Gala Araujo | ALES Graduate Seminar

Event details: A graduate exam seminar is a presentation of the student’s final research project for their degree.
This is an ALES MSc Final Exam Seminar by Gala Araujo. This seminar is open to the general public to attend.

Zoom Link: https://us02web.zoom.us/j/86508177408?pwd=SjAxOUhPeHNyazNuNlRDRm9vdmp6Zz09

MSc with Dr. Spencer Proctor.

Thesis Topic: Immunogenicity of Novel CHO- and HEK293- Produced Variants of the Atheroprotective chP3R99 mAb in Distinct Animal Models

Abstract:

Cardiovascular diseases remain a leading cause of death worldwide, with many cases linked to vascular occlusion; a process known as atherosclerotic vascular disease (ASVD). ASVD is characterized by the accumulation of cholesterol-rich lipoproteins within the arterial wall and is attributed to an ionic interaction with proteoglycans (PGs) in the extracellular matrix. A novel monoclonal antibody (mAb) known as chP3R99, has been demonstrated to directly interfere with lipoprotein retention by binding to PG-associated chondroitin sulfate (CS) groups. In addition, studies have accredited prolonged athero-protective features of chP3R99 mAb in-vivo with the induction of secondary (Ab2; anti-chP3R99) and tertiary (Ab3; anti-CS) antibodies in the host. However, production inefficiencies of the original (NS0) cell line have led to the development of more efficient chP3R99 variants; Chinese Hamster Ovary, CHO-P3R99, and Human Embryonic Kidney, HEK P3R99. While these variants have been shown to retain recognition to CS, the immunogenic capacity to produce Ab2 and Ab3 responses in-vivo are yet to be validated.
Hypothesis: Newly produced P3R99 variants will have a similar immunogenic response as the original NS0-P3R99 (chP3R99) in-vivo.
Objectives: To assess the immunogenic capacity of the PR399 variants compared to both a positive (NS0-P3R99) and negative (hR3) control in small and large animal models.
Methods/Results: Two studies were designed:
(i) Immunizations of 5-6 weekly doses of 200ug (HEK-P3R99, CHO-P3R99, NS0-P3R99, and HR3) in healthy lean JCR:LA-cp rats and swine.
(ii) Immunizations of 6 doses of 200ug of obese insulin-resistant JCR:LA-cp rats.
An Enzyme-Linked Immunosorbent Assay (ELISA) was then used to assess Ab2 and Ab3 antibodies in the pre-immune vs final dose sera. Both rats and pigs immunized with CHO-
P3R99 and HEK-P3R99s produced significant levels of Ab3 antibodies like that observed for the NS0-P3R99. However, in piglets, this response was independent of Ab2 antibody induction for the HEK-P3R99.
Conclusions: We demonstrate for the first time that the new P3R99 variants are not inferior in their capacity to induce anti-CS anti-atherogenic Ab3 antibodies through immunizations in rodents and swine.