The List Labs Citation Database is a robust tool for researchers. It offers thousands of papers showing how List Labs products are used experimentally. Researchers can search keywords specific to their fields of study and learn how others in that field have used our toxins and antigens.

In this article, we will explore experimental applications for two of our most popular products: Pertussis Toxin (Products #180, #181, and #184) and Cholera Toxin (Product #100B). This article is not exhaustive – we will focus on recent research – but it offers a survey of ways in which List Labs is helping to get science done.

Experimental autoimmune encephalomyelitis (EAE) is an induced autoinflammatory condition of the central nervous system. It is used in rodents as a model of demyelinating diseases such as multiple sclerosis and of T-cell-mediated autoimmune disease in general. Inducing EAE usually uses isolated myelin proteins or homogenate along with pertussis toxin to open the blood-brain barrier and allow T-cells access to the CNS. Many citations in the database note the use of those products.

But that’s far from the only way researchers have found to use List Labs’ pertussis toxin. An international team of researchers found that pertussis toxin reduces cellular damage following ischemic strokes. Another used it in their study of myocarditis. A Michigan team used pertussis toxin to develop an innovative high-molecular-weight mass spectrometry application. And of course, several research groups used it to develop assays and treatments for whooping cough.

The applications for cholera toxin are equally diverse. Besides treatments for cholera, researchers recently used the toxin to study the role of bone morphogenetic proteins and mesenchymal stem cells in breast cancer, as well as TRAIL therapy to treat such cancers. Other cancer researchers looked at hemocyanin as a treatment for bladder cancer, using List’s cholera toxin.

Investigators studied vaccines against Helicobacter pylori, which is known to cause peptic ulcers and is a risk factor for gastric cancer.

Food allergies are a serious and growing problem. Our citation database lists studies that used cholera toxin to aid in the study of allergies to several common foods (especially peanuts). Cholera toxin was also studied as an adjuvant for intranasal vaccines and used to investigate the role of immunoglobulin E (IgE) in anaphylactic shock—an extreme and potentially fatal allergic reaction.

Cholera toxin was even used to study the cellular mechanisms of Yersinia pestis, the pathogen that causes bubonic plague.

This is only a brief survey of recent research using two of List Labs’ more popular products. It illustrates both the wide range of applications for List’s bacterial toxins and the utility of the List citation database as a tool to facilitate your literature surveys.

Recent Research: Experimental Applications of Pertussis Toxin and Cholera Toxin

The List Labs Citation Database is a robust tool for researchers. It offers thousands of papers showing how List Labs products are used experimentally. Researchers can search for keywords specific to their fields of study and learn how others in that field have used our toxins and antigens.

In this article, we will explore experimental applications for two of our most popular products: Pertussis Toxin (Products #180, #181 and #184) and Cholera Toxin (Product #100B). This article is not exhaustive – we will focus on recent research – but it offers a survey of ways in which List Labs is helping to get science done.

Pertussis Toxin Applications

But that’s far from the only way researchers have found to use List Labs’ pertussis toxin. An international team of researchers found that pertussis toxin reduces cellular damage following ischemic strokes. Another used it in their study of myocarditis. A Michigan team used pertussis toxin to develop an innovative high-molecular-weight mass spectrometry application. And of course several research groups used it developing assays and treatments for whooping cough.

Cholera Toxin Applications

Investigators studied vaccines against Helicobacter pylori, which is known to cause peptic ulcers and is a risk factor for gastric cancer.

Cholera toxin was even used to study the cellular mechanisms of Yersinia pestis, the pathogen that causes bubonic plague.

By: M. Wessling

A recently published study by Wen et al [1] provides an encouraging look at a possible therapy for the chronic neuro-inflammatory disease multiple sclerosis (MS). What is even more interesting is that this experimental autoimmune encephalitis myelitis (EAE) study, which used the List Labs Product #180 Pertussis Toxin in mice to induce autoimmune symptoms, supports observations that MS patients and their physicians have accumulated for decades—the relationship between sunlight and MS progression. It also supported a 2015 study by Thouvenot et al [2] that showed a relationship between the degree of disability in fully ambulatory patients with the relapsing-remitting form of MS and Vitamin D deficiency, related in some cases to insufficient exposure to sunlight.

