Biochemical and functional analysis of mice deficient in expression of the CD45-associated phosphoprotein LPAP.
The role of the CD45-associated phosphoprotein (LPAP / CD45-AP) during an immune response remains unclear. To understand better the function of LPAP we generated LPAP-deficient mice by disrupting exon 2 of the LPAP gene. LPAP-null mice were healthy and did not show gross abnormalities compared to their wild-type littermates. However, immunofluorescence analysis of T and B lymphocytes revealed a reduced expression of CD45, which did not affect a particular subpopulation. In contrast to a recent report (Matsuda et al., J. Exp. Med. 1998. 187: 1863 - 1870) we neither observed significant alterations of the assembly of the CD45 / lck-complex nor of polyclonal T-cell responses. However, lymphnodes from LPAP-null mice showed increased cellularity, which could indicate that expression of LPAP might be required to prevent expansion of lymphocytes in particular lymphatic organs rather than potentiating immune responses.
Ding
I
I
Immunomodulation Laboratory of the Institute for Immunology University of Heidelberg, Heidelberg, Germany.
Bruyns
E
E
Li
P
P
Magada
D
D
Paskind
M
M
Rodman
L
L
Seshadri
T
T
Alexander
D
D
Giese
T
T
Schraven
B
B
D000818:Animals; D005786:Gene Expression Regulation / Q000276:immunology*; D047908:Intracellular Signaling Peptides and Proteins; D017493:Leukocyte Common Antigens / Q000235:genetics / Q000276:immunology*; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology; D008565:Membrane Proteins; D051379:Mice; D018345:Mice, Knockout; D010750:Phosphoproteins / Q000235:genetics* / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D010750:Phosphoproteins; C513303:Ptprcap protein, mouse; D017493:Leukocyte Common Antigens