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Zettl M, Wurm M, Schaaf O, Mostböck S, Tirapu I, Apfler I, Lorenz IC, Frego L, Kenny C, Thibodeau M, Oquendo Cifuentes E, Reschke M, Moll J, Kraut N, Vogt A, Sedgwick JD, Waizenegger IC. Combination of two novel blocking antibodies, anti-PD-1 antibody ezabenlimab (BI 754091) and anti-LAG-3 antibody BI 754111, leads to increased immune cell responses. Oncoimmunology 2022; 11:2080328. [PMID: 35756842 PMCID: PMC9225207 DOI: 10.1080/2162402x.2022.2080328] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
Upregulation of inhibitory receptors, such as lymphocyte activation gene-3 (LAG-3), may limit the antitumor activity of therapeutic antibodies targeting the programmed cell death protein-1 (PD-1) pathway. We describe the binding properties of ezabenlimab, an anti-human PD-1 antibody, and BI 754111, an anti-human LAG-3 antibody, and assess their activity alone and in combination. Ezabenlimab bound with high affinity to human PD-1 (KD = 6 nM) and blocked the interaction of PD-1 with PD-L1 and PD-L2. Ezabenlimab dose-dependently increased interferon-γ secretion in human T cells expressing PD-1 in co-culture with PD-L1-expressing dendritic cells. Administration of ezabenlimab to human PD-1 knock-in mice dose-dependently inhibited growth of MC38 tumors. To reduce immunogenicity, ezabenlimab was reformatted from a human IgG4 to a chimeric variant with a mouse IgG1 backbone (BI 905725) for further in vivo studies. Combining BI 905725 with anti-mouse LAG-3 antibodies improved antitumor activity versus BI 905725 monotherapy in the MC38 tumor model. We generated BI 754111, which bound with high affinity to human LAG-3 and prevented LAG-3 interaction with its ligand, major histocompatibility complex class II. In an in vitro model of antigen-experienced memory T cells expressing PD-1 and LAG-3, interferon-γ secretion increased by an average 1.8-fold versus isotype control (p = 0.027) with BI 754111 monotherapy, 6.9-fold (p < 0.0001) with ezabenlimab monotherapy and 13.2-fold (p < 0.0001) with BI 754111 plus ezabenlimab. Overall, ezabenlimab and BI 754111 bound to their respective targets with high affinity and prevented ligand binding. Combining ezabenlimab with BI 754111 enhanced in vitro activity versus monotherapy, supporting clinical investigation of this combination (NCT03156114; NCT03433898).
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Affiliation(s)
- Markus Zettl
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Melanie Wurm
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Otmar Schaaf
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Sven Mostböck
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Iñigo Tirapu
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Ilse Apfler
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Ivo C Lorenz
- Boehringer Ingelheim Pharmaceuticals, Inc, Ridgefield, CT, USA
| | - Lee Frego
- Boehringer Ingelheim Pharmaceuticals, Inc, Ridgefield, CT, USA
| | - Cynthia Kenny
- Boehringer Ingelheim Pharmaceuticals, Inc, Ridgefield, CT, USA
| | | | | | | | - Jürgen Moll
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Norbert Kraut
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Anne Vogt
- Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
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2
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Kunkl M, Amormino C, Caristi S, Tedeschi V, Fiorillo MT, Levy R, Popugailo A, Kaempfer R, Tuosto L. Binding of Staphylococcal Enterotoxin B (SEB) to B7 Receptors Triggers TCR- and CD28-Mediated Inflammatory Signals in the Absence of MHC Class II Molecules. Front Immunol 2021; 12:723689. [PMID: 34489975 PMCID: PMC8418141 DOI: 10.3389/fimmu.2021.723689] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 08/02/2021] [Indexed: 01/19/2023] Open
Abstract
The inflammatory activity of staphylococcal enterotoxin B (SEB) relies on its capacity to trigger polyclonal T-cell activation by binding both T-cell receptor (TCR) and costimulatory receptor CD28 on T cells and MHC class II and B7 molecules on antigen presenting cells (APC). Previous studies highlighted that SEB may bind TCR and CD28 molecules independently of MHC class II, yet the relative contribution of these interactions to the pro-inflammatory function of SEB remained unclear. Here, we show that binding to MHC class II is dispensable for the inflammatory activity of SEB, whereas binding to TCR, CD28 and B7 molecules is pivotal, in both human primary T cells and Jurkat T cell lines. In particular, our finding is that binding of SEB to B7 molecules suffices to trigger both TCR- and CD28-mediated inflammatory signalling. We also provide evidence that, by strengthening the interaction between CD28 and B7, SEB favours the recruitment of the TCR into the immunological synapse, thus inducing lethal inflammatory signalling.
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Affiliation(s)
- Martina Kunkl
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy.,Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
| | - Carola Amormino
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy.,Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
| | - Silvana Caristi
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy.,Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
| | - Valentina Tedeschi
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy
| | - Maria Teresa Fiorillo
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy
| | - Revital Levy
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Andrey Popugailo
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Raymond Kaempfer
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Loretta Tuosto
- Department of Biology and Biotechnology Charles Darwin, Sapienza University, Rome, Italy.,Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Sapienza University, Rome, Italy
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3
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Transcytosis, Antitumor Activity and Toxicity of Staphylococcal Enterotoxin C2 as an Oral Administration Protein Drug. Toxins (Basel) 2016; 8:toxins8060185. [PMID: 27322320 PMCID: PMC4926151 DOI: 10.3390/toxins8060185] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 06/06/2016] [Indexed: 11/17/2022] Open
Abstract
Staphylococcal enterotoxin C2 (SEC2) is a classical superantigen (SAg), which can tremendously activate T lymphocytes at very low dosage, thus exerting its powerful antitumor activity. As an intravenous protein drug and a bacterial toxin, SEC2 has some limitations including poor patient compliance and toxic side effects. In this research, we devoted our attention to studying the antitumor activity and toxicity of SEC2 as a potential oral administration protein drug. We proved that His-tagged SEC2 (SEC2-His) could undergo facilitated transcytosis on human colon adenocarcinoma (Caco-2) cells and SEC2-His was detected in the blood of rats after oral administration. Furthermore, oral SEC2-His caused massive cytokine release and immune cell enrichment around tumor tissue, leading to inhibition of tumor growth in vivo. Meanwhile, although SEC2-His was dosed up to 32 mg/kg in mice, no significant toxicity was observed. These data showed that SEC2 can cross the intestinal epithelium in an immunologically integral form, maintaining antitumor activity but with reduced systemic toxicity. Therefore, these results may have implications for developing SEC2 as an oral administration protein drug.
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4
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Akbari A, Mobini GR, Maghsoudi R, Akhtari J, Faghihloo E, Farahnejad Z. Modulation of transforming growth factor‑β signaling transducers in colon adenocarcinoma cells induced by staphylococcal enterotoxin B. Mol Med Rep 2015; 13:909-14. [PMID: 26647993 DOI: 10.3892/mmr.2015.4596] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 09/09/2015] [Indexed: 11/06/2022] Open
Abstract
Colorectal cancer (CRC) is a notable cause of cancer‑associated mortality worldwide, making it a pertinent topic for the study of cancer and its treatment. Staphylococcal enterotoxin B (SEB), an enterotoxin produced by Staphylococcus aureus, has been demonstrated to exert anticancer and antimetastatic effects due to its ability to modify cell immunity and cellular signaling pathways. In the current study, SEB was investigated, including whether it exerts its growth inhibitory effects on colon adenocarcinoma cells. This may occur through the manipulation of a key tumor growth factor, termed transforming growth factor‑β (TGF‑β), and its signaling pathway transducer, Smad2/3. The human colon adenocarcinoma HCT116 cell line was treated with different concentrations of SEB, and cell number was measured using MTT assay at different treatment times. Smad2/3 RNA expression level was analyzed in untreated or SEB‑treated cells using quantitative polymerase chain reaction, which indicated significant differences between cell viability and Smad2/3 expression levels. SEB effectively downregulated Smad2/3 expression in the HCT116 cells at concentrations of 1 and 2 µg/ml (P=0.0021 and P=0.0017, respectively). SEB concentrations that were effective at inhibiting Smad2/3 expression were correlated with those able to inhibit the proliferation of the cancer cells. SEB inhibited Smad2/3 expression at the mRNA level in a concentration‑ and time‑dependent manner. The present study thus proposed SEB as an agent able to significantly reduce Smad2/3 expression in colon cancer cells, provoking moderate TGF‑β growth signaling and the reduction of tumor cell proliferation.
