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Sabu G, De S. Be 2+ Causes Hypersensitivity but Mg 2+ and Ca 2+ Do Not─Favorable Metal Coordination Is the Key for Differential Allosteric Modulation and Binding Affinities. J Phys Chem B 2023; 127:10326-10337. [PMID: 38010277 DOI: 10.1021/acs.jpcb.3c05461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Although the ion selectivity of metalloproteins has been well established, selective metal antigen recognition by immunoproteins remains elusive. One such case is the recognition of the Be2+ ion against its heavier congeners, Mg2+ and Ca2+, by the human leukocyte antigen immunoprotein (HLA-DP2), leading to immunotoxicity. Integrating with our previous mechanistic study on Be2+ toxicity, herein, we have explored the basis of characteristic nontoxicity of Mg2+ and Ca2+ ions despite their in vivo abundance. The ion binding cleft of the HLA-DP2-peptide complex is composed of four acidic residues, p4D and p7E from the peptide and β26E and β69E from the protein. While the tetrahedral coordination site of the smaller Be2+ ion is located deep inside the cavity, hexa- to octa-coordination sites of Mg2+ and Ca2+ ions are located closer to the protein surface. The intrinsic high coordination number of Mg2+/Ca2+ ions induces allosteric modifications on the HLA-DP2_M2 surface, which are atypical for TCR recognition. Furthermore, the lower binding energy of larger Mg2+ and Ca2+ ions with the cavity residues can be correlated to the lower charge density and reduced covalent bonding nature as compared to those of the smaller Be2+ ion. In short, weak binding of Mg2+ and Ca2+ ions and the unfavorable allosteric surface modifications are probably the major determinants for the absence of Mg2+/Ca2+ ion-mediated hypersensitivity in humans.
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Affiliation(s)
- Gopika Sabu
- Department of Applied Chemistry, Cochin University of Science and Technology, Thrikakkara, Kochi 682 022, India
| | - Susmita De
- Department of Chemistry, University of Calicut, Calicut University P.O., Malappuram 673 635, Kerala, India
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Chamani S, Mobasheri L, Rostami Z, Zare I, Naghizadeh A, Mostafavi E. Heavy metals in contact dermatitis: A review. J Trace Elem Med Biol 2023; 79:127240. [PMID: 37331278 DOI: 10.1016/j.jtemb.2023.127240] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 06/01/2023] [Accepted: 06/06/2023] [Indexed: 06/20/2023]
Abstract
Contact dermatitis is an inflammatory skin reaction caused by direct contact with chemical substances in the environment and can either be irritant or allergic in nature. The clinical symptoms of contact dermatitis, include local skin rash, itching, redness, swelling, and lesions. Nowadays, 15-20% of people have some degree of contact dermatitis, which can be more or less severe. Immune responses in allergic contact dermatitis (ACD) are due to the effects of cytokines and allergen-specific CD4+ and CD8+ T cells on the skin. Acids and alkalis such as drain cleaners, plants such as poinsettias, hair colors, and nail polish remover, are all prominent causes of irritant contact dermatitis (ICDs). Heavy metals are metallic elements with a high atomic weight that are hazardous in low quantities and are known to cause dermatitis after systemic or local exposure. Nickel (Ni), chromium (Cr), lead (Pb), and copper (Cu) are among the most common heavy metals used in various industries. Metal allergies may cause ACD and also systemic contact dermatitis (SCD). Contact dermatitis is detected by laboratory tests such as patch testing, lymphocyte stimulation test (LST), and evaluation of cytokine production by primary cultures of peripheral blood mononuclear cells. This article presents an update on the epidemiological and clinical characteristics of ACD and SCD caused by three heavy metals (Cr, Cu, and Pb). Ni is not discussed due to recent coverage. Furthermore, the effects of contact sensitivity to some other heavy metals, such as gold (Au), cobalt (Co), palladium (Pd), and mercury (Hg) are discussed.
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Affiliation(s)
- Sajad Chamani
- Medical Toxicology and Drug Abuse Research Center (MTDRC), Birjand University of Medical Sciences, Birjand, Iran
| | - Leila Mobasheri
- Department of Pharmacology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Zeinab Rostami
- Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - Iman Zare
- Research and Development Department, Sina Medical Biochemistry Technologies Co. Ltd., Shiraz 7178795844, Iran
| | - Ali Naghizadeh
- Medical Toxicology and Drug Abuse Research Center (MTDRC), Birjand University of Medical Sciences, Birjand, Iran.
| | - Ebrahim Mostafavi
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA.
