Our group carries out control testing to ensure the quality and safety of diphtheria vaccines and antitoxins, and develops biological standards. This work is underpinned by research that focuses on:
Diphtheria is an acute, potentially fatal, infectious disease caused by toxigenic strains of Corynebacteria, primarily Corynebacterium diphtheriae. Diphtheria toxin – the most important virulence factor for disease-causing strains – is an exotoxin that inhibits cellular protein synthesis, resulting in cell death.
Vaccination and treatment
Diphtheria is well controlled by immunisation – although there can still be significant outbreaks where there is insufficient vaccination coverage. Diphtheria vaccine, produced by chemical inactivation of the purified diphtheria toxin (to produce toxoid), is a key component of combined vaccines used in routine immunisation programmes worldwide.
Diphtheria toxoid is adsorbed onto an adjuvant such as aluminium hydroxide or aluminium phosphate to increase antigenicity, and is used alone – or more commonly with other antigens – in combined vaccines. These combined vaccines may contain antigens against tetanus, pertussis, polio, Haemophilus influenzae type b and Hepatitis B virus. Regular booster vaccination with diphtheria toxoid is recommended to maintain protective levels of circulating diphtheria antitoxin. Diphtheria antitoxin – produced by hyperimmunising horses with diphtheria toxoid/toxin – is given to patients with suspected cases of diphtheria.
NIBSC is responsible for developing, producing and characterising biological reference materials used for standardising diphtheria vaccines, antitoxins and related products or intermediates. We maintain a portfolio of diphtheria standards, including toxoids, toxins and antitoxins that are used to standardise:
We design and coordinate international collaborative studies to characterise and calibrate new and replacement International Standards. Recently established International Standards include the 1st WHO International Standard for Diphtheria Antitoxin Human and the 4th WHO International Standard for Diphtheria Toxoid Adsorbed. We also work closely with formulation scientists at NIBSC to optimise formulations to successfully freeze-dry diphtheria standards.
NIBSC carries out control testing as part of the Official Control Authority Batch Release (OCABR) process for products licensed in the EU. We also do testing for the World Health Organisation (WHO) prequalification process for vaccines. We have wide experience in testing diphtheria vaccines, antitoxins and related intermediates and can perform assays for:
We have wide experience in developing and validating methods used in controlling and standardising diphtheria vaccines, antitoxins and related intermediates. We focus on methods that can be used to refine, reduce or replace animal testing – known as the 3Rs – and have developed an in vitro assay to monitor consistent production of diphtheria vaccines.
Contact us by emailing firstname.lastname@example.org for information about control testing, standardisation or potential research collaboration.
13/212: 3rd International Standard for Diphtheria Toxoid for use in Flocculation Test07/216: Diphtheria Toxoid (Adsorbed) (4th International Standard)10/128: Diphtheria Polyclonal Antibody10/130: Diphtheria Monoclonal Antibody10/262: 1st International Standard for Diphtheria Antitoxin Human12/282: Diphtheria Toxin Liquid63/007: Diphtheria Antitoxin, Equine, for Flocculation Test66/153: Diphtheria Antitoxin, Equine69/017: Diphtheria Toxoid, Plain98/572: Diphtheria and Tetanus Antitoxin, Guinea Pig Serum98/686: Control Guinea Pig SerumSTT: 1st International Standard for Diphtheria (Schick) Test Toxin17/230: Diphtheria Antitoxin Equine (DI) 1st International Standard