Antibody quality assessment

However, be aware that in spite of the usefulness of the MIB-1 antibody in assessing the rate of cell proliferation, the classification of cancers (e.g., breast cancer) by the size of the primary tumor and the presence and extent of lymph node metastases does not adequately explain differences in the clinical outcome of individual patients. Cell proliferation indices are commonly used, along with other diagnostic parameters, to estimate the risk of recurrence of a cancer for individual patients. Therefore, it is important to understand the relationship between various indices of proliferation such as MIB-1 labeling index and detection by either in situ hybridization or polymerase chain reaction. This approach will lead to quality assurance in diagnosis. 

ELISAs remain the mainstay of testing in which the specificity inherent in antibodies is exploited. The technique is still expanding in all fields of pure and applied biology, and in partieular, now constitutes a backbone diagnostic technique. Recent applications into quality assessment of foods for contaminants is testimony to the flexibility for these possible systems. There is an increasing use of automated systems in commercial applications of ELISA however, there is still a major use for more manual techniques in the development of assays, and for routine use in laboratories with lesser facilities. A thorough understand-... 

Aberer W, Woltsche M, Woltsche-Kahr I, Kranke B (2001) IgG antibodies typical for extrinsic allergic alveolitis - an interlaboratory quality assessment. Eur J Med Res 6 498-504... 

In order to assess the quality of the p53 protein microarrays printed on SAM2 membranes, two different assays are carried out on replica arrays. The antibodybinding assay comprises binding a Cy3-labeled anti-His antibody to the arrayed p53 proteins. This assay is independent of protein activity but provides a measurement of the relative amounts of protein immobilized in each spot. 

Reverse-phase protein arrays offer a robust new method of quantitatively assessing expression levels and the activation status of a panel of proteins. For this purpose, the lysate of protein(s) of interest is arrayed without selection via a capture molecule. This array can then be queried with an antibody or ligand probe, or an unknown biological component. Since an individual test sample is immobilized in each array spot, this array can be composed of a variety of different patient samples. Each array is incubated with one detection protein or antibody, and a single end point is measured across the arrayed cohort and can be directly compared across multiple samples. Replicates can be reproducibly printed at a given sitting, increasing quality control over a series of queried arrays (reviewed in [33]). 

Equilibrium is usually not reached during primary antibody incubations of less than 20 minutes. Consistent timing of this step is therefore important. Inconsistent incubation times can cause variations in overall stain quality and intensity, and may lead to incorrect interpretation of results. These criteria are particularly essential in efforts that attempt to assess the degree of tumor differentiation. 

Lubiniecld, A., VoUdn, D.B., Federici, M., et al. (2010) Comparability assessments of process and product changes made dining development of two different monoclonal antibodies. Biologicals, 39 (1), 9-22. Doblhoflf-Dier, O., BUem, R. (1999) Quality control and assurance from the development to the production of biopharmaceuticals. Trends Biotechnol, 17 (7), 266-270. 

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