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Event: 1495

Key Event Title

A descriptive phrase which defines a discrete biological change that can be measured. More help

Substance interaction with the lung resident cell membrane components

Short name
The KE short name should be a reasonable abbreviation of the KE title and is used in labelling this object throughout the AOP-Wiki. More help
Interaction with the lung cell membrane
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Biological Context

Structured terms, selected from a drop-down menu, are used to identify the level of biological organization for each KE. More help
Level of Biological Organization

Cell term

The location/biological environment in which the event takes place.The biological context describes the location/biological environment in which the event takes place.  For molecular/cellular events this would include the cellular context (if known), organ context, and species/life stage/sex for which the event is relevant. For tissue/organ events cellular context is not applicable.  For individual/population events, the organ context is not applicable.  Further information on Event Components and Biological Context may be viewed on the attached pdf. More help
Cell term
eukaryotic cell

Organ term

The location/biological environment in which the event takes place.The biological context describes the location/biological environment in which the event takes place.  For molecular/cellular events this would include the cellular context (if known), organ context, and species/life stage/sex for which the event is relevant. For tissue/organ events cellular context is not applicable.  For individual/population events, the organ context is not applicable.  Further information on Event Components and Biological Context may be viewed on the attached pdf. More help

Key Event Components

The KE, as defined by a set structured ontology terms consisting of a biological process, object, and action with each term originating from one of 14 biological ontologies (Ives, et al., 2017; Biological process describes dynamics of the underlying biological system (e.g., receptor signalling).Biological process describes dynamics of the underlying biological system (e.g., receptor signaling).  The biological object is the subject of the perturbation (e.g., a specific biological receptor that is activated or inhibited). Action represents the direction of perturbation of this system (generally increased or decreased; e.g., ‘decreased’ in the case of a receptor that is inhibited to indicate a decrease in the signaling by that receptor).  Note that when editing Event Components, clicking an existing Event Component from the Suggestions menu will autopopulate these fields, along with their source ID and description.  To clear any fields before submitting the event component, use the 'Clear process,' 'Clear object,' or 'Clear action' buttons.  If a desired term does not exist, a new term request may be made via Term Requests.  Event components may not be edited; to edit an event component, remove the existing event component and create a new one using the terms that you wish to add.  Further information on Event Components and Biological Context may be viewed on the attached pdf. More help
Process Object Action
pattern recognition receptor signaling pathway increased
toll-like receptor signaling pathway Toll-like receptor increased
toll-like receptor 4 signaling pathway Toll-like receptor 4 increased

Key Event Overview

AOPs Including This Key Event

All of the AOPs that are linked to this KE will automatically be listed in this subsection. This table can be particularly useful for derivation of AOP networks including the KE.Clicking on the name of the AOP will bring you to the individual page for that AOP. More help
AOP Name Role of event in AOP Point of Contact Author Status OECD Status
Substance interaction with the pulmonary cell membrane leading to pulmonary fibrosis MolecularInitiatingEvent Sabina Halappanavar (send email) Under development: Not open for comment. Do not cite WPHA/WNT Endorsed
Interaction with lung cells leads to lung cancer MolecularInitiatingEvent Penny Nymark (send email) Under development: Not open for comment. Do not cite
Interaction with lung cells leading to atherosclerosis MolecularInitiatingEvent Ulla Vogel (send email) Under development: Not open for comment. Do not cite Under Development

Taxonomic Applicability

Latin or common names of a species or broader taxonomic grouping (e.g., class, order, family) that help to define the biological applicability domain of the KE.In many cases, individual species identified in these structured fields will be those for which the strongest evidence used in constructing the AOP was available in relation to this KE. More help
Term Scientific Term Evidence Link
mouse Mus musculus High NCBI
rat Rattus norvegicus High NCBI
human Homo sapiens High NCBI

Life Stages

An indication of the the relevant life stage(s) for this KE. More help
Life stage Evidence
Adults High

Sex Applicability

An indication of the the relevant sex for this KE. More help
Term Evidence
Male High

Key Event Description

A description of the biological state being observed or measured, the biological compartment in which it is measured, and its general role in the biology should be provided. More help

The human lung consists of approximately 40 different resident cell types that play different roles during homeostasis, injury, repair and disease states (Franks et al., 2008; Luettich et al., 2021). Of these, resident airway epithelial cells, alveolar/interstitial macrophages and dendritic cells are well characterised for their ability to sense the danger upon interaction with harmful substances and relay the message to mount the necessary immune/inflammatory response. The resident macrophages are present in all tissues, and in a steady state, macrophages contribute to epithelial integrity, survey the tissue for invading pathogens or chemicals and maintain an immunosuppressive environment. Their main function is to clear the incoming irritants and microbes. They are named differently based on the tissue type and their specific functions (Kierdorf et al., 2015).