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Affiliation(s)
- Abolfazl Akbari
- Colorectal Research Center, Iran University of Medical Sciences, Tehran 1313114456, Iran
| | - Gholam Reza Mobini
- Medical Plants Research Center, Shahrekord University of Medical Sciences, Shahrekord 8815713471, Iran
| | - Reza Maghsoudi
- Department of Microbiology and Immunology, Shahrekord University of Medical Sciences, Shahrekord 8815713471, Iran
| | - Javad Akhtari
- Immunogenetic Research Center, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari 48175866, Iran
| | - Ebrahim Faghihloo
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran 1313114456, Iran
| | - Zohreh Farahnejad
- Department of Medical Mycology, AJA University of Medical Sciences, Tehran 1917793164, Iran
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5
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Matsueda S, Shichijo S, Nagata S, Seki C, Yamada A, Noguchi M, Itoh K. Identification of novel Lck-derived T helper epitope long peptides applicable for HLA-A2(+) cancer patients as cancer vaccine. Cancer Sci 2015; 106:1493-8. [PMID: 26331453 PMCID: PMC4714684 DOI: 10.1111/cas.12805] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 08/20/2015] [Accepted: 08/27/2015] [Indexed: 01/04/2023] Open
Abstract
The present study attempted to identify T helper epitope long peptides capable of inducing cytotoxic T lymphocytes (CTL) from Lck antigen (p56(Lck) ), the src family tyrosine kinase, which is known to be aberrantly expressed in metastatic cancers cells, in order to develop a long peptide-based cancer vaccine for HLA-A2(+) cancer patients. Based on the biding motif to the HLA-DR and HLA-A2 alleles, 94 peptides were prepared from the Lck antigen. These peptides were screened for their reactivity to immunoglobulin G (IgG) from plasma of cancer patients, followed by testing of their ability to induce both CD4(+) and CD8(+) T lymphocytes showing not only peptide-specific IFN-γ production but cytotoxicity against HLA-A2(+) cancer cells from peripheral blood mononuclear cells (PBMC) of HLA-A2(+) cancer patients. Among 94 peptides tested, the three T helper epitope long peptides and their inner CTL epitope short peptides with HLA-A2 binding motifs were frequently recognized by IgG of cancer patients, and efficiently induced both CD4(+) IFN-γ(+) and CD8(+) IFN-γ(+) T lymphocytes. Patients' PBMC stimulated with these long peptides showed cytotoxicity against HLA-A2(+) Lck(+) cancer cells in HLA-class I and HLA-class II dependent manners. These three peptides might be useful for long peptide-based vaccines for HLA-A2(+) cancer patients with Lck(+) tumor cells.
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Affiliation(s)
| | | | - Sayaka Nagata
- Cancer Vaccine Center, Kurume University, Kurume, Japan
| | - Chieko Seki
- Cancer Vaccine Center, Kurume University, Kurume, Japan
| | - Akira Yamada
- Cancer Vaccine Development Division, Research Center for Innovative Cancer Therapy, Kurume University, Kurume, Japan
| | - Masanori Noguchi
- Cancer Vaccine Center, Kurume University, Kurume, Japan.,Clinical Research Division, Research Center for Innovative Cancer Therapy, Kurume University, Kurume, Japan
| | - Kyogo Itoh
- Cancer Vaccine Center, Kurume University, Kurume, Japan
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6
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Hammamieh R, Chakraborty N, Lin Y, Shupp JW, Miller SA, Morris S, Jett M. Characterization of the interaction of staphylococcal enterotoxin B with CD1d expressed in human renal proximal tubule epithelial cells. BMC Microbiol 2015; 15:12. [PMID: 25649790 PMCID: PMC4327782 DOI: 10.1186/s12866-015-0344-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 01/13/2015] [Indexed: 11/19/2022] Open
Abstract
Background Participation of renal cells in the pathogenesis of staphylococcal enterotoxin B (SEB) is critical for late cleansing and sequestration of the antigens facilitated by CD1d mediated antigen sensing and recognition. This is a noted deviation from the typical antigen recognition process that recruits the major histocompatibility complex class II (MHC II) molecules. The immunological importance of CD1d is underscored by its influences on the performances of natural killer T-cells and thereby mediates the innate and adaptive immune systems. Results Using diffraction-based dotReady™ immunoassays, the present study showed that SEB directly and specifically conjugated to CD1d. The specificity of the conjugation between SEB and CD1d expressed on human renal proximal tubule epithelial cells (RPTEC) was further established by selective inhibition of CD1d prior to its exposure to SEB. We found that SEB induced the expression of CD1d on the cell surface prompting a rapid conjugation between them. The mRNA transcripts encoding CD1d remained elevated potentially after completing the antigen cleansing process. Conclusion Molecular targets associated with the delayed pathogenic response have essential therapeutic values. Particularly in the event of bioterrorism, the caregivers are typically able to intervene much later than the toxic exposures. Given circumstances mandate a paradigm shift from the conventional therapeutic strategy that counts on targeting the host markers responding to the early assault of pathogens. We demonstrated the role of CD1d in the late stage of pathogen recognition and cleansing, and thereby underscored its clinical potential in treating bioweaponizable antigens, such as Staphylococcal enterotoxin B (SEB). Electronic supplementary material The online version of this article (doi:10.1186/s12866-015-0344-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rasha Hammamieh
- Integrative Systems Biology, US Army Center for Environmental Health Research Fort Detrick, 568 Doughten Drive, Fort Detrick, MD, 21702-5010, USA.
| | - Nabarun Chakraborty
- Integrative Systems Biology, US Army Center for Environmental Health Research Fort Detrick, 568 Doughten Drive, Fort Detrick, MD, 21702-5010, USA.
| | - Yixin Lin
- Axela, Inc., 50 Ronason Drive, Suite 105, Toronto, ON, M9W 1B3, Canada.
| | - Jeffrey W Shupp
- The Burn Center, Department of Surgery, Washington Hospital Center, Washington, DC, 20010, USA.
| | - Stacy-Ann Miller
- Integrative Systems Biology, US Army Center for Environmental Health Research Fort Detrick, 568 Doughten Drive, Fort Detrick, MD, 21702-5010, USA.
| | - Sam Morris
- Axela, Inc., 50 Ronason Drive, Suite 105, Toronto, ON, M9W 1B3, Canada.
| | - Marti Jett
- Integrative Systems Biology, US Army Center for Environmental Health Research Fort Detrick, 568 Doughten Drive, Fort Detrick, MD, 21702-5010, USA.
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7
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Assessment of the functional regions of the superantigen staphylococcal enterotoxin B. Toxins (Basel) 2013; 5:1859-71. [PMID: 24152989 PMCID: PMC3813916 DOI: 10.3390/toxins5101859] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 10/09/2013] [Accepted: 10/10/2013] [Indexed: 11/17/2022] Open
Abstract
The functional activity of superantigens is based on capacity of these microbial proteins to bind to both the β-chain of the T cell receptor (TcR) and the major histocompatibility complex (MHC) class II dimer. We have previously shown that a subset of the bacterial superantigens also binds to a membrane protein, designated p85, which is expressed by renal epithelial cells. This binding activity is a property of SEB, SEC1, 2 and 3, but not SEA, SED, SEE or TSST. The crystal structure of the tri-molecular complex of the superantigen staphylococcal enterotoxin B (SEB) with both the TcR and class II has previously been reported. However, the relative contributions of regions of the superantigen to the overall functional activity of this superantigen remain undefined. In an effort to better define the molecular basis for the interaction of SEB with the TcR β-chain, we report studies here which show the comparative contributions of amino- and carboxy-terminal regions in the superantigen activity of SEB. Recombinant fusion proteins composed of bacterial maltose-binding protein linked to either full-length or truncated toxins in which the 81 N-terminal, or 19 or 34 C-terminal amino acids were deleted, were generated for these studies. This approach provides a determination of the relative strength of the functional activity of the various regions of the superantigen protein.
