B cell precursors are decreased in senescent mice, but retain normal mitotic activity in vivo and in vitro

We describe here the development and characterization of the FLS4.1 stromal line derived from 15-day fetal liver of BALB/c embryos and defined culture conditions that efficiently support the cloning and long-term growth of nontransformed B-220+ 14-day fetal liver cells at two stages of B-cell development, namely, pro-B lymphocytes (immunoglobulin [Ig] genes in germ line configuration) and pre-B cells (JH-rearranged genes with both light-chain Ig genes in the germ line state). All B-cell precursor clones require recombinant interleukin-7 (rIL-7) and FLS4.1 stromal cells for continuous growth in culture, but pro-B lymphocyte clones can also proliferate in rIL-3. None proliferate in rIL-1, rIL-2, rIL-4, rIL-5, rIL-6, or leukemia inhibitory factor. FLS4.1 stromal cells synthesize mRNA for Steel factor but not for IL-1 to IL-7; all pro-B and pre-B clones express c-Kit, the receptor for Steel factor, and a c-Kit-specific antibody inhibits the enhanced proliferative response of fetal liver B-220+ B-cell precursors supported by FLS4.1 stromal cells and exogenous rIL-7 but does not affect that promoted by rIL-7 alone. Northern (RNA) blot analysis of the expression of the MB-1, lambda 5, Vpre-B, c mu, RAG-1, and RAG-2 genes in pro-B and pre-B clones show that transcription of the MB-1 gene precedes IgH gene rearrangement and RNA synthesis from c mu, RAG-1, RAG-2, lambda 5, and Vpre-B genes. All clones at the pre-B-cell stage synthesize mRNA for c mu, RAG-1, and RAG-2 genes; transcription of the lambda 5 and Vpre-B genes seems to start after D-to-JH rearrangement in B-cell precursors, indicating that the proteins encoded by either gene are not required for B-cell progenitors to undergo D-to-JH gene rearrangement. These findings mark transcription of the MB-1 gene as one of the earliest molecular events in commitment to develop along the B-lymphocyte pathway. Indeed, both pro-B and pre-B clones can generate in vitro and in vivo B lymphocytes but not T lymphocytes; moreover, these clones do not express the CD3-gamma T-cell-specific gene, nor do they have rearranged gamma, delta, or beta T-cell antigen receptor genes.

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Hodgkin lymphoma cells express TACI and BCMA receptors and generate survival and proliferation signals in response to BAFF and APRIL

Blood ◽

10.1182/blood-2006-04-015958 ◽

2006 ◽

Vol 109 (2) ◽

pp. 729-739 ◽

Cited By ~ 133

Author(s):

April Chiu ◽

Weifeng Xu ◽

Bing He ◽

Stacey R. Dillon ◽

Jane A. Gross ◽

...

Keyword(s):

B Cells ◽

B Cell ◽

Hodgkin Lymphoma ◽

Myeloid Cells ◽

Small Interfering Rnas ◽

Cell Accumulation ◽

Germinal Center B Cell ◽

B Cell Precursors

Abstract Hodgkin lymphoma (HL) originates from the clonal expansion of malignant Hodgkin and Reed-Sternberg (HRS) cells. These B-cell–derived elements constitute less than 10% of the tumoral mass. The remaining tissue is comprised of an inflammatory infiltrate that includes myeloid cells. Myeloid cells activate B cells by producing BAFF and APRIL, which engage TACI, BCMA, and BAFF-R receptors on the B cells. Here, we studied the role of BAFF and APRIL in HL. Inflammatory and HRS cells from HL tumors expressed BAFF and APRIL. Unlike their putative germinal center B-cell precursors, HRS cells lacked BAFF-R, but expressed TACI and BCMA, a phenotype similar to that of plasmacytoid B cells. BAFF and APRIL enhanced HRS cell survival and proliferation by delivering nonredundant signals via TACI and BCMA receptors through both autocrine and paracrine pathways. These signals caused NF-κB activation; Bcl-2, Bcl-xL, and c-Myc up-regulation; and Bax down-regulation, and were amplified by APRIL-binding proteoglycans on HRS cells. Interruption of BAFF and APRIL signaling by TACI-Ig decoy receptor, which binds to and neutralizes BAFF and APRIL, or by small-interfering RNAs targeting BAFF, APRIL, TACI, and BCMA inhibited HRS cell accumulation in vitro and might attenuate HL expansion in vivo.

