- Alias Symbols:
- Ig mu chain C region, IgM, IGHM
- Sample Type:
- Datasheets / Downloads:
- Additional Information:
- Intended Use: The KAPRRVM15 Rubella IgM u-capture ELISA test system, distributed by Aviva, is an Enzyme-Linked Immunosorbent Assay kit providing material for the detection of IgM-class antibodies to Rubella virus in human serum in order to confirm the primary Rubella infection.
- Reagents: The Rubella IgM ELISA kit, distributed by Aviva contains sufficient reagents for 96 wells.
As I understand it, the wells of the plate are coated with anti-hIgM mAb. Only a portion (if any) of the bound IgM in a given sample will be anti-Rubella IgM. The minimum amount of specific anti-Rubella IgM that can be detected with this kit is determined by this cut off control reagent. This anti-Rubella IgM fraction is detected directly via the Rubella antigen-HRP reagent.
The abundance of Rubella IgM is expressed as cut off index (COI) and is calculated as follows (do not use more than one decimal to express the abundance): Rubella IgM abundance = mean absorbance of control or patient specimen / mean absorbance of cut-off control = COI (Cut Off Index)
Samples are positive if the COI is > 1.1.
Samples are indeterminant if the COI is 0.9 – 1.1.
Samples are negative if the COI is < 0.9.
In order for the assay to be considered valid, your absorbance readings should follow this criteria:
Substrate Blank absorbance value: < 0.1
Negative Control absorbance value: < cut-off value
Cut-Off control absorbance value: 0.150 – 1.30
Positive control absorbance value: > cut-off value
Based on this criteria, the negative control is non-anti-Rubella hIgM, the positive control is anti-Rubella hIgM and the cut-off control is a mixture of the two calibrated to define the limit of detection of the assay.
The cut off control is based on very low positive titer (either at initial stages of primary infection, or very late stages). Alternatively, the positive control gives the indication of high titer, or peak immune response stages. If the OD of the positive control was used in order to find positive sample determination, it would risk missing the low positive cases. Therefore, the OD of the cut-off control is used in the ratio determination.
As far as published references, we have not yet published articles citing the use of this assay.