PubMed Health⌕ Search

Biomedical subjects

S Ferrini

Publications and source records attributed to S Ferrini.

At least 55 records · Page 3Linked to original sources
PubMed1997

Reciprocal expression of CD70 and of its receptor, CD27, in human long term-activated T and natural killer (NK) cells: inverse regulation by cytokines and role in induction of cytotoxicity.

By transfection of COS cells with an expression vector containing CD70 cDNA we demonstrate that two previously described MoAbs (ED6 and LD6) recognize CD70. By means of these MoAbs, we show that the surface expression of CD70 inversely correlates with the expression of its receptor, CD27, on activated T and NK cell populations and clones, although a subpopulation of cells expressing low density of both molecules exists. In addition, culture in the presence of IL-4 significantly enhances CD27 and reduces CD70 surface expression in phytohaemagglutinin (PHA)-activated peripheral blood lymphocytes (PBL), while tumour necrosis factor-alpha (TNF-alpha) displays opposite effects, indicating that receptor and ligand are reciprocally regulated by these cytokines. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of CD27 and CD70 mRNA suggests a transcriptional control of CD27 antigen expression in T cell clones. In addition, we show by the use of a re-directed killing assay that in cytotoxic T cell receptor (TCR) alpha/beta+ T cell clones, CD27 molecule may be involved in the regulation of cytolytic functions and may act synergistically with CD2. Finally, CD70 also acts as a signal-transducing molecule in some activated CD70+ TCR gamma/delta+ T or NK cell clones. In conclusion, our data indicate that CD27 and CD70 molecules are differentially expressed and regulated on long term-activated T and NK cells and are involved in the control of cellular functions.

Antibodies, Monoclonal↗
PubMed1997

Role of interleukin (IL)-2 and IL-15 in the tumour progression of a melanoma cell line MELP, derived from an IL-2 progressor patient.

MELP is an interleukin (IL)-2 receptor (IL-2R; alpha+ beta+ gamma-) melanoma cell line that was derived, before the beginning of the immunotherapy, from a patient whose metastasis increased in size during treatment with IL-2/interferon-alpha. In these cells, continuous culture in the presence IL-2 (1000 UI/ml) causes the selection of a cell sub-line (termed MILG) expressing the gamma-chain which is tumorigenic in nude mice. Here, we further analysed the characteristics of MELP and MILG cells as well as clones selected at limiting dilution in the presence of high concentrations of IL-2 or IL-15, or those selected after transfection for the expression of a human IL-2 transgene (MELP-CL1). MELP cells, but not six other melanomas cell lines, shed two soluble immunosuppressive molecules, CD25 and intercellular adhesion molecule-1, whose levels also strongly increase in vivo during immunotherapy. In vitro MELP cells express transcripts for IL-6, transforming growth factor, basic fibroblast growth factor and vascular-endothelial growth factor. Cloning at limiting dilution was obtained in culture fed with IL-2 or IL-15. All these clones, as MILG cells, express the transcript for the IL-2R gamma chain. This could favour improved interactions with cytokines using this chain. By contrast, MELP-CL1 cells, which secrete low amounts of biologically active IL-2 (200 UI/10(6) cells) exhibit a phenotype and growth characteristics similar to those of the parental MELP cells. Indeed, a crosslinking experiment with 125I-IL-2, has showed that MELP and MELP-CL1 cells display a scant IL-2 binding ability that is strongly increased in MELP cells fed for 1 week with 1000 UI/ml IL-2. These cells, as well as MILG cells express a betagamma-complex which can also bind IL-15. IL-2 induces a rapid tyrosine phoshorylation in MILG cells, which is followed by a prolonged induction of c-fos and c-jun genes. By contrast, in MELP cells IL-2 only causes a delayed induction of c-myc gene. All MELP derivatives, but not MILG cells, express the transcripts for IL-15, which is not secreted but is present as an intracellular protein. All MELP cells express the transcript for the IL-15R alpha chain. MELP-CL1 cells are not tumorigenic in nude mice, whereas MILG cells form rapidly growing tumours in 75% of the mice. Coinjection at the same site of MILG and MELP-CL1 cells causes the rapid regression of MILG tumours in 80% of the mice, whereas their bilateral injection causes the rapid development of MILG tumours in 100% of the nude mice. Finally, treatment in nude mice of MILG cells with low amounts of IL-2 (1000 UI per mouse) and IL-15 (50 ng per mouse) induces the development of much more aggressive tumours.The expression of functional IL-2Rs in a subset of human melanomas could be responsible for tumour progression.

