Pires et al. (2002) [1103] reported a 16-month-old boy who developed urticaria on the face and neck immediately after local contact with raw garlic.

Perez-Pimiento et al. (1999) [1108] reported a patient who experienced three episodes of exercised induced anaphylaxis after eating when no specific food could be identified as allergenic. The individual subsequently presented generalized urticaria and facial angioedema, followed by a feeling of sickness, hypotension, and loss of consciousness, after eating young garlic with eggs and shrimp, but without exercise.

Asero et al. (1998) [1109] reported a patient who suffered systemic urticaria/angioedema after the ingestion of foods containing both raw or cooked garlic. Garlic also caused contact urticaria.

Pastorello et al. (1989) [1164] reported a single patient with rhinitis and diarrhoea on reintroduction of garlic after an elimination diet.

Kao et al. (2004) [1102] used two concentrations of purified garlic alliin lyase in phosphate buffered saline.

Pires et al. (2002) [1103] used commercial garlic extract (Stallergènes), fresh raw and fresh cooked garlic. Commercial onion extract (Stallergènes) and fresh raw and cooked onion were also used.

Perez-Pimiento et al. (1999) [1108] used commercial pollen extracts. Raw and cooked young garlic and garlic clove were used in prick-prick tests.

Asero et al. (1998) [1109] used commercial extracts of garlic (Dome-Hollister/Stier and Lofarma Allergeni, Milan) and other foods.

Kao et al. (2004) [1102] tested 12 patients.

Pires et al. (2002) [1103] tested 1 patient.

Perez-Pimiento et al. (1999) [1108] tested 1 patient.

Asero et al. (1998) [1109] tested 1 patient.

Kao et al. (2004) [1102] report that 12/12 patients (and 0 controls) gave positive SPT to 1 × 10^–8 mol/L of purified alliin lyase whereas 58% (7/12) also gave a positive response with the lower concentration of 2 × 10^–9 mol/L.

Pires et al. (2002) [1103] report that skin prick and prick-prick tests were positive with commercial garlic extract (Stallergènes) and fresh raw garlic with a wheal diameter of 15 X 9 mm and 17 X 8 mm, respectively. The prick-prick test was negative with fresh cooked garlic. Skin prick and prick-prick tests were negative with both commercial onion extract (Stallergènes) and fresh raw and cooked onion.

Perez-Pimiento et al. (1999) [1108] report positive SPTs with pollen of grass, trees (Platanus, Ulmus), and weeds (Artemisia, Taraxacum, Parietaria, and Chenopodium). SPTs were also positive to almond, hazelnut, peanut, walnut, sunflower seed, mustard, and Anisakis. In the prick-prick test, raw young garlic produced a wheal of 23 X 14 mm. Heated young garlic and garlic clove gave wheals of 8 X 4 and 10 X 6 mm, respectively.

Asero et al. (1998) [1109] report a strong skin reaction (wheal grade 4+ by comparison with 10 mg/ml histamine) was induced by two commercial garlic extract. No reaction was seen with onion or any other extract tested.

Commercial extracts were used with immunoCAP.

Kao et al. (2004) [1102] reported that 2/12 patients were class 1 and 10/12 patients class 2 for garlic specific IgE.

Pires et al. (2002) [1103] reported that specific IgE to garlic and onion (Pharmacia CAP System) were negative (< 0.35 kU/l).

Kao et al. (2004) [1102] made a crude garlic extract (also shallot, Allium ascalonicum, leek, Allium porrum, and onion, Allium cepa) by homogenizing for 6 × 30 seconds, with an interval of 30 seconds in ice-cold 50 mM phosphate buffer, pH 7.5, containing 1 mM PMSF, 1 mM calcium chloride, and 0.1 mM DTT (10 mL of buffer per gram of material). The homogenate was filtered through two layers of gauze and the filtrate centrifuged at 27,000 x g for 15 minutes at 4°C. Trichloroacetic acid was added to the supernatant solution (crude extract) to a final concentration of 20% and after standing for 15 minutes at 4°C, the sample was centrifugated at 12,000g for 15 minutes at 4°C and the pellet vacuum-dried on a SpeedVac (SC110, Savant, Farmingdale, NY). The pelleted material was analyzed by 2-dimensional (2-D) electrophoresis. An immobilized pH gradient of 3–10 on a horizontal electrophoresis system (Multiphor II, Pharmacia) was used for the first dimension. The second dimension used SDS PAGE with a separation gel of 12.5% polyacrylamide under reducing conditions (5% beta-mercaptoethanol).