Substance interactions:

The chemicals or pathogens interact with cellular membrane to gain access to the organisms’ interior. A predominant interaction mechanism involves the recognition of innate immune response agonists by pattern recognition receptors (PRRs) present on resident cells such as epithelial and alveolar macrophages. PRRs are also present on other immune and parenchymal cells. PRRs can be activated by two classes of ligands. Pathogen associated molecular patterns (PAMPs) are microbial molecules derived from invading pathogens. PAMPs will not be discussed further as pathogens are not the focus for the AOP presented here. The other class of ligands are called danger associated molecular patterns (DAMPs) that include cellular fragments, nucleic acids, small molecules, proteins and even cytokines released from injured or dying cells (Bianchi, 2007). Most fibrogenic stressors discussed in this AOP act via DAMPs-driven PRR activation. High aspect ratio (HAR) materials such as asbestos or carbon nanotubes (CNTs) pierce the cellular membrane of epithelial cells or resident macrophages resulting in cell injury or non-programmed cellular death. Alveolar macrophages trying to engulf HAR fibres that are long and stiff undergo frustrated phagocytosis because of their inability to engulf the piercing fibres and subsequently lead to cell injury (Boyles et al., 2015; Brown et al., 2007; Donaldson K et al., 2010; Dörger et al., 2001; Mossman and Churg, 1998). The cellular debris from injured or dying cell then serves as ligands for PRRs (Nakayama, 2018), leading to cell activation. In case of pro-fibrotic insoluble particles such as silica, coal dust and nanomaterials (NMs), the particle adsorbed opsonins such as immunoglobulins, complement proteins, or serum proteins act as ligands to the receptors on the macrophage cell surface (Behzadi et al., 2017). The tissue response to these materials resembles that observed following foreign body invasion in lungs.

Toll-like receptors (TLRs) are highly conserved PRRs that are associated with fibrogenic stressors (Desai et al., 2018). Inhibition of TLR-4 is protective against bleomycin-induced fibrosis (Li et al., 2015). However, the exact role and mechanisms by which TLRs mediate lung fibrosis are yet to be uncovered and some studies have shown TLRs to be protective against lung fibrosis (Desai et al., 2018). Asbestos and silica crystals are suggested to engage scavenger receptors present on the macrophages. Mice deficient in class A scavenger macrophage receptor with collagenous structure (MARCO) are shown to induce reduced fibrogenic response following chrysotile asbestos exposure; although, the direct binding of MARCO by asbestos is not investigated in the study (Murthy et al., 2015). In case of soluble substances such as bleomycin, paraquat (Dinis-Oliveira et al., 2008) (N,N'-dimethyl-4, 4′-bipyridinium dichloride) and other soluble fibrogenic chemicals, direct damage of lung epithelial cells and resulting cellular debris or secreted cytokines (DAMPs) serve as triggers for downstream cascading pro-inflammatory events, tissue injury and fibrosis. Engagement of PRRs and consequent cell activation is observed in various organisms including flies and mammals (Denholm and Phan, 1990; Matzinger, 2002).

How It Is Measured or Detected

A description of the type(s) of measurements that can be employed to evaluate the KE and the relative level of scientific confidence in those measurements.These can range from citation of specific validated test guidelines, citation of specific methods published in the peer reviewed literature, or outlines of a general protocol or approach (e.g., a protein may be measured by ELISA). Do not provide detailed protocols. More help

Detection of DAMPs or homeostasis-altering molecular processes:

Cellular interaction with substances or particles can be measured by assessing the release of DAMPs from stressed, injured or dying cells - indicative of binding of PRRs on the cell surface. Release of DAMPs is reflective of substance interaction with resident cells and their activation, a key step in the process of inflammation.

The release of DAMPs can be measured by the techniques listed in the published literature (Nikota et al., 2017; Rabolli et al., 2014; Suwara et al., 2014).