Adult↗
PubMed1996

Identification of a novel interleukin-15 (IL-15) transcript isoform generated by alternative splicing in human small cell lung cancer cell lines.

IL-15 is a cytokine promoting growth and differentiation of T, B and NK lymphocytes. By RT-PCR analysis, using primers allowing amplification of the entire IL-15 mRNA coding region, 9/11 small cell lung cancer (SCLC) cell lines displayed detectable IL-15 gene expression. In addition to the expected band sizing 524 bp, a larger band was also observed. Cloning and sequence analysis of the larger cDNA from two SCLC cell lines revealed a size of 643 hp due to the presence of additional 119 hp within the previously reported IL-15 cDNA sequence. The 119 hp sequence matched with an IL-15 genomic sequence downstream the IL-15 second coding exon and may represent a previously unreported alternative exon (exon A). The SCLC-associated IL-15 mRNA isoform has a shorter open reading frame (ORF) due to stop codons in exon A, followed by a new AUG codon. The predicted IL-15 precursor protein displays a shorter signal peptide but shares the same aminoacidic composition of mature IL-15 protein. A possible functional role of IL-15, different from 'IL-2-like' activity, in human tumours, is suggested.

Alternative Splicing↗
PubMed1996

The natural killer-related receptor for HLA-C expressed on T cells from CD3+ lymphoproliferative disease of granular lymphocytes displays either inhibitory or stimulatory function.

Four patients with lymphoproliferative disease of granular lymphocytes (LDGL) coexpressing CD3 and the natural killer (NK)-related "p58" receptor for HLA-C alleles were studied. These CD3+p58+ LDGLs have been detected among a series of 44 CD3+ LDGLs analyzed. Two patients with LDGL (GI and BA) expressed only the p58 molecule defined by the GL-183 and CH-L monoclonal antibodies (MoAbs), while the cases of patients PU and MA also coexpressed the molecular form identified by EB6 anti-p58 MoAb. Three LDGL cases (GI, MA, and PU) displayed the CD8+4-CD16+ T-cell receptor (TCR)alpha/beta+ phenotype, while one patient (BA) was CD8+4+CD16+ TCRalpha/beta+. Freshly isolated granular lymphocytes (GL) from these cases displayed cytolytic activity in an anti-CD3 MoAb-triggered redirected killing assay against the Fcgamma-receptor+ (Fcgamma-R+) P815 target cell line. Lysis of P815 target cells, triggered by an anti-CD3 or by anti-CD16 MoAb, could be inhibited by the addition of anti-p58 MoAb in three fresh or interleukin (IL)-2-cultured GL tested (GI, MA, and PU). Triggering of cytotoxicity against the HLA-DR+ Fcgamma-R+ Daudi cell line induced by appropriate superantigens could also be inhibited by anti-p58 MoAb in patients PU and GI with LDGL. These data indicate that activation through the CD16, CD3, and TCR molecules can be modulated by p58 receptors in these LDGLs. On the contrary, IL-2-expanded cells of patient BA were induced to lyse P815 target cells by anti-p58 MoAb. In addition, anti-p58 MoAB enhanced anti-CD16 MoAb triggered lysis and did not inhibit activation via CD3. These data indicate that, in this particular patient with LDGL, p58 displays a stimulatory effect on cell triggering, rather than the typical inhibitory effect previously observed in p58+ T-cell clones derived from healthy donors. The anti-p58 MoAb did not induce CA++ mobilization in p58+ LDGLs and in a p58+CD3+ normal T-cell clone equipped with inhibitory p58 molecules, while Ca++ mobilization could be observed in cultured GL from patient BA, which could be activated by anti-58 MoAb. These findings suggest that stimulatory and inhibitory p58 molecules are equipped with different signal transducing properties, thus contributing to a better knowledge of the normal counterpart.