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Filliquist B, McKay R, Marcellin-Little DJ, Irvin JJ, Garcia TC, Vernau W, Chou PY, Kapatkin AS, Vapniarsky N. Metal reactivity is present in dogs with tibial plateau leveling osteotomy and total hip replacement implants. Am J Vet Res 2023; 84:ajvr.22.08.0141. [PMID: 36652332 DOI: 10.2460/ajvr.22.08.0141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 12/25/2022] [Indexed: 01/19/2023]
Abstract
OBJECTIVE Determine whether dogs with well-functioning orthopedic metal implants can develop metal reactivity. SAMPLE Client-owned dogs that had tibial plateau leveling osteotomy (TPLO) or total hip replacement (THR) implants for 12 months or more and control dogs with no implants. PROCEDURES Lymphocyte transformation testing was performed by exposing peripheral blood lymphocytes to nickel (Ni), chromium (Cr), cobalt (Co), or a combination of these metals. Lymphocyte proliferation was assessed with flow cytometry. Lymphocyte stimulation indexes (SIs) were calculated. A SI > 2 was considered reactive. Median SIs of dogs in response to metal exposure were compared statistically. RESULTS Samples from 10 dogs with TPLO, 12 dogs with THR, and 7 control dogs were analyzed. Six dogs out of 22 with metal implants had a reactive SI to 1 or more metals, while 2 of 7 control dogs had a SI > 2 when exposed to nickel only. When all metals were considered, no differences in metal reactivity were found between TPLO, THR, and control groups. CLINICAL RELEVANCE Metal reactivity is present in dogs and can be identified using lymphocyte transformation testing. Reactivity to Ni is present in dogs with and without metal implants. Reactivity to Co and Cr occurs in some dogs with metal implants.
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Affiliation(s)
- Barbro Filliquist
- Department of Veterinary Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA.,JD Wheat Veterinary Orthopedic Laboratory, School of Veterinary Medicine, University of California-Davis, Davis, CA
| | - Rachel McKay
- Pritchard Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California-Davis, Davis, CA
| | - Denis J Marcellin-Little
- Department of Veterinary Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA.,JD Wheat Veterinary Orthopedic Laboratory, School of Veterinary Medicine, University of California-Davis, Davis, CA
| | - Justine J Irvin
- JD Wheat Veterinary Orthopedic Laboratory, School of Veterinary Medicine, University of California-Davis, Davis, CA
| | - Tanya C Garcia
- Department of Veterinary Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA.,JD Wheat Veterinary Orthopedic Laboratory, School of Veterinary Medicine, University of California-Davis, Davis, CA
| | - William Vernau
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California-Davis, Davis, CA
| | - Po-Yen Chou
- Department of Veterinary Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA.,JD Wheat Veterinary Orthopedic Laboratory, School of Veterinary Medicine, University of California-Davis, Davis, CA
| | - Amy S Kapatkin
- Department of Veterinary Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA.,JD Wheat Veterinary Orthopedic Laboratory, School of Veterinary Medicine, University of California-Davis, Davis, CA
| | - Natalia Vapniarsky
- JD Wheat Veterinary Orthopedic Laboratory, School of Veterinary Medicine, University of California-Davis, Davis, CA.,Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California-Davis, Davis, CA
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Anka AU, Usman AB, Kaoje AN, Kabir RM, Bala A, Kazem Arki M, Hossein-Khannazer N, Azizi G. Potential mechanisms of some selected heavy metals in the induction of inflammation and autoimmunity. EUR J INFLAMM 2022. [DOI: 10.1177/1721727x221122719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Inflammation is a physiological event that protects tissues from infection and injury. Chronic inflammation causes immune cell over activation and sustained release of inflammatory cytokines and chemokines cause pathologic conditions including autoimmune diseases. Heavy metals exposure affects innate and adaptive immune systems through triggering inflammatory responses. It seems that extended inflammatory responses could accelerate heavy metal-induced autoimmunity. In the present review we discuss the exposure route and toxicity of Cadmium (Cd), Lead (Pb), Mercury (Hg), Vanadium (V) and Platinum (Pt) and their effects on inflammatory responses by innate and adaptive immune system and autoimmunity.
