MicroVue Bb Plus EIA | A027

MICROVUE™ Bb Plus Enzyme Immunoassay (EIA)

The MicroVue Bb Plus EIA measures the amount of Bb present in human plasma and serum. Because Factor B is unique to the alternative complement pathway, Bb is an excellent marker for alternative pathway activation.

The alternative complement pathway provides innate protection against microbial agents in the absence of specific antibody. The activation of this complement pathway can be triggered by a variety of different chemical moieties and substances including LPS, bacterial lipids and polysaccharides, virally infected mammalian cells as well as transformed cancer cells.

Centrally important to the alternative pathway is the zymogen Factor B. Factor B is a 93 kD protein which is converted to an active proteolytic enzyme via a two step reaction involving C3b and Factor D. Factor B binds to C3b (or hydrolyzed C3) either in fluid phase or on a membrane or other surface. In the second step, Factor D cleaves the bound Factor B to yield Ba (33 kD) and Bb (60KD) The resulting bimolecular complex is the alternative pathway convertase and is capable of cleaving additional C3 or, together with a second C3b molecule, C5.

The Bb fragment may become dissociated from the C3 or C5 convertases either through spontaneous decay or via the action of Factor H or CR

Since the Bb molecule is unique to the alternative pathway of complement, levels of Bb provide an excellent marker for complement activation via this pathway.

Product Specifications

Scientific Validation

• Citations: 47 peer-reviewed publications

Kit Format

• Size: 96 wells / test
• Form: 96-well microplate with 12 removable 8-well strips, supplied in a resealable foil pouch

Sample Requirements

• Specimen: Serum or EDTA plasma
• Sample Volume:

                - Serum : 25 µL

                - EDTA Plasma : 50 µL

Analytical Performance

• Limit of Detection (LOD): 0.018 µg/mL
• Lower Limit of Quantification (LLOQ): 0.033 µg/mL
• Upper Limit of Quantification (ULOQ): 0.836 µg/mL

Precision

• Intra-Assay CV: 2.4–4.0%
• Inter-Assay CV: 6.2–9.1%

Calibration & Controls

• Standards: 5
• Controls: 2

Expected Sample Values

• Serum: 0.0–7.6 µg/mL
• EDTA Plasma: 0.3–1.7 µg/mL

Assay Conditions

• Total Assay Time: Approximately 1.5 hours

Cross-Reactivity

• Cynomolgus Monkey
• Pig
• Rhesus Monkey

Storage

• Store unopened kits at 2°C to 8°C
• Refer to the Product Insert for additional storage and stability information