Antibodies, Monoclonal↗
PubMed1996

Analysis of IL-2 receptor expression and of the biological effects of IL-2 gene transfection in small-cell lung cancer.

We have analysed the expression of interleukin-2 receptor (IL-2R) on a panel of small-cell lung cancer (SCLC) cell lines. None of the 11 SCLC cell lines studied expressed detectable surface IL-2R alpha or beta chains by indirect immunofluorescence. Reverse transcriptase-polymerase chain reaction (RT-PCR) analyses indicated that only one out of 11 cell lines expressed detectable IL-2R beta mRNA while two expressed a weak positivity for IL-2R gamma. Five SCLC cell lines were transfected with the plasmid vector RSV.5 neo containing IL-2 cDNA coding sequence. Stable transfectants secreted biologically active IL-2 (ranging from 25 to 100 U ml-1 in the culture supernatant). IL-2 transfection did not produce significant modifications in the expression of surface molecules such as IL-2R alpha and beta chains, intercellular adhesion molecule-1 (ICAM-1), CD44, HLA class I and II or in IL-2R beta or gamma mRNA. More importantly, IL-2-transfected N592 and NCI H69 cell lines completely lost their tumorigenic potential in nude mice after subcutaneous injection, whereas experimental controls transfected with RSV.5 neo vector only, displayed an in vivo growth pattern identical to that of untransfected cells. In addition, in the N592 model, IL-2-producing N592 inhibited the growth of wild-type N592 injected at the same site, while injection of parental cells on the opposite side did not significantly affect the growth of wild-type tumour cells. Histopathological analysis of the rejection process of IL-2-transfected cells demonstrated the presence of MAC-1+, MAC-3+ macrophages and of RB68C5+ granulocytes, whereas T cells were undetectable and NK cells were scarcely represented. In addition, a reduction of the tumour blood vessels was observed. The possible relevance of these data for the development of vaccination strategies using cytokine-engineered tumour cells in SCLC is discussed.

Animals↗
PubMed1995

Anti-tumor efficacy of an anti-epidermal-growth-factor-receptor monoclonal antibody and its F(ab')2 fragment against high- and low-EGFR-expressing carcinomas in nude mice.

Monoclonal antibody (MAb) MINT5 specifically detects the epidermal-growth-factor receptor (EGFR). In vitro analyses of intact MINT5 (IgG1) and its F(ab')2 fragment indicated that both forms of the MAb inhibited binding of 125I-mEGF to EGFR, induced receptor internalization and blocked EGF-induced EGFR tyrosine-kinase activation in A431 cells. Both forms of the MAb also inhibited to the same extent the proliferation of the carcinoma cell lines A431 and IGROVI, despite the difference in EGFR levels on the cells. The detection of TGF alpha mRNA and the inhibition of cell growth in EGF-free conditions by anti-EGFR MAb indicated the involvement of an EGFR/TGF alpha autocrine/paracrine pathway in the in vitro growth of both cell lines. Analysis of mice xenotransplanted s.c. with A431 cells and treated with MINT5 revealed a block in A431 tumor take in 6 of 10 animals when intact MAb was administered from day 0 to day 11. On a molar basis, F(ab')2 at the same dose was ineffective, although at a 7-fold higher dose F(ab')2 reduced s.c. tumor growth by 80%. At the same dose, intact MINT5 MAb reduced s.c. growth of the EGFR-negative MeWo cell line by 5%. Survival of mice bearing IGROVI i.p. xenotransplants and treated locally with either form of MAb was significantly prolonged even when treatment was initiated on day 3. Corrected doses of intact and F(ab')2 fragment, which accounted for the difference in serum half-lives of the MAb forms, resulted in similar survival rates in the tumor-bearing mice. These pre-clinical results suggest that MINT5 MAb might be safely used for systemic therapy of EGFR-over-expressing tumors. Loco-regional therapy might be contemplated in the case of tumors with moderate/low EGFR expression.

Animals↗
PubMed1995

Expression of HOXC4 homeoprotein in the nucleus of activated human lymphocytes.