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Affiliation(s)
- Abubakar U Anka
- Department of Medical Laboratory Science, College of Medical Sciences, Ahmadu Bello University, Zaria, Nigeria
| | - Abubakar B Usman
- Department of Immunology, School of Medical Laboratory Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria
| | - Abubakar N Kaoje
- Department of Health Services, Federal University Birnin Kebbi, Birnin Kebbi, Nigeria
| | - Ramadan M Kabir
- Laboratory Department, Murtala Muhammad Specialist Hospital, Kano, Nigeria
| | - Aliyu Bala
- Hematology Department, Federal Medical Center, Katsina, Nigeria
| | - Mandana Kazem Arki
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Nikoo Hossein-Khannazer
- Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Gholamreza Azizi
- Non-Communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran
- Research Center for Immunodeficiencies, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran
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Kinbara M, Bando K, Shiraishi D, Kuroishi T, Nagai Y, Ohtsu H, Takano-Yamamoto T, Sugawara S, Endo Y. Mast cell histamine-mediated transient inflammation following exposure to nickel promotes nickel allergy in mice. Exp Dermatol 2016; 25:466-71. [PMID: 26910392 DOI: 10.1111/exd.12985] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/05/2016] [Indexed: 12/19/2022]
Abstract
We previously reported that allergic responses to nickel (Ni) were minimal in mice deficient in the histamine-forming enzyme histidine decarboxylase (HDC-KO), suggesting an involvement of histamine in allergic responses to Ni. However, it remains unclear how histamine is involved in the process of Ni allergy. Here, we examined the role of histamine in Ni allergy using a murine model previously established by us. Mice were sensitized to Ni by intraperitoneal injection of a NiCl2 -lipopolysaccharide (LPS) mixture. Ten days later, allergic inflammation was elicited by challenging ear-pinnas intradermally with NiCl2 . Then, ear-swelling was measured. Pyrilamine (histamine H1-receptor antagonist) or cromoglicate (mast cell stabilizer) was intravenously injected 1 h before the sensitization or the challenge. In cell-transfer experiments, spleen cells from Ni-sensitized donor mice were intravenously transferred into non-sensitized recipient mice. In both sensitized and non-sensitized mice, 1 mm or more NiCl2 (injected into ear-pinnas) induced transient non-allergic inflammation (Ni-TI) with accompanying mast cell degranulation. LPS did not affect the magnitude of this Ni-TI. Pyrilamine and cromoglicate reduced either the Ni-TI or the ensuing allergic inflammation when administered before Ni-TI (at either the sensitization or elicitation step), but not if administered when the Ni-TI had subsided. Experiments on HDC-KO and H1-receptor-KO mice, and also cell-transfer experiments using these mice, demonstrated histamine's involvement in both the sensitization and elicitation steps. These results suggest that mast cell histamine-mediated Ni-TI promotes subsequent allergic inflammatory responses to Ni, raising the possibility that control of Ni-TI by drugs may be effective at preventing or reducing Ni allergy.
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Affiliation(s)
- Masayuki Kinbara
- Department of Molecular Regulation, Graduate School of Dentistry, Tohoku University, Sendai, Japan.,Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Kanan Bando
- Department of Molecular Regulation, Graduate School of Dentistry, Tohoku University, Sendai, Japan.,Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Daisuke Shiraishi
- Department of Molecular Regulation, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Toshinobu Kuroishi
- Department of Molecular Regulation, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Yasuhiro Nagai
- Department of Molecular Regulation, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Hiroshi Ohtsu
- Department of Applied Quantum Medical Engineering, School of Engineering, Tohoku University, Sendai, Japan
| | - Teruko Takano-Yamamoto
- Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Shunji Sugawara
- Department of Molecular Regulation, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Yasuo Endo
- Department of Molecular Regulation, Graduate School of Dentistry, Tohoku University, Sendai, Japan
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Molecular Mechanisms of Nickel Allergy. Int J Mol Sci 2016; 17:ijms17020202. [PMID: 26848658 PMCID: PMC4783936 DOI: 10.3390/ijms17020202] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 01/29/2016] [Accepted: 01/29/2016] [Indexed: 12/28/2022] Open
Abstract
Allergic contact hypersensitivity to metals is a delayed-type allergy. Although various metals are known to produce an allergic reaction, nickel is the most frequent cause of metal allergy. Researchers have attempted to elucidate the mechanisms of metal allergy using animal models and human patients. Here, the immunological and molecular mechanisms of metal allergy are described based on the findings of previous studies, including those that were recently published. In addition, the adsorption and excretion of various metals, in particular nickel, is discussed to further understand the pathogenesis of metal allergy.
