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For Research Use Only in the United States. Not for use in diagnostic procedures.

The MicroVue Ba EIA measures the amount of Ba present in human urine, serum, plasma and other biological or experimental samples.

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 substances including microbial polysaccharides or lipids, gram-negative bacterial lipopolysaccharides, and surface determinants present on some viruses, parasites, virally infected mammalian cells, and cancer cells. In autoimmune diseases, the alternative complement pathway may contribute directly to tissue damage.

A centrally important reaction that occurs during alternative pathway activation is the conversion of the 93 Kd molecular weight Factor B zymogen to an active proteolytic enzyme. This is accomplished in a two-step reaction. During the first reaction step the Factor B forms a magnesium-dependent complex with C3(H20) or C3b. The C3(H20),B complex is formed only in fluid-phase while the C3b,B complex can be formed either in fluid-phase or on a target surface.  Factor B, which is present in the C3(H20),B or the C3b,B complex, is cleaved into the Ba (33 Kd) and Bb (60 Kd) fragments in the second reaction step by the alternative pathway enzyme, Factor D.

The MicroVue Ba Enzyme Immunoassay measures the concentration of Ba in human urine, plasma, serum and other experimental samples. It uses a proprietary monoclonal antibody that binds specifically to Ba to capture Ba in solid phase. The trapped Ba is then detected by HRP-labeled antibodies to Ba antigens. This test provides a quantitative measurement of Ba levels and is designed for investigations into the role and status of alternative complement pathway activation in numerous clinical and research settings.


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Features & Benefits


Product Specifications

Product Spec NameProduct Spec Data


Assay time

135 minutes


96 wells/plate

Sample type


Ordering Information

Catalog NumberDescription

ELISA Kit, control included

A034 XUS

ELISA Kit, control included

Complement Activation and
Biological Functions Video