1. Activation of human T cells by a tumor vaccine infected with recombinant Newcastle disease virus producing IL-2
Markus Janke, Ben Peeters, Heng Zhao, Olav de Leeuw, Rob Moorman, Annette Arnold, Yvonne Ziouta, Philippe Fournier, Volker Schirrmacher Int J Oncol. 2008 Oct;33(4):823-32.
A new recombinant (rec) Newcastle disease virus (NDV) with incorporated human interleukin 2 (IL-2) as foreign therapeutic gene [rec(IL-2)] will be described. The foreign gene in rec(IL-2) did not affect the main features of NDV replication nor its tumor selectivity. Biologically active IL-2 was produced in high amounts by tumor cells infected with rec(IL-2). Tumor vaccine cells infected by rec(IL-2) stimulated human T cells to exert anti-tumor activity in vitro in a tumor neutralization assay. These effects were significantly increased when compared to vaccine infected by rec(-) virus without IL-2 gene. After incubation with rec(IL-2) infected tumor cells, T cells showed increased expression of the activation marker CD69 and produced increased amounts of IFNgamma when compared to T cells co-incubated with rec(-) infected tumor cells. CD8 T cells incubated with rec(IL-2) infected tumor cells showed upregulation of perforin, cell surface exposure of the degranulation marker CD107a and increased anti-tumor cytotoxic activity. Purified T cells from lymph nodes of head and neck squamous cell carcinoma (HNSCC) patients could be stimulated to secrete IFNgamma in an ELISPOT assay upon 40 h of stimulation with rec(IL-2) infected autologous tumor cells [ATV-rec(IL-2)] but not upon stimulation with rec(IL-2) infected allogeneic U937 tumor cells. This suggests direct activation of patient derived tumor antigen-specific memory T cells by ATV-rec(IL-2). In conclusion, the already inherent immunostimulatory properties of NDV could be further augmented by the introduction of the therapeutic gene IL-2. Active specific immunization of patients with ATV-rec(IL-2) should provide the microenvironment at the vaccination site with IL-2 and avoid side effects as seen after systemic IL-2 application.
2. Interleukin 2-like material in human epidermis: a ligand for the human interleukin 2-receptor 55 kD alpha chain
B Dreno, M M Hallet, J P Moisan, J P Soulillou, Y Jacques J Invest Dermatol. 1989 Jul;93(1):78-82. doi: 10.1111/1523-1747.ep12277358.
The antirecombinant interleukin 2 (rec-IL-2) monoclonal antibody (moAb) 15.2 cross-reacts with a skin antigen located at the cell surface of human keratinocytes within the granular layer. This study extends the analysis of this IL-2-like material to its reactivity with eight antibodies raised against natural IL-2, rec-IL-2 or IL-2 peptides. Four among them were found to react with the granular epidermal layer as well as with a simian virus 40 (SV40) transformed human keratinocyte cell line. Each of these four antibodies gave similar labeling patterns, although with different intensities, and competitively inhibited each other. Analysis at the messenger RNA level in epidermal cells and SVK 14 also indicated that this material is very likely different from IL-2. From the knowledge, for some of these antibodies, of the amino-acid regions they recognize on the IL-2 molecule, it is inferred that the skin antigen shares with IL-2 at least two overlapping epitopes located in the 33-54 amino-acid region of IL-2, a region that has been shown to be involved in the binding of IL-2 to the IL-2-receptor (IL-2-R) 55 kD chain. Indeed, a purified recombinant soluble species of this IL-2-R is shown in this study to bind specifically to the IL-2-like skin material. As far as IL-2-R bearing cells are found in normal epidermis (Langerhans cells) and as important infiltrates of IL-2-R positive T lymphocytes are often encountered in cutaneous diseases, a potential role for this IL-2-like material in skin immunophysiopathology is suggested.
3. NK-active cytokines IL-2, IL-12, and IL-15 selectively modulate specific protein kinase C (PKC) isoforms in primary human NK cells
Marco Vitale, Alessandra Bassini, Paola Secchiero, Prisco Mirandola, Cristina Ponti, Loris Zamai, Adriana R Mariani, Mirella Falconi, Giacomo Azzali Anat Rec. 2002 Feb 1;266(2):87-92. doi: 10.1002/ar.10039.
Natural killer (NK) cell function is largely modulated by growth factors and cytokines. In particular, interleukin (IL)-2, IL-12, and IL-15 have major effects on the proliferative and cytotoxic activities of NK cells against tumor and virus-infected cells. It is thought that the members of the protein kinase C (PKC) family of serine/threonine kinases play an important role in mediating the pleiotropic effects of cytokines on their target cells. We have investigated the downstream effects generated in purified human NK cells by IL-2, IL-12, and IL-15 on PKCalpha and PKCepsilon--a canonical and a novel isoform of PKC, respectively. By means of Western blotting, PKC activity assays, and immunofluorescence performed on highly purified preparations of primary human NK cells, we demonstrate that: 1) the three cytokines have similar effects on PKCalpha and PKCepsilon activities; 2) whereas PKCepsilon activity is induced by cytokine stimulation, PKCalpha activity is inhibited; and 3) both the induction of PKCepsilon and the inhibition of PKCalpha functional activity are relatively early events in NK cells, while longer cytokine stimulations do not generate significant variations in enzyme activity, suggesting that the activation of both the canonical and novel isoforms of PKC are events required in the early phases of cytokine-induced NK cell stimulation.