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8
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Terman DS, Bohach G, Vandenesch F, Etienne J, Lina G, Sahn SA. Staphylococcal superantigens of the enterotoxin gene cluster (egc) for treatment of stage IIIb non-small cell lung cancer with pleural effusion. Clin Chest Med 2006; 27:321-34. [PMID: 16716821 DOI: 10.1016/j.ccm.2006.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
There has been renewed interest in the superantigens as antitumor agents with the discovery of a group of bacterial superantigens known as the enterotoxin gene cluster (egc staphylococcal enterotoxins [SEs]). This article discusses the mechanisms by which egc SEs induce tumor killing and pleurodesis. The application of SE homolog and nucleic acid compositions as vaccines and for treatment of established tumors is reviewed. Finally, the use of native SEs ex vivo-intratumorally and intravesicularly administered superantigens against established tumors-is described and the interrelation between superantigen therapy and chemoradiotherapy.
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9
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Ren S, Terman DS, Bohach G, Silvers A, Hansen C, Colt H, Sahn SA. Intrapleural Staphylococcal Superantigen Induces Resolution of Malignant Pleural Effusions and a Survival Benefit in Non-Small Cell Lung Cancer. Chest 2004; 126:1529-39. [PMID: 15539723 DOI: 10.1378/chest.126.5.1529] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Malignant pleural effusion (MPE) may occur in up to 50% of patients with non-small cell lung cancer (NSCLC). The majority of these patients have a poor performance status and a dismal prognosis, with survival duration ranging from 2 to 3 months. Since these patients are typically symptomatic from their MPE, prompt treatment is required. Patients with symptomatic MPE from NSCLC and poor performance scores (Eastern Cooperative Oncology Group [ECOG] score >/= 2, Karnofsky performance status [KPS] score < 50) are generally not offered systemic chemotherapy. Treatment is palliative and includes intrapleural catheter drainage or chemical pleurodesis with talc, doxycycline, or bleomycin. None of the latter modalities prolong survival. OBJECTIVE Our goal was to investigate the toxicity and therapeutic effect of a new therapeutic agent, Staphylococcus aureus superantigen (SSAg), a powerful T-cell stimulant administered intrapleurally to unselected, consecutive patients with MPE from NSCLC (stage IIIb with pleural effusion) and a poor performance status. By providing direct access of the SSAg to the bronchial and mediastinal lymphatics, we predicted that intrapleural administration of SSAg would induce resolution of MPE and prolong survival in this population with advanced NSCLC and a limited prognosis. METHODS Fourteen consecutive, unselected patients with MPE from NSCLC and a median pretreatment KPS score of 40 (range, 10 to 60) received pleural instillation of SSAg, 100 to 400 pg, once or twice weekly (mean, 3.7 +/- 1.3 treatments [+/- SD]) until the pleural effusions resolved. They were evaluated for drug toxicity, resolution, duration of MPE, and survival. RESULTS Other than mild fever (maximum grade 2), toxicity of SSAg treatment was trivial and notably devoid of respiratory distress or hypotension. Eleven patients had a complete response (CR), and 3 patients had a partial response of their MPE. In 12 patients, the response endured for > 90 days, with a median time to recurrence of 5 months (range, 3 to 23 months). The median survival for the SSAg-treated group was 7.9 months (range, 2 to 36 months; 95% confidence interval [CI], 5.9 to 11.4 months), compared to a median survival of 2.5 months (range, 0.1 to 57 months; 95% CI, 1.3 to 3.4 months) for 18 consecutive, unselected patients with MPE from NSCLC (stage IIIb) treated with talc poudrage (p = 0.044). Survival duration of all 14 SSAg-treated cases and 13 talc-poudrage-treated patients with comparable pretreatment KPS (range, 10 to 60; median, 40 and 30, respectively), and distribution (p = 0.5) was 7.9 months (95% CI, 5.9 to 11.4 months) and 2.0 months (95% CI, 0.4 to 2.9 months), respectively (p = 0.0023). Nine of 14 patients treated with SSAg survived > 6 months, 4 patients survived > 9 months, and 3 patients survived > 350 days. One of the patients in the CR group has survived 36 months. None of the 13 talc-treated patients survived > 6 months. INTERPRETATION In 14 unselected, consecutive patients with MPE from NSCLC and poor pretreatment performance (median KPS of 40), the intrapleural administration of SSAg was efficacious in resolving the MPE without any clinically important adverse effects. SSAg-treated patients with a median KPS of 40 (range, 10 to 60) had a median survival that exceeded that with talc poudrage, and was comparable to current systemic chemotherapy used in patients with KPS >/= 70 status. SSAg treatment is simple to perform, minimally invasive, and does not require hospital time. It may be an attractive alternative to existing palliative modalities for stage IIIb patients with MPE and poor performance who are not candidates for systemic chemotherapy.
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Affiliation(s)
- Shaohua Ren
- Division of Pulmonary & Critical Care Medicine, 96 Lucas St, Box 250630, Charleston, SC 29425, USA
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10
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Kuroishi T, Komine KI, Asai KI, Kobayashi J, Watanabe K, Yamaguchi T, Kamata SI, Kumagai K. Inflammatory responses of bovine polymorphonuclear neutrophils induced by staphylococcal enterotoxin C via stimulation of mononuclear cells. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2004; 10:1011-8. [PMID: 14607860 PMCID: PMC262437 DOI: 10.1128/cdli.10.6.1011-1018.2003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To elucidate the pathological roles of staphylococcal enterotoxin C (SEC) in bovine staphylococcal mastitis, a histopathological analysis of SEC-inoculated mammary glands was performed. SEC-inoculated mammary glands exhibited interstitial inflammation, and the leukocytes that migrated into the gland were predominantly polymorphonuclear neutrophils (PMN). In the gland cistern tissues dissected from SEC-inoculated mammary glands, epithelial cellular degeneration was observed. We also investigated the physiological effects of SEC on PMN in vitro. PMN migration was induced by culture supernatant of SEC-stimulated peripheral blood mononuclear cells (S-PBMC sup) but not by that of nonstimulated PBMC (N-PBMC sup). The concentration of interleukin-8 was significantly (P < 0.05) higher in S-PBMC sup than N-PBMC sup, and a significantly (P < 0.05) higher mRNA expression of growth-regulated oncogenes was detected in SEC-stimulated PBMC than in nonstimulated PBMC. Milk PMN collected from SEC-inoculated mammary glands produced more than 2 times the amount of superoxide at 1 day postinoculation (dpi) than at 0 dpi in the presence of phorbol 12-myristate 13-acetate (PMA). PMN cultured with S-PBMC sup for 24 h also produced significantly (P < 0.05) larger amounts of superoxide than those cultured with N-PBMC sup in the presence of PMA. Moreover, S-PBMC sup induced the long-time survival of PMN. These results indicate that SEC induces the activation of PMN via the stimulation of mononuclear cells.
