Table 1.

Comparison of zebrafish embryos and mice as models for leukocyte migration

	Mice	Zebrafish embryos
General
Degree of conservation compared with humans	Mammalian	Vertebrate
Optical clarity	−	+
In vivo image resolution	Cellular	Molecular
Cost to maintain	High	Low
Generation time	3 months	3–6 months
Number of animals used for each experiment	Small	Large
Fully sequenced genome	+	+
Developmental stage	Various	Embryonic
Inbred strains	+	−
Genome duplication	−	+
Leukocytes
Accurate model of human hematopoiesis	+	+
Well-characterized immune system	+	+/−
Conserved innate immune system	+	+
Presence of adaptive immunity	+	−
Suitable model for leukocyte random motility	−	+
Suitable model for leukocyte transmigration	+	+
Suitable model for leukocyte interstitial migration	+/−	+
Tools
Use of MO for transient gene depletion	−	+
Reverse genetics	Knock-out, knock-in, tissue-specific knockout, inducible system	TALENs, ZFNs, knock-in, tissue-specific knockdown, inducible system
Forward genetics	+	+/gynogenetic diploid screen
Large-scale WISH screens	+/−	+
In vivo chemical screens	−	+
Administration of blocking antibodies	i.v.	Limited antibodies available

TALENs, TAL effector nucleases; WISH, whole-mount in situ hybridization; ZFN, zinc-finger nucleases; i.v., intravenous; +, yes; −, no.