- Please check and comment entries here.
Antigenic essence – the part of a cell that is both available to the immune system and also highly specific to cell type on a molecular profile level. Antigenic essence can be collected from the cell surface by treating living cells with protease (trypsin) under mild conditions. Cells are a natural source for the entire diversity of native antigens including for anticancer vaccination. Antigenic essence takes advantage of this while also minimizing the limitations associated with the use of whole cells for anticancer vaccination.
Cellular cancer vaccines are among the first types of cancer vaccines to be tested . They use a straightforward approach based on the well-known principle of vaccination: vaccinate with what you want to develop protection against. Cancer cells are typically irradiated, combined with an immunostimulatory adjuvant, and then administered to the patient, usually from whom the tumor cells were isolated . Such vaccines have undergone extensive scientific research and have been widely tested in various cancers, including lung cancer , colorectal cancer , melanoma , renal cell cancer , and prostate cancer . The significant possibilities of such vaccines have been described, but none have yet passed the clinical trial stage. It can be argued that antigenic essence technology is the revitalization of cellular vaccination, as antigenic essence exhibits all the identifying properties of cancer cells while also allowing for control of composition, purification from ballast substances ("cellular noise"), and evasion of MHC restrictions. Therefore, antigenic essence technology allows for the application of already discovered cellular compositions, while overcoming their limitations.
2. Antigenic Essence Concept
The first assumption of antigenic essence is that only antigens presented on the surface of the cell are targets for vaccination, while those presented inside the cell can and should be neglected. This is based on the fact that only antigens on the cell surface are available to the immune system; the plasma membrane of living cells is impermeable to cytotoxic elements of the immune system that recognize antigens, be they antibodies or T lymphocytes. This does not contradict the fact that some intracellular antigens can be presented by MHC on the cell surface and offer suitable targets for vaccination; indeed, some such antigens are currently undergoing clinical trials. On the other hand, extracellular antigens are produced inside cells and can therefore always be found there as well. The point is not where the antigens can be found, but that they function as targets for the immune system only when presented on the cell surface. That is, the target pool of antigens is located precisely on the cell surface, and they form an actual profile of the antigenic properties of living cells.
Given that the target pool of antigens is presented on the cell surface and the cell wall is impermeable to macromolecules, the second assumption of antigenic essence is that the target pool of antigens can be collected by treating living cells with protease (Figure 1). Despite the apparent simplicity of this approach, this is not a trivial process, and the implementation in mammalian cells became possible only with advances in proteomics. When a highly purified protease is used, cytolytic activity is low , thus allowing the treatment of live cells without violating the permeability of their membranes. The use of proteomics-grade protease makes it possible to obtain just the pool of antigens from the cell surface without contamination by intracellular content. Furthermore, the obtained antigens are not overridden by impurities or autolytic fragments of the protease itself . Last but not least, the obtained antigens can be analyzed by mass spectrometry to establish essence composition, and this information can be used to fine-tune the design of cancer vaccines and validate their quality.
3. Antigenic Essence Equivalence to Cell Antigens
To confirm that antigenic essence retains the antigenic properties of live cells, its cytotoxic properties were compared with those of whole cells. In cytotoxicity assays, target human adenocarcinoma cells (MCF-7) were incubated with human cytotoxic T lymphocytes (CTLs) stimulated with antigen-presenting cells (APCs) loaded with either essence or whole cancer cell lysate. The essence was 10–40% more effective at killing target cells than the whole-cell lysate. This was accomplished using less than 1% of the total amount of protein (2 μg/mL of essence vs. 270 μg/mL of whole-cell lysate) . The complete retention of cytotoxicity combined with a dramatic reduction in protein used indicates that the essence is free from superfluous intracellular content and preserves all the antigenic properties required for targeting by the immune response. These results, together with a similar result reported for non-cancer cells in another study , confirmed the conceptual assumption that proteolytic treatment of living cells allows the collection of a complete set of antigenic targets; that is, the antigenic essence of cells.