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In Vitro and in Vivo Anti-Leukemic Efficacy of Cyclic AMP Modulating Agents Against Human Leukemic B-cell Precursors

Leukemia & Lymphoma ◽

10.3109/10428199609051756 ◽

1996 ◽

Vol 22 (3-4) ◽

pp. 259-264 ◽

Cited By ~ 8

Author(s):

Dorothea E. Myers ◽

Mridula Chandan-Langlie ◽

Lisa M. Chelstrom ◽

Fatih M. Uckun

Keyword(s):

Cyclic Amp ◽

B Cell ◽

B Cell Precursors

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T-cell developmental blockage by tachykinin antagonists and the role of hemokinin 1 in T lymphopoiesis

Blood ◽

10.1182/blood-2002-11-3572 ◽

2003 ◽

Vol 102 (6) ◽

pp. 2165-2172 ◽

Cited By ~ 53

Author(s):

Yu Zhang ◽

Christopher J. Paige

Keyword(s):

T Cell ◽

B Cell ◽

T Cell Development ◽

Cell Development ◽

Double Positive ◽

Peptide Family ◽

Tachykinin Antagonists ◽

B Cell Precursors

Abstract Hemokinin 1 (HK-1) is a new member of the tachykinin peptide family that is expressed in hematopoietic cells. Recent reports studying mouse, rat, and human orthologs of HK-1 demonstrate a broader distribution than originally reported. Our previous studies demonstrated that HK-1, by promoting proliferation, survival, and possibly maturation of B-cell precursors, plays an important role in B lymphopoiesis. Here we present data showing that HK-1 also influences T-cell development at a similar stage of differentiation. This peptide enhanced the proliferation of T-cell precursors and increased the number of thymocytes in fetal thymus organ cultures (FTOCs). Tachykinin antagonists, on the other hand, greatly reduced the cellularity of thymi both in vivo and in vitro. The major reduction occurred in the CD4/CD8 double-positive (DP) cells and the CD44–CD25+ subset of the CD4/CD8 double-negative (DN) cells. Of note, these populations also express HK-1, raising the possibility of autocrine or paracrine pathways influencing T-cell development as we previously reported for B-cell development. Consistent with this, the detrimental effect of tachykinin antagonists could be partially overcome with exogenous HK-1 peptide.

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In vitro and in vivo chemosensitizing activity of LFM-A13, a dual-function inhibitor of Bruton's tyrosine kinase and polo-like kinases, against human leukemic B-cell precursors

Arzneimittelforschung ◽

10.1055/s-0031-1296196 ◽

2011 ◽

Vol 61 (04) ◽

pp. 252-259 ◽

Cited By ~ 5

Author(s):

Fatih Uckun ◽

Ilker Dibirdik ◽

Aniee Sarkissian ◽

Sanjive Qazi

Keyword(s):

Tyrosine Kinase ◽

B Cell ◽

Dual Function ◽

Bruton’S Tyrosine Kinase ◽

Bruton's Tyrosine Kinase ◽

B Cell Precursors

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A Patient-Derived Xenograft Model for Identifying Therapies and Defining Mechanisms of TSLP-Induced CRLF2 Signals in Ph-like B-ALL

Blood ◽

10.1182/blood.v126.23.2633.2633 ◽

2015 ◽

Vol 126 (23) ◽

pp. 2633-2633

Author(s):

Olivia L Francis ◽

Terry-Ann MIlford ◽

Ineavely Baez ◽

Jacqueline Coats ◽

Christopher L. Morris ◽

...

