Interleukin-12-induced cytotoxicity against syngeneic B cell lymphomas of SJL/J mice☆
Introduction
SJL/J mice exhibit a 90% incidence of B cell lymphomas (originally called reticulum cell sarcomas or RCS) at approximately 13 months of age. Since the first report by Murphy in 1963 [1], the results of studies by us and others (reviewed in [2]) have not only identified the phenotypic characteristics of these B cell lymphomas, but have also revealed a novel lymphomagenic mechanism, termed reverse immune surveillance [3], [4], [5]. This phenomenon refers to the inability of RCS cells to grow progressively in immunocompromised SJL recipients, and their dependence on tumor-activated Th2 cells to provide tumor growth-promoting cytokines, such as IL-4 and IL-5 [6], [7].
The discovery by Tsiagbe et al. [8], [9] that a unique superantigen (vSAg) encoded by an endogenous MMTV (Mtv-29) provirus in RCS tumor cells stimulated TCR Vβ16+ Th cells, offered a new perspective of the SJL/RCS lymphoma model. The results of these studies unequivocally demonstrated that the Mtv-29 provirus transcribes a vSAg, using the META promoter/enhancer [10], which is different from, and additional to, those produced by resting or LPS-activated, non-malignant SJL B cells. Moreover, by stimulating Vβ16+ T cells to produce the requisite tumor growth-promoting cytokines [9], this vSAg-29-induced host response represents a major contributing factor to the phenomenon of reverse immune surveillance.
In complementary studies, Lasky and co-workers [6], [11] showed that the cytokines that facilitated RCS tumor cell growth in vitro were those produced by Th2 cells (chiefly, IL-5). However, in addition to the Th2 cytokines that clearly supported RCS cell growth, numerous other cytokines, such as IL-2 and IFN-γ, were also present in the SN of cultures containing SJL lymphoid cells and syngeneic γ-RCS stimulator cells [12].
SJL mice exhibit a constitutively low natural killer (NK) phenotype [13], [14]. However, moderate to high levels of NK activity were seen in effector cells obtained from primary co-cultures of SJL lymphoid cells and γ-RCS stimulator cells [3], [15], as well as from lymphoid tissues of SJL mice injected with γ-RCS cells [15], and from tumor bearing SJL mice [15], [16]. Although these RCS-activated NK cells killed a variety of NK-susceptible tumor target cells (such as YAC-1 and RBL-3) no cytotoxicity was obtained when LAK-sensitive target cells (such as L1210) or syngeneic RCS lymphoma target cells were tested [15]. Therefore, the ability to stimulate NK activity in SJL mice appeared to be a unique property of RCS tumor cells, since similar cytotoxic effector function was not obtained following stimulation of SJL lymphoid cells with potent NK inducers, such as poly I:C and IFN-γ [14], [17].
Despite the stimulation of Th cells and NK cells, and the accompanying production of cytokines following exposure of naı̈ve SJL lymphoid cells to RCS tumor cells, development of tumor specific cytotoxic effector cells was not observed [18]. However, early transplantation studies [19], [20], using primary RCS lymphomas, suggested that tumor specific immunity could be generated against these lymphoma cells, although the basis for this immunity was not investigated. Moreover, following immunization of SJL mice with irradiated, long-term transplantable RCS cells, moderate levels of CTL-mediated, tumor-specific cytotoxic activity were obtained when RCS-primed lymphoid cells were restimulated in secondary co-cultures with γ-RCS cells [18].
In view of the involvement of Th subsets and distinct cytokines in humoral (Th2; IL-4, IL-5) and cell-mediated (Th1; IFN-γ, IL-12) immune responses [21], [22], we reasoned that the failure to develop tumor-specific CTL activity against RCS lymphomas following primary exposure might be due to an imbalance in the differentiation of Th cells, which favored Th2 over Th1 cells. Therefore, we reassessed the question of CTL development in the SJL/RCS lymphoma model, using IL-12 to modulate the response of SJL lymphoid cells to γ-RCS stimulator cells. These recent cytotoxicity experiments were facilitated by the development (in the years following the earlier CTL studies) of in vitro RCS cell lines for use as target cells in cytotoxicity assays [11], [23].
