Index: class-wp-list-table.php
===================================================================
--- class-wp-list-table.php	(revision 37370)
+++ class-wp-list-table.php	(working copy)
@@ -686,6 +686,12 @@
 				$approved_comments ? __( 'No pending comments' ) : __( 'No comments' )
 			);
 		}
+		// If comments are closed, show a lock then
+		if ( ! comments_open( $post_id ) ) {
+			printf( '<span aria-hidden="true"><span class="dashicons dashicons-lock"></span></span><span class="screen-reader-text">%s</span>',
+				__( 'Comments are closed' )
+			);
+		}		
 	}
 
 	/**