We have analyzed the expression of homeoproteins of the HOX family in resting and activated lymphoid cells and in neoplastic lymphoid cell lines by the use of monoclonal antibodies (MoAbs) already shown to react with the homeoproteins HOXA10, HOXC6, and HOXD4, respectively. Anti-HOXA10 and C6 MoAbs DIDi not show any reactivity with the lymphoid cells tested, whereas anti-HOXD4 MoAb stained few resting peripheral blood lymphocytes (PBLs) and most phytohemagglutinin (PHA)-stimulated PBLs as early as 6 hours after stimulation. The pattern of staining of PHA-activated PBLs is reminiscent of the stages of nucleolar fragmentation in different phases of the cell cycle. The MoAb reacted also with activated or Epstein-Barr virus-transformed B cells, with clonal or polyclonal T and natural killer (NK) cells, with leukemic T-cell lines, and with a Burkitt's lymphoma cell line. RNAse protection experiments, per formed with probes specific for HOXD4 or for the highly homologous HOXA4, HOXB4, and HOXC4, belonging to the same paralogy group, indicated that only HOXC4 mRNA is present in resting or activated PBLs. Northern blot analysis on polyA+ RNA from activated PBLs or Raji cells showed the presence of two different HOXC4 transcripts of 2.8 and 1.9 kb. Gel retardation and Southwestern blot assays showed the presence of a 32-kD homeoprotein with DNA-binding properties typical of a HOX4 homeoprotein in nucleolar extracts of PHA-activated, but not of resting, lymphocytes. Taken together, these data indicate that the HOXC4 homeoprotein is expressed in activated and/or proliferating lymphocytes of the T-, B-, or NK-cell lineage, whereas it is weakly expressed in a minority of resting cells. The early expression and the nucleolar localization suggest an involvement of HOXC4 in the regulation of genes controlling lymphocyte activation and/or proliferation.

Antibodies, Monoclonal↗
PubMed1995

Low doses of rIL2 after autologous bone marrow transplantation induce a "prolonged" immunostimulation of NK compartment in high-grade non-Hodgkin's lymphomas.

Ten patients with high-grade non-Hodgkin's lymphoma (HG-NHL) entered a subcutaneous (s.c.) recombinant interleukin 2 (rIL2) trial within 2 months of undergoing autologous bone marrow transplantation (ABMT). Immunological studies, consisting in T- and natural killer (NK)-cell subset assessment, together with functional assays, such as NK activity and CD16-mediated redirected killing assay, were performed before therapy, after 2 weeks, and then monthly. Phenotypic analysis showed a significant increase (p = 0.01) of CD16 and CD56 NK cells, from 12% to 28% and from 17% to 37%, respectively. In particular, the CD56bright NK cell population showed a tenfold increase, while CD56dim NK cells remained unmodified compared with pretreatment values. The expression of IL2 receptors was also studied and a significant increase (p = 0.01) of CD122 (p75)-positive cells from 8% to 30% was found, while no significant increase was observed in CD25 (p55)-positive cells. Furthermore, rIL2 administration led to an increase of NK activity even at the lowest effectors:target ratio and to an increase of CD16-mediated redirected killing assay. These phenotypic and functional modifications lasted throughout the duration of rIL2 therapy and remained after completion of therapy. In addition, none of the ten patients relapsed, and two of them who started IL2 treatment while still showing residual disease experienced a complete disappearance of the disease after 10 and 7 months of therapy, respectively. Our data suggest that infusion of rIL2 s.c. after ABMT is safe, can selectively increase NK cell number and function, and may have a beneficial effect on the minimal residual disease.

Adult↗
PubMed1995

In vitro and in vivo stability and anti-tumour efficacy of an anti-EGFR/anti-CD3 F(ab')2 bispecific monoclonal antibody.