The results demonstrate that the presence of IL-12 during stimulation of naı̈ve SJL lymphoid cells with γ-RCS cells not only caused higher levels of NK activity, but the development of tumor-specific CTL also occurred. Moreover, while IFN-γ was necessary for the development of the observed CTL activity, without IL-12 it was insufficient, by itself, to trigger the generation of tumor-specific cytotoxic effector cells. Inclusion of IL-12 did not alter other quantitative parameters (e.g. proliferation or total number of “blast” cells) of the γ-RCS-induced response. Therefore, the qualitative changes that occurred in the presence of IL-12 most likely involved a switch from a predominantly Th2 to a Th1 response, resulting in production of tumor-specific cytotoxic effector cells. This conclusion was supported by the results of complementary in vitro experiments that showed an increase in the number of cells with intracytoplasmic IFN-γ in cultures containing IL-12 and a decrease in cells containing IL-4, and in vivo experiments that demonstrated reduced lymphoma cell growth in mice given γ-RCS/IL-12-induced effector cells prior to challenge with viable RCS cells. Overall, the results of our study indicate that IL-12 can modulate the RCS-induced response to favor the development of effector mechanisms that lead to tumor cell destruction.
Section snippets
Mice
SJL/J, BALB.B, C57BL/6J, C57L/J and CBA mice were purchased from the Jackson Laboratories (Bar Harbor, ME), and were housed in the AAALAC-accredited research animal facility (RAF) at the University of Medicine and Dentistry of New Jersey (Newark, NJ).
Antibodies and cytokines
Monoclonal antibodies (mAbs) were prepared as supernatants (SN) or as mouse ascites from hybridomas obtained from the American Type Culture Collection (ATCC, Rockville, MD) or colleagues, as indicated: 3.155 (recognizes all CD8 alleles), 83-12.5
Inclusion of IL-12 stimulates development of cytotoxic effector cells
Table 1 presents the results of a representative experiment that demonstrates the vigorous proliferative response of SJL lymphoid cells to syngeneic RCS lymphoma cells. This characteristic response has been well characterized by us and others [2], [3], and is primarily due to recognition of vSAg29 determinants on the RCS cells by TCR Vβ16+ cells within the responder population [8], [9]. As shown by the data in Table 1, the magnitude of this response is significantly higher than allostimulation
Discussion and conclusion
It is well documented that vSAg29 expressed by RCS cells stimulates primarily CD4+ Vβ16+ cells to produce tumor growth-promoting cytokines, such as IL-4 and IL-5 [6], [7]. It is thought that this form of host response, termed reverse immune surveillance [3], [4], [5], not only promotes the growth of transplantable tumor cell lines after adoptive transfer to young SJL recipients, but is also a central component in the etiology of these B cell lymphomas in aging SJL mice [2]. The observation of
Acknowledgements
The authors wish to thank Dr. Vincent Tsiagbe (New York University Medical Center, New York, NY) for help in performing the RNAse protection assay for cytokine gene expression and Dr. Roberto Chiarle (New York University Medical Center, New York, NY) for describing the histopathology of tissues obtained from tumor injected mice. We also wish thank Meg O’Donnell and the External Research Department of the Genetics Institute (Cambridge, MA) for providing the recombinant IL-12 for our studies, Dr.
References (60)
- et al.
Requirement for reverse immune surveillance for the growth of germinal center-derived murine lymphomas
Semin. Cancer Biol.
(2000) - et al.
Reverse immune surveillance: an adaptive mechanism used by tumor cells to facilitate their survival and growth
Semin. Cancer Biol.
(2000) - et al.
Natural killer cell activity in the reticulum cell sarcomas (RCS) of SJL/J mice
Cell Immunol.
(1979) - et al.
