STUDENT: Cassandrea TG02
LABORATORY: Immunochemistry

The ARCHITECT

o Uses chemiluminescent microparticle immunoassay for the qualitative detection of the antigen or antibody in the serum and plasma of the paitent.

o Two-step immunoassay:
 Sample and antibody/antigen coated with paramagnetic microparticles are combined
 After washing, acridinium-labeled antibody/antigen is added.
 After another round of washing, solutions are added to the reaction mixture, resulting in the chemiluminescent reaction measured by relative light units (RLUs)
 The RLUs is compared to the cutoff signal determined by calibration which will determine if the results are reactive or non-reactive

o Two versions of ARCHITECT in the immunochemistry
ARCHITECT 2000 and ARCHITECT I 2000 SR (newer version)

o Types of test run in ARCHITEST 2000 tests involving hormones like beta-hCG, FSH, LH, Estradiol , prolactin and GH

o Types of test run in ARCHITECT I 2000 SR tests involving viruses like HIV, Syphilis, Hepatitis B and Rubella and thyroid tests which consist of free T4, TSH and calcitonin.

Clinical significance of measuring:

 HBeAg
o First detectable in the early phase of hepatitis B after appearance of hepatitis B surface antigen (HBsAg) early detection of disease
o Both antigen rise rapidly during viral replication in acute infection
o However, patients may not have HBeAg during infection but are still positive for hepatitis B if the antibodies (anti-HBe) to HBeAg are present

 Anti-Hbe
o Used to monitor the convalescence and recovery from hepatitis B infected individuals
o Presence of anti-Hbe and loss of HbeAg after acute infection is a good indication of recovery
o Samples with less than 10.0mIU/mL considered non-reactive
o Samples with greater than or equal to 10.0mIU/mL are considered reactive.

 HbsAg
o Aid in the diagnosis of suspected HBV infection and monitor the status of infected individuals
o Diagnosis of acute or chronic hepatitis HbsAg reactivity should be correlated with patient history and other hepatitis B serological markers
o Negative results need not be tested further but reactive results are retested

 -hCG
o hCG is a sialoglycoprotein initially secreted by the trophoblastic cells of placenta shortly after implantation of fertilized ovum into uterine wall
o Rapid rise in hCG levels after conception makes it an excellent marker for conformation and monitoring of pregnancy
o The hCG increases to peak concentration then decrease an plateau
o HCG levels can be useful in the prediction of spontaneous abortions, aiding in the detection of ectopic pregnancy and multiple gestation

 Ferritin
 High molecular weight iron–containing protein that functions as iron storage compound
 25% of iron in the body is present in various storage forms; 2/3 of the iron stores exist in the form of Ferritin
 Ferritin provides a more sensitive, specific and reliable measurement for determining iron deficiency at an early stage