Targeted enzyme-linked immunosorbent assays (ELISA) (routinely used and recommended):

ELISA  – permits quantitative measurement of antigens in biological samples. For example, in a cytokine ELISA (sandwich ELISA), an antibody (capture antibody) specific to a cytokine is immobilised on microtitre wells (96-well, 386-well, etc.). Experimental samples or samples containing a known amount of the specific recombinant cytokine are then reacted with the immobilised antibody. Following removal of unbound antibody by thorough washing, plates are reacted with the secondary antibody (detection antibody) that is conjugated to an enzyme such as horseradish peroxidase, which when bound, will form a sandwich with the capture antibody and the cytokine (Amsen and De Visser, 2009). The secondary antibody can be conjugated to biotin, which is then detected by addition of streptavidin linked to horseradish peroxidase. A chromogenic substrate can also be added, which is the most commonly used method. Chromogenic substrate is chemically converted by the enzyme coupled to the detection antibody, resulting in colour change. The amount of colour detected is directly proportional to the amount of cytokine in the sample that is bound to the capture antibody. The results are read using a spectrophotometer and compared to the levels of cytokine in control samples where cytokine is not expected to be secreted or to the samples containing known recombinant cytokine levels.

Interleukin (IL)-1α and -1β is activated or secreted into the cytosol following stimulus (Di Paolo and Shayakhmetov, 2016). Targeted ELISA can be used to quantify IL-1α  or IL-1β that is released in the culture supernatant of the cells exposed to toxicants, in bronchoalveolar lavage fluid and serum of exposed animals. The assay is also applicable to human serum, cerebrospinal fluid, and peritoneal fluids.

Similarly, other alarmins can also be quantified by ELISA. Western blot is another method that can be used to quantify the release of various alarmins using specific antibodies. ELISA or real-time reverse transcription-polymerase chain reaction (qRT-PCR) assays can also be used to quantify the expression of genes or proteins that are regulated by the receptor binding – e.g. downstream of TLR binding.

Frustrated phagocytosis and cellular uptake of NMs:

In vitro, interaction of NMs with the cellular membrane is investigated by assessing their uptake by lysosomes (Chen et al., 2013; Nel et al., 2009; Varela et al., 2012). Immunohistochemistry methods targeting lysosome specific proteins are regularly employed for this purpose. In co-localisation experiments, lysosomal marker Lysosomal-associated membrane protein 1 (LAMP1) antibody is used to detect particle co-localisation with lysosomes. A combination of Cytoviva hyperspectral microscope and immunolocalisation (Decan et al., 2016) or confocal microscopy to visualise co-localisation of fluorescence labelled nanoparticles with lysosomal markers have been used.

Frustrated phagocytosis is assessed using microscopic techniques such as time-lapse microscopy, backscatter electron microscopy and others (Donaldson et al., 2010; Murphy et al., 2012; Padmore et al., 2017; Pascolo et al., 2013; Schinwald et al., 2012). In addition, MIE 1668 of AOP303 notes other indirect methods for measuring frustrated phagocytosis.  

Cellular co-culture models of the pulmonary epithelium:

Complex co-culture systems, such as those containing epithelial cells and immune cells, better model the environment of the lung epithelium and can be used to study the interaction of potentially pro-fibrotic fibres and particles with resident lung cells. This type of model has been used, alongside electron microscopy, to study lung cell interactions with CNTs following 24 h in vitro exposure (Clift et al., 2014). More recently, the EpiAlveolar model, which contains primary human alveolar epithelial cells, endothelial cells, as well as fibroblasts was assessed for its ability to predict fibrosis induced by CNTs (Barasova et al., 2020). Using laser scanning, fluorescence, and enhanced darkfield microscopy, CNT interaction with the resident cells of the model was shown, and this interaction induced the formation of holes in the epithelial model (Barasova et al., 2020). While new co-culture models are a better recapitulation of the native lung environment as compared to traditional mono-cultures, the increased complexity necessitates enhanced expertise in tissue culture techniques, and can make them less practical as compared to submerged mono culture methods. 

Ex vivo model of the lung – Precision cut lung slices (PCLS):

Even closer to the in vivo condition than co-culture models, PCLS techniques capture the native lung architecture, cell-cell communication and cellularity of the lung. Advancement in culturing and cryopreservation techniques has increased accessibility and use of PCLS for longer term studies (Bai et al., 2016, Neuhaus et al., 2017). These slices can be cultured ex vivo for up to a week with minimal reduction in viability, and the technique has recently been assessed for its applicability to assess nanomaterial induced fibrosis ex vivo (Rahman et al., 2020). Using multi-walled carbon nanotubes (MWCNTs) and darkfield microscopy, interaction between the nanofibers and the lung epithelium could be determined. The main downside of this technique is the animal requirement, which precludes their use in a first-pass screening context for the MIE.