Properties of reticulum cell sarcomas in SJL/J mice. IV. Minimal development of cytotoxic cells despite marked proliferation to syngeneic RCS in vivo and in vitro
Cell Immunol.
(1977) - et al.
IL-10 production in a CD5+ B cell lymphoma arising in a CD4 monoclonal antibody-treated SJL mouse
Clin. Immunol. Immunopathol.
(1992) - et al.
T-helper-cell-specific monoclonal antibody inhibits growth of B-cell lymphomas in syngeneic SJL/J mice
Cell Immunol.
(1989) Interleukin-12: a cytokine produced by antigen-presenting cells with immunoregulatory functions in the generation of T-helper cells type 1 and cytotoxic lymphocytes
Blood
(1994)- et al.
B lymphoma cells of C57L mice; the role of natural killer cells and T helper cells in lymphoma development and growth
Leukemia Res.
(2000) - et al.
Interleukin-12-activated natural killer cells recognize B7 costimulatory molecules on tumor cells and autologous dendritic cells
Blood
(1998) - et al.
Changes in macrophages and their functions with aging in C57BL/6J, AKR/J, and SJL/J mice
Cell Immunol.
(1982)
SJL/J, a new inbred strain of mouse with a high, early incidence of reticulum-cell neoplasms
Proc. Am. Assoc. Cancer Res.
Dependence of lymphoma growth on reversed immunological surveillance
Pathol. Immunopathol. Res.
Characterization and growth factor requirements of SJL lymphomas. II. Interleukin 5 dependence of the in vitro cell line, cRCS-X, and influence of other cytokines
Eur. J. Immunol.
Superantigens related to B cell hyperplasia
Springer Semin. Immunopathol.
Linkage of superantigen-like stimulation of syngeneic T cells in a mouse model of follicular center B cell lymphoma to transcription of endogenous mammary tumor virus
EMBO J.
Syngeneic response to SJL follicular center B cell lymphoma (reticular cell sarcoma) cells is primarily in Vb16+ CD4+ T cells
J. Immunol.
Control of endogenous mouse mammary tumor virus superantigen expression in SJL lymphomas by a promoter within the environmental region
J. Immunol.
Characterization and growth factor requirements of SJL lymphomas. I. Development of a B cell growth factor-dependent in vitro cell line, cRCS-X
J. Immunol.
Natural killer cell activity in reticulum-cell sarcomas of SJL/J mice. II. Analysis of RCS-associated NK activity
Int. J. Cancer
Selective defect of natural killer and killer cell activity against lymphomas in SJL mice: low responsiveness to interferon inducers
J. Immunol.
Syngeneic B lymphoma cells provide a unique stimulus to natural killer (NK) cells in genetically low-NK SJL/J mice
J. Leukocyte Biol.
Natural killer cell activity in reticulum-cell sarcomas of SJL/J mice. III. Characterization of the effector cells within RCS that mediate NK lysis
Int. J. Cancer
Transplantation behavior of Hodgkin’s-like reticulum cell neoplasms of the strain SJL/J mice and results of tumor reinoculation
J. Natl. Cancer Inst.
Immunologic properties of reticulum cell sarcomas of SJL/J mice
J. Natl. Cancer Inst.
Functional diversity of T lymphocytes due to secretion of different cytokine patterns
FASEB J.
Induction of Th1 and Th2 CD4+ T cell responses
Ann. Rev. Immunol.
Natural killer cells in the mouse. I. Cytotoxic cells with specificity for mouse Moloney leukemia cells. Specificity and distribution according to geneotype
Eur. J. Immunol.
Low density of Th-1 antigen on mouse effector cells mediating natural cytotoxicity against tumor cells
J. Immunol.
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Some of the results presented in this manuscript were submitted in partial fulfilment of the requirements for award of a Ph.D. from the UMDNJ, Graduate School of Biomedical Sciences.
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Present address: Department of Opthalmology, The Emory Eye Centre, 1365 Clifton Road NE, Atlanta, GA 30322, USA.