Giardia Iamblia Antigen ELISA Assay Kit

$500.00

This Eagle Biosciences Giardia Iamblia Antigen ELISA (enzyme linked immunosorbent assay) kit is intended for the qualitative detection of Giardia lamblia antigen in feces. The assay is a useful tool in the diagnosis of active Giardia lamblia infection in acute or chronic gastroenteritis.  The Eagle Biosciences Giardia Iamblia ELISA Assay kit is intended for research use only and not intended for diagnostic procedures.

SKU: GIA35-K01 Categories: , ,

Giardia Iamblia Antigen ELISA Assay Kit

For Research Use Only

Size: 1×96 wells
Sensitivity: Cut-off
Incubation Time: 2 hours
Sample Type: Stool
Sample Size: 50 mg

Controls Included

Product Developed and Manufactured in the USA


Additional Information

Assay Background

Giardia lamblia (also known as Giardia intestinalis) has a characteristic tear-drop shape and measures 10-15 µm in length. It has twin nuclei and an adhesive disk which is a rigid structure reinforced by supelicular microtubules. There are two median bodies of unknown function, but their shape is important for differentiating between species. There are 4 pairs of flagella, one anterior pair, two posterior pairs and a caudal pair. These organisms have no mitochondria, endoplasmic reticulum, golgi, or lysosomes. Giardia has a two-stage life cycle consisting of trophozoite and cyst. The life cycle begins with ingested cysts, which release trophozoites (10-20 µm x 5-15 µm) in the duodenum. These trophozoites attach to the surface of the intestinal epithelium using a ventral sucking disk and then reproduce by binary fission. The trigger for encystment is unclear, but the process results in the inactive, environmentally resistant form of Giardia — a cyst (11-14 µm x 7-10 µm) that is excreted in feces.

Giardiasis is a diarrheal illness caused by Giardia lamblia, after ingestion of Giardia cysts. Once a person has been infected with Giardia, the parasite lives in the intestine and is passed in the stool. Millions of germs can be released in a bowel movement from an infected human or animal. Giardia is found in soil, food, water, or surfaces that have been contaminated with the feces from infected humans or animals. Because the parasite is protected by an outer shell, it can survive outside the body and in the environment for long periods of time.

Because it is spread world-wide, Giardia lamblia has become one of the most important causes of chronic diarrhea. About 15-20% of children under age ten years and 19% of male homosexuals have been infected. Giardia infection can cause a variety of intestinal symptoms either acute or chronic, which include diarrhea, gas or flatulence, greasy stools that tend to float, stomach cramps, upset stomach or nausea. These symptoms may lead to weight loss and dehydration. Some people with giardiasis have no symptoms at all. Those asymptomatic cases still shed Giardia cysts. Generally, symptoms of giardiasis begin 1 to 2 weeks after becoming infected and they may last 2 to 6 weeks.

The method used for the diagnosis of giardiasis in the past has been the detection of Giardia cysts in stool by microscopy. Recently, specific Giardia antigen ELISA greatly simplified the diagnostic procedure and is as sensitive as the microscopic method. Another advantage of using Giardia antigen ELISA is that it does not require the intact organisms in the test specimen.

Assay Principle

This Eagle Biosciences  “sandwich” Fecal Giardia Iamblia Antigen ELISA is designed, developed and produced for the qualitative measurement of Giardia lamblia antigen in stool specimen. The assay utilizes the microplate-based enzyme immunoassay technique by coating highly purified antibody onto the wall of microtiter well.  Assay controls and fecal specimen are added to microtiter wells of microplate that was coated with a highly purified polyclonal anti-Giardia lamblia antibody on its wall. The Giardia lamblia antigen will be bound to the antibody coated plate after an incubation period. The unbound matrices are washed away and a HRP-conjugated monoclonal antibody which specifically recognizes the protein of Giardia lamblia is added for further immunoreactions.  After an incubation period, an immunocomplex of “Anti-Giardia Antibody – Giardia lamblia Antigen – HRP-conjugated Anti-Giardia Tracer Antibody” is formed if Giardia lamblia antigen is present in the test sample. The unbound tracer antibody and other protein or buffer matrix are removed in the subsequent washing step. HRP-conjugated tracer antibody bound to the well is then incubated with a substrate solution in a timed reaction and then measured in a spectrophotometric microplate reader. The enzymatic activity of the tracer antibody bound to giardia proteins captured on the wall of each microtiter well is directly proportional to the amount of Giardia lamblia antigen level in each test specimen

  1. Place a sufficient number of anti-Giardia antibody-coated microwell strips in a frame to run giardia controls and unknown samples in duplicate.
  2. Add 100 µL of controls and diluted patient stool samples into each designated microwell.
  3. Cover the plate with a plate sealer and also with aluminum foil to avoid exposure to light.
  4. Incubate plate at room temperature for 1 hour.
  5. Prepare working anti-Giardia tracer antibody working solution by 1:21 fold dilution of the Anti-Giardia Tracer Antibody with the Tracer Antibody Diluent. For each strip, it is required to mix 1 mL of Tracer Antibody Diluent with 50 µL of Tracer Antibody in a clean test tube.
  6. Remove the plate sealer. Decant the contents of each well. Wash each well 5 times by dispensing 350 µL to 400 µL of deionized or distilled water into each well and then completely aspirating the contents. Alternatively, an automated microplate washer can be used. (Note: The plate must not be washed with any ELISA wash buffer!)
  7. Add 100 µL of above diluted tracer antibody working solution to each of the wells.
  8. Cover the plate with one plate sealer and also with aluminum foil to avoid exposure to light.
  9. Incubate plate at room temperature for 45 minutes.
  10. Remove the plate sealer. Decant the contents of each well. Wash each well 5 times by dispensing 350 µL to 400 µL of deionized or distilled water into each well and then completely aspirating the contents. Alternatively, an automated microplate washer can be used. (Note: The plate must not be washed with any ELISA wash buffer!)
  11. Add 100 µL of ELISA HRP Substrate into each of the wells.
  12. Cover the plate with aluminum foil to avoid exposure to light.
  13. Incubate plate at room temperature for 20 minutes.
  14. Remove the aluminum foil.  Add 100 µL of ELISA Stop Solution into each of the wells. Mix gently.
  15. Read the absorbance at 450 nm within 10 minutes in a microplate reader. As an alternative, one can interpret the test results visually by using the color code card included in the kit.

Manual

Product Manual