induce T lymphocyte activation in vitro in comparison to untransfected and CD54 transfected cells. The cytolytic effector function of a class I MHC restricted CD8⁺, peptide antigen specific T cell clone was augmented following expression of CD54. IL-2 secreting SW480 variants did not further increase antigen-dependent cytolysis. Primary activation of resting T lymphocytes was assessed following allogeneic stimulation. When compared with unmodified SW480 cells, CD54 expressing variants did not initiate T cell proliferation. In contrast, IL-2 secreting SW480 cells strongly promoted primary T cell proliferation. Similarly, exogenous IL-2 and SW480 cells induced T cell pro liferatiowhich was not only due to IL-2 but was depen dent on tumor cells. However, following the initial wave of cell growth in response to IL-2 secreting SW480 cells T lymphocytes could not be restimulated with SW480 or IL-2 secreting variants and could not be further expanded. T cells initially activated by IL-2 secreting SW480 cells exhibited cytolytic activity towards SW480 cells. This reactivity, however, was transient and completely blocked by K562 cells, suggesting MHC-unrestricted, nonspecific cytotoxicity. We conclude that endogenous IL-2 secretion by the colorectal carcinoma cell line SW480 does not result in the activation of MHC restricted specific T lymphocytes but predominantly induces lymphokine-activated killer cells. Considering that tumor cell vaccines are aimed at inducing tumor-specific immune responses, our in vitro observation would rather argue against the in vivo application of such a tumor cell modification in colorectal cancer.Abbreviations IL Interleukin - LAK Lymphokine-activated killer - PBMC Peripheral blood mononuclear cells     

Role of prolactin in the in vitro development of interleukin-2-driven anti-tumoural lymphokine-activated killer cells.

Exogenous prolactin (PRL) has been shown to synergize with low-dose interleukin-2 (IL-2) and induce the proliferation and lymphokine-activated killer (LAK) maturation of natural killer (NK) cells. PRL itself can also generate LAK activity. Here we show that its local production occurs during, and is necessary for, LAK development. IL-2-stimulated peripheral blood mononuclear cells (PBMC) and purified NK cells were exposed to anti-human (h)PRL antiserum, and residual LAK activity was measured on day 7 against the promyelocytic leukaemia cell line HL-60. Inhibition of LAK activity was much more evident in PBMC compared with NK cell cultures (47% decrease. P - 0.013 and 18.5% decrease. P = 0.048, respectively). Up-modulation of a 32S-methionine-labelled 27,000 MW protein was detected in the lysates and supernatants of IL-2-stimulated PBMC immunoprecipitated with an anti-PRL antiserum. By contrast, the cytoplasmic PRL immunoreactivity observed in freshly isolated NK cells and in IL-2-stimulated, but not unstimulated, NK cell cultures was not associated with PRL gene activation, and can thus be referred to internalized PRL. Preferential re-uptake of externally derived PRL by IL-2-stimulated NK cells was also indicated by up-modulation of the PRL receptor. These data, as a whole, indicate that the PRL promotion of LAK differentiation is mainly mediated by paracrine secretion, with a minor contribution from internalized PRL.     

In vivo boosting of lung natural killer and lymphokine-activated killer cell activity by interleukin-2: comparison of systemic, intrapleural and inhalation routes.

Natural killer (NK) cells are thought to play a role in host defence against malignancy and infection, in immunoregulation and as precursor cells in a generation of lymphokine-activated killer (LAK) cells which can lyse NK-resistant tumour cells. As the lung is a major site for malignancy and infection and as there are large numbers of lymphoid cells including NK cells in the interstitial compartment of the lung, we evaluated the capacity of interleukin-2 (IL-2), a lymphokine capable of augmenting NK activity in vitro, to augment lung NK cell activity in vivo, using different routes of IL-2 administration. We compared both systemic (i.v. and i.p.) and local (intrapleural and inhalation) routes of IL-2 administration (50,000 U/daily for 5 days) using CBA mice, assessing NK and LAK cell activity in the spleen (systemic) and in the lung. The target cells used for these studies were the YAC-1 (NK-sensitive) and P815, NO36 and HA56 (NK-resistant, LAK-sensitive) cell lines. Splenic NK activity was increased by 1.4-1.9-fold for i.v./i.p., respectively, compared with controls with both systemic routes of administration, and lung NK activity was increased 3.2-fold and 3.8-fold (i.v./i.p, respectively, P less than 0.05), to levels which were comparable to systemic (splenic) NK activity following the same therapy. Intrapleural IL-2 administration similarly enhanced lung NK activity (3.3-fold) and splenic NK activity (1.3-fold; P less than 0.05 versus controls for both). Surprisingly, inhaled IL-2 suppressed both splenic and lung NK cell activity (84 +/- 8% and 78 +/- 10% suppression, respectively, P less than 0.05). LAK cell activity was also enhanced in the lung by 1.8-8-fold in response to i.v., i.p. and intrapleural IL-2, whereas inhaled IL-2 was ineffective in generating LAK cell activity. These results suggest that the systemic and intrapleural administration of IL-2 effectively boost pulmonary NK and LAK activity whereas inhalation of IL-2 does not. Thus, in clinical situations where boosting of local lung NK or LAK cell activity is desired, these routes of IL-2 administration may be effective.     