Challenges associated with MS treatments

Introducing and developing new effective treatments for MS is challenging because the disease has different levels and rates of progression in different patients. In fact, there is evidence that 25% to 50% of persons with MS choose not to take existing disease-modifying therapies, even though the risks and benefits are well known.[3] MS is also approximately 1.5 times more prevalent in women than men, and more frequent in more northerly regions, and MS is now being recognized more frequently in children than before.[4] Indeed, the prevalence of MS is prone to uncertainty; mostly since MRI, which is used to diagnose MS is not available in poorer regions. Another confounding factor is that in some traditions there may be a perceived cultural association between the symptoms at onset—fatigue, blurring of vision, motion impairments—and moral culpability.

Scientific research for MS treatments is progressing

However, recent years have brought much progress in the analytical scientific methods that show changes in cell structure in in vivo samples from patients with MS. Oxidative stress was identified as a major factor in the cell apoptosis that leads to neurodegenerative diseases, such as MS. The study by EM Kuklina [5] used blood samples from MS patients to conclude that melatonin plays a definitive role as an effective regulator of immune reactions that act through the subset of T lymphocytes producing IL-17 (Th17). As the Th17 subset plays a key role in MS pathogenesis, the results suggest that melatonin could nullify the immunomodulating hormone effects toward Th17.

The Wen EAE study bridges the gaps between scientific theory and human observation using genetically characterized mice under carefully controlled conditions. This study therefore could lead to new and effective therapies for MS. Going beyond previously published studies on the effects of melatonin, these authors examined the effects of treatment with melatonin and its precursor, N-Acetylserotonin (NAS), on neurodegenerative symptoms that parallel those in human MS. The EAE results showed clinical improvement that included reduced inflammatory markers and free radical generation, and sparing of axons, oligodendrocytes, and myelin. Further, the proposed mechanism would explain how the decline in motor symptoms in the NAS and melatonin-treated mice is linked to the role of Th1 cytokines in MS progression.

While it’s very different from our Pertussis Toxin, another List Labs product used in Multiple Sclerosis research is Epsilon Toxin (Product #126A). Read about it here: Epsilon Toxin: A Fascinating Pore Forming Toxin That Crosses The Blood Brain Barrier

See other uses of List Labs products in recent research on our Citations page, featuring thousands of articles with abstracts.

References

Wen J, Ariyannur PS, Ribeiro R, Tanaka M, Moffett JR, Kirmani BF, Namboodiri M, Zhang Y. Efficacy of N-Acetylserotonin and Melatonin in the EAE Model of Multiple Sclerosis. J Neuroimmune Pharmacol 2016 Aug. 25 [Epub ahead of print]. PMID: 27562847
Thouvenot E, Orsini M, Daures J-P, Camu W. Vitamin D Is Associated with Degree of Disability in Patients with Fully Ambulatory Relapsing-Remitting Multiple Sclerosis. Eur J Neurol 2015, 22: 564-569. PMID: 25530281
National Multiple Sclerosis Society. Multiple Sclerosis FAQ’s. New Research Fall 2015. Acquired 10/30/2016.
Alonso A, Hernán MA. Temporal Trends in the Incidence of Multiple Sclerosis: A Systematic Review. Neurology 2008; 71:129-135. 2008. PMID: 18606967
Kuklina EM. [Melatonin as an Inducing Factor for Multiple Sclerosis.] Zn Nevrol Psikhiatr Im S S Korsaakova. 116 (5):102-5. 2016. [Article in Russian]

By: Md. Elias, Ph.D, Senior Scientist

List Labs is one of the leading manufacturers of high quality adjuvants from bacterial sources. Our highly purified adjuvants for research and development are Tetanus Toxoid (Product #191), Cholera Toxin B Subunit (Product #104), Diphtheria Toxin CRM₁₉₇ Mutant (Product #149), Adenylate Cyclase Mutant, Cya-AC^– (Product #198L), Pertusis Toxin Mutant (Product #184), and LPS and its derivatives (Products #400, #401, #421, #423, #433, #434). GMP grade material is available by custom order.

