Stanley Wolf | Washington University in St. Louis (original) (raw)

Papers by Stanley Wolf

European Journal of Immunology, 2001

Journal of Clinical Investigation, 1994

Interleukin 12 (IL-12), a heterodimeric cytokine composed of p40 and p35 chains, has potent immun... more Interleukin 12 (IL-12), a heterodimeric cytokine composed of p40 and p35 chains, has potent immunologic effects in vitro. We used tuberculous pleuritis as a model to study the immunoregulatory potential of IL-12 in vivo at the site of human infectious disease. Messenger RNAs for p40 and p35 were detected in pleural fluid from six of six patients by reverse-transcription polymerase chain reaction. By using an ELISA that detected both free p40 and heterodimeric IL-12, we found that mean concentrations were 585±89 pg/ml in pleural fluid of patients with tuberculous pleuritis, which were significantly higher than those in serum of the same patients (54±36 pg/ ml), or in malignant pleural effusions (123±35 pg/ml). By using an ELISA specific for heterodimeric IL-12, we found that mean concentrations in pleural fluid of patients with tuberculous pleuritis were 165±28 pg/ml and undetectable in serum of the same patients, or in malignant pleural effusions. Bioactive IL-12 was detectable in five of five supernatants of pleural fluid cells stimulated with Mycobacterium tuberculosis. Addition of anti-IL-12 antibodies suppressed proliferative responses of pleural fluid cells to M. tuberculosis by 36±7%. These data indicate that IL-12 may play a role in the human immune response to infectious agents in vivo. We hypothesize that IL-12 contributes to the antimycobacterial immune response by enhancing production of interferon-i, facilitating development of Thl cells and augmenting cytotoxicity of antigen-specific T cells and natural killer cells.

Cancer Research, 1994

Interleukin 12 (IL-12), a disulfide-linked heterodimeric cytokine produced primarily by macrophag... more Interleukin 12 (IL-12), a disulfide-linked heterodimeric cytokine produced primarily by macrophages, is composed of light (p35) and heavy (p40) chains. It binds to a receptor on T-ceils and natural killer cells, promoting the induction of primarily a Tid response in vitro and in vivo. To determine whether paracrine IL-12 secretion can alter tumor cell growth or promote antitumor immunity, we have developed a delivery system using genetically engineered fibroblasts in murine tumor models. NIH3T3 cells were stably transfected to express 100-240 units/106 cells/48 h of IL-12 using expression plasmids carrying both the murine p35 and p40 genes of murine IL-12. The effects of paracrine secretion of IL-12 on tumor establishment and vaccination models were examined using the poorly immunogenic murine melanoma cell line (BL-6) in C57BL/6 mice. To determine the effects of IL.12 on tumor formation, nonirradiated BL-6 cells were inoculated s.c. into C57BL/6 mice admixed with NIH3T3 cells transfected with both subunits of mIL-12 (3T3-IL-12) or with cells transfected with only the neomycin phosphotransferase gene (3T3-Neo). Compared to mice given injections of BL-6 alone, the day of emergence of detectable tumors was significantly delayed in mice given injections of BL-6 admixed with 3T3-IL-12, but not in mice with BL-6 admixed with 3T3-Neo. Effectiveness in this system was related to the amount of IL-12 expressed by the 3T3-IL-12. To determine the ability of locally secreted IL-12 at the tumor site to induce antitumor immunity, 106 irradiated tumor cells mixed with 3T3-IL-12 or 3T3-Neo were injected as a vaccine, and the response to a tumor challenge was subsequently examined. With a tumor challenge of less than 1 • los nonirradiated BL-6 cells, significant delay of establishment of tumor was noted with a relatively small amount of IL-12 secretion (1.2 units/5 • l0 s cells/48 h). Larger amounts of secreted IL-12 provided no additional therapeutic benefit. Histological examination of tumor inoculum with 3T3-IL-12 secreting a high level of IL-12 showed peritumoral accumulation of macrophages, a characteristic capsule around the tumor composed of palisades of fibroblasts, and decreased numbers of CD4+ cells in the tumor. These results suggest that local delivery of IL-12 inhibits tumor growth in a dose dependent manner but leads to the development of an antitumor immune response when IL-12 is expressed at the tumor site at the relatively small amount indicated above. These results suggest that IL-12, like IL-2,-4,-6, and-7 and granulocytemacrophage colony-stimulating factor, can induce an immune response against poorly immunogenic tumors.