The in vitro and in vivo stability and anti-tumour efficacy of the anti-EGFR/anti-CD3 bispecific monoclonal antibody (biMAb), M26.1, were analysed. The interaction of the intact biMAb with Fc receptor I (Fc gamma RI) present on human leucocytes was not observed when the antibody was used as an F(ab')2 fragment. A CD8+ T-cell clone coated with M26.1 F(ab')2 was as effective as the intact biMAb in inducing IGROV1 target cell lysis when tested in a 51Cr-release assay. Variable levels of reduction of F(ab')2 to monovalent F(ab') were observed upon incubation with human ovarian cancer ascitic fluid (OCAF) or with human glioblastoma cavity fluid (GCF), but not with mouse or human sera. Activated lymphocytes coated with F(ab')2 and incubated in vitro with GCF or OCAF for 24 and 48 h respectively maintained their targeting. Thus, the F(ab')2, when present as a soluble molecule, but not when bound to T cells, might lose some functional activity as a consequence of partial reduction to F(ab'). In normal mice, M26.1 F(ab')2 retained full cytotoxic activity in the circulation, and clearance values were similar to those obtained with parental and other MAb F(ab')2. Treatment of IGROV1 tumour-bearing mice with activated human lymphocytes coated with the M26.1 F(ab')2 significantly prolonged survival of the animals compared with tumour-bearing untreated and control mice treated with lymphocytes or F(ab')2 alone. Together, these results suggest the clinical usefulness of bispecific M26.1 F(ab')2 as a targeting agent for local treatment of tumours such as glioma and ovarian cancers that express variable levels of epidermal growth factor receptor (EGFR).

Animals↗
PubMed1995

Targeting of type 1 ribosome-inactivating proteins to CD30+ or CD25+ hematologic neoplasias by bispecific antibodies.

In this study, we compared the ability of different bispecific monoclonal antibodies (BsmAb) and immunotoxins to deliver the type 1 ribosome-inactivating proteins (RIP) saporin and gelonin through the CD25 or CD30 target molecules to Hodgkin's lymphoma cells. An anti-CD25/antisaporin and an anti-CD30/antisaporin BsmAb enhanced the toxicity of the relevant RIP against the CD25+CD30+ L540 Hodgkin's lymphoma cell line, although targeting by anti-CD30 BsmAb appeared eight times more efficient. Two anti-CD30/antigelonin BsmAb, reacting with different epitopes of the gelonin molecule, were able to enhance gelonin toxicity against L540 cells and had a synergistic effect when used in combination. Among CD25-CD30+ Hodgkin's lymphoma lines, which were resistant to targeting by anti-CD25/saporin BsmAb, one (L428) was sensitive to both gelonin and saporin delivered by anti-CD30 BsmAb. Another CD25-CD30+ cell line (COLE) was completely resistant to the toxic effect of gelonin targeted by the two synergistic BsmAb, as well as to an anti-CD30/gelonin immunotoxin. However, these cells were partially sensitive to saporin delivered by an anti-CD30/anti-saporin BsmAb, and they were efficiently killed by an anti-CD30/saporin immunotoxin. These results indicate that heterogeneity in the sensitivity to certain RIP, such as gelonin, exists among tumor cells of the same histotype.

Animals↗
PubMed1995

Cytolytic T lymphocytes displaying natural killer (NK)-like activity: expression of NK-related functional receptors for HLA class I molecules (p58 and CD94) and inhibitory effect on the TCR-mediated target cell lysis or lymphokine production.

Natural killer (NK) cells express surface receptors for defined groups of HLA class I alleles. The specific interaction between these receptors and HLA class I molecules expressed on target cells results in inhibition of NK-mediated target cell lysis. In this report, we analyzed whether similar mechanisms were operating in cytolytic T lymphocytes (CTLs) capable of lysing NK-sensitive target cells. T cell clones were screened for their ability to lyse K562 target cells. The selected clones expressed either gamma delta or alpha beta TCR. The majority of these clones failed to lyse the HLA class I+ R8/15375 cell line; however, upon addition of the previously described A6-136 (IgM) or 6A4 F(ab')2 anti-HLA class I mAbs, target cells were efficiently lysed. Lysis of autologous phytohemagglutinin blasts in the presence of anti-HLA class I mAbs occurred primarily with TCR gamma delta+ CTLs. Recognition of HLA class I molecules on target cells implies the expression of NK-related specific receptors in CTL clones. Indeed, phenotypic analysis of > 300 CTL clones with NK-like activity revealed that 28% expressed p58 molecules (specific for HLA-C alleles) while 30% expressed CD94 molecules (specific for the Bw6 specificity). These receptor molecules were found to function as inhibitory receptors, as revealed by the effect of anti-p58 or anti-CD94 mAbs (of IgG isotype) on the lysis of the Fc gamma R+ K562 target cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, CD↗
PubMed1995

Differential sensitivity of CD30+ neoplastic cells to gelonin delivered by anti-CD30/anti-gelonin bispecific antibodies.