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11
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Stohl W, Xu D, Zang S, Kim KS, Li L, Hanson JA, Stohlman SA, David CS, Jacob CO. In vivo staphylococcal superantigen-driven polyclonal Ig responses in mice: dependence upon CD4(+) cells and human MHC class II. Int Immunol 2001; 13:1291-300. [PMID: 11581174 DOI: 10.1093/intimm/13.10.1291] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Staphylococcal enterotoxin (SE) B and seven other staphylococcal superantigens (SAg), despite promoting vigorous Ig production in human peripheral blood mononuclear cell cultures, are exceedingly poor at eliciting Ig responses in cultures of spleen cells from C57BL/10J (B10) or C3H/HeJ mice. In contrast, SEB elicits Ig responses in cultures of spleen cells from human MHC class II-transgenic mice. Whereas i.p. administration of SEB (0.2-20 microg) to non-transgenic B10 mice elicits very weak in vivo Ig responses, identical treatment of CD4(+) cell-intact (but not CD4(+) cell-depleted) human MHC class II-transgenic mice elicits dramatic increases in both splenic Ig-secreting cells and serum Ig levels. Over a 2-week period, the SEB-induced in vivo Ig responses peak and then plateau or fall in association with a preferential increase in splenic CD8(+) cells. Nevertheless, in vivo depletion of CD8(+) cells has no sustained effect on SEB-driven Ig responses. Taken together, these observations demonstrate that the effects of SAg on in vivo humoral immune responses are highly CD4(+) cell dependent, are substantially CD8(+) cell independent and can be successfully investigated using human MHC class II-transgenic mice. This model system may be useful in investigating the polyclonally activating effects of microbial products (prototypic environmental insults) on the development of systemic autoimmunity.
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Affiliation(s)
- W Stohl
- Division of Rheumatology and Immunology, Keck School of Medicine, University of Southern California, 2011 Zonal Avenue, HMR 711, Los Angeles, CA 90033, USA
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12
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Roberts AI, Blumberg RS, Christ AD, Brolin RE, Ebert EC. Staphylococcal enterotoxin B induces potent cytotoxic activity by intraepithelial lymphocytes. Immunology 2000; 101:185-90. [PMID: 11012771 PMCID: PMC2327067 DOI: 10.1046/j.1365-2567.2000.00088.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In food poisoning, Staphylococcus aureus secretes staphylococcal enterotoxin B (SEB), a superantigen that causes intense T-cell proliferation and cytotoxicity. The effects of SEB on lytic activity by human intestinal intraepithelial lymphocytes (IEL) were investigated. Jejunal IEL, from morbidly obese individuals undergoing gastric bypass operations, were tested for SEB-induced cytotoxicity against C1R B-lymphoblastoid cells, HT-29 adenocarcinoma cells, or CD1d-transfected cells using the 51Cr-release assay. Fas and Fas ligand expression were detected by immunofluorescence and flow cytometry and soluble ligand by enzyme-linked immunosorbent assay (ELISA). In the presence of SEB, IEL became potently cytotoxic against C1R cells and interferon-gamma (IFN-gamma)-precultured HT-29 cells, causing 55+/-10% and 31+/-6% lysis, respectively, greater than that by phytohaemagglutinin (PHA)-, interleukin-2 (IL-2)-, or anti-T-cell receptor (TCR)-activated IEL. SEB-stimulated peripheral blood (PB) CD8+ T cells lysed similar numbers of C1R cells but fewer HT-29 cells (53+/-13% and 8+/-5%, respectively). IEL killing of C1R cells involved interaction of major histocompatibility complex (MHC) class II with TCR, CD2 with CD58, and CD11a with CD54, and was perforin mediated. SEB-induced IEL lysis of HT-29 cells, in contrast, was caused by an unknown target cell structure, not MHC class II or CD1d, and resulted from a combination of perforin and Fas-mediated events. The potent cytotoxic activities of IEL promoted by SEB utilize two different mechanisms, depending on the surface receptors expressed by the target cells.
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Affiliation(s)
- A I Roberts
- Department of Medicine, UMDNJ-Robert Wood Johnson Medical School, New Brunswick, NJ 08903, USA
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13
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Gregory S, Zilber MT, Choqueux C, Mooney N, Charron D, Gelin C. Role of the CD1a molecule in the superantigen-induced activation of MHC class II negative human thymocytes. Hum Immunol 2000; 61:427-37. [PMID: 10773345 DOI: 10.1016/s0198-8859(00)00107-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Bacterial superantigens (Sag) are potent activators of T cells. This T-cell activation has been described as an MHC class II dependent phenomenon. We have observed that human thymocytes depleted of MHC class II positive cells are still able to proliferate in response to the staphylococcal enterotoxin A (SEA). This proliferation was clearly inhibited by the addition of monoclonal antibodies directed against the CD1a molecule. In contrast, monoclonal antibodies directed against the CD1b and CD1c molecules have no effect on the Sag-induced activation of the CD2 (+) MHC class II (-) thymocytes. We next examined the ability of the CD1a molecule to transmit transmembrane signals. Results obtained indicate that CD1a ligation on these thymocytes induced tyrosine phosphorylation of the p56(lck) tyrosine kinase. Signal transduction via CD1a is further confirmed by the observation of a significant intracellular calcium flux (Ca(i)(++)) in thymocytes following CD1a engagement. These data demonstrate that CD1a ligation induces a signal transduction pathway which has a potential role in the bacterial superantigen-induced activation of human CD2 (+) MHC class II (-) thymocytes.
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Affiliation(s)
- S Gregory
- INSERM U396, Institut d'Hématologie, Hôpital Saint-Louis, Paris, France
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14
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Macphail S. Superantigens: mechanisms by which they may induce, exacerbate and control autoimmune diseases. Int Rev Immunol 1999; 18:141-80. [PMID: 10614742 DOI: 10.3109/08830189909043022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Superantigens are polypeptide molecules produced by a broad range of infectious microorganisms which elicit excessive and toxic T-cell responses in mammalian hosts. In light of this property and the fact that autoimmune diseases are frequently the sequelae of microbial infections, it has been suggested that superantigens may be etiologic agents of autoreactive immunological responses resulting in initiation, exacerbation or relapse of autoimmune diseases. This article relates the biology of superantigens to possible mechanisms by which they may exert these activities and reviews the evidence for their roles in various human and animal models of autoimmune disease. Finally, a mechanism of active suppression by superantigen-activated CD4+ T-cells that could be exploited for therapy as well as prophylaxis of human autoimmune diseases is proposed.
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Affiliation(s)
- S Macphail
- Department of Surgery, North Shore University Hospital, New York University School of Medicine and Cornell University Medical College, Manhasset, USA.
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15
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Wright AD, Chapes SK. Cross-linking staphylococcal enterotoxin A bound to major histocompatibility complex class I is required for TNF-alpha secretion. Cell Immunol 1999; 197:129-35. [PMID: 10607430 DOI: 10.1006/cimm.1999.1571] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The mechanism of how superantigens function to activate cells has been linked to their ability to bind and cross-link the major histocompatibility complex class II (MHCII) molecule. Cells that lack the MHCII molecule also respond to superantigens, however, with much less efficiency. Therefore, the purpose of this study was to confirm that staphylococcal enterotoxin A (SEA) could bind the MHCI molecule and to test the hypothesis that cross-linking SEA bound to MHCII-deficient macrophages would induce a more robust cytokine response than without cross-linking. We used a capture enzyme-linked immunosorbent assay and an immunprecipitation assay to directly demonstrate that MHCI molecules bind SEA. Directly cross-linking MHCI using monoclonal antibodies or cross-linking bound SEA with an anti-SEA antibody or biotinylated SEA with avidin increased TNF-alpha and IL-6 secretion by MHCII(-/-) macrophages. The induction of a vigorous macrophage cytokine response by SEA/anti-SEA cross-linking of MHCI offers a mechanism to explain how MHCI could play an important role in superantigen-mediated pathogenesis.
