Property and Equipment
 12 Months Ended
Dec. 31, 2021
Property, Plant and Equipment [Abstract]  
Property and Equipment Property and Equipment
Property and equipment consists of the following (in thousands):
 December 31,
 20212020
Laboratory equipment$5,134 $4,427 
Computer equipment and software731 532 
Leasehold improvements45 38 
Furniture and fixtures332 327 
Office equipment163 163 
Construction in process534 163 
Total property and equipment6,939 5,650 
Less accumulated depreciation(4,797)(4,255)
Property and equipment, net$2,142 $1,395 

Depreciation expense was $0.6 million, $0.6 million and $0.7 million for the years ended December 31, 2021, 2020 and
2019, respectively.