Lymphocyte activation antigens, such as CD30, represent suitable target molecules for antibody-driven drug delivery in haemopoietic malignancies. A ribosome-inactivating protein (RIP) type 1 of potential interest for mAb targeting is gelonin, which displays a lower toxicity, as compared to other RIPs. In this study, two anti-CD30/antigelonin bispecific monoclonal antibodies (bimAbs), secreted by hybrid hybridomas, were used to deliver this RIP to CD30+ tumour cells. The two bimAbs, termed D4 and A18, were produced using the same anti-CD30 mAb and two anti-gelonin mAbs, directed to unrelated epitopes of the gelonin molecule. These bimAbs enhanced gelonin toxicity (IC50 5 x 10(-8) M, in the absence of mAbs) against the CD30+ L540 Hodgkin's lymphoma cell line in a protein synthesis inhibition assay. Thus, in the presence of 10(-9) M D4 bimAb, protein synthesis was inhibited with an IC50 of 5 x 10(-10) M as gelonin, whereas with A18 bimAb the IC50 was 8 x 10(-11) M. More interestingly, the combined use of the two bimAbs had a synergistic effect, since the IC50 of gelonin reached 6 x 10(-12) M. Among CD30 tumour cell lines, the Hodgkin's lymphoma L428 was also sensitive to gelonin delivered by bimAbs (IC50 6 x 10(-11) M), whereas the COLE Hodgkin's cell line and the T-ALL Jurkat were completely resistant to the toxic effect of gelonin and bimAbs. COLE and Jurkat cells were also resistant to a gelonin/anti-CD30 conventional immunotoxin, whereas they were sensitive to a saporin/anti-CD30 immunotoxin. This suggests that the resistance to gelonin is not related to a lack of internalization through the CD30 molecule but is associated with some property of the RIP.

Antibodies, Bispecific↗
PubMed1995

Nucleolar localisation of three Hox homeoproteins.

Homeoproteins encoded by genes of the Hox family are nuclear proteins believed to act as transcription factors and to participate in the determination of the body plan. Here we show that in several vertebrate cells, they exhibit a subnuclear localisation associated with the nucleolus. We used monoclonal antibodies to study the distribution of three homeoproteins, namely HOXB7, HOXC6 and HOXD4. The immunoreactivity to antibodies against HOXC6 protein in Xenopus laevis embryonic tissues is restricted to one or two spots within the nucleus; this distribution partially overlaps that of fibrillarin, a protein of the fibrillar zone of the nucleoli. Indirect immunofluorescence analysis of the distribution of HOXB7 protein in 3T3 cells, and of HOXD4 protein in human neuroblastoma and Raji lymphoma cell lines and activated lymphocytes, results invariably in a nucleolar localisation. Purified nucleoli from stimulated T lymphocytes, and Raji cells contain an activity capable of binding, in a gel retardation assay, to an oligonucleotide specifically recognised by the HOXD4 homeoprotein. This activity is specifically removed by anti-HOXD4 antibodies and is found associated in southwestern blots with a single band with an apparent M(r) of 30,000, corresponding to that of recombinant HOXD4. The functional significance of the nucleolar localisation of Hox proteins remains to be determined.

Animals↗
PubMed1994

The LFA-1/ICAM cell adhesion pathway is involved in tumor-cell lysis mediated by bispecific monoclonal-antibody-targeted T lymphocytes.

