Therapeutic Plasma Exchange Patients Cell Surface Proteins Plasmas

Overview

About this study

The purpose of this study is to determine if therapeutic plasma exchange (TPE) can reduce cell surface proteins circulating in plasma, including soluble receptors and extracellular vesicles (EVs).

 

 

 

 

 

Background:

Proteins expressed on the tumor surface are the focus of many targeted therapies, including antibody-based treatments, antibody-drug conjugates (ADCs), T cell receptor (TCR) fusion constructs, and chimeric antigen receptor T-cell (CAR-T) products. These target proteins can be shed from the tumor surface into the plasma as a soluble receptor or an EV, which may prevent targeted treatments from reaching the tumor. High levels of soluble MSLN (sMSLN) is associated with poor clinical outcomes in mesothelioma. Additionally, sMSLN and EV-positive (EV+) MSLN can interfere with MSLN targeted immunotoxins, ADCs, and CAR-T. Similar findings are seen with elevated levels of soluble PDL1, BCMA, and LAG3.

We recently reported that TPE decreases soluble PD-L1 (sPDL1) and PDL1-positive EVs. TPE is a routine procedure indicated in several medical conditions, including certain autoimmune disease and hyperviscosity syndromes, where the patient’s blood is removed, the plasma is separated out, then this plasma is exchanged with replacement fluid to give back to the patient. The procedure reliably removes proteins in the plasma that are larger than albumin (65-70 kDa), but is known to remove smaller substances as well. These results have culminated in a clinical trial to understand if using TPE to decrease circulating PD-L1 can restore anti-cancer immunity in patients with metastatic melanoma treated with immune checkpoint inhibitors (ICIs). Based on these findings, we hypothesized that TPE could similarly reduce sMSLN. We used 16 patient samples from the sPDL1 project in a feasibility study to determine if TPE could reduce sMSLN [6]. Our results show that TPE does reduce sMSLN (p <0.001).

 

Our sPDL1 and sMSLN results suggest that TPE can reduce these circulating proteins, which contribute to targeted therapy resistance. These findings may apply to other cell surface proteins as well. Our study aims to address a critical gap in our understanding of the soluble receptors and EVs present in the plasma, and whether TPE can significantly reduce these circulating proteins.

 

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Patients undergoing routine TPE for any medical condition.

Exclusion Criteria: 

  • Patients unwilling to consent for blood sample collection before and after a TPE session

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Eligibility last updated 12/21/23. Questions regarding updates should be directed to the study team contact.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Aaron Mansfield, M.D.

Contact us for the latest status

Contact information:

Katherine Smith

5072930569

smith.katherine3@mayo.edu

More information

Publications

Publications are currently not available