In immunology, an adjuvant is a component that enhances and/or potentiates the immune responses (humoral and /or cell mediated) to an antigen and modulates it to achieve the desired immune responses. Adjuvants can be used for various reasons: (i) to enhance the immunogenicity of antigens; (ii) to reduce the amount of antigen or the number of immunizations needed for protective immunity; (iii) to improve the efficacy of vaccines in immune-compromised persons; (iv) to increase functional antibody titer; or (v) as antigen delivery systems for the uptake of antigens by the mucosa (1-3). Brief descriptions of List Labs products that have potential uses as vaccine adjuvants or immune modulators are provided below. For more details, please visit www.ListLabs.com.

Tetanus Toxoid (Product #191): Tetanus toxoid is prepared by formaldehyde inactivation of pure neurotoxin (Product #190). There are FDA approved vaccines that use a tetanus toxoid antigen to protect children and adult against tetanus such as DAPTACEL and Tripedia, and others that use it as a carrier in conjugate vaccines against various pathogens. For example, MenHibrix^® is an FDA approved vaccine where tetanus toxoid has been conjugated to Neisseria meningitidis serogroup C and Y capsular polysaccharides and Hib capsular polysaccharide. Several other tetanus toxoid conjugated vaccines are in research and investigation stages such as Type III group B streptococcal polysaccharide-tetanus toxoid conjugate vaccine (4). Information on our entire family of Tetanus products can be found at https://listlabs.com/products/tetanus-toxins-&-related-products/.

Cholera Toxin B subunit (Products #103B and #104): Cholera toxin B subunit (CTB) is the cell binding domain of cholera toxin protein complex. The holotoxin consists of a single A subunit bearing ADP-ribosyl-transferase activity surrounded by five B subunits that bind to GM1 ganglioside receptors on mammalian cell surfaces and facilitate entrance of the A subunit into cells. The non-toxic CTB has been shown to be an efficient mucosal adjuvant and carrier molecule for the generation of mucosal antibody responses and/or induction of systemic T-cell tolerance to linked antigens. Due to the ubiquitous presence of the GM1 ganglioside receptor on eukaryotic cell membranes, CTB has been extensively used as a conjugate and non-conjugate vaccine adjuvant in a wide variety of model systems.

A CTB-urease conjugated vaccine has been shown to prevent infection by Helicobacter pylori, a bacterium that infects greater than 50% of world population and can cause a variety of gastrointestinal diseases (5). A series of studies have been carried out to develop CTB carrier based vaccines to prevent HIV-1 (6) and West Nile Virus infections (7). CTB has been used as a component of a skin patch for transcutaneous immunization against hepatitis B virus in a mouse model (8). Besides the adjuvant activity, recent studies show that CTB can suppress immunopathological reactions in allergy and autoimmune diseases such as Crohn’s disease (9). Information on our entire family of Cholera products can be found at https://listlabs.com/products/cholera-toxins/.

Diphtheria Toxin CRM₁₉₇ Mutant (Product #149): CRM₁₉₇ is a non-toxic mutant of diphtheria toxin lacking the ADP-ribosylation activity (10). CRM₁₉₇ results from a naturally occuringsingle base change (glutamic acid to glycine) in the toxin gene which is immunologically indistinguishable from the native diphtheria toxin. CRM₁₉₇ functions as a carrier for polysaccharides and haptens making them immunogenic (11, 12). It is utilized as a carrier to develop conjugate vaccines for diseases such as pneumococcal and meningococcal infections. MenACWY-CRM is an approved vaccine to protect adults and adolescents against disease caused by meningococcal serogroups A, C, W-135 and Y. Information on our entire family of Diphtheria products can be found at https://listlabs.com/products/diphtheria-toxins/.

Adenylate Cyclase Toxoid, Cya-AC^– (Product #198L): A genetically modified adenylate cyclase toxin (ACT) lacking adenylate cyclase activity (CyaA-AC^–) has been produced (13). Although the catalytic activity is destroyed, CyaA-AC^– is still cell invasive and able to induce an immune response to co-administered pertussis antigens (14, 15). CyaA-AC^– has been shown to promote delivering of vaccine antigens into the cytosol of major histocompatibility complex (MHC) class I antigen-presenting cells (16). CyaA-AC^– has been used as a tool to deliver antigens to T-cells in anti-cancer immunotherapeutic vaccines (17, 18).

