Table 1.

Comparison of the phenotypes of Fcmr^−/− mice generated/analyzed by different groups.

Mouse strain		Fcmrtm1Ohno		Fcmrtm1Mak		Fcmrtm1.2Khl	Fcmrflx/flx CD19-Cre+
Targeting strategy		Exons 2–4 were deleted in 129/Sv ES cells and the mice backcrossed to C57BL/6 mice. The neo gene was removed		Exons 2–8 were deleted in 129/Sv ES cells and the mice backcrossed to C57BL/6 mice. The neo gene was not removed		Constitutive FcμR knockout strain and a conditional knockout with exons 4–7 deleted. Pure B6 background	Exon 4 was deleted by CD19-driven Cre. Pure B6 background
Research group		Hiromi Kubagawa	Ji-Yang Wang	John E. Coligan	Tak W. Mak	Kyeong-Hee Lee	Nicole Baumgarth
Related references		(32, 41)	(27, 28, 40)	(31)	(29, 30, 44)	(45, 47)	(33, 48)
B & T cells	BM	Pro-B, Pre-B, Immature B, Recirculating B	Pro-B, Pre-B, Immature B, Recirculating B	Pro-B, Pre-B, Immature B, Recirculating B			Pro-B, Pre-B, Immature B, Recirculating B, $\text{B}1$
	Spleen	Total T, Total B, FOB, Newly formed B, $\text{Regulatory B, MZB}$, $\text{B}1$	Total T, Total B, FOB, $\text{T3, MZB}$	Total B, Newly formed B, Regulatory B, MZB, B1, $\text{FOB}$		Total T, $\text{Mature B}$, $\text{Newly formed B, Regulatory B, MZB, B1a}$,	Total B, $\text{FOB number}$, Newly formed B, MZB number, $\text{MZB ratio}$, $\text{B1, B1a, GCB}$
	PC	$\text{Total T}$, Total B, B1a, B1b, B2	B1a	$\text{Total B, B1a}$, B1b, $\text{B}2$		$\text{B1a}$, $\text{B1b}$
B cell function			BCR-triggered Ca2+ influx, antigen presentation, CSR, $\text{B cell survival induced by BCR cross-linking, BCR-triggered activation of non-canonical NF-κB pathway}$	B cell survival induced by BCR cross-linking		B cell activation	Turnover and survival of B cells
Homeostasis & Humoral immune responses	Basal Ig levels	IgG2b, IgG2c, IgA, $\text{IgM, IgG3}$	IgG3, IgG2b IgG2c, IgA, $\text{IgM}$	3 month old: IgM, IgG3, IgG2b IgG2a, IgA, $\text{IgG}1$; 6 month old: IgM, IgG1, IgG2b IgG2a, $\text{IgG3, IgA}$			IgG, IgA, $\text{IgM}$
	TI response	Phosphorylcholine response	TI-1 & TI-2 responses, MZB response to LPS	GCB & PC	Response to LPS
	TD response	Affinity maturation of Abs, $\text{primary IgG1 and secondary IgM anti-CGG responses}$	GC formation, Memory B and plasma cell, Ab production in primary and secondary responses	GCB, $\text{PC, IgM}$, $\text{IgG2a}$
Infectious immunity		Low dose of R36A: $\text{increased IgM and IgG3 responses}$; High dose of R36A: no increase	C. rodentium-induced sepsis		Listeria-induced & persistence-prone infection	TNFα-mediated liver damage, Influenza virus infection	Influenza virus infection
B cell tolerance		$\text{IgM and IgG anti-dsDNA, ANAs; Serum auto-antibody titers and Mott cell formation in FcμR KO B6/lpr mice}$ but no lupus-like nephritis	IgG anti-dsDNA Abs, rheumatoid factor, ANAs	IgG anti-dsDNA and ANAs	EAE	$\text{Differentiation/maintenance of regulatory B cells}$, $\text{IgM an IgG anti-dsDNA, or anti-ssDNA}$	IgM and IgG anti-dsDNA

Black: not affected.

$Blue:increasedorenhanced.$

$Red:decreasedorimpaired.$

Blank: not investigated.