Prevalence and Isotypic Complexity of the Anti-Chinese Hamster Ovary Host Cell Protein Antibodies in Normal Human Serum

Chinese hamster ovary (CHO) cells are a mammalian cell line used in the production of therapeutic proteins. Host cell proteins (HCPs) are process-related impurities that are derived from the host cell expression system. During biopharmaceutical drug development, removal of HCPs is required. Enzyme-linked immunosorbent assay (ELISA) is a common technique to quantitate HCPs, but is a labor-intensive process that takes up to 7 h. Ella® is an automated instrument that utilizes microfluidics and glass nanoreactors to quantitate HCPs in 75 min using similar ELISA reagents. The antibodies and antigens are captured on three distinct glass nanoreactors, resulting in sensitive reproducible data. Our results indicate that Ella quantitates CHO HCPs with precision, accuracy, sensitivity and trends comparable with our traditional CHO HCP ELISA.

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Haemolysis and Reversible Agglutination of Trypsinized Normal Red Cells by a Normal Human Serum

Journal of Clinical Pathology ◽

10.1136/jcp.6.3.211 ◽

1953 ◽

Vol 6 (3) ◽

pp. 211-214 ◽

Cited By ~ 5

Author(s):

T. H. Hurley ◽

J. V. Dacie

Keyword(s):

Human Serum ◽

Red Cells ◽

Normal Human Serum ◽

Normal Human

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The Campylobacter jejuni CiaD effector co-opts the host cell protein IQGAP1 to promote cell entry

Nature Communications ◽

10.1038/s41467-021-21579-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Nicholas M. Negretti ◽

Christopher R. Gourley ◽

Prabhat K. Talukdar ◽

Geremy Clair ◽

Courtney M. Klappenbach ◽

...

Keyword(s):

Host Cell ◽

Campylobacter Jejuni ◽

Foodborne Pathogen ◽

Small Gtpase ◽

Host Cells ◽

Cell Protein ◽

Host Cell Protein ◽

Cell Binding ◽

Actin Reorganization ◽

Cell Cytosol

AbstractCampylobacter jejuni is a foodborne pathogen that binds to and invades the epithelial cells lining the human intestinal tract. Maximal invasion of host cells by C. jejuni requires cell binding as well as delivery of the Cia proteins (Campylobacter invasion antigens) to the host cell cytosol via the flagellum. Here, we show that CiaD binds to the host cell protein IQGAP1 (a Ras GTPase-activating-like protein), thus displacing RacGAP1 from the IQGAP1 complex. This, in turn, leads to the unconstrained activity of the small GTPase Rac1, which is known to have roles in actin reorganization and internalization of C. jejuni. Our results represent the identification of a host cell protein targeted by a flagellar secreted effector protein and demonstrate that C. jejuni-stimulated Rac signaling is dependent on IQGAP1.

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The isolation and identification of lysolecithin from lipid extracts of normal human serum

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)39094-5 ◽

1959 ◽

Vol 1 (1) ◽

pp. 66-71

Author(s):

Egil Gjone ◽

James F. Berry ◽

David A. Turner

Keyword(s):

Human Serum ◽

Normal Human Serum ◽

Isolation And Identification ◽

Normal Human

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Evaluation of a commercially available radioimmunoassay kit for measurement of doxorubicin in plasma.

Clinical Chemistry ◽

10.1093/clinchem/28.1.119 ◽

1982 ◽

Vol 28 (1) ◽

pp. 119-121 ◽

Cited By ~ 5

Author(s):

E Piall ◽

G W Aherne ◽

V Marks

Keyword(s):

Human Serum ◽

Normal Human Serum ◽

Nonspecific Effects ◽

Normal Human ◽

Doxorubicin Concentration

Abstract We evaluated a commercially available (Diagnostic Biochemistry Inc.) doxorubicin 125I radioimmunoassay kit. This kit gave a high apparent doxorubicin concentration (greater than 12 micrograms/L), which was not linearly related to dilution, for two pools of normal human serum and plasma and also for samples collected from patients before they received the drug. In contrast, a doxorubicin 3H radioimmunoassay developed by us gave a low blank (2 micrograms/L), which was linearly related to dilution, for the same pools and patients' samples. Doxorubicin concentrations in the plasma of patients receiving the drug were compared by the two methods; the kit gave results five- to 10-fold those obtained with our assay. High nonspecific interference by serum and plasma as measured by the 125I radioimmunoassay must therefore be borne in mind by users of the kit, and we suggest that results should be corrected for these nonspecific effects.

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