Pertussis Toxin Mutant (Product #184): List Labs produces Pertussis Toxin Mutant, a genetically inactivated form of pertussis toxin where mutations were introduced to abolish the catalytic activity of the S1 subunit while the toxin complex still retains the cell binding ability (19). A pertusis toxin mutant has been used as an adjuvant or as a carrier to promote an immune response. These studies indicated that pertussis toxin mutant possesses adjuvant properties with the ability to encourage both local and systemic responses, to promote T helper cell responses to co-administered antigens and to favor the production of Th1/Th17 cells, important in mediating host immunity to infectious pathogens (20). Pertusis toxin binds to the cell receptor, TLR4 which activates Rac and subsequently causes various effects depending on the type of cell treated (21). The toxin or binding oligomer induces dendritic cell maturation in a TLR4-dependent manner (22). Information on our entire family of Pertussis products can be found at https://listlabs.com/products/pertussis-toxins-&-virulence-factors/.

LPS and its derivatives: List Labs provides LPS and various derivatives: highly purified HPT^TM LPS from Escherichia coli O113 (Product #433); Ultar Pure Escherichia coli O111:B4 LPS (Product #421); Escherichia coli O55:B5 LPS (Product #423); Ultra pure LPS from Salmonella Minnesota R595 (Product #434); Lipid A Monophosphoryl from Salmonella Minnesota R595 (Product #401) and highly purified HPT^TM LPS from Bordetella pertusis strain 165 (Product #400). For other LPS products please go to our product website. These LPS products are widely used as vaccine adjuvants and immune stimulators.

LPS is a potent stimulator of the vertebrate innate immune system mediated by macrophages and dendritic cells and generates a rapid response to infectious agents. Structural patterns common to diverse LPS molecules are recognized by Toll-like receptors (TLR) and accessory proteins in serum. LPS released from bacterial membranes is bound to LPS binding protein (LBP) in serum, transferred to CD-14, an LPS receptor glycoprotein, and presented to the TLR-4-MD-2 complex, stimulating production of cytokines. LPS has a wide range of uses in research and drug development. It may be used to stimulate immune cells and investigate the innate immune responses. In drug development, structurally modified LPS forms, such as monophophoryl lipid A (MPLA) have been used as adjuvants in a wide range of vaccine formulations. MPLA, a TLR4 agonist has been formulated with liposomes, oil emulsions, or aluminium salts for several vaccines such as malaria vaccine (known as RTS,S) that is comprised of MPLA and a detoxified saponin derivative, QS-21 (3). Information on our entire family of Lipopolysaccharides can be found at https://listlabs.com/products/lipopolysaccharides/.

List Labs specializes in producing high quality adjuvants for vaccine development and is interested in partnering with others on new projects. See some of our special projects or contact us for more information.