A progress report on the treatment of 157 patients with advanced cancer using lymphokine-activated killer cells and interleukin-2 or high-dose interleukin-2 alone

We studied the effects of adoptive immunotherapy with lymphokine-activated killer (LAK) cells plus interleukin-2 or therapy with high-dose interleukin-2 alone in 157 patients with metastatic cancer for whom standard therapy had proved ineffective or no standard effective treatment was available. One hundred eight patients were treated with 127 courses of LAK cells plus interleukin-2, and 49 patients were treated with 53 courses of high-dose interleukin-2 alone. Of 106 evaluable patients receiving LAK cells plus interleukin-2, 8 had complete responses, 15 had partial responses, and 10 had minor responses. The median duration of response was 10 months among those with complete responses and 6 months among those with partial responses; the patient with the longest complete response was still in remission 22 months after treatment. Of 46 evaluable patients treated with high-dose interleukin-2 alone, 1 had a complete response (remission greater than 4 months), 5 had partial responses (2, greater than 3, greater than 5, 7, and greater than 11 months), and 1 had a minor response. Seven of the total of nine complete responses still remain in remission. Hypotension, weight gain, oliguria, and elevation of bilirubin and creatinine levels were common, but these side effects resolved promptly after interleukin-2 administration was stopped. There have been four treatment-related deaths among these 157 patients. This immunotherapeutic approach can result in marked tumor regression in some patients for whom no other effective therapy is available at present. Determining its ultimate role in cancer therapy awaits further attempts to increase the therapeutic efficacy of treatment and decrease its toxicity and complexity.     

Observations on the systemic administration of autologous lymphokine-activated killer cells and recombinant interleukin-2 to patients with metastatic cancer

We describe here the preliminary results of the systemic administration of autologous lymphokine-activated killer (LAK) cells and the recombinant-derived lymphokine interleukin-2 to patients with advanced cancer. This regimen was based on animal models in which the systemic administration of LAK cells plus interleukin-2 mediated the regression of established pulmonary and hepatic metastases from a variety of murine tumors in several strains of mice. We treated 25 patients with metastatic cancer in whom standard therapy had failed. Patients received both 1.8 to 18.4 X 10(10) autologous LAK cells, generated from lymphocytes obtained through multiple leukaphereses, and up to 90 doses of interleukin-2. Objective regression of cancer (more than 50 per cent of volume) was observed in 11 of the 25 patients: complete tumor regression occurred in one patient with metastatic melanoma and has been sustained for up to 10 months after therapy, and partial responses occurred in nine patients with pulmonary or hepatic metastases from melanoma, colon cancer, or renal-cell cancer and in one patient with a primary unresectable lung adenocarcinoma. Severe fluid retention was the major side effect of therapy, although all side effects resolved after interleukin-2 administration was stopped. Further development of this approach and additional patient follow-up are required before conclusions about its therapeutic value can be drawn.     

Immune responses in humans while receiving adoptive immunotherapy with recombinant interleukin-2 and lymphokine-activated killer cells: acute anergy to mitogens and recall antigens

In this study we evaluated the in vitro immunologic responses of 11 patients receiving immunotherapy with either interleukin-2 (IL-2, 3 X 10(6) units/m2) or IL-2 plus lymphokine-activated killer cells (LAK) over a 30-day period. Blastogenic responses to mitogens or recall antigens were found to significantly decrease during therapy. Pokeweed mitogen immunoglobulin (Ig) production decreased significantly in 7 patients or showed no change. In vivo skin tests for cell-mediated immunity were also performed and the average number of positive responses before IL-2/LAK therapy decreased to no positive responses (day 29 of therapy). Experiments were performed to determine whether decreased responses were a result of active suppression or a dilution effect by immature/mature cells that cannot respond to mitogen or antigen. Pre-therapy cells were mixed with fresh autologous (anergic) cells from day 29 of therapy in varying ratios. Blastogenesis and Ig production was measured. Our findings demonstrate that the decreased immune response observed during and after therapy is a result not of active immunosuppression but rather of a dilution effect by cells with immune dysfunction. We conclude that: (1) in vitro blastogenesis or Ig production tests using mitogens or antigens for patients undergoing IL-2 immunotherapy have no predictive value, and (2) the immune cells that are present are refractory.     