We investigated the role of the LFA-1/ICAM, VLA-4/VCAM-1 and CD2/LFA-3 adhesion pathways in the cytolysis of tumor cells mediated by an anti-EGF-R/anti-CD3 bispecific monoclonal antibody (biMAb). The biMAb induced efficient lysis of EGF-R+ tumor cells (A431, HT-29, IGROV-1 and MDA-MB468) by cytotoxic T lymphocytes (CTL) cultured in IL-2. Pretreatment of effector cells by anti-LFA-1 alpha (CD11a) and anti-LFA-1 beta (CD18) MAbs significantly inhibited cytolysis of all types of EGF-R+ tumor cells, while anti-CD2 and anti-VLA-4 MAbs were virtually ineffective. We investigated the expression of adhesion-molecule counter-receptors on tumor target cells by indirect immunofluorescence. HT-29, A431 and MDA-MB 468 tumor cells expressed an ICAM-1+2-3- VCAM-1- LFA-3+ phenotype, while IGROV-1 was ICAM-1-2+3- VCAM-1- LFA-3+. Pre-treatment of A431, HT-29 and MDA-MB468 with anti-ICAM-1 MAb inhibited cytolysis, further supporting the functional involvement of the LFA-1/ICAM adhesion pathway in biMAb-targeted tumor-cell lysis. In addition, treatment of target cells with TNF alpha or IFN gamma for 24 hr increased the expression of ICAM-1 in HT-29, A431 and MDA-MB468 (ICAM-2 was induced on IGROV-1) and also enhanced the sensitivity of these target cells to biMAb-targeted cytotoxicity. These data suggest that up-regulation of ICAM-molecule expression by inflammatory cytokines may increase susceptibility of tumor cells to biMAb-targeted lysis. Anti-LFA-1 MAbs did not significantly inhibit the formation of conjugates between biMAb-coated T lymphocytes and tumor cells. Co-aggregation of LFA-1 molecules with biMAb-bound CD3 molecules resulted in a more sustained and prolonged increase in the intracellular concentration of free Ca++ in CD8+ cultured CTL lines. These findings indicate that in T cells targeted by anti-CD3/anti-TAA biMAb LFA-1 may act as a co-receptor molecule which enhances signal transduction through the CD3/TCR complex.

Antibodies, Bispecific↗
PubMed1994

Biologic and clinical effects of continuous infusion interleukin-2 in patients with non-small cell lung cancer.

BACKGROUND: Interleukin-2 (IL-2) has shown antitumor activity in some neoplasms, such as melanoma and renal carcinoma, but toxicity derived from bolus administration is significant, particularly at the cardiorespiratory level. METHODS: To test feasibility, antitumor activity, pulmonary and systemic immunologic effects, and pulmonary function changes of continuous-infusion recombinant IL-2 given to patients with non-small cell lung cancer, eleven subjects with Stage III-IV disease were treated in a standard pulmonary medicine unit with a dose of 18 million IU/m2/day from day 1 to day 13 with 1-day rest on day 7. A second induction course was given after a 3-week rest. In patients with nonprogressive disease, four maintenance courses of 6 days' duration at the same dose were planned. Immunologic tests, including lymphocyte phenotype analysis and assays for the detection of tumor necrosis factor (TNF) and of anti-IL-2 antibodies, were performed before and after treatment in serum and bronchoalveolar lavage fluid (BAL). Cardiopulmonary function tests, including spirometry, arterial blood gas analysis, diffusion capacity, and echocardiography, were obtained before, during, and after treatment. RESULTS: Twenty-one cycles (15 induction courses plus 6 maintenance courses) were administered. No patient was able to complete the six planned courses, and only 3 patients entered the maintenance phase. Reasons for discontinuation included progressive disease in five cases, toxicity in three cases, and patient request in three cases. The most common side effects were fever, hypotension, oliguria, and elevated serum creatinine and liver enzyme levels. No patient required intubation or intensive care. No objective response was seen, and the median survival time was 10 months. Lymphocytosis and eosinophilia were observed in all patients. Surface marker analysis revealed a statistically significant increase in the percentage of CD3+, CD4+, CD25+ and DR+ cells in peripheral blood. Lymphoid cells derived from BAL disclosed an increased natural killer activity after IL-2 treatment, and TNF was increased in BAL fluid. Pulmonary function tests evidenced an increased alveolar-arterial difference for oxygen allied with a decrease of forced expiratory volume in 1 second, forced vital capacity, and carbon monoxide transfer coefficient consistent with a significant, albeit not clinically relevant, interstitial lung defect. CONCLUSION: Continuous-infusion IL-2 is feasible in patients with advanced lung cancer even outside an intensive care unit, but overall compliance is poor. Although clinical pulmonary toxicity is negligible, small but statistically significant alterations of the pulmonary function are evident. In addition, this regimen produces a significant activation of the immune system at the pulmonary level.