Lee S.,Nguyen M.T. Recent advances of vaccine adjuvants for infectious diseases. Immune Netw. 2015, 15(2): 51-7. PMID: 25922593
Petrovsky N., Aguilar J.C. Vaccine adjuvants: current state and future trends. Immunol Cell Biol.2004, 82(5): 488-96. PMID: 15479434
Alving C.R., Peachman K.K.,Rao M., Reed S.G. Adjuvants for human vaccines. Curr Opin Immunol. 2012, 24 (3):310-5. PMID: 22521140
Baker C.J., Rench M.A., McInnes P. Immunization of pregnant women with group B streptococcal type III capsular polysaccharide-tetanus toxoid conjugate vaccine. 2003. 21(24)3468-72. PMID: 12850362
Guo L., Li X., Tang F., He Y., Xing Y., Deng X., Xi T. Immunological features and the ability of inhibitory effects on enzymatic activity of an epitope vaccine composed of cholera toxin B subunit and B cell epitope from Helicobacter pylori urease A subunit. Appl Microbiol Biotechnol. 2012, 93(5):1937-45. PMID: 22134639
Matoba N., Kajiura H., Cherni I., Doran J.D., Bomsel M., Fujiyama K., Mor T.S. Biochemical and immunological characterization of the plant-derived candidate human immunodeficiency virus type 1 mucosal vaccine CTB-MPR. Plant Biotechnol J.2009, 7(2):129-45. PMID: 19037902
Tinker J.K., Yan J., Knippel R.J., Anayiotou P., Ornell K.A. Immunogenicity of a West Nile virus DIII-cholera toxin A2/B chimera after intranasal delivery. Toxins (Basel).2014, 6(4):1397-418. PMID: 24759174
Anjuere F., George-Chandy A., Audant F., Rousseau D., Holmgren J., Czerkinsky C. Transcutaneous immunization with cholera toxin B subunit adjuvant suppresses IgE antibody responses via selective induction of Th1 immune responses. J Immunol.2003, 170(3):1586-92. PMID: 12538724
Sun J.B., Czerkinsky C.,Holmgren J. Mucosally induced immunological tolerance, regulatory T cells and the adjuvant effect by cholera toxin B subunit. Scand J Immunol. 2010, 71(1):1-11. PMID: 20017804
Pappenheimer Jr. A.M., Uchida T., Harper A.A. An immunological study of the diphtheria toxin molecule. 1972, 9(9):891-906. PMID: 4116339
Gupta R.K., Siber G.R. Reappraisal of existing methods for potency testing of vaccines against tetanus and diphtheria. 1995, 13(11): 965-6. PMID: 8525688
Benaissa-Trouw B., Lefeber D.J, Kamerling J.P., Vliegenthart J.F., Kraaijeveld K., Snippe H. Synthetic polysaccharide type 3-related di-, tri-, and tetrasaccharide-CRM (197) conjugates induce protection against Streptococcus pneumoniae type 3 in mice. Infect Immun.2001, 69(7):4698-701. PMID: 11402020
Simsova M., Sebo P., Leclerc C. The adenylate cyclase toxin from Bordetella pertussis–a novel promising vehicle for antigen delivery to dendritic cells. Int J Med Microbiol. 2004, 293(7-8):571-6. PMID: 15149033
Macdonald-Fyall J., Xing D., Corbel M., Baillie S., Parton R., Coote J. Adjuvanticity of native and detoxified adenylate cyclase toxin of Bordetella pertussistowards co-administered antigens. 2004, 22(31-32):4270-81. PMID: 15474718
Cheung G.Y., Xing D., Prior S., Corbel M.J., Parton R., Coote J.G. Effect of different forms of adenylate cyclase toxin of Bordetella pertussis on protection afforded by an acellular pertussis vaccine in a murine model. Infect Immun.2006, 74(12):6797-805. PMID: 16982827
Osicka R., Osicková A., Basar T., Guermonprez P., Rojas M., Leclerc C., Sebo P. Delivery of CD8(+) T-cell epitopes into major histocompatibility complex class I antigen presentation pathway by Bordetella pertussis adenylate cyclase: delineation of cell invasive structures and permissive insertion sites. Infection Immunity, 2000, 68(1): 247-256. PMID: 10603395
Dadaglio G., Morel S., Bauche C., Moukrim Z., Lemonnier F.A., Van Den Eynde B.J., Ladant D., Leclerc C. Recombinant adenylate cyclase toxin of Bordetella pertussisinduces cytotoxic T lymphocyte responses against HLA*0201-restricted melanoma epitopes. Int Immunol. 2003 15(12):1423-30. PMID: 14645151
Fayolle C., Ladant D., Karimova G., Ullmann A., Leclerc C. Therapy of murine tumors with recombinant Bordetella pertussisadenylate cyclase carrying a cytotoxic T cell epitope. J Immunol. 1999, 162(7):4157-62. PMID: 10201941
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Nasso M., Fedele G., Spensieri F., Palazzo R., Costantino P., Rappuoli R., Ausiello C.M. Genetically detoxified pertussis toxin induces Th1/Th17 immune response through MAPKs and IL-10-dependent mechanisms. J Immunol. 2009, 183(3):1892-9. PMID: 19596995
Nishida M.,Suda R., Nagamatsu Y., Tanabe S., Onohara N., Nakaya M., Kanaho Y., Shibata T., Uchida K., Sumimoto H., Sato Y., Kurose H. Pertussis toxin up-regulates angiotensin type 1 receptors through Toll-like receptor 4-mediated Rac activation. J Biol Chem. 2010, 285(20):15268-77. PMID: 20231290
Wang ZY., Yang D., Chen Q., Leifer C.A., Segal D.M., Su S.B., Caspi R.R., Howard Z.O., Oppenheim J.J. Induction of dendritic cell maturation by pertussis toxin and its B subunit differentially initiate Toll-like receptor 4-dependent signal transduction pathways. Exp Hematol. 2006, 34(8):1115-24. PMID: 16863919