Phenotypes Associated with This Genotype

Genotype
MGI:4430083

• Allelic Composition: Spib^tm1Mcs/Spib^tm1Mcs
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ

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

immune system

increased B cell apoptosis ( J:45245 )

• increase in apoptosis of splenic B cells after immunization

decreased B cell proliferation ( J:45245 )

• B cells proliferate poorly and die in response to IgM stimulation, but respond normally to lipopolysaccharide stimulation

abnormal spleen white pulp morphology ( J:45245 )

• follicular zonation separating the germinal center, mantle zone and marginal zone are abnormal

abnormal spleen B cell follicle morphology ( J:45245 )

• following T-dependent antigenic challenge, spleens contain more B220+ B cells outside of the white pulp, indicating deterioration of the follicular organization

abnormal spleen germinal center morphology ( J:45245 )

• mutants fail to maintain their germinal centers following T-dependent antigenic challenge; germinal centers are smaller and are mostly eliminated as early as 21 days after antigenic challenge with increased numbers of apoptotic B cells

abnormal humoral immune response ( J:45245 )

• abnormal humoral immune responses to DNP-KLH

decreased IgG1 level ( J:45245 )

• secondary responses to T-dependent antigen show 3- to 5-fold lower levels of IgG1 8 days after reimmunization

decreased IgG2a level ( J:45245 )

• mutants immunized with a T-dependent antigen have lower serum antigen-specific IgG2a levels

• secondary responses show a 35-fold reduction in IgG2a levels after reimmunization

decreased IgG2b level ( J:45245 )

• secondary responses to T-dependent antigen show a 35-fold reduction in IgG2b levels 8 days after reimmunization

increased IgM level ( J:45245 )

• mutants immunized with a T-dependent antigen have 14-fold higher serum antigen-specific IgM levels

hematopoietic system

increased B cell apoptosis ( J:45245 )

• increase in apoptosis of splenic B cells after immunization

decreased B cell proliferation ( J:45245 )

• B cells proliferate poorly and die in response to IgM stimulation, but respond normally to lipopolysaccharide stimulation

abnormal spleen white pulp morphology ( J:45245 )

• follicular zonation separating the germinal center, mantle zone and marginal zone are abnormal

abnormal spleen B cell follicle morphology ( J:45245 )

• following T-dependent antigenic challenge, spleens contain more B220+ B cells outside of the white pulp, indicating deterioration of the follicular organization

abnormal spleen germinal center morphology ( J:45245 )

• mutants fail to maintain their germinal centers following T-dependent antigenic challenge; germinal centers are smaller and are mostly eliminated as early as 21 days after antigenic challenge with increased numbers of apoptotic B cells

decreased IgG1 level ( J:45245 )

• secondary responses to T-dependent antigen show 3- to 5-fold lower levels of IgG1 8 days after reimmunization

decreased IgG2a level ( J:45245 )

• mutants immunized with a T-dependent antigen have lower serum antigen-specific IgG2a levels

• secondary responses show a 35-fold reduction in IgG2a levels after reimmunization

decreased IgG2b level ( J:45245 )

• secondary responses to T-dependent antigen show a 35-fold reduction in IgG2b levels 8 days after reimmunization

increased IgM level ( J:45245 )

• mutants immunized with a T-dependent antigen have 14-fold higher serum antigen-specific IgM levels

cellular

increased B cell apoptosis ( J:45245 )

• increase in apoptosis of splenic B cells after immunization

decreased B cell proliferation ( J:45245 )

• B cells proliferate poorly and die in response to IgM stimulation, but respond normally to lipopolysaccharide stimulation