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Song Y, Salbu B, Teien HC, Sørlie Heier L, Rosseland BO, Høgåsen T, Tollefsen KE. Hepatic transcriptomic profiling reveals early toxicological mechanisms of uranium in Atlantic salmon (Salmo salar). BMC Genomics 2014; 15:694. [PMID: 25145280 PMCID: PMC4148957 DOI: 10.1186/1471-2164-15-694] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Accepted: 08/11/2014] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Uranium (U) is a naturally occurring radionuclide that has been found in the aquatic environment due to anthropogenic activities. Exposure to U may pose risk to aquatic organisms due to its radiological and chemical toxicity. The present study aimed to characterize the chemical toxicity of U in Atlantic salmon (Salmo salar) using depleted uranium (DU) as a test model. The fish were exposed to three environmentally relevant concentrations of DU (0.25, 0.5 and 1.0 mg U/L) for 48 h. Hepatic transcriptional responses were studied using microarrays in combination with quantitative real-time reverse transcription polymerase chain reaction (qPCR). Plasma variables and chromosomal damages were also studied to link transcriptional responses to potential physiological changes at higher levels. RESULTS The microarray gene expression analysis identified 847, 891 and 766 differentially expressed genes (DEGs) in the liver of salmon after 48 h exposure to 0.25, 0.5 and 1.0 mg/L DU, respectively. These DEGs were associated with known gene ontology functions such as generation of precursor metabolites and energy, carbohydrate metabolic process and cellular homeostasis. The salmon DEGs were then mapped to mammalian orthologs and subjected to protein-protein network and pathway analysis. The results showed that various toxicity pathways involved in mitochondrial functions, oxidative stress, nuclear receptor signaling, organ damage were commonly affected by all DU concentrations. Eight genes representative of several key pathways were further verified using qPCR No significant formation of micronuclei in the red blood cells or alterations of plasma stress variables were identified. CONCLUSION The current study suggested that the mitochondrion may be a key target of U chemical toxicity in salmon. The induction of oxidative stress and uncoupling of oxidative phosphorylation may be two potential modes of action (MoA) of DU. These MoAs may subsequently lead to downstream events such as apoptosis, DNA repair, hypoxia signaling and immune response. The early toxicological mechanisms of U chemical toxicity in salmon has for the first time been systematically profiled. However, no other physiological changes were observed. Future efforts to link transcriptional responses to adverse effects have been outlined as important for understanding of potential risk to aquatic organisms.
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Affiliation(s)
- You Song
- Department of Environmental Sciences (IMV), Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Centre for Environmental Radioactivity (CERAD), P,O, Box 5003, N-1432 Ås, Norway.
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Abstract
Metal hypersensitivity is a common immune disorder. Human immune systems mount the allergic attacks on metal ions through skin contacts, lung inhalation and metal-containing artificial body implants. The consequences can be simple annoyances to life-threatening systemic illness. Allergic hyper-reactivities to nickel (Ni) and beryllium (Be) are the best-studied human metal hypersensitivities. Ni-contact dermatitis affects 10 % of the human population, whereas Be compounds are the culprits of chronic Be disease (CBD). αβ T cells (T cells) play a crucial role in these hypersensitivity reactions. Metal ions work as haptens and bind to the surface of major histocompatibility complex (MHC) and peptide complex. This modifies the binding surface of MHC and triggers the immune response of T cells. Metal-specific αβ T cell receptors (TCRs) are usually MHC restricted, especially MHC class II (MHCII) restricted. Numerous models have been proposed, yet the mechanisms and molecular basis of metal hypersensitivity remain elusive. Recently, we determined the crystal structures of the Ni and Be presenting human MHCII molecules, HLA-DR52c (DRA*0101, DRB3*0301) and HLA-DP2 (DPA1*0103, DPB1*0201). These structures revealed unusual features of MHCII molecules and shed light on how metal ions are recognized by T cells.