Domain of Applicability

A description of the scientific basis for the indicated domains of applicability and the WoE calls (if provided).  More help

Human, mouse, rat.

Although the expression of DAMPs following exposure to pro-fibrotic substances is not assessed across species, it is known that alarmins are released after trauma or injury, and their release is important for initiating the inflammatory response in all species including humans. The immediate acute inflammatory response involving DAMP signalling is also observed in human idiopathic pulmonary fibrosis (IPF); however, anti-inflammatory drugs have proven ineffective for treating IPF. Danger signalling axis including uric acid, adenosine triphosphate and IL-33/ST2 has been proven to promote lung fibrosis in animals.


List of the literature that was cited for this KE description. More help

1. Amsen D, de Visser KE, Town T. Approaches to determine expression of inflammatory cytokines. Methods Mol Biol. 2009;511:107-42. doi: 10.1007/978-1-59745-447-6_5.

2. Bai Y, Krishnamoorthy N, Patel KR, Rosas I, Sanderson MJ, Ai X. Cryopreserved Human Precision-Cut Lung Slices as a Bioassay for Live Tissue Banking. A Viability Study of Bronchodilation with Bitter-Taste Receptor Agonists. Am J Respir Cell Mol Biol. 2016 May;54(5):656-63. doi: 10.1165/rcmb.2015-0290MA. 

3. Barosova H, Maione AG, Septiadi D, Sharma M, Haeni L, Balog S, O'Connell O, Jackson GR, Brown D, Clippinger AJ, Hayden P, Petri-Fink A, Stone V, Rothen-Rutishauser B. Use of EpiAlveolar Lung Model to Predict Fibrotic Potential of Multiwalled Carbon Nanotubes. ACS Nano. 2020 Apr 28;14(4):3941-3956. doi: 10.1021/acsnano.9b06860. 

4. Behzadi S, Serpooshan V, Tao W, Hamaly MA, Alkawareek MY, Dreaden EC, Brown D, Alkilany AM, Farokhzad OC, Mahmoudi M. Cellular uptake of nanoparticles: journey inside the cell. Chem Soc Rev. 2017 Jul 17;46(14):4218-4244. doi: 10.1039/c6cs00636a. 

5. Bianchi ME. DAMPs, PAMPs and alarmins: all we need to know about danger. J Leukoc Biol. 2007 Jan;81(1):1-5. doi: 10.1189/jlb.0306164. 

6. Boyles MS, Young L, Brown DM, MacCalman L, Cowie H, Moisala A, Smail F, Smith PJ, Proudfoot L, Windle AH, Stone V. Multi-walled carbon nanotube induced frustrated phagocytosis, cytotoxicity and pro-inflammatory conditions in macrophages are length dependent and greater than that of asbestos. Toxicol In Vitro. 2015 Oct;29(7):1513-28. doi: 10.1016/j.tiv.2015.06.012.

7. Brown DM, Kinloch IA, Bangert U, Windle AH, Walter DM, Walker GS, et al. An in vitro study of the potential of carbon nanotubes and nanofibres to induce inflammatory mediators and frustrated phagocytosis. Carbon. 2007;45(9):1743-56. doi:

8. Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health. (2011). Current Intelligence Bulletin 62: Asbestos Fibers and Other Elongate Mineral Particles: State of the Science and Roadmap for Research. Retrieved from

9. Cheng LC, Jiang X, Wang J, Chen C, Liu RS. Nano-bio effects: interaction of nanomaterials with cells. Nanoscale. 2013 May 7;5(9):3547-69. doi: 10.1039/c3nr34276j. 

10. Clift MJ, Endes C, Vanhecke D, Wick P, Gehr P, Schins RP, Petri-Fink A, Rothen-Rutishauser B. A comparative study of different in vitro lung cell culture systems to assess the most beneficial tool for screening the potential adverse effects of carbon nanotubes. Toxicol Sci. 2014 Jan;137(1):55-64. doi: 10.1093/toxsci/kft216. 

11. Decan N, Wu D, Williams A, Bernatchez S, Johnston M, Hill M, Halappanavar S. Characterization of in vitro genotoxic, cytotoxic and transcriptomic responses following exposures to amorphous silica of different sizes. Mutat Res Genet Toxicol Environ Mutagen. 2016 Jan 15;796:8-22. doi: 10.1016/j.mrgentox.2015.11.011.

12. Denholm EM, Phan SH. Bleomycin binding sites on alveolar macrophages. J Leukoc Biol. 1990 Dec;48(6):519-23. doi: 10.1002/jlb.48.6.519.