4. Control of Antigenic Essence Composition
Antigenic essence is a product of cell culture technology, which involves a high probability of misidentification and cross-contamination between cells . Moreover, cultured mammalian cells have a finite lifespan  and are subject to progressive degeneration, which is manifested in part by changes in the molecular composition of the cell surface . Accordingly, cultivated cells intended for therapy must be authenticated and the composition of their antigenic essence validated to exclude unwanted changes in their composition.
The proven method for analysis and control of essence composition is mass spectrometry. This method is known as a proteomic footprint and represents a proteomics method for both the authentication and characterization of cells at the subtype level  as well as analysis of essence composition. By comparing the mass spectrum of the essence with that of the reference cells, the origin of the essence can be easily authenticated and its composition verified for vaccination (Figure 2). Moreover, discrepancies in this comparison would reveal any changes in antigen composition that may have occurred.
5. Antigens Size in Essence and MHC Restriction
CTLs are specialized and effective elements of the anti-tumor immune response. CTLs directly lyse target cells and also secrete cytokines (e.g., granulocyte-macrophage colony-stimulating factor, tumor necrosis factor, and interferon-gamma), which further amplify immune reactivity against target cells . It is well established that CTLs recognize antigens in the form of small peptides. Native whole antigens are internalized and proteolyzed by APCs, and then short peptides are presented to CTLs on the APC surface with MHC (8–12 amino acid residues in length for MHC class I, and 11–30 residues in length for MHC class II) .
From this point, the antigenic essence compositions are ideally suited for presentation to CTLs by MHC. While MHC class I peptides contain on average 10 residues, proteins have in their sequence an average of one trypsin cleavage site per 10 residues. This coincidence is not accidental: antigenic essence arose from proteomics technologies, in which protein cleavage with trypsin is used to produce specific peptide fragments for protein identification (known as peptide fingerprinting). Smaller fragment sizes (i.e., less than 10 residues) result in less specificity. MHC class I likely presents peptides of a similar size because they are optimal for identification. These common fundamentals of proteomics and immunology have supported the design and production of antigenic essence products, in which protein cleavage with trypsin plays a central role. Notably, partial cleavage of proteins by trypsin produces larger peptides, which are also included in the antigenic essence and well-suited for presentation by MHC class II.
6. Antigenic Essence Composition and MHC Mediated Immunogenicity
To date, tumor antigens successfully presented to CTLs have been identified by various methods . In most cases, CTLs derived from cancer patients were used to screen either expression gene libraries or peptides eluted from tumor cell MHC molecules. Most of these CTLs were derived from patients with a particular tumor, and as a result, the majority of defined antigens were restricted to this tumor indication. Later, an alternative approach was developed that did not require the use of patient CTLs, but instead relied on the identification of MHC-binding peptides and on novel in vitro priming protocols . Specifically, peptides selected for their binding capacity to MHC molecules were tested for their ability to elicit tumor-reactive CTLs in vitro using lymphocyte cultures from normal individuals. Following this approach, several TAAs presented to CTLs were identified for melanoma tumors . Furthermore, this approach was successfully used to identify antigens expressed in solid adenocarcinomas (including MAGE2, MAGE3, carcinoembryonic antigen (CEA), and HER-2/neu) . These results are relevant for the development of epitope-based immunotherapy of high-incidence tumors such as breast, lung, colon, and gastric carcinomas . In vitro priming of CTLs from normal individuals is a useful tool for the development of dendritic cell vaccines. Such an approach has been used in an in vitro study of dendritic cells (DCs) ability to present antigens to CTLs, a process in which MHC is directly involved.
This DC vaccine development routine (combined with cell footprinting data) is an essential part of essence vaccine development (Figure 3). DCs presented essence antigens to CTLs through MHC. The target cell killing rate by activated CTLs is reflected in equation describing antigenic essence efficacy: N = k * r + b.