Asero et al. (1998) [1109] extracted garlic proteins by stirring some cloves overnight at 4° C in 0.15M phosphate-buffered saline (pH 7.2) in the presence of 2% (w/v) polyvinylpolypyrrolidone, 10mM diethyldithiocarbamate, and 2mM ethylenediamine tetraacetic acid disodium salt. Particulate material was removed by centrifugation at 18,000xg for 30 minutes, and the supernatant was dialyzed against distilled water and lyophilized. Twenty micrograms of garlic extract was applied on a running gel (gradient 10% to 20%), and electrophoresis was carried out at 40 mA for 2 hours.

Kao et al. (2004) [1102] transferred proteins on to PVDF membranes (Millipore) by semi-dry blotting. The blotted membranes were then either stained directly with Coomassie Brilliant Blue R-250 or blocked with 1% skimmed milk in Tris-buffered saline, 20 mM Tris/HCl (pH 7.5) with 500 mM NaCl, at room temperature for 1h then incubated overnight at 4°C with patients' sera (pooled serum from patients 1 through 4) diluted 1:10 in Tris-buffered saline containing 1% v/v Tween-20 (TBST) and 1% w/v skimmed milk. After three washes with TBST, the blots were incubated with anti-human-IgE/alkaline phosphatase antibody (1:2000) for 1h at room temperature and development was carried out using a mixture of Nitro Blue Tetrazolium/5-bromo-4-chloroindol-3-yl phosphate toluidinium as substrate.

Asero et al. (1998) [1109] electrophoretically transferred proteins onto a nylon-cellulose membrane (Fluorotrans 0.45 µm; Pall, Milan, Italy). The membrane was saturated with 0.1 mol/L tris-buffered saline and 5% w/v fat-free milk powder and incubated with patient's serum after washings. Bound specific IgE (before and after adsorption on Protein A; see below) were detected by peroxidase-conjugated anti-human IgE antibodies from goat (1:1000 in saturation buffer) by using an ECL western blotting kit (Amersham, Milan, Italy). To verify if the presence in serum of anti-garlic extract IgG could interfere in the signal, the patient's serum was also adsorbed on Protein A-Sepharose CL-4B (Pharmacia, Milan, Italy). One milliliter of serum was added to 300 mg of not preswollen resin to avoid dilution of serum. After incubation for 3 hours at room temperature and centrifugation, serum was recovered and used in immunoblotting experiments.

Kao et al. (2004) [1102] report that 5 proteins bound IgE from the sera of 4 patients with similar masses of approximately 56 kDa. The spot at highest pI, 8.5, was excised and N-terminal amino acid sequencing gave the sequence KMTWTMKAAEEAEAVAN, which is identical to the N-terminal sequence of the mature form of garlic alliin lyase. The other spots with pI between 8.5 and 7 showed closely related sequences from MALDI mass spectroscopy.
The apparent molecular weights of the IgE-binding components identified by all 15 sera ranged from 31 to 60 kDa. The 56 kDa component was detected by all 15 sera. Other IgE-binding components of various molecular weights were detected at frequencies of less than 30%, for example, serum samples 3, 6, 10, and 13 gave a positive reactions to a 42-kDa component.

Pires et al. (2002) [1103] found two IgE binding bands with molecular masses of approximately 12 kDa and around 40-50 kDa, which they suggest probably correspond to the mannose-binding lectin and alliinase.

Perez-Pimiento et al. (1999) [1108] report that IgE from the patient's serum bound to a band at a molecular mass of approximately 12 kDa from raw young garlic (stem and bulb), garlic, onion, and leek. Other 12 kDa bands could also be observed with extracts of mugwort pollen and hazelnut. The serum also recognized an intense IgE binding band of about 22 kDa in mugwort pollen.

Asero et al. (1998) [1109] reported that there was weak binding of IgE to a garlic protein at 10 kDa. Adsorption of the patient's serum on protein A to remove IgG antibodies resulted in an intensification of the 10 kDa band and the appearance of further signals at about 20 and 40 kDa (and a possible band near 100 kDa).