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Affiliation(s)
- A D Wright
- Division of Biology, Kansas State University, Manhattan, Kansas 66506, USA
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16
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Shankar G, Johnson J, Kuschel L, Richins M, Burnham K. Protein-kinase-specific inhibitors block Langerhans' cell migration by inhibiting interleukin-1alpha release. Immunology 1999; 96:230-5. [PMID: 10233700 PMCID: PMC2326744 DOI: 10.1046/j.1365-2567.1999.00680.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Previous studies have shown that depletion of Langerhans' cells (LC) from murine epidermis by the superantigen, staphylococcal enterotoxin A (SEA) involves interleukin-1alpha (IL-1alpha) and is inhibitable by agents that block G-protein-associated kinases. The purpose of this study was to determine whether specific kinase inhibitors block LC depletion by inhibiting IL-1alpha release and to ascertain whether LC depletion by SEA involves cell migration. These goals were addressed by measuring the IL-1alpha release within whole or LC-depleted epidermal cell suspensions in the presence of SEA and/or H-7 (an inhibitor of protein kinase C) or H-8 (an inhibitor of G-protein-associated kinases) and by examining the migration of cells with LC markers in SEA-treated skin sections. The results suggest that LC depletion by SEA involves migration and that this migration is blocked by protein kinase inhibitors, at least in part, through inhibition of SEA-induced IL-1alpha release by epidermal cells.
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Affiliation(s)
- G Shankar
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Oklahoma, USA
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17
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Fuller CL, Braciale VL. Selective Induction of CD8+ Cytotoxic T Lymphocyte Effector Function by Staphylococcus Enterotoxin B. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.161.10.5179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Upon encounter with its antigenic stimulus, CTL characteristically proliferate, produce cytokines, and lyse the Ag-presenting cell in an attempt to impede further infection. Superantigens are extremely efficient immunostimulatory proteins that promote high levels of proliferation and massive cytokine production in reactive T cells. We compared the activation of murine influenza-specific CD8+ CTL clones stimulated with either influenza peptide or the superantigen staphylococcus enterotoxin B (SEB). We found that influenza peptide/MHC and SEB appeared equally capable of eliciting proliferation and IFN-γ production. However, while influenza peptide/MHC elicited both perforin- and Fas ligand (FasL)/Fas (CD95L/CD95)-mediated cytolytic mechanisms, SEB was unable to trigger perforin-mediated cytolysis or serine esterase release. Examination of intracellular Ca2+ mobilization events revealed that the ability to trigger intracellular Ca2+ flux was not comparable between influenza peptide and SEB. SEB stimulated only a small rise in levels of intracellular Ca2+, at times indistinguishable from background. These findings indicate that the short-term cytolytic potential of superantigen-activated CD8+ CTL clones appears to be restricted to FasL/Fas (CD95L/CD95) mediated cytolysis.
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Affiliation(s)
- Claudette L. Fuller
- Department of Microbiology and Beirne B. Carter Center for Immunology Research, Health Sciences Center, University of Virginia, Charlottesville, VA 22908
| | - Vivian Lam Braciale
- Department of Microbiology and Beirne B. Carter Center for Immunology Research, Health Sciences Center, University of Virginia, Charlottesville, VA 22908
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18
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Lamphear JG, Bohach GA, Rich RR. Structural Dichotomy of Staphylococcal Enterotoxin C Superantigens Leading to MHC Class II-Independent Activation of T Lymphocytes. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.160.5.2107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
We have recently characterized an MHC class II-deficient human cell line, SW480, that supports the proliferation of purified human T cells in the presence of the staphylococcal enterotoxin and superantigen SEC1, but not the closely related isotypes SEC2 or SEC3. We now investigate the structural basis of this dichotomy and explore possible mechanisms that may account for it. Differences in activity between SEC1 and SEC2 were not attributable to differences in biochemical modification, to differences in Vβ specificity, or to the potential to induce anergy. SEC2 inhibited SEC1-mediated T cell activation in the presence of SW480 cells, suggesting that SEC2 could compete with SEC1 for binding to the TCR but was unable to productively signal through the TCR. Utilizing a panel of hybrid enterotoxins we identified specific amino acids near the NH2-terminus of SEC1 that abrogated MHC class II-independent T cell activation, yet did not alter potency in the presence of class II+ APC. These residues mapped to the putative TCR binding domain of SEC1, and suggest that subtle differences in TCR binding affinity or the topology of the SEC1-TCR interaction can compensate for the lack of MHC class II and hence promote T cell proliferation.
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Affiliation(s)
| | - Gregory A. Bohach
- ‡Department of Microbiology, Molecular Biology and Biochemistry, University of Idaho, Moscow, ID 83843
| | - Robert R. Rich
- *Microbiology and Immunology, and
- †Medicine, Baylor College of Medicine, Houston, TX 77030; and
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19
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Wahlsten JL, Ramakrishnan S. Separation of Function Between the Domains of Toxic Shock Syndrome Toxin-1. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.160.2.854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Toxic shock syndrome toxin-1 (TSST1) is a superantigenic exotoxin produced by certain strains of Staphylococcus aureus. Structurally, TSST1 is composed of two domains: residues determined by crystallography to directly interact with MHC II molecules reside within the N-terminal domain, while TSST1 residues critical for superantigenicity are within the C-terminal domain. In this study, we expressed the individual N- and C-terminal domains of TSST1 in Escherichia coli and studied their biologic activities. The TSST1 N-terminal domain (TSST(1–87)) did not induce proliferation of human PBLs or release of TNF-β, but did induce TNF-α release. However, TSST1-elicited proliferation and release of both TNF isoforms were inhibited by a molar excess of TSST(1–87). The TSST1 C-terminal domain (TSST(88–194)) did not bind MHC II molecules, yet it elicited production of TNF-α and TNF-β, and induced TCR Vβ-specific proliferation similarly to intact TSST1. When covalently cross-linked to tumor cells, TSST(88–194) elicited a local in vivo antitumor response indistinguishable from TSST1. Although intact TSST1 causes lethal shock in vivo, the individual domains of this molecule may have therapeutic potential: the N-terminal domain to antagonize lymphocyte activation and TNF release during acute TSST1-precipitated toxic shock syndrome, and the C-terminal domain to stimulate antitumor responses without MHC II binding.
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Affiliation(s)
| | - S. Ramakrishnan
- University of Minnesota, Department of Pharmacology, Minneapolis, MN 55455
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20
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Lamphear JG, Stevens KR, Rich RR. Intercellular Adhesion Molecule-1 and Leukocyte Function-Associated Antigen-3 Provide Costimulation for Superantigen-Induced T Lymphocyte Proliferation in the Absence of a Specific Presenting Molecule. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.160.2.615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Bacterial superantigens can bind TCR in the absence of MHC class II molecules and activate T lymphocytes when cocultured with certain class II-deficient accessory cells. It has not been determined, however, whether these accessory cells provide direct costimulation to the T cell or serve to present superantigens via a nonconventional ligand. We have identified a human adenocarcinoma cell line, SW480, that assists in the activation of human T cells by the staphylococcal enterotoxins B (SEB), C1 (SEC1), and D (SED), but not SEA, SEC2, SEC3, or SEE. SW480 cells did not express class II molecules, and anti-class II mAbs did not inhibit T cell proliferation, supporting the hypothesis that class II is not absolutely required for enterotoxin-mediated T cell activation. The TCR Vβ profile of T cells stimulated by SEB plus SW480 cells was similar to that of T cells stimulated by SEB plus class II+ APC, indicating that TCR-SEB interactions were preserved in the absence of class II molecules. Binding studies failed to detect specific association of SEB with SW480 cells, suggesting that SW480 cells do not express receptors for enterotoxin. SEB coupled to beads, however, stimulated T cell proliferation, but only in the presence of SW480 cells. SW480 cells express both ICAM-1 and LFA-3 molecules, and the addition of Abs to these receptors inhibited T cell proliferation. These findings support a model in which certain enterotoxins engage the TCR independent of MHC class II or other specific presenting molecules and induce T cell proliferation with signals provided by nonconventional accessory cells.