In this equation, N is the number of total viable target cells in cytotoxicity assays (representing the inverse of CTL cytotoxicity), k and b represent a contribution to the immune response independent of essence/target similarity (i.e., r value). This contribution is referred to as antigenic essence immunogenicity influenced by MHC restriction. In the final antigenic essence compositions, these parameters should be fine-tuned to strike a balance in essence/target similarity and essence immunogenicity.
7. Antigenic Essence and Immunopeptidome
In the light of the concept of antigenic essence, mention should be made of immunopeptidome: peptides associated with MHC. Immunopeptidome is produced by the proteasome degradation of intracellular proteins. Immunopeptidome analysis has become one of the essential directions of working with adaptive immunity and facilitates the development of personalized cancer vaccines. Although the antigenic essence has not been studied for enrichment with peptides from immunopeptidome, a significant fraction of it is probably included in essence. Although the main method for obtaining immunopeptidome is elution of peptides from MHC molecules , it is known that soluble MHC fragments with peptide ligands circulate in the bloodstream , which is the result of MHC cleavage by various proteases . Moreover, to obtain such MHC fragments, the protease (papain) was used to treat living cells , after which peptides from the immunopeptide released with MHC fragments were identified . The similarity of this approach with the production of antigenic essence indicates a possible enrichment of the antigenic essence with peptides from the immunopeptide, which means enrichment with intracellular antigens relevant for vaccination. However, the degree of such enrichment requires further research.
8. Upgrade of Developed Cellular Cancer Vaccines
Developed to date classical cancer vaccines, which operate on the principle that you should vaccinate with what you want to develop protection against, include whole-cell formulations. Such vaccines have been widely tested in various cancers and their advantages are described but such vaccines have not passed clinical trials due to lack of effectiveness. Antigenic essence technology offers the possibility to revitalize the field of whole-cell-based vaccination. In such vaccines, whole cells just may be replaced by antigenic essence obtained from the same cancer cells.
In addition to all the advantages described above that antigenic essence gives during vaccination, some other advantages of such upgrade of vaccines should be mentioned. Since antigenic essence is acellular formulation, such upgraded vaccines will have undeniable advantages concerning safety. They are free of any cells and supramolecular formations. The production process excludes the presence of bacteria, viruses, protozoa, as well as prions and other foreign proteins (e.g., bovine proteins from the culture medium). Thus, they are less likely to cause infection or allergic reactions. This aligns with current guidance regarding the development of new cancer vaccines with enhanced safety and tolerability profiles  and simplifies the implementation of Food and Drug Administration (FDA) requirements . The absence of side effects will significantly reduce the door-to-needle time, which is extremely important for mass vaccination and has been a significant limiting and price-forming factor of cellular vaccines.
A significant simplification in the transportation and storage of upgraded vaccines is expected in comparison with their cellular analogs. Storage and transportation of cell preparations are usually carried out in liquid nitrogen with cryoprotectant, which is labor-intensive, and the defrosting of cells is typically associated with massive cell lysis. Antigenic essence, being a peptide preparation, requires ultra-low temperatures only during long-term storage , and in general, can be frozen normally or, as a lyophilizate, stored at low temperatures (+4–8 °C) and transported at room temperature.
Radical simplification in transportation and storage, increased safety, and decreased door-to-needle time will undoubtedly lead to a radical reduction in the cost of upgraded vaccines. The cost of upgraded vaccines will also be affected by the near-absence of cellular material consumption during their production. A single set of cells can be reused to generate multiple batches of antigenic essence due to the regeneration of cells after treatment with protease . Thus, virtually any dose can be generated without wasting cellular material, which is important for the mass production of affordable cancer vaccines. A notable exception to this is perhaps in upgraded vaccines obtained from primary cultures where long-term cultivation of cells without degeneration of their molecular phenotype is impossible.
This entry is adapted from 10.3390/cancers13040774
- M. G. Hanna; L. C. Peters; Specific immunotherapy of established visceral micrometastases by BCG-tumor cell vaccine alone or as an adjunct to surgery. Cancer 1978, 42, 2613-2625, .