13. Desai O, Winkler J, Minasyan M, Herzog EL. The Role of Immune and Inflammatory Cells in Idiopathic Pulmonary Fibrosis. Front Med (Lausanne). 2018 Mar 20;5:43. doi: 10.3389/fmed.2018.00043. 

14. Di Paolo NC, Shayakhmetov DM. Interleukin 1α and the inflammatory process. Nat Immunol. 2016 Jul 19;17(8):906-13. doi: 10.1038/ni.3503.

15. Dinis-Oliveira RJ, Duarte JA, Sánchez-Navarro A, Remião F, Bastos ML, Carvalho F. Paraquat poisonings: mechanisms of lung toxicity, clinical features, and treatment. Crit Rev Toxicol. 2008;38(1):13-71. doi: 10.1080/10408440701669959.

16. Donaldson K, Murphy FA, Duffin R, Poland CA. Asbestos, carbon nanotubes and the pleural mesothelium: a review of the hypothesis regarding the role of long fibre retention in the parietal pleura, inflammation and mesothelioma. Part Fibre Toxicol. 2010 Mar 22;7:5. doi: 10.1186/1743-8977-7-5.

17. Dörger M, Münzing S, Allmeling AM, Messmer K, Krombach F. Differential responses of rat alveolar and peritoneal macrophages to man-made vitreous fibers in vitro. Environ Res. 2001 Mar;85(3):207-14. doi: 10.1006/enrs.2001.4234.

18. Franks TJ, Colby TV, Travis WD, Tuder RM, Reynolds HY, Brody AR, Cardoso WV, Crystal RG, Drake CJ, Engelhardt J, Frid M, Herzog E, Mason R, Phan SH, Randell SH, Rose MC, Stevens T, Serge J, Sunday ME, Voynow JA, Weinstein BM, Whitsett J, Williams MC. Resident cellular components of the human lung: current knowledge and goals for research on cell phenotyping and function. Proc Am Thorac Soc. 2008 Sep 15;5(7):763-6. doi: 10.1513/pats.200803-025HR.

19. Kierdorf K, Prinz M, Geissmann F, Gomez Perdiguero E. Development and function of tissue resident macrophages in mice. Semin Immunol. 2015 Dec;27(6):369-78. doi: 10.1016/j.smim.2016.03.017.

20. Kim JE, Lim HT, Minai-Tehrani A, Kwon JT, Shin JY, Woo CG, Choi M, Baek J, Jeong DH, Ha YC, Chae CH, Song KS, Ahn KH, Lee JH, Sung HJ, Yu IJ, Beck GR Jr, Cho MH. Toxicity and clearance of intratracheally administered multiwalled carbon nanotubes from murine lung. J Toxicol Environ Health A. 2010;73(21-22):1530-43. doi: 10.1080/15287394.2010.511578. 

21. Luettich K, Sharma M, Yepiskoposyan H, Breheny D, Lowe FJ. An Adverse Outcome Pathway for Decreased Lung Function Focusing on Mechanisms of Impaired Mucociliary Clearance Following Inhalation Exposure. Front Toxicol. 2021 Dec 14;3:750254. doi: 10.3389/ftox.2021.750254.

22. Li XX, Jiang DY, Huang XX, Guo SL, Yuan W, Dai HP. Toll-like receptor 4 promotes fibrosis in bleomycin-induced lung injury in mice. Genet Mol Res. 2015 Dec 21;14(4):17391-8. doi: 10.4238/2015.

23. Matzinger P. The danger model: a renewed sense of self. Science. 2002 Apr 12;296(5566):301-5. doi: 10.1126/science.1071059.

24. Mossman BT, Churg A. Mechanisms in the pathogenesis of asbestosis and silicosis. Am J Respir Crit Care Med. 1998 May;157(5 Pt 1):1666-80. doi: 10.1164/ajrccm.157.5.9707141.

25. Murphy FA, Schinwald A, Poland CA, Donaldson K. The mechanism of pleural inflammation by long carbon nanotubes: interaction of long fibres with macrophages stimulates them to amplify pro-inflammatory responses in mesothelial cells. Part Fibre Toxicol. 2012 Apr 3;9:8. doi: 10.1186/1743-8977-9-8. 

26. Murthy S, Larson-Casey JL, Ryan AJ, He C, Kobzik L, Carter AB. Alternative activation of macrophages and pulmonary fibrosis are modulated by scavenger receptor, macrophage receptor with collagenous structure. FASEB J. 2015 Aug;29(8):3527-36. doi: 10.1096/fj.15-271304.