Antibodies↗
PubMed1994

T cell clones expressing the natural killer cell-related p58 receptor molecule display heterogeneity in phenotypic properties and p58 function.

A new anti-p58 monoclonal antibody (mAb), termed CH-L, has been used to characterize a minor subset of T lymphocytes co-expressing p58 and CD3 molecules. In two-color immunofluorescence analysis, CH-L+CD3+ cells represented 0.5 to 6% of the peripheral blood lymphocytes (in 20 healthy donors). Clonal analysis showed that most CD3+CH-L+ T cell clones expressed the CD8+4- T cell receptor (TcR) alpha/beta+ phenotype, while only a few were CD8-4+ TcR alpha/beta, CD8-4- TcR alpha/beta+ or CD8-4- TcR gamma/delta+. Western blot analysis indicated that the CH-L mAb identifies the same 56-58-kDa diffuse band in both T and natural killer cell (NK) clones. A minority of T cell clones also expressed other NK-related markers such as CD16, CD56 and CD94 and two clones also reacted with the anti-p58 mAb EB6. Interestingly, most clones displayed cytolytic activity in an anti-CD3 mAb-triggered redirected killing assay against the Fc gamma receptor+ P815 target cells and NK-like activity against K562 and Raji cells. In contrast, the IGROV-1 ovarian carcinoma cell line was resistant to cytolysis by all of these clones. Since p58 molecules have previously been shown to exert regulatory functions on NK-mediated lysis, we investigated whether anti-p58 mAb could also influence cytotoxicity mediated by CD3+p58+ T lymphocytes. Lysis of P815 target cells, triggered by anti-CD3 mAb, could be inhibited by anti-p58 mAb in 8 out of 12 cytolytic clones tested, while 4 clones were not inhibited. In addition, anti-p58 mAb enhanced the cytolytic activity of 3 clones against IGROV-1 and of 4 other clones against Raji target cells. Taken together, these data indicate that p58+ T cells express heterogeneous phenotypes and different forms of TcR and, in most instances, display cytolytic functions. Perhaps more importantly, the p58 molecule appears to modulate the cytolytic activity triggered via the CD3/TcR complex.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1994

Phenotypic, functional and molecular analysis of CD3- LGL expansions indicates a relationship to two different CD3- normal counterparts.

In this study we have analysed the CD3 and TCR transcript expression in three CD3- large granular lymphocyte (LGL) expansions. These LGL populations show a heterogenous attern of expression for CD2, CD8, CD16, CD56 and CD57 antigens. LGL1 is CD2+CD8-CD16+CD56+CD57+, while LGL2 is CD2-CD8+CD16-CD56-CD57-; LGL3 is similar to LGL1, except for CD8 antigen expression. Functional analysis has revealed a different behaviour of these LGL expansions in a cytotoxicity assay against the NK-sensitive K562 cell line. LGL1 and 3 display a significant NK-like activity, while LGL2 is inefficient against K562 target cells. TCR and CD3 transcript characterization of LGL expansions 1 and 3 showed that they expressed multiple TCR delta transcripts, a non-functional TCR beta transcript, CD3-zeta and -epsilon mRNA, but they lacked CD3 delta transcript and they lacked or expressed at very low levels of CD3 gamma transcript. On the other hand, LGL2 expressed TCR delta, CD3-gamma, -epsilon and -zeta transcripts, while it lacked CD3 delta mRNA. On the basis of these data, LGL1 and 3 seem to be closely related to peripheral blood mature natural killer (NK) cells, whereas LGL2 displays a pattern of TCR and CD3 expression similar to that found in CD1-2-3-4-8-16-thymocytes.

Adult↗