- Milton Berger; Fernando T Kreutz; Jorge L Horst; Aline C Baldi; Walter J Koff; Phase I study with an autologous tumor cell vaccine for locally advanced or metastatic prostate cancer. Journal of Pharmacy & Pharmaceutical Sciences 2007, 10, 144–152, .
- Jules E. Harris; Louise Ryan; Herbert C. Hoover Jr; Robert K. Stuart; Martin M. Oken; Al B. Benson; Edward Mansour; Daniel G. Haller; Judith Manola; Michael G. Hanna Jr; et al. Adjuvant Active Specific Immunotherapy for Stage II and III Colon Cancer With an Autologous Tumor Cell Vaccine: Eastern Cooperative Oncology Group Study E5283. Journal of Clinical Oncology 2000, 18, 148-148, .
- C Maver; M McKneally; Preparation of autologous tumor cell vaccine from human lung cancer. Cancer Research 1979, 39, 3276, .
- R S Schulof; D Mai; M A Nelson; H M Paxton; J W Cox; M L Turner; M Mills; W R Hix; L E Nochomovitz; L C Peters; et al. Active specific immunotherapy with an autologous tumor cell vaccine in patients with resected non-small cell lung cancer. Molecular biotherapy 1988, 1, 30–36, .
- John Nemunaitis; Daniel Sterman; David Jablons; John W. Smith; Bernard Fox; Phil Maples; Scott Hamilton; Flavia Borellini; Andy Lin; Sayeh Morali; et al. Granulocyte-Macrophage Colony-Stimulating Factor Gene-Modified Autologous Tumor Vaccines in Non-Small-Cell Lung Cancer. Journal of the National Cancer Institute 2004, 96, 326-331, .
- Dominik Rüttinger; Natasja K Van Den Engel; Hauke Winter; Marcus Schlemmer; Heike Pohla; Stefanie Grützner; Beate Wagner; Dolores J Schendel; Bernard A Fox; K-W Jauch; et al. Adjuvant therapeutic vaccination in patients with non-small cell lung cancer made lymphopenic and reconstituted with autologous PBMC: first clinical experience and evidence of an immune response. Journal of Translational Medicine 2007, 5, 43, .
- Vincent A. De Weger; Annelies W. Turksma; Quirinus J.M. Voorham; Zelda Euler; Herman Bril; Alfons J. Van Den Eertwegh; Elisabeth Bloemena; Herbert M. Pinedo; Jan B. Vermorken; Harm Van Tinteren; et al. Clinical Effects of Adjuvant Active Specific Immunotherapy Differ between Patients with Microsatellite-Stable and Microsatellite-Instable Colon Cancer. Clinical Cancer Research 2012, 18, 882-889, .
- Michael G. Hanna; Herbert C. Hoover; Jan B. Vermorken; Jules E. Harris; Herbert M. Pinedo; Adjuvant active specific immunotherapy of stage II and stage III colon cancer with an autologous tumor cell vaccine: first randomized phase III trials show promise. Vaccine 2001, 19, 2576-2582, .
- D Ockert; V Schirrmacher; N Beck; E Stoelben; T Ahlert; J Flechtenmacher; E Hagmüller; R Buchcik; M Nagel; H D Saeger; et al. Newcastle disease virus-infected intact autologous tumor cell vaccine for adjuvant active specific immunotherapy of resected colorectal carcinoma.. Clinical Cancer Research 1996, 2, 21–28, .
- A Baars; J M G H Van Riel; M A Cuesta; E H Jaspars; H M Pinedo; A J M Van Den Eertwegh; Metastasectomy and active specific immunotherapy for a large single melanoma metastasis. Hepatogastroenterology 2002, 49, 691–693, .
- D Berd; H C Maguire; P McCue; M J Mastrangelo; Treatment of metastatic melanoma with an autologous tumor-cell vaccine: clinical and immunologic results in 64 patients.. Journal of Clinical Oncology 1990, 8, 1858-1867, .