Cytotoxic activity of interleukin-2 (IL-2) activated killer cells toward thyroid epithelial cells

We investigated the sensitivity of thyroid epithelial cells (thyrocytes) to IL-2 activated killer cells. The thyrocytes were lysed by autologous and allogeneic IL-2-activated killer cells; there were no differences in sensitivity to the killer cells between normal thyrocytes and thyrocytes from patients with Graves' disease. When thyrocytes were pretreated with recombinant interferon (rIFN) gamma or alpha, the IL-2-activated killer cell-mediated cytotoxicity was depressed and varied inversely with the cell surface expression of class I HLA gene products. The rIFN-gamma pretreatment did not alter the kinetics of thyrocytes lysis by IL-2-activated killer cells. Using cold target competition analysis, rIFN-gamma-pretreated thyrocytes clearly competed less effectively than did untreated cells for lysis of untreated target cells. These results suggest that rIFN-gamma or IFN-alpha pretreatment of thyrocytes may reduce their ability to be recognized by effector cells. These findings suggest that destruction of thyrocytes in autoimmune thyroiditis may be, in part, due to IL-2-activated killer cells and may be regulated by IFN.     

Interleukin-4 differentially regulates interleukin-2-mediated and CD2-mediated induction of human lymphokine-activated killer effectors.

Natural killer (NK) cells can be differentiated into lymphokine-activated killer (LAK) effectors following stimulation with interleukin (IL)-2. This induction can be negatively regulated by IL-4. In this study, we demonstrate that the stimulation of NK cells through the CD2 pathway with (9-1 + 9.6) monoclonal antibodies can also induce these cells to secrete tumor necrosis factor-alpha (TNF-alpha) and to differentiate into LAK effectors. More importantly, our data indicate that, in contrast to the IL-2-induced LAK generation, the anti-CD2-triggered LAK activity was not regulated by IL-4. IL-4 was found to enhance the LAK activity as well as NK cell proliferation following activation with anti-CD2 by a mechanism involving, at least in part, an increased TNF-alpha production. Using immobilized monoclonal antibodies against the Fc receptor (Fc gamma RIII or CD16) for NK stimulation, we also observed that the anti-CD16-induced LAK activity was not inhibited by IL-4. These data further point to a pivotal role of TNF-alpha as a regulatory cytokine in anti-CD2-induced LAK generation, and suggest that IL-4 could serve as a discriminatory factor between two distinct pathways involved in the activation of non-MHC-restricted cytotoxicity.     

Defective interleukin-2 induction of lymphokine-activated killer (LAK) activity in peripheral blood T lymphocytes of patients with monoclonal gammopathies.

The recombinant interleukin-2 (rIL-2) generation of lymphokine-activated killer (LAK) cells was investigated in peripheral blood T lymphocytes (PBT) of 16 patients with monoclonal gammopathy of undetermined significance (MGUS) and 32 patients with multiple myeloma (MM). LAK activity was significantly decreased in MM, but not in MGUS patients, and was partially recovered in MM in the remission phase. This finding was unexpected, because CD8+ CD11b+ cells, which contain LAK precursors, are significantly increased in MM. LAK activity was investigated in purified CD8+ CD11b+ lymphocytes to discriminate between an intrinsic defect or a defective regulation by other T cell subsets. These cells were intrinsically unable to generate LAK activity fully following rIL-2 stimulation. MM showed the more pronounced LAK deficiency, while MGUS patients showed intermediate values. Phenotyping revealed significantly increased proportions of Leu7+ and HLA-DR+ cells in MM patients. These data reveal another dysregulation of T cell effector functions in patients with monoclonal gammopathies and offer further evidence of the impairment of their cell-mediated immunity.     

Evidence that induction and regulation of lymphokine-activated killer (LAK) activity are mediated by changes in tumour-binding potential of lymphocytes after activation by interleukin-2 (IL-2).

