Phenotypes Associated with This Genotype

Genotype
MGI:3700262

• Allelic Composition: Ighm^tm1Cgn/Ighm^tm1Cgn
• Genetic Background: B6.129S2-Ighm^tm1Cgn/J

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

immune system

immune system phenotype ( J:73100 , J:118565 )

N • T cell numbers in lymph nodes are normal (J:73100)

N • dendritic cells show normal function in mutants (J:118565)

arrested B cell differentiation ( J:119584 )

• a transitional block in early B cell development in evident in bone marrow; pre-B cells are decreased in number

decreased dendritic cell number ( J:73100 )

• numbers of CD11c+ dendritic cells (DCs) are reduced in mutants

decreased CD4-positive, alpha-beta T cell number ( J:73100 , J:118565 )

• numbers are reduced 3-fold in spleen vs wild-type (J:73100)

• there are 5- to 40-fold fewer antigen specific CD4 cells producing Il-2 in mutants compared to controls 6 months after keyhole limpet hemocyanin immunization (J:118565)

decreased CD8-positive, alpha-beta T cell number ( J:73100 )

• numbers are reduced 3-fold in spleen vs wild-type

abnormal spleen morphology ( J:73100 )

• in mutants, area of T zone stromal cell network in the spleen is decreased four- to five-fold compared to wild-type

• T zone cross sectional area is decreased 2- to 3-fold

decreased spleen weight ( J:73100 )

• spleens are ~50% the weight of wild-type spleens

abnormal humoral immune response ( J:119584 )

• mice fail to respond to T cell-dependent (OVA) or T cell-independent (dextra) antigenic stimulation and do not produce serum specific antibodies to these antigens

decreased immunoglobulin level ( J:119584 )

• null mice have almost undetectable serum levels of IgG1, IgG2a, IgG2b, IgG3, IgM and IgA compared to wild-type controls or Fas^lpr mice

decreased IgE level ( J:125656 )

• IgE is not detectable in serum of OVA-treated mutants, but high levels are produced in treated wild-type

decreased IgG level ( J:119584 , J:125656 )

• IgG levels drop rapidly after birth due to loss of maternal Ig (J:119584)

• IgG is not detectable in OVA-treated mutants, but high levels are produced in treated wild-type (J:125656)

decreased IgG1 level ( J:125656 )

• IgG1 is not detected in serum after OVA challenge

abnormal cytokine secretion ( J:118565 )

• in mutants, Il-2 secretion is diminished from T cells primed in absence of B cells compared to controls 6 months after keyhole limpet hemocyanin immunization

increased susceptibility to parasitic infection ( J:74568 )

• mice fail to clear a Giardia muris infection

• two weeks after Giardia infection, there are 10-fold more Giardia cysts present in the feces of mice

• mice have 10-fold more Giardia trophozoites in the small intestine three weeks after infection and a thousand-fold more 7 weeks after infection compared to controls

• mutant mice still have an active Giardia population in the gut one year after infection while wild-type mice clear Giardia after about 7 weeks

• mice are not protected from Giardia upon a secondary challenge as wild-type mice are

hematopoietic system

arrested B cell differentiation ( J:119584 )

• a transitional block in early B cell development in evident in bone marrow; pre-B cells are decreased in number

decreased dendritic cell number ( J:73100 )

• numbers of CD11c+ dendritic cells (DCs) are reduced in mutants

decreased CD4-positive, alpha-beta T cell number ( J:73100 , J:118565 )

• numbers are reduced 3-fold in spleen vs wild-type (J:73100)

• there are 5- to 40-fold fewer antigen specific CD4 cells producing Il-2 in mutants compared to controls 6 months after keyhole limpet hemocyanin immunization (J:118565)

decreased CD8-positive, alpha-beta T cell number ( J:73100 )

• numbers are reduced 3-fold in spleen vs wild-type

abnormal spleen morphology ( J:73100 )

• in mutants, area of T zone stromal cell network in the spleen is decreased four- to five-fold compared to wild-type

• T zone cross sectional area is decreased 2- to 3-fold

decreased spleen weight ( J:73100 )

• spleens are ~50% the weight of wild-type spleens

decreased immunoglobulin level ( J:119584 )

• null mice have almost undetectable serum levels of IgG1, IgG2a, IgG2b, IgG3, IgM and IgA compared to wild-type controls or Fas^lpr mice

decreased IgE level ( J:125656 )

• IgE is not detectable in serum of OVA-treated mutants, but high levels are produced in treated wild-type

decreased IgG level ( J:119584 , J:125656 )

• IgG levels drop rapidly after birth due to loss of maternal Ig (J:119584)

• IgG is not detectable in OVA-treated mutants, but high levels are produced in treated wild-type (J:125656)

decreased IgG1 level ( J:125656 )

• IgG1 is not detected in serum after OVA challenge

respiratory system

abnormal respiratory system physiology ( J:125656 )

• ovalbumin-sensitized/challenged mice (OVA) are unable to generate an early phase reaction (EPR- initial phase of brochoconstriction) following OVA provocation

cardiovascular system

abnormal cardiovascular system physiology ( J:182612 )

• mutants are protected from developing elastase-induced abdominal aortic aneurysm

homeostasis/metabolism

decreased susceptibility to injury ( J:182612 )

• mutants are protected from developing elastase-induced abdominal aortic aneurysm

• reconstitution of mutants with mouse natural antibodies from pooled sera of wild-type mice does not restore susceptibility to abdominal aortic aneurysm in mutants, however reconstitution with pooled mouse IgG to the wild-type level renders mutants susceptible to abdominal aortic aneurysm

skeleton

decreased bone mineral density ( J:145330 )

• significantly decreased at 10 weeks of age

abnormal compact bone morphology ( J:145330 )

decreased compact bone volume ( J:145330 )

decreased compact bone thickness ( J:145330 )

abnormal trabecular bone morphology ( J:145330 )

• reduced trabecular bone structure in femora

• reduced number of trabeculae

decreased trabecular bone thickness ( J:145330 )