- Rosa Méndez; Francisco Ruiz-Cabello; Teresa Rodríguez; Ana Del Campo; Annette Paschen; Dirk Schadendorf; Federico Garrido; Identification of different tumor escape mechanisms in several metastases from a melanoma patient undergoing immunotherapy. Cancer Immunology, Immunotherapy 2007, 56, 88-94, .
- Scott J Antonia; John Seigne; Jose Diaz; Carlos Muro-Cacho; Martine Extermann; Mary Jane Farmelo; Maria Friberg; Marwan Alsarraj; J J Mahany; Julio Pow-Sang; et al. Phase I trial of a B7-1 (CD80) gene modified autologous tumor cell vaccine in combination with systemic interleukin-2 in patients with metastatic renal cell carcinoma. Journal of Urology 2002, 167, 1995–2000, .
- Mayer Fishman; Terri B. Hunter; Hatem Soliman; Patricia Thompson; Mary Dunn; Renee Smilee; Mary Jane Farmelo; David R. Noyes; John J. Mahany; Ji-Hyun Lee; et al. Phase II Trial of B7-1 (CD-86) Transduced, Cultured Autologous Tumor Cell Vaccine Plus Subcutaneous Interleukin-2 for Treatment of Stage IV Renal Cell Carcinoma. Journal of Immunotherapy 2008, 31, 72-80, .
- Y Kinoshita; T Kono; R Yasumoto; T Kishimoto; C Y Wang; G P Haas; N Nishisaka; Antitumor effect on murine renal cell carcinoma by autologous tumor vaccines genetically modified with granulocyte-macrophage colony-stimulating factor and interleukin-6 cells.. Journal of Immunotherapy 2001, 24, 205–211, .
- Petr G. Lokhov; Elena E. Balashova; Cellular Cancer Vaccines: an Update on the Development of Vaccines Generated from Cell Surface Antigens. Journal of Cancer 2010, 1, 230-241, .
- Elena E Balashova; Petr G. Lokhov; Proteolytically-cleaved Fragments of Cell-surface Proteins from Live Tumor Cells Stimulate Anti-tumor Immune Response In vitro. Journal of Carcinogenesis & Mutagenesis 2010, 1, 1-3, .
- Elena E. Balashova; Petr G. Lokhov; Proteolytically-cleaved Fragments of Cell Surface Proteins Stimulate a Cytotoxic Immune Response Against Tumoractivated Endothelial Cells In vitro. Journal of Cancer Science & Therapy 2010, 2, 126-131, .
- Lokhov, P.G. Method for Producing An Antitumoral Vaccine Based on Surface Endothelial Cell Antigens. U.S. Patent Application No. 9844586, 19 December 2007
- G. N. Stacey; Cell contamination leads to inaccurate data: we must take action now. Nature 2000, 403, 356-356, .
- Roderick A.F. MacLeod; Wilhelm G. Dirks; Yoshinobu Matsuo; Maren Kaufmann; Herbert Milch; Hans G. Drexler; Widespread intraspecies cross-contamination of human tumor cell lines arising at source. International Journal of Cancer 1999, 83, 555-563, .
- Editoral.; Identity crisis. Nature 2009, 457, 935-936, .
- C. M. Cabrera; F. Cobo; A. Nieto; J. L. Cortes; R. M. Montes; Purificación Catalina; A. Concha; Identity tests: determination of cell line cross-contamination. Cytotechnology 2006, 51, 45-50, .
- L. Hayflick; P.S. Moorhead; The serial cultivation of human diploid cell strains. Experimental Cell Research 1961, 25, 585-621, .
- Woodring E. Wright; Jerry W. Shay; Historical claims and current interpretations of replicative aging. Nature Biotechnology 2002, 20, 682-688, .
- John W. Huggins; Robert W. Chestnut; Norman N. Durham; Kermit L. Carraway; Molecular changes in cell surface membranes resulting from trypsinization of sarcoma 180 tumor cells. Biochimica et Biophysica Acta (BBA) - Biomembranes 1976, 426, 630-637, .