The changes in the tumour-binding potential of human peripheral blood lymphocytes (PBL) after activation by interleukin-2 (IL-2) was investigated by directly counting the number of lymphocytes bound to lined hepatoma cell monolayers. A significant increase in the tumour-binding potential of PBL was found after activation by more than 100 U/ml of IL-2. Maximal tumour-binding potential was achieved at 1000 U/ml of activation, and an overdose of IL-2 activation slightly decreased this potential. These changes were almost exactly the same as the changes in anti-tumour cytotoxicity as measured by a 4-hr 51Cr-release assay. In addition, the kinetics of tumour binding by lymphokine-activated killer (LAK) cells was shown to be almost identical to that of tumour cell lysis. These results thus provide evidence that induction and regulation of LAK activity are mediated by changes in tumour-binding potential of lymphocytes after activation by IL-2.     

Comparison of suppressor and cytotoxic activity of blood mononuclears during adaptive immunotherapy of cancer patients with lymphokine-activated killer cells with a low dose of recombinant interleukin-2

Laboratory of Cellular Immunity, Department of Blood Transfusion, All-Union Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Trapeznikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 11, pp. 519–521, November, 1991.     

Induction of endogenous lymphokine-activated killer activity by combined administration of lentinan and interleukin 2

Lymphokine-activated killer activity in vivo (endogenous LAK activity) was found to be augmented by combined administration of lentinan, a beta (1-3) glucan with beta-1,6 branches, and interleukin 2 (IL-2). In contrast, addition of lentinan during culture in vitro did not augment LAK activity induced by IL-2. Surface marker analysis of endogenous LAK cells revealed that endogenous LAK cells induced by a combined administration of lentinan and IL-2 were all NK-type LAK cells, which express asialo-GM1 and lack T3, Thy-1 and Lyt2, whereas LAK cells generated in vitro were composed of both NK-type LAK and T-type LAK cells, which express T3 and Thy-1, and lack asialo-GM1. Furthermore, combined administration of lentinan and IL-2 was found to augment the endogenous LAK activity even in the tumor bearer, and show a substantial inhibition of tumor growth and a significant increase in survival rate in the C3H/HeN/MM46 system. Results of the present investigation offer a possible clinical application of a combination of lentinan and IL-2 for immunotherapy against cancer without detrimental side effects.     

Bone marrow granulomas in acute myeloid leukaemia following interleukin 2 and lymphokine-activated killer cells

Granulomas are thought to represent an immune reaction to antigenic stimulation. Bone marrow granulomas are uncommon, but in the following case report we show their transient appearance after interleukin 2 (IL-2) and autologous lymphokine-activated killer cell therapy. This is a previously unreported association, and may implicate IL-2 in the pathogenesis of granulomas.     

Enhanced induction of lymphokine-activated killer activity after lentinan administration in patients with gastric carcinoma.

In 15 patients with gastric carcinoma, peripheral blood mononuclear cells (PBM) were obtained serially before and 3, 5 and 7 days after lentinan administration. The generation of lymphokine-activated killer (LAK) activity, induced by in vitro activation of PBM with interleukin 2 (IL 2), was significantly augmented 5 days after a single intravenous dose of 2 mg lentinan, when compared with that before lentinan injection. Natural killer (NK) activity of PBM was also significantly enhanced 7 days after the drug injection. However, the distribution of lymphocyte subsets exhibited no significant change following lentinan administration.     

Generation and characterization of a monoclonal antibody that recognizes an activation antigen expressed by a majority of adherent lymphokine-activated killer cells

In an attempt to generate murine natural killer (NK) cell-specific monoclonal antibodies (MAbs) by immunizing Balb/c mice with C57BL/6 (B6) A-LAKs, we have isolated a hybridoma, CS/NicT.2, which secretes an IgM that recognizes a majority of B6 and B6 Rag-1-/- A-LAKs. The CS/NicT.2 antigen is highly expressed by A-LAKs, but only at extremely low levels on resting splenocytes, suggesting that its expression is tightly associated with IL-2 activation. Among the cell lines examined, only CTLL-2 expresses the CS/NicT.2 antigen at relatively high levels. A low level of CS/NicT.2 staining is also detected on resting allo-specific cytotoxic T lymphocytes (CTL) clones, AB.1 and C11. In addition, a similar low level of CS/NicT.2 staining is detected on the T-helper cell line HT-2. The CS/NicT.2 antigen is upregulated by ionomycin but not by phorbol 12-myristate 13-acetate (PMA). For the CTL clones examined, CS/NicT.2 staining is also dramatically increased by anti-TCRbeta or anti-CD3epsilon stimulation. Protease treatments of CTLL-2 show that this antigen is proteinase K sensitive, but relatively resistant to trypsin digestion. Furthermore, the CS/NicT.2 antigen exhibits a relatively fast turnover rate as assessed by proteinase K and cycloheximide treatments of CTLL-2, suggesting that the CS/NicT.2 antigen may have a short half-life on the cell surface.