Characterization of memory B cells responsible for affinity maturation of anti- (4-hydroxy-3-nitrophenyl)acetyl (NP) antibodies.
Int Immunol
; 23(4): 271-85, 2011 Apr.
Article
en En
| MEDLINE
| ID: mdl-21421736
We searched for memory B cells responsible for high-affinity anti-(4-hydroxy-3-nitrophenyl)acetyl (NP) antibody production by C57BL/6 mice immunized with NP-chicken γ-globulin (CGG), using flow cytometry. We first prepared transfectants expressing B-cell antigen receptor (BCR) of known affinity as a memory B-cell model as well as NP-allophycocyanin (APC) of different NP valences, NP(lo), NP(med) and NP(hi). We then used the latter as probes capable of distinguishing BCR affinities: NP(lo)-APC bound to BCRs with an affinity higher than 3.4 × 10(6) M(-1), while NP(med)-APC bound to those with a higher than germline affinity. B cells capable of binding to NP(lo)-APC appeared in spleens on day 14 post-immunization, and harbored Tyr95 (Tyr95 type) as well as a mutation from Trp33 to Leu. B cells with BCRs harboring Gly95 (Gly95 type) appeared only in the NP(med)-APC-binding fraction on day 56 and in the NP(lo)-APC-binding fraction on day 77, indicating that this long duration was necessary for Gly95 type B cells to acquire high affinity and to become a member of the group of memory B cells with high affinity. Administration of NP-CGG on day 77 caused little change in the proportion of the Gly95 type in NP(lo)-APC-binding B cells in the following 2 weeks but brought about an increase in the number of high-affinity antibody-secreting cells (ASC), suggesting that the memory B-cell compartment established was maintained at a later stage and supplied high-affinity ASCs. The relationship between these Gly95 type memory B cells and ASCs is discussed.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Linfocitos B
/
Receptores de Antígenos de Linfocitos B
/
Anticuerpos
Límite:
Animals
Idioma:
En
Revista:
Int Immunol
Asunto de la revista:
ALERGIA E IMUNOLOGIA
Año:
2011
Tipo del documento:
Article
País de afiliación:
Japón
Pais de publicación:
Reino Unido