- Rachel Angus; C.M.P. Collins; M.O. Symes; Expression of major histocompatibility complex (MHC) antigens and their loss on culture in renal carcinoma. European Journal of Cancer 1993, 29, 2158-2160, .
- Petr Lokhov; Elena Balashova; Maxim Dashtiev; Cell proteomic footprint. Rapid Communications in Mass Spectrometry 2009, 23, 680-682, .
- Nabholz, M.; MacDonald, H.R.; Cytolytic T Lymphocytes. Annu. Rev. Immunol. 1983, 1, 273, .
- A Lanzavecchia; Identifying strategies for immune intervention. Science 1993, 260, 937-944, .
- Gideon Berke; The Binding and Lysis of Target Cells by Cytotoxic Lymphocytes: Molecular and Cellular Aspects. Annual Review of Immunology 1994, 12, 735-773, .
- Ryan J. Malonis; Jonathan R. Lai; Olivia Vergnolle; Peptide-Based Vaccines: Current Progress and Future Challenges. Chemical Reviews 2019, 120, 3210-3229, .
- B J Van Den Eynde; T Boon; Tumor antigens recognized by T lymphocytes. International Journal of Clinical & Laboratory Research 1997, 27, 267–268, .
- Steven A. Rosenberg; Cancer vaccines based on the identification of genes encoding cancer regression antigens. Immunology Today 1997, 18, 175-182, .
- B Fisk; T L Blevins; J T Wharton; C G Ioannides; Identification of an immunodominant peptide of HER-2/neu protooncogene recognized by ovarian tumor-specific cytotoxic T lymphocyte lines.. Journal of Experimental Medicine 1995, 181, 2109-2117, .
- G. E. Peoples; P. S. Goedegebuure; R. Smith; D. C. Linehan; I. Yoshino; T. J. Eberlein; Breast and ovarian cancer-specific cytotoxic T lymphocytes recognize the same HER2/neu-derived peptide.. Proceedings of the National Academy of Sciences 1995, 92, 432-436, .
- A. Cox; J Skipper; Y Chen; R. Henderson; T. Darrow; J Shabanowitz; V. Engelhard; D. Hunt; C. Slingluff; Identification of a peptide recognized by five melanoma-specific human cytotoxic T cell lines. Science 1994, 264, 716-719, .
- Pierre G. Coulie; Benoît J. Van Den Eynde; Pierre Van Der Bruggen; Thierry Boon-Falleur; Tumour antigens recognized by T lymphocytes: at the core of cancer immunotherapy. Nature Cancer 2014, 14, 135-146, .
- E Celis; A Sette; H M Grey; Epitope selection and development of peptide based vaccines to treat cancer.. Seminars in Cancer Biology 1995, 6, 329, .
- E Appella; D J Loftus; K Sakaguchi; A Sette; E Celis; Synthetic antigenic peptides as a new strategy for immunotherapy of cancer. Biomedical peptides, proteins & nucleic acids : structure, synthesis & biological activity 1995, 1, 177, .
- Esteban Celis; John Fikes; Peggy Wentworth; John Sidney; Scott Southwood; Ajesh Maewal; Marie-France Del Guercio; Alessandro Sette; Brian Livingston; Identification of potential CTL epitopes of tumor-associated antigen MAGE-1 for five common HLA-A alleles. Molecular Immunology 1994, 31, 1423-1430, .
- V Tsai; S Southwood; J Sidney; Kazuyasu Sakaguchi; Y Kawakami; E Appella; A Sette; E Celis; Identification of subdominant CTL epitopes of the GP100 melanoma-associated tumor antigen by primary in vitro immunization with peptide-pulsed dendritic cells. The Journal of Immunology 1997, 158, 1796, .
- E. Celis; V. Tsai; C. Crimi; R. DeMars; P. A. Wentworth; R. W. Chesnut; H. M. Grey; A. Sette; H. M. Serra; Induction of anti-tumor cytotoxic T lymphocytes in normal humans using primary cultures and synthetic peptide epitopes.. Proceedings of the National Academy of Sciences 1994, 91, 2105-2109, .