Cancer Research, Oct 1, 1999

Fusion proteins consisting of the extracellular region of murine B7.1 or B7.2 and the Fc portion ... more Fusion proteins consisting of the extracellular region of murine B7.1 or B7.2 and the Fc portion of murine IgG2a (B7-IgG) were evaluated for their ability to promote antitumor responses. Therapeutic administration of soluble B7-IgG in mice with established tumors induced complete regression of the tumor and increased the survival of mice. In three models, MethA, P815, and MB49, mice with 7-day-old established tumors were cured with two to three treatment cycles of B7-IgG, given twice a week. Even in mice with an established B16/F10 tumor (a poorly immunogenic melanoma), therapeutic treatment with B7-IgG alone slowed tumor growth and increased survival significantly. Still stronger antitumor activity was achieved when B7-IgG was used as a vaccine adjuvant mixed with irradiated tumor cells. In 80% of mice with 7-day-old B16 tumors, tumors regressed completely, and mice survived for at least 80 days. In all tumor models, B7.1-IgG and B7.2-IgG had similar antitumor activity. B7-IgG-mediated tumor rejection was dependent on T cells, specifically CD8 cells, as demonstrated by the failure of B7-IgG to induce tumor regression in severe combined immunodeficient or CD8-depleted mice. In addition, mice that were cured of an established tumor were protected against a rechallenge with the same tumor for at least 4 months, suggesting the generation of memory responses. Surprisingly, the antitumor activity of B7-IgG was independent of IFN-␥, as demonstrated by tumor rejection in IFN-␥ knockout mice. Our findings demonstrate the potent capacity of B7-IgG to generate or enhance antitumor immune responses and suggest the clinical value of B7-IgG.

Journal of Immunological Methods, Jan 13, 2000

In this paper, we present a method for measuring antigen specific cytotoxic T lymphocyte CTL acti... more In this paper, we present a method for measuring antigen specific cytotoxic T lymphocyte CTL activity from individual mouse peripheral blood samples without animal sacrifice. Peripheral blood cells are stimulated in vitro with a cocktail of antigen, cytokines, costimulatory molecules and irradiated feeder cells resulting, 7 days later, in a readily detectable antigen specific signal from a well plated under limiting dilution conditions. This highly sensitive and antigen specific assay is more efficient than conventional CTL assays and thus increases the number of mice that can be tested in a single assay. Since blood samples can be assayed from an individual mouse at multiple times during the course of an in vivo study, the assay can facilitate and strengthen correlative studies on CTL responses and in vivo results.

Cancer Research, Oct 15, 2002

The therapeutic efficacy of combined antiangiogenic and immune therapy was tested against weakly ... more The therapeutic efficacy of combined antiangiogenic and immune therapy was tested against weakly immunogenic and highly metastatic 4T1 breast tumor using SU6668, an angiogenesis inhibitor and recombinant murine (rm) B7.2-IgG fusion protein, an immunostimulator. SU6668 inhibits the tyrosine kinase activity of three angiogenic receptors VEGFR2 (Flk-1/KDR), PDGFR␤, and FGFR1, which play a crucial role in tumorinduced vascularization. rmB7.2-IgG is a fusion protein of the extracellular domain of B7.2, and the hinge and constant domains of murine IgG2a. Intermolecule disulfide linkages are maintained so that it forms a dimer. Our studies showed that three weekly immunizations of BALB/c mice bearing 0.5-0.8 cm 4T1 breast tumors with rmB7.2-IgG and irradiated 4T1 tumor cells (B7.2-IgG/TC) resulted in a significant inhibition of tumor growth and formation of pulmonary metastases. T-cell depletion experiments revealed that both CD4 ؉ and CD8 ؉ T lymphocytes are required for stimulation of the antitumor and antimetastatic immune response by B7.2-IgG/TC. Treatment of mice with SU6668 substantially inhibited tumor vascularization but did not inhibit tumor infiltration by T lymphocytes or the T-cell response to rmB7.2-IgG therapy. On the contrary, tumors in mice immunized with B7.2-IgG/TC and treated with SU6668 had higher numbers of tumor infiltrating T cells than tumors of other groups. SU6668 treatments initiated either on day 3 or day 10 after inoculation of 4T1 tumor cells resulted in a significant inhibition of tumor growth. Similarly, three weekly immunizations with B7.2-IgG/TC starting either on day 7 or 12 inhibited growth of 4T1 tumors. However, the most potent antitumor effects were observed in mice treated with a combination of SU6668 and B7.2-IgG/TC. Analysis of pulmonary metastases revealed that combined therapy also had a more potent antimetastatic effect than each modality alone. These results indicate that antiangiogenic and immune therapies using SU6668 and B7.2-IgG/TC are compatible, and manifest complementary antitumor and antimetastatic effects. Combined antiangiogenic and immune therapy might represent a new strategy for cancer treatment.