27. Nakayama M. Macrophage Recognition of Crystals and Nanoparticles. Front Immunol. 2018 Jan 29;9:103. doi: 10.3389/fimmu.2018.00103. 

28. Nel AE, Mädler L, Velegol D, Xia T, Hoek EM, Somasundaran P, Klaessig F, Castranova V, Thompson M. Understanding biophysicochemical interactions at the nano-bio interface. Nat Mater. 2009 Jul;8(7):543-57. doi: 10.1038/nmat2442. 

29. Neuhaus V, Schaudien D, Golovina T, Temann UA, Thompson C, Lippmann T, Bersch C, Pfennig O, Jonigk D, Braubach P, Fieguth HG, Warnecke G, Yusibov V, Sewald K, Braun A. Assessment of long-term cultivated human precision-cut lung slices as an ex vivo system for evaluation of chronic cytotoxicity and functionality. J Occup Med Toxicol. 2017 May 26;12:13. doi: 10.1186/s12995-017-0158-5.

30. Nikota J, Banville A, Goodwin LR, Wu D, Williams A, Yauk CL, Wallin H, Vogel U, Halappanavar S. Stat-6 signaling pathway and not Interleukin-1 mediates multi-walled carbon nanotube-induced lung fibrosis in mice: insights from an adverse outcome pathway framework. Part Fibre Toxicol. 2017 Sep 13;14(1):37. doi: 10.1186/s12989-017-0218-0.

31. Padmore T, Stark C, Turkevich LA, Champion JA. Quantitative analysis of the role of fiber length on phagocytosis and inflammatory response by alveolar macrophages. Biochim Biophys Acta Gen Subj. 2017 Feb;1861(2):58-67. doi: 10.1016/j.bbagen.2016.09.031.

32. Pascolo L, Gianoncelli A, Schneider G, Salomé M, Schneider M, Calligaro C, Kiskinova M, Melato M, Rizzardi C. The interaction of asbestos and iron in lung tissue revealed by synchrotron-based scanning X-ray microscopy. Sci Rep. 2013;3:1123. doi: 10.1038/srep01123. 

33. Poland CA, Duffin R, Kinloch I, Maynard A, Wallace WA, Seaton A, Stone V, Brown S, Macnee W, Donaldson K. Carbon nanotubes introduced into the abdominal cavity of mice show asbestos-like pathogenicity in a pilot study. Nat Nanotechnol. 2008 Jul;3(7):423-8. doi: 10.1038/nnano.2008.111.

34. Rabolli V, Badissi AA, Devosse R, Uwambayinema F, Yakoub Y, Palmai-Pallag M, Lebrun A, De Gussem V, Couillin I, Ryffel B, Marbaix E, Lison D, Huaux F. The alarmin IL-1α is a master cytokine in acute lung inflammation induced by silica micro- and nanoparticles. Part Fibre Toxicol. 2014 Dec 13;11:69. doi: 10.1186/s12989-014-0069-x.

35. Rahman L, Williams A, Gelda K, Nikota J, Wu D, Vogel U, Halappanavar S. 21st Century Tools for Nanotoxicology: Transcriptomic Biomarker Panel and Precision-Cut Lung Slice Organ Mimic System for the Assessment of Nanomaterial-Induced Lung Fibrosis. Small. 2020 Sep;16(36):e2000272. doi: 10.1002/smll.202000272.

36. Schinwald A, Donaldson K. Use of back-scatter electron signals to visualise cell/nanowires interactions in vitro and in vivo; frustrated phagocytosis of long fibres in macrophages and compartmentalisation in mesothelial cells in vivo. Part Fibre Toxicol. 2012 Aug 28;9:34. doi: 10.1186/1743-8977-9-34. 

37. Suwara MI, Green NJ, Borthwick LA, Mann J, Mayer-Barber KD, Barron L, Corris PA, Farrow SN, Wynn TA, Fisher AJ, Mann DA. IL-1α released from damaged epithelial cells is sufficient and essential to trigger inflammatory responses in human lung fibroblasts. Mucosal Immunol. 2014 May;7(3):684-93. doi: 10.1038/mi.2013.87.

38. Varela JA, Bexiga MG, Åberg C, Simpson JC, Dawson KA. Quantifying size-dependent interactions between fluorescently labeled polystyrene nanoparticles and mammalian cells. J Nanobiotechnology. 2012 Sep 24;10:39. doi: 10.1186/1477-3155-10-39.