Related Experiment Video
Updated: Aug 3, 2026

Personalized Peptide Arrays for Detection of HLA Alloantibodies in Organ Transplantation
Published on: September 6, 2017
Association of HLA-DQ5 and HLA-DR1 with sensitization to organic acid anhydrides
Background:
Organic acid anhydrides are low molecular weight industrial chemicals, able to cause rhinoconjunctivitis and asthma associated with specific IgE against hapten-carrier protein conjugate. Only a proportion of exposed workers develop IgE-associated allergy to acid anhydrides.
Objective:
We determined whether genetic susceptibility, in particular, HLA Class II alleles may be a risk factor.
Methods:
We undertook HLA typing in 52 cases who had confirmed specific IgE and in 73 referents matched on site, age and duration of acid anhydride exposure identified in cross-sectional studies of workers exposed to hexahydrophthalic (HHPA), methylhexahydrophthalic (MHHPA) and methyltetrahydrophthalic (MTHPA) anhydrides.
Results:
The linked alleles DQ5 (odds ratio [OR]=4.3; 95% confidence interval [95% CI]=1.7, 11) and DR1 (OR 3.0; 95% CI 1.2, 11) were more prevalent in cases than in referents. Within DQ5, DQB1(*)0501 was particularly frequent (OR 3.0; 95% CI 1.2, 7.4).
Conclusion:
DQB1(*)05 gene confers susceptibility to develop specific IgE antibodies against HHPA, MHHPA and a non-significant trend with MTHPA. DQB1(*)0501 is protective for other low molecular chemical sensitizers (isocyanates and plicatic acid) which may indicate varying affinities for the corresponding specific class II molecules.
More Related Videos
Related Concept Videos
α-Halogenation of Carboxylic Acid Derivatives: Overview
Nomenclature of Carboxylic Acid Derivatives: Acid Halides, Esters, and Acid Anhydrides
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
Relative Reactivity of Carboxylic Acid Derivatives
A key factor in assessing the reactivity of the acid derivatives is the basicity of the substituent or the leaving group. The lower the basicity of the leaving group, the higher the reactivity of the derivative. The basicity of the leaving group follows this order:
Halide ions < Acyloxy ions < Alkoxy ions < Amine ions
Preparation of Acid Anhydrides
The carboxylate ion acts as a nucleophile that attacks the carbonyl carbon of the acid chloride to form a tetrahedral intermediate. Subsequently, the re-formation of the carbonyl group with the loss of the chloride ion as a leaving group leads to the formation of an acid...
Reactions of Acid Anhydrides
Substituent Effects on Acidity of Carboxylic Acids