Biochemistry Usa, 1977

... The dotted lines indicate the extrapolated shape of the peaks and the background used in dete... more ... The dotted lines indicate the extrapolated shape of the peaks and the background used in determining the counts in each species. Holler, 1967) and all the methyl groups are conserved during processing (Maden and Salim, 1974). ...

J Neuroimmunol, 2008

Cytosolic phospholipase A2 alpha (cPLA2 alpha) is the rate-limiting enzyme for release of arachid... more Cytosolic phospholipase A2 alpha (cPLA2 alpha) is the rate-limiting enzyme for release of arachidonic acid, which is converted primarily to prostaglandins via the cyclooxygenase (COX) 1/2 pathways, and leukotrienes via the 5-lipoxygenase (LO) pathway. We utilized inhibitors of cPLA2 alpha, COX-1/2 and 5-LO to determine the potential roles of these enzymes in development of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Blocking cPLA2 alpha prevented EAE development and greatly reduced antigen-induced production of Th1-type cytokines and IL-17. Blocking COX-1/2 delayed onset and reduced severity of EAE, and reduced production of Th1-type cytokines, but not IL-17. Blocking 5-LO delayed onset and reduced cumulative severity of EAE, but did not reduce production of Th1-type cytokines or IL-17. Finally, blockade of cPLA2 alpha from the onset of clinical EAE reduced duration of EAE relapses. Therefore, cPLA2 alpha represents a potential therapeutic target for treatment of MS.

Advances in Experimental Medicine and Biology, Feb 1, 1995

We have begun a series of experiments assessing the role of IL-12 in the humoral immune response.... more We have begun a series of experiments assessing the role of IL-12 in the humoral immune response. IL-12 is known to enhance cellular immunity causing a shift toward a Th1, as opposed to a Th2, response. IL-12 is also a potent stimulator of IFN-gamma production which, among other activities, modulates isotype expression particularly with respect to IgG2a. We have performed a series of experiments involving the concurrent dosing of mice with murine IL-12 and TNP-KLH followed by the monitoring of IgG1 and IgG2a anti-TNP responses and total IgG1 and IgG2a levels. Following administration of IL-12, specific anti-TNP titers showed an IgG2a increase while IgG1 responses were markedly lower than those exhibited by animals which did not receive IL-12. Total IgG1 levels in IL-12 treated mice remained at or near baseline while untreated mice demonstrated an increase in total IgG1 levels. In addition, lymph nodes from these mice were removed, stimulated with KLH and assayed for expression of murine IFN-gamma and IL-4. Murine IFN-gamma levels in supernatants obtained from IL-12 treated mice were elevated over those seen in untreated mice while IL-4 levels were suppressed.

Cancer research, 2001

With a slight asynchronous but consistent progression, all of the mammary glands of female BALB/c... more With a slight asynchronous but consistent progression, all of the mammary glands of female BALB/c mice transgenic for the transforming rat HER-2/neu oncogene progress to atypical hyperplasia and to invasive carcinoma. Previous studies have shown that chronic administration of interleukin (IL) 12 started at the 2nd week of age hampers this progression because of its ability to inhibit tumor angiogenesis and activate a nonspecific immune response. Here we show that a similar inhibition is achieved when 7-week-old mice with fully blown atypical hyperplasia receive a weekly injection of 100 ng IL-12 for 16 times. This lower-dose and later IL-12 administration induces high and sustained levels of serum IFN-gamma equivalent to those elicited by more frequent administrations. A lower-dose and less toxic treatment may thus be envisaged as a possible option in the management of preneoplastic mammary lesions.