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Affiliation(s)
| | | | - Robert R. Rich
- *Microbiology and Immunology and
- †Medicine, Baylor College of Medicine, Houston, TX 77030
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21
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Hamad AR, Marrack P, Kappler JW. Transcytosis of staphylococcal superantigen toxins. J Exp Med 1997; 185:1447-54. [PMID: 9126925 PMCID: PMC2196287 DOI: 10.1084/jem.185.8.1447] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/1996] [Revised: 02/14/1997] [Indexed: 02/04/2023] Open
Abstract
Staphylococcus aureus produces a set of proteins (e.g., staphylococcal enterotoxin A [SEA], SEB, toxic shock syndrome toxin 1 [TSST-1]) which act both as superantigens (SAgs) and toxins. Although their mode of action as SAgs is well understood, little is known about how they enter the body via the intestine and cause food poisoning. To examine this problem we used an in vitro culture system to study the capacity of class II MHC-negative human intestinal epithelial cells (Caco-2) to transcytose several staphylococcal toxins. We found that Caco-2 cells are capable of dose-dependent, facilitated transcytosis of SEB and TSST-1, but not SEA. We extended these studies in vivo in mice by showing that ingested SEB appears in the blood more efficiently than SEA. Our data suggest that these toxins can cross the epithelium in an immunologically intact form. These results may have important implications for the pathogenesis of food poisoning.
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Affiliation(s)
- A R Hamad
- Department of Medicine, National Jewish Medical and Research Center, Denver, Colorado 80206, USA
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22
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Abstract
Superantigens are potent modulators of the immune system. Some of their biological and immunological properties are reviewed here with special attention to their potential significance for cutaneous inflammation, specific skin immune responses and skin diseases.
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Affiliation(s)
- J Saloga
- Department of Dermatology, University of Mainz, Germany
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23
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Lando PA, Dohlsten M, Ohlsson L, Kalland T. Tumor-reactive superantigens suppress tumor growth in humanized SCID mice. Int J Cancer 1995; 62:466-71. [PMID: 7635573 DOI: 10.1002/ijc.2910620418] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Superantigens are extremely potent activators of T lymphocytes. To develop a tumor-reactive superantigen for cancer therapy, we made a recombinant fusion protein of the superantigen staphylococcal enterotoxin A (SEA) and the Fab region of the C242 monoclonal antibody (C242Fab-SEA), which recognize human colon carcinoma cells. The therapeutic effect of C242Fab-SEA on colon-cancer growth was examined in lymphocyte-engrafted humanized SCID mice bearing intraperitoneally growing Colo205 colon carcinomas. i.v. injections of C242Fab-SEA significantly inhibited tumor growth. The anti-tumor effect required the presence of human T cells in the SCID mice. Optimal therapeutic effects were seen with C242Fab-SEA, but not with C242Fab fragment or SEA alone, demonstrating that both entities of the fusion protein were required. C242Fab-SEA-treated tumors showed a massive infiltration of T cells in the tumor parenchyme, and was accompanied by enhanced expression of ICAM-I and HLA-DR on the tumor cells. The results demonstrate that Fab-SEA fusion proteins convey superantigenicity on tumor cells which evoke T-cell-dependent suppression of tumor growth.
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Affiliation(s)
- P A Lando
- Department of Tumor Immunology, Wallenberg Laboratory, University of Lund, Sweden
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24
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Abstract
The recent discovery of the mode of interaction between a group of microbial proteins known as superantigens and the immune system has opened a wide area of investigation into the possible role of these molecules in human diseases. Superantigens produced by certain viruses and bacteria, including Mycoplasma species, are either secreted or membrane-bound proteins. A unique feature of these proteins is that they can interact simultaneously with distinct receptors on different types of cells, resulting in enhanced cell-cell interaction and triggering a series of biochemical reactions that can lead to excessive cell proliferation and the release of inflammatory cytokines. However, although superantigens share many features, they can have very different biological effects that are potentiated by host genetic and environmental factors. This review focuses on a group of secreted pyrogenic toxins that belong to the superantigen family and highlights some of their structural-functional features and their roles in diseases such as toxic shock and autoimmunity. Deciphering the biological activities of the various superantigens and understanding their role in the pathogenesis of microbial infections and their sequelae will enable us to devise means by which we can intervene with their activity and/or manipulate them to our advantage.
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Affiliation(s)
- M Kotb
- Department of Surgery, University of Tennessee, Memphis, USA
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25
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Dohlsten M, Abrahmsén L, Björk P, Lando PA, Hedlund G, Forsberg G, Brodin T, Gascoigne NR, Förberg C, Lind P. Monoclonal antibody-superantigen fusion proteins: tumor-specific agents for T-cell-based tumor therapy. Proc Natl Acad Sci U S A 1994; 91:8945-9. [PMID: 8090750 PMCID: PMC44723 DOI: 10.1073/pnas.91.19.8945] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The bacterial superantigen staphylococcal enterotoxin A (SEA) is an extremely potent activator of T lymphocytes when presented on major histocompatibility complex (MHC) class II molecules. To develop a tumor-specific superantigen for cancer therapy, we have made a recombinant fusion protein of SEA and the Fab region of the C215 monoclonal antibody specific for human colon carcinoma cells. SEA as part of a fusion protein showed a > 10-fold reduction in MHC class II binding compared to native SEA, and accordingly, the affinity of the FabC215-SEA fusion protein for the C215 tumor antigen was approximately 100-fold stronger than to MHC class II molecules. The FabC215-SEA fusion protein efficiently targeted T cells to lyse C215+ MHC class II- human colon carcinoma cells, which demonstrates functional substitution of the MHC class II-dependent presentation of SEA with tumor specificity. Treatment of mice carrying B16 melanoma cells expressing a transfected C215 antigen resulted in 85-99% inhibition of tumor growth and allowed long-term survival of animals. The therapeutic effect was dependent on antigen-specific targeting of the FabC215-SEA fusion protein, since native SEA and an antigen-irrelevant FabC242-SEA fusion protein did not influence tumor growth. The results suggest that Fab-SEA fusion proteins convey superantigenicity on tumor cells, which evokes T cells to suppress tumor growth.
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MESH Headings
- Antibodies, Monoclonal/chemistry
- Antigens, Neoplasm/immunology
- Base Sequence
- Carcinoma/therapy
- Cloning, Molecular
- Colonic Neoplasms/therapy
- Cytotoxicity, Immunologic
- DNA Primers/chemistry
- Enterotoxins/administration & dosage
- Histocompatibility Antigens Class II/metabolism
- Humans
- Immunity, Cellular
- Immunotherapy
- Molecular Sequence Data
- Neoplasm Transplantation
- Neoplasms, Experimental/therapy
- Receptors, Antigen, T-Cell/metabolism
- Recombinant Fusion Proteins
- Superantigens/chemistry
- T-Lymphocytes, Cytotoxic/immunology
- Transplantation, Heterologous
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Affiliation(s)
- M Dohlsten
- Wallenberg Laboratory, Department of Tumor Immunology, University of Lund, Sweden
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26
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Beharka AA, Armstrong JW, Iandolo JJ, Chapes SK. Binding and activation of major histocompatibility complex class II-deficient macrophages by staphylococcal exotoxins. Infect Immun 1994; 62:3907-15. [PMID: 8063407 PMCID: PMC303047 DOI: 10.1128/iai.62.9.3907-3915.1994] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Macrophages from C2D transgenic mice deficient in the expression of major histocompatibility complex (MHC) class II proteins were used to identify binding sites for superantigens distinct from the MHC class II molecule. Iodinated staphylococcal enterotoxins A and B (SEA and SEB) and exfoliative toxins A and B (ETA and ETB) bound to C2D macrophages in a concentration-dependent and competitive manner. All four toxins increased F-actin concentration within 30 s of their addition to C2D macrophages, indicating that signal transduction occurred in response to toxin in the absence of class II MHC. Furthermore, ETA, ETB, SEA, and, to a lesser extent, SEB induced C2D macrophages to produce interleukin 6. Several molecular species on C2D macrophages with molecular masses of 140, 97, 61, 52, 43, and 37 kDa bound SEA in immunoprecipitation experiments. These data indicate the presence of novel, functionally active toxin binding sites on murine macrophages distinct from MHC class II molecules.