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Kinbara M, Nagai Y, Takano-Yamamoto T, Sugawara S, Endo Y. Cross-reactivity among some metals in a murine metal allergy model. Br J Dermatol 2011; 165:1022-9. [DOI: 10.1111/j.1365-2133.2011.10468.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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10
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Kinbara M, Sato N, Kuroishi T, Takano-Yamamoto T, Sugawara S, Endo Y. Allergy-inducing nickel concentration is lowered by lipopolysaccharide at both the sensitization and elicitation steps in a murine model. Br J Dermatol 2010; 164:356-62. [DOI: 10.1111/j.1365-2133.2010.10016.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kim JY, Huh K, Lee KY, Yang JM, Kim TJ. Nickel induces secretion of IFN-gamma by splenic natural killer cells. Exp Mol Med 2009; 41:288-95. [PMID: 19299918 DOI: 10.3858/emm.2009.41.4.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Although nickel hypersensitivity is known as a delayed-type hypersensitivity mediated by nickel-specific T cells, it is greatly influenced by other immune cells. Here we show that splenic natural killer cells (NK cells) directly or indirectly respond to nickel by secretion of IFN-gamma. Using enzyme-linked immunosorbent spot (ELISPOT) assays, we found that nickel-reactive cells readily secreted IFN-gamma when splenocytes were cultured in the presence of varying concentrations of nickel sulfate (NiSO(4)) for 24 h. However, nickel-reactive IL-2- or IL- 4-secreting cells were infrequent during the 24-h culture with NiSO(4). Immune responses to nickel were innate, not adaptive, in nature since the frequency of nickel-reactive IFN-g-secreting cells did not increase upon previous exposure to NiSO(4) and recombination activating gene (RAG)-1-deficient mice contained nickel-reactive IFN-gamma-secreting cells. The involvement of NK cells in the innate response to NiSO(4) was confirmed since we could observe a significant reduction of the frequency of nickel-reactive cells in NK cell-depleted mice. Furthermore, the number of IFN-gamma secreting cells was significantly reduced in the ELISPOT assays when NKG2D was blocked by anti-NKG2D antibody. These results suggest that there is an early and rapid innate immune response to nickel, which is mediated by NK cells and the NKG2D receptor. The significance of the innate response to nickel is that it may contribute to development of the late T cell-mediated delayed type hypersensitivity against nickel.
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Affiliation(s)
- Ji Yeon Kim
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon 440-746, Korea
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Abstract
Allergic contact dermatitis (ACD) to haptens can serve as a valuable paradigm for understanding the physiopathology of T cell mediated immune responses. In sensitized individuals, exposure to the relevant hapten initiates clinical expression of ACD, which depends on the rapid activation of specific T cells. Mechanisms of tissue damage include direct cytotoxicity against keratinocytes, mostly mediated by CD8+ T cells, and T cell release of cytokines, which amplify the inflammatory response by targeting resident skin cells. The expression of ACD is actively regulated by specialized subsets of T lymphocytes with suppressive functions. In particular, T regulatory cells producing high levels of IL-10 suppress ACD by blocking the functions of dendritic cells. In contrast CD4+CD25+ regulatory T cells prevent immunopathological reactions and maintain peripheral tolerance to haptens by acting via a cell-to-cell contact mechanism. Understanding the role of suppressor T cells and the requirements for their in vivo and in vitro expansion are critical steps for the development of specific desensitization protocols in hapten-allergic individuals. This information may also provide the basis for novel interventions in other immune-mediated diseases.
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Thierse HJ, Moulon C, Allespach Y, Zimmermann B, Doetze A, Kuppig S, Wild D, Herberg F, Weltzien HU. Metal-Protein Complex-Mediated Transport and Delivery of Ni2+ to TCR/MHC Contact Sites in Nickel-Specific Human T Cell Activation. THE JOURNAL OF IMMUNOLOGY 2004; 172:1926-34. [PMID: 14734778 DOI: 10.4049/jimmunol.172.3.1926] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Nickel allergy clearly involves the activation of HLA-restricted, skin-homing, Ni-specific T cells by professional APCs. Nevertheless, knowledge concerning the molecular details of metal-protein interactions underlying the transport and delivery of metal ions to APC during the early sensitization phase and their interactions with HLA and TCRs is still fragmentary. This study investigates the role of human serum albumin (HSA), a known shuttling molecule for Ni(2+) and an often-disregarded, major component of skin, in these processes. We show that Ni-saturated HSA complexes (HSA-Ni) induce and activate Ni-specific human T cells as potently as Ni salt solutions when present at equimolar concentrations classically used for in vitro T cell stimulation. However, neither HSA itself nor its Ni-binding N-terminal peptide are involved in determining the specificity of antigenic determinants. In fact, HSA could be replaced by xenogeneic albumins exhibiting sufficient affinity for Ni(2+) as determined by surface plasmon resonance (Biacore technology) or atomic absorption spectroscopy. Moreover, despite rapid internalization of HSA-Ni by APC, it was not processed into HLA-associated epitopes recognizable by Ni-specific T cells. In contrast, the presence of HSA-Ni in the vicinity of transient contacts between TCR and APC-exposed HLA molecules appeared to facilitate a specific transfer of Ni(2+) from HSA to high-affinity coordination sites created at the TCR/HLA-interface.
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