Rapid method of determining clearance of prion protein
OwnerKang Cai, Christopher Stenlandinventors
Life of this patent
Estimating the term…
Abstract
The invention provides a rapid, sensitive immunoassay capable of detecting and quantitating pathogenic protein to a level of 3 to 5 logs. The preferred immunoassay utilized is a chemiluminescent endpoint for a Western blot immunoassay. The invention has been successfully applied to track the clearance of pathogenic protein during production of proteins derived from plasma. It is particularly applicable and has been confirmed by bioassay to relate TSE infectivity to quantitative results on prion protein.
Claims22
An immunoassay method useful for determining the presence of TSE protein in a biological sample, comprising the steps of:
- a) preparing a relevant biological sample for a Western blot immunoassay;
- b) performing the Western blot immunoassay on such sample for TSE protein;
- and
- c) quantitating the TSE protein present wherein the immunoassay is carried out using a labeled TSE-specific antibody or antibody fragment.
An immunoassay method useful for determining the presence of TSE protein in a biological sample, comprising the steps of:
- a) diluting the biological sample with a physiologically compatible buffer to form a buffered dilution;
- b) treating the buffered dilution with proteinase-K to form a buffered proteinase-K dilution;
- c) performing a Western blot immunoassay for TSE protein on the biological sample;
- and
- d) quantitating the TSE protein present, wherein the immunoassay is carried out using a labeled TSE-specific antibody or antibody fragment.
A quantitative Western blot immunoassay method useful for the determination of TSE protein clearance during the processing of plasma products, comprising the steps of:
- a) preparing an aliquot of a relevant first sample chosen from plasma or a processed plasma sample for a Western blot immunoassay;
- b) performing the Western blot assay for TSE protein on such first sample;
- c) quantitating TSE protein in the first sample aliquot;
- d) subjecting the first plasma sample or first processed plasma sample to a processing treatment producing a second sample;
- e) performing a Western blot assay for TSE protein on an aliquot of the second sample;
- f) quantitating TSE protein results in the second sample;
- and
- g) comparing the quantitative TSE protein in the first sample to the quantitative TSE protein in the second sample to determine if the processing step provides detectable TSE protein clearance,
- wherein the Western blot assays are carried out using a labeled TSE-specific antibody or antibody fragment.
A method of determining TSE protein clearance by a particular plasma processing step:
- a) taking a sample of plasma paste prior to the processing step of interest;
- performing a Western blot analysis on the plasma paste sample to quantitate TSE protein content;
- b) spiking the plasma paste with known amount of scrapie brain homogenate;
- resuspending the spiked paste;
- c) taking an aliquot of the resuspended spiked paste;
- and performing a Western blot analysis on the resuspended spiked paste to quantitate TSE protein content;
- d) performing the processing step of interest on the plasma paste thereby obtaining a processed paste and an effluent;
- e) taking a sample of the processed paste and performing a Western blot analysis to quantitate TSE protein content in the processed paste;
- and
- f) comparing TSE protein content of the samples tested to determine if satisfactory TSE protein clearance has been obtained,
- wherein the Western blot assays are carried out using a labeled TSE-specific antibody or antibody fragment.
An immunoassay method useful for determining the presence of TSE protein in a biological sample, comprising the steps of:
- a) preparing a relevant biological sample for a Western blot immunoassay;
- b) performing the Western blot immunoassay on such sample for TSE protein;
- and
- c) quantitating the TSE protein present
- wherein the immunoassay is carried out using a labeled TSE-specific antibody fragment lacking the Fc portion of the antibody.
Dependencies are inferred from the claim text.