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Affiliation(s)
- A A Beharka
- Division of Biology, Kansas State University, Manhattan 66506-4901
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27
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Green JM, Zheng XG, Shimizu Y, Thompson CB, Turka LA. T cell receptor stimulation, but not CD28 costimulation, is dependent on LFA-1-mediated events. Eur J Immunol 1994; 24:265-72. [PMID: 7517362 DOI: 10.1002/eji.1830240141] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Accessory molecules play a crucial role in the development of the T cell response to antigenic challenge. In this manuscript we specifically examine the role of two accessory molecules, CD28 and LFA-1, in modulating the T cell proliferative response to a variety of stimuli. We demonstrate that the proliferation induced by staphylococcal enterotoxins A and B in combination with CD28 costimulation is dependent on LFA-1-mediated events. This requirement for LFA-1 is independent of T cell-accessory cell adhesion. Similarly, an allogeneic mixed lymphocyte reaction, which has previously been shown to be a CD28-dependent response, can be inhibited by blockade of LFA-1. This suggests LFA-1 plays an essential role in these responses, either by enhancing intercellular adhesion or by an independent signal transduction event. In contrast, when the primary activating stimulus is delivered by immobilized anti-CD3 antibody or by PMA, and the secondary stimulus by either alpha-CD28 or cell-bound CD28 ligand B7, there is no requirement for LFA-1. In addition, we demonstrate that cross-linking of LFA-1 with immobilized monoclonal antibody, or engagement of LFA-1 with ICAM-1 expressed on the surface of a CHO cell, provide an insufficient costimulus for T cell proliferation initiated by enterotoxin, immobilized alpha-CD3 or phorbol ester. Our data suggests that LFA-1, in contrast to CD28, functions not as a costimulatory molecule, but serves primarily to modulate the signal delivered through the T cell receptor.
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Affiliation(s)
- J M Green
- Department of Internal Medicine and Microbiology, University of Michigan Medical Center, Ann Arbor 48109
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28
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Williams O, Gonzalo JA, Martínez C. Staphylococcal enterotoxin B promotes deletion and functional inactivation of CD4V beta 8-positive cells in the absence of CD8 T cells. Scand J Immunol 1993; 38:254-8. [PMID: 8102808 DOI: 10.1111/j.1365-3083.1993.tb01722.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The staphylococcal enterotoxins stimulate discrete subsets of T cells depending on their expression of particular V genes. Among these, staphylococcal enterotoxin B (SEB) vigorously stimulates V beta 8+ cells. This stimulation results in proliferation of both CD4+V beta 8+ and CD8+ T cells and eventually to anergy and clonal deletion in the former subset. We have examined the possible role of CD8+ T cells in the response of CD4+ cells to SEB, by in vivo CD8+ T-cell-depletion. We found no qualitative difference in the responses of untreated and CD8+ T-cell depleted mice to SEB; however, a small quantitative difference in deletion was observed. Thus it appears that on the whole the response of CD4+V beta 8+ T cells to SEB is independent of CD8+ T-cell effector function, although the latter may play a partial role.
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Affiliation(s)
- O Williams
- Centro de Biología Molecular (CSIC), Universidad Autónoma, Madrid, Spain
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29
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Chapes SK, Hoynowski SM, Woods KM, Armstrong JW, Beharka AA, Iandolo JJ. Staphylococcus-mediated T-cell activation and spontaneous natural killer cell activity in the absence of major histocompatibility complex class II molecules. Infect Immun 1993; 61:4013-6. [PMID: 8359928 PMCID: PMC281111 DOI: 10.1128/iai.61.9.4013-4016.1993] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
We used major histocompatibility complex class II antigen-deficient transgenic mice to show that in vitro natural killer cell cytotoxicity and T-cell activation by staphylococcal exotoxins (superantigens) are not dependent upon the presence of major histocompatibility complex class II molecules. T cells can be activated by exotoxins in the presence of exogenously added interleukin 1 or 2 or in the presence of specific antibody without exogenously added cytokines.
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Affiliation(s)
- S K Chapes
- Division of Biology, Kansas State University, Manhattan 66506
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Kalland T, Dohlsten M, Lind P, Sundstedt A, Abrahmsén L, Hedlund G, Björk P, Lando PA, Björklund M. Monoclonal antibodies and superantigens: a novel therapeutic approach. MEDICAL ONCOLOGY AND TUMOR PHARMACOTHERAPY 1993; 10:37-47. [PMID: 8258993 DOI: 10.1007/bf02987767] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have developed a monoclonal antibody (mAb) based therapy intended for the treatment of solid tumors utilizing both main arms of the immune system by incorporating the colon carcinoma recognizing mAb C215 and the T cell activating bacterial staphylococcal enterotoxin A (SEA) in a single hybrid molecule. The recombinant tumor specific superantigen C215-SEA retained excellent antigen binding properties while the binding to MHC class II was markedly reduced and should allow targeting of a large fraction of T cells to tumors in vivo. C215-SEA mediated T cell killing of C215 expressing tumor cells irrespective of their expression of MHC class II antigens and induced levels of IFN-gamma and TNF in mononuclear cells sufficient to completely suppress the growth of colon carcinoma cells in vitro. In initial studies of anti-tumor effects, C215Fab-SEA was found to markedly inhibit the growth of colon carcinoma cells transplanted to Scid mice adoptively transferred with human mononuclear cells.
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Affiliation(s)
- T Kalland
- Kabi Pharmacia Oncology, Lund, Sweden
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Lando PA, Dohlsten M, Hedlund G, Akerblom E, Kalland T. T cell killing of human colon carcinomas by monoclonal-antibody-targeted superantigens. Cancer Immunol Immunother 1993; 36:223-8. [PMID: 8439985 PMCID: PMC11038446 DOI: 10.1007/bf01740903] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/1992] [Accepted: 11/02/1992] [Indexed: 01/30/2023]
Abstract
The bacterial superantigen staphylococcal enterotoxin A (SEA) induces T cell activation as well as directing activated T cells to kill major-histocompatibility-complex-class-II-expressing tumours such as freshly prepared leukemia cells. We now report that conjugates of SEA and the colon-carcinoma-reactive mAb C215 mediate T-cell-dependent killing of freshly isolated cells obtained from surgical specimens of human colon carcinomas. Cytotoxicity was observed at nanomolar concentrations of conjugate while no or very low effects were seen with the mAb C215 or SEA alone. Tumour-infiltrating lymphocytes (TIL) did not exert any cytotoxicity against conjugate-treated tumour cells immediately after isolation. In vitro culture of TIL with interleukin-2 and SEA resulted in SEA-mAb-conjugate-dependent killing of freshly isolated tumour cells. This suggests that mAb-SEA conjugates may be of potential use to target T lymphocytes, including TIL, against colon carcinoma cells in vivo.
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MESH Headings
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/immunology
- Antibodies, Neoplasm/immunology
- Antibody-Dependent Cell Cytotoxicity
- Antigens, Tumor-Associated, Carbohydrate/immunology
- Carcinoma/immunology
- Colonic Neoplasms/immunology
- Dose-Response Relationship, Immunologic
- Enterotoxins/administration & dosage
- Humans
- Immunity, Cellular
- Immunotherapy
- In Vitro Techniques
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Recombinant Proteins/immunology
- T-Lymphocytes/immunology
- Tumor Cells, Cultured
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Affiliation(s)
- P A Lando
- Kabi Pharmacia Therapeutics, Lund, Sweden
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Kalland T, Dohlsten M, Abrahmsén L, Hedlund G, Björk P, Lando PA, Sundstedt A, Akerblom E, Lind P. Targeting of superantigens. CELL BIOPHYSICS 1993; 22:147-64. [PMID: 7889537 DOI: 10.1007/bf03033872] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The bacterial superantigen staphylococcal enterotoxin A (SEA) is an extremely potent activator of T lymphocytes when presented on MHC class II antigens. In order to induce T lymphocytes to reject a tumor, we substituted the specificity of SEA for MHC class II molecules with specificity for tumor cells by combining SEA with a MAb recognizing colon carcinomas. Chemical conjugates or recombinant fusion proteins of the MAb C215 and SEA retained excellent antigen binding properties whereas the binding to MHC class II was markedly reduced. The hybrid proteins directed SEA responsive T cells to tumors with specificity determined by the specificity of the MAb. Significant tumor cell killing was obtained at picomolar concentrations of the hybrid proteins and was the result of direct cell mediated by cytotoxicity as well as production of tumoricidal cytokines by T cells. Targeting of superantigens represents a novel approach to specific immunomodulation and deserves further study as a potential therapy for malignant disease.