- P Weynants; B Lethé; F Brasseur; M Marchand; T Boon; Expression of mage genes by non-small-cell lung carcinomas. International Journal of Cancer 1994, 56, 826, .
- R. G. Vincent; T. M. Chu; T. B. Fergen; M. Ostrander; Carcinoembryonic antigen in 228 patients with carcinoma of the lung. Cancer 2010, 36, 2069-2076, .
- D J Slamon; W Godolphin; L A Jones; J A Holt; S G Wong; D E Keith; W J Levin; S G Stuart; J Udove; A Ullrich; et al. Studies of the HER-2/neu proto-oncogene in human breast and ovarian cancer. Science 1989, 244, 707-712, .
- Ichiro Kawashima; Stephen J Hudson; Van Tsai; Scott Southwood; Kazutoh Takesako; Ettore Appella; Alessandro Sette; Esteban Celis; The Multi-epitope Approach for Immunotherapy for Cancer: Identification of Several CTL Epitopes from Various Tumor-Associated Antigens Expressed on Solid Epithelial Tumors. Human Immunology 1998, 59, 1-14, .
- Shunji Sugawara; Toru Abo; Katsuo Kumagai; A simple method to eliminate the antigenicity of surface class I MHC molecules from the membrane of viable cells by acid treatment at pH 3. Journal of Immunological Methods 1987, 100, 83-90, .
- M. Bassani-Sternberg; E. Barnea; I. Beer; I. Avivi; T. Katz; A. Admon; Soluble plasma HLA peptidome as a potential source for cancer biomarkers. Proceedings of the National Academy of Sciences 2010, 107, 18769-18776, .
- S. Demaria; R. Schwab; S.R. Gottesman; Y. Bushkin; Soluble beta 2-microglobulin-free class I heavy chains are released from the surface of activated and leukemia cells by a metalloprotease.. Journal of Biological Chemistry 1994, 269, 6689-6694, .
- Sandra Demaria; Yuri Bushkin; Soluble HLA proteins with bound peptides are released from the cell surface by the membrane metalloproteinase. Human Immunology 2000, 61, 1332-1338, .
- Giacomo Galati; Cinzia Arcelloni; Rita Paroni; Silvia Heltai; Patrizia Rovere; Claudio Rugarli; Angelo A. Manfredi; Quantitative cytometry of MHC class I digestion from living cells. Cytometry 1997, 27, 77-83, .
- Kwasi Antwi; Paul D. Hanavan; Cheryl E. Myers; Yvette W. Ruiz; Eric J. Thompson; Douglas F. Lake; Proteomic identification of an MHC-binding peptidome from pancreas and breast cancer cell lines. Molecular Immunology 2009, 46, 2931-2937, .
- Alex Kudrin; Overview of cancer vaccines. Human Vaccines & Immunotherapeutics 2012, 8, 1335-1353, .
- [Experts]; Guidance for Industry Clinical Considerations for Therapeutic Cancer Vaccines. Biotechnology Law Report 2012, 31, 303-309, .
- Andrew N. Hoofnagle; Jeffrey R. Whiteaker; Steven A. Carr; Eric Kuhn; Tao Liu; Sam A. Massoni; Stefani N. Thomas; Raymond R Townsend; Lisa J. Zimmerman; Emily S Boja; et al. Recommendations for the Generation, Quantification, Storage, and Handling of Peptides Used for Mass Spectrometry–Based Assays. Clinical Chemistry 2016, 62, 48-69, .
- Hsiang-Ling Huang; Hsiang-Wei Hsing; Tzu-Chia Lai; Yi-Wen Chen; Tian-Ren Lee; Hsin-Tsu Chan; Ping-Chiang Lyu; Chieh-Lin Wu; Ying-Chieh Lu; Szu-Ting Lin; et al. Trypsin-induced proteome alteration during cell subculture in mammalian cells. Journal of Biomedical Science 2010, 17, 36-36, .