• 미생물과산업
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• 제16권3호
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• pp.2-5
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• 1990

IgA is the predominant immunoglobulin isotype in mucosal secretions(1). It has been reported that a population of Peyer's patch T cells can selectively induce IgM bearing B cells to switch to surface IgA bearing B cells(2,3). Further, IL-4, IL-5, and IL-6 alone and in combination, can significantly influence murine IgA B cell differentiation in vitro(4-7). However, it remains an open question which cytokines have a major role in class switching to the IgA isotype. Recently, it has been reported that transforming growth factor .betha.1(TGF .betha.1) alone, or in combination with IL-2 increases IgA secretion by LPS-activated surface IgA negative (sIgA$\^$-/) murine spleen B cells while concurrently downregulating IgM and IgG secretion by such cells(8-11). In the present study, limiting dilution analysis was used to demonstrate, at the clonal level, that TGF .betha.1 has siginificant activity as an IgA isotype switch factor.

• 한국식품영양과학회지
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• 제33권2호
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• pp.271-277
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• 2004

최근에 방사선 조사에 대해 방호효과를 가지는 것으로 알려진 보중익기탕의 골수세포 분화 유도 효과에 대해 관찰하였다. 시험관에서 골수세포를 배양했을 때, 배양시간(5일,10일)에 따라 대조군의 세포 수는 현저히 감소하였고, 보중익기 탕의 total 분획을 첨가하였을 때도 비슷한 결과를 얻었다. 그러나 polysaccaride 분획을 첨가하였을 때는 감소하는 세포수가 일정한수준에서 유지되며 더 이상 감노하지 않았다. 그리고 이들 세포가 어떤 종류의 세포인지를 유세포분석기로 분석한 결과, Pre-B세포의 특징적인 세포 표면 단백질인 CDl9와 CD40을 동시에 발현한 세포인 것이 확인되었다. 또한, 이들 세포는 분화과정 이 끝난 B세포가 분비하는 IgM 뿐만 아니라 IgG1, G2a, G3를 분비하였다. 이상의 결과 보중익기탕의 polysaccaride 분획에 골수세포가 B세포로 분화 증식하는 것을 유도하는 성분이 포함되어 있어 방사선 조사로 상해를 입은 조혈계에 대한 방호 효과를 나타내는 것으로 생각된다.

• IMMUNE NETWORK
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• 제20권5호
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• pp.42.1-42.10
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• 2020

Long-lasting post-switched plasma cells (PCs) arise mainly from germinal center (GC) reactions, but little is known about the mechanism by which GC B cells differentiate into PCs. Based on our observation that the expression of the transcription factor CCAAT/enhancer binding protein β (C/EPBβ) is associated with the emergence of post-switched PCs, we enquired whether a cell-autonomous function of C/EPBβ is involved in the program for PC development. To address this, we generated C/EPBβ-deficient mice in which the Cebpb locus was specifically deleted in B cells after transcription of the Ig γ1 constant gene segment (Cγ1). In response to in vitro stimulation, B cells from these Cebpb^fl/flCγ1^Cre/+ mice had defects in the induction of B lymphocyte-induced maturation protein 1 (Blimp1) and the formation of IgG1⁺ PCs, but not in proliferation and survival. At steady state, the Cebpb^fl/flCγ1^Cre/+ mice had reduced serum IgG1 titers but normal IgG2c and IgM titers. Moreover, upon immunization with T-dependent Ag, the mice produced reduced levels of Ag-specific IgG1 Ab, and were defective in the production of Ag-specific IgG1 Ab-secreting cells. These results suggest that a cell-autonomous function of C/EPBβ is crucial for differentiation of post-switched GC B cells into PCs through a Blimp1-dependent pathway.