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Affiliation(s)
- T Kalland
- Kabi Pharmacia Oncology, Lund, Sweden
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Macphail S, Stutman O. H-2 I-E molecules isolated from Mls1a stimulatory cells do not activate Mls1a-responsive T cells but do present exogenous staphylococcal enterotoxins. Eur J Immunol 1993; 23:90-5. [PMID: 8419192 DOI: 10.1002/eji.1830230115] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The T cell response to allogeneic murine Mls determinants is not H-2 restricted but is dependent on H-2 class II molecules on the Mls-expressing stimulator cells. We have tested planar membranes containing H-2 class II I-E molecules alone or with I-A molecules for their ability to activate a panel of Mls1a-specific T hybrids. Despite the ability of the planar membranes to activate an alloreactive T hybrid and to present staphylococcal enterotoxins or an antigenic peptide to appropriately responsive T hybrids, they failed to stimulate the Mls1a-specific T hybrids. These findings, in the light of the various controls demonstrating sufficiency of the I-E molecules in the planar membranes, indicate that Mls1a determinants are not covalently bound to I-E molecules; the two molecular species are thus either not physically associated or are linked by a relatively weak interaction. In addition, our experiments show that isolated I-E molecules but not I-A molecules present staphylococcal enterotoxins A and B to two independently derived T hybrids expressing T cell receptor V beta 1, V beta 2 and V beta 6 elements.
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Affiliation(s)
- S Macphail
- Department of Surgery, North Shore University Hospital, Manhasset, NY 11030
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Bowness P, Moss PA, Tranter H, Bell JI, McMichael AJ. Clostridium perfringens enterotoxin is a superantigen reactive with human T cell receptors V beta 6.9 and V beta 22. J Exp Med 1992; 176:893-6. [PMID: 1512551 PMCID: PMC2119363 DOI: 10.1084/jem.176.3.893] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Candidate superantigens were screened for their ability to induce lysis of human histocompatibility leukocyte antigen class II-positive targets by human CD8+ influenza-specific cytotoxic T cell (CTL) lines. Clostridium perfringens enterotoxin (CPET) induced major histocompatibility complex unrestricted killing by some but not all CTL lines. Using "anchored" polymerase chain reactions, CPET was shown to selectively stimulate peripheral blood lymphocytes bearing T cell receptor V beta 6.9 and V beta 22 in five healthy donors. V beta 24, V beta 21, V beta 18, V beta 5, and V beta 6.1-5 appeared to be weakly stimulated. Antigen processing was not required for CPET to induce proliferation. Like the staphylococcal enterotoxins, CPET is a major cause of food poisoning. These data suggest that superantigenic and enterotoxigenic properties may be closely linked.
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Affiliation(s)
- P Bowness
- Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, UK
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Komisar J, Rivera J, Vega A, Tseng J. Effects of staphylococcal enterotoxin B on rodent mast cells. Infect Immun 1992; 60:2969-75. [PMID: 1377185 PMCID: PMC257261 DOI: 10.1128/iai.60.7.2969-2975.1992] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Staphylococcal enterotoxin B (SEB) was tested in rodent mast cell cultures for the release of serotonin. Both rat RBL-2H3 mast cells and murine peritoneal cells released serotonin after SEB stimulation in culture. Release of serotonin in RBL-2H3 cells depended on the concentration of SEB; an appreciable release was seen at 50 micrograms/ml. The release of serotonin was not due to cell death. Serotonin release could be enhanced by bradykinin but not by vasoactive intestinal peptide, substance P, lipopolysaccharide from Salmonella typhimurium, the calcium ionophore A23187, acetylcholine, adenosine, 5-hydroxyeicosatetraenoic acid, indomethacin, or phorbol myristate acetate. SEB bound directly to the membrane of RBL-2H3 mast cells, and the SEB-binding site, the presumptive receptor, appeared to be a protein. The SEB receptor could not be capped under membrane-capping conditions, and serotonin release could not be enhanced by attempts to cross-link the receptor. These results suggest that mast cells may be an important cell type involved in SEB toxicosis and that release of serotonin may be enhanced by activation of the kinin-kallikrein system.
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Affiliation(s)
- J Komisar
- Department of Experimental Pathology, Walter Reed Army Institute of Research, Washington, D.C. 20307-5100
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Dohlsten M, Hedlund G, Akerblom E, Lando PA, Kalland T. Monoclonal antibody-targeted superantigens: a different class of anti-tumor agents. Proc Natl Acad Sci U S A 1991; 88:9287-91. [PMID: 1924393 PMCID: PMC52699 DOI: 10.1073/pnas.88.20.9287] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The bacterial superantigen staphylococcal enterotoxin (SE) A (SEA) directs cytotoxic T lymphocytes (CTLs) expressing particular sequences of the T-cell receptor (TCR) beta chain to lyse tumor cells expressing major histocompatibility complex (MHC) class II molecules, which serve as receptors for SEs. We now report that chemical conjugates of SEA and the colon carcinoma-reactive monoclonal antibodies (mAbs) C215 or C242 mediate T cell-dependent destruction of colon carcinoma cells lacking MHC class II molecules. SEA was covalently linked to the mAbs C215 and C242 via a PEG-based hydrophilic spacer. The C215-SEA conjugate targeted CD4+ as well as CD8+ CTLs to lyse a panel of colon carcinoma cells lacking MHC class II molecules. T-cell recognition of mAb-SEA conjugates was SEA specific, since SEB-selective T-cell lines with potent cytotoxic activity towards Raji cells coated with SEB did not respond to the C215-SEA conjugate. Unconjugated SEA did not induce T-cell lysis of MHC class II- colon carcinoma cells but efficiently directed CTLs against MHC class II+ Raji cells and certain interferon-treated MHC class II+ colon carcinoma cells. These results suggest that SEA-mAb conjugates retain the SEA-related selectivity for certain TCR beta-chain variable region (V beta) sequences but, in contrast to unconjugated SEA, mediate the TCR interaction in a MHC class II-independent manner. The cytotoxic activity mediated by C215-SEA and C242-SEA conjugates was blocked by excess of C215 mAb and C242 mAb, respectively, showing that the specificity in the targeting of mAb-SEA conjugates is defined by the antigen reactivity of the mAb. These results demonstrate that bacterial superantigens may be successfully conjugated to mAb with preserved T cell-activating capacity. The circumvention of MHC class II binding of SEs by conjugation to mAb suggests that such conjugates may find general application as antitumor agents, taking advantage of the extreme T cell-activating potency of superantigens.
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Affiliation(s)
- M Dohlsten
- Kabi Pharmacia Therapeutics AB, Lund, Sweden
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37
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Affiliation(s)
- T Herrmann
- Ludwig Institute for Cancer Research, Lausanne Branch, Epalinges, Switzerland
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Kalland T, Hedlund G, Dohlsten M, Lando PA. Staphylococcal enterotoxin-dependent cell-mediated cytotoxicity. Curr Top Microbiol Immunol 1991; 174:81-92. [PMID: 1687000 DOI: 10.1007/978-3-642-50998-8_6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- T Kalland
- Kabi Pharmacia Therapeutics AB, Lund, Sweden
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