Focused Ultrasound Improves NK-92MI Cells Infiltration Into Tumors

Area of Science:

• Oncology
• Immunotherapy
• Biomedical Engineering

Background:

• Adoptively transferred natural killer (NK) cells face challenges in solid tumor treatment, including poor tumor infiltration and limited viability without IL-2.
• Genetically modified NK-92MI cells can self-sustain viability via IL-2 release, mitigating risks of exogenous IL-2 administration.

Purpose of the Study:

• To evaluate if focused ultrasound (FUS) combined with microbubbles enhances NK-92MI cell infiltration into ovarian tumors.
• To explore the therapeutic effects and potential molecular mechanisms of this FUS-assisted NK cell therapy.

Main Methods:

• Utilized biodistribution, immunofluorescence, and flow cytometry to assess NK-92MI cell infiltration.
• Administered FUS and microbubbles twice weekly in combination with NK-92MI cells.
• Investigated molecular mechanisms by evaluating ICAM1 and CX3CL1 expression using qRT-PCR.

Main Results:

• FUS and microbubbles significantly improved NK-92MI cell infiltration into ovarian tumors.
• The combination of FUS and NK-92MI cells showed improved treatment effects compared to the PBS control group.
• CX3CL1 expression was identified as potentially involved in FUS-assisted NK cell infiltration.

Conclusions:

• FUS and microbubbles can enhance the infiltration of adoptively transferred NK-92MI cells into solid tumors.
• The current FUS-assisted strategy requires further optimization to achieve a clinically relevant therapeutic benefit.
• CX3CL1 may play a role in facilitating NK cell homing to tumors under FUS treatment.