Keyword(s):

Gene Expression ◽

B Cell ◽

Mtor Pathway ◽

In Vivo Model ◽

In Vitro Production ◽

Pathway Activation ◽

B Cell Precursors ◽

Vitro Production

Abstract Philadelphia chromosome (Ph)-like B cell acute lymphoblastic leukemia (B-ALL) is a high-risk leukemia with a gene expression profile similar to BCR-ABL1+ B-ALL. Approximately 50% of all Ph-like B-ALL is characterized by genetic alterations leading to overexpression of CRLF2 (CRLF2 B-ALL). CRLF2 B-ALL occurs 5 times more often in Hispanic and Native American children than others and is prevalent in adolescents and young adults. The poor outcomes associated with CRLF2 B-ALL represent a major clinical challenge and an important component of pediatric cancer health disparities. Biologically, CRLF2 acts as a receptor component for the cytokine, TSLP, which induces JAK2-STAT5 and PI3/AKT/mTOR pathway activation downstream of binding to CRLF2. Activating JAK mutations are associated with CRLF2 B-ALL, but overall data indicate that JAK mutations are present in 50% or less of CRLF2 B-ALL. Our data show that normal primary human bone marrow (BM) stromal cells express TSLP, suggesting that TSLP-induced CRLF2 signals could play a role in the initiation, maintenance and progression of CRLF2 B-ALL, particularly in cases without JAK mutations. Consistent with this, TSLP has been reported to increase in vitro production of human fetal B cell precursors. However studies of TSLP in B lymphopoiesis have been conducted almost exclusively in mice which show low homology (~40%) to human TSLP and CRLF2. Further, using phospho flow cytometry we show that mouse TSLP is unable to induce increases in pSTAT5, pAKT and pS6 observed in CRLF2 B-ALL cells stimulated with human TSLP, confirming the species specificity of mouse TSLP. These findings underscore the importance and challenge of developing in vivo systems that can model human TSLP-CRLF2 interactions for evaluating therapies and studying leukemogenesis of CRRLF2 B-ALL. To address this challenge we engineered patient-derived xenograft (PDX) mice to produce human TSLP (hTSLP) by transplanting them with stromal cells transduced to express hTSLP (+T mice). Control (-T) mice were produced by transplanting with stroma transduced with a control vector. Supernatant from engineered +T stroma, but not -T stroma, induced JAK/STAT5 and PI3K/AKT/mTOR pathway activation in CRLF2 B-ALL cells. ELISA assays showed normal serum levels of hTSLP (12-32 pg/ml) in +T mice, while hTSLP was undetectable in -T mice. Since TSLP has been shown to increase in vitro production of human B cell precursors, we evaluated the in vivo functionality of our model by comparing the production of normal B cell precursors in the BM of +T and -T PDX mice generated with human umbilical cord blood CD34+ cells. Data from 3 different cord blood donors showed that production of B cell precursors is 3-5 fold increased in +T as compared to -T mice. TSLP-induced increases were specific to B lineage cells, initiated in the earliest CD19+ B cell precursors, and maintained through later stages of B cell development. Next we evaluate the in vivo functionality of our model using primary leukemia cells. +T and -T PDX mice were produced using primary CRLF2 B-ALL cells. BM was harvested and whole genome microarray was performed on isolated CRLF2 B-ALL cells. Evaluation of microarray data by Gene Set Enrichment Analysis (GSEA) and Ingenuity Pathway Analysis showed that genes downstream of mTOR pathway activation were upregulated in +T as compared to -T PDX mice, confirming hTSLP activity in the +T PDX mice. Next we tested whether +T PDX mice provide an in vivo model of B-ALL that more closely mirrors patients than -T PDX mice. +T and -T PDX mice were generated from primary high risk B-ALL. RNAseq gene expression profiles from primary patient B-ALL cells were compared to those of the same patient sample expanded in +T and -T PDX mice. The gene expression pattern in +T mice was significantly closer to the primary patient sample than those from -T mice. The +T and -T PDX mice described here provide a novel preclinical model for studying the role of TSLP in the initiation, progression and maintenance of CRLF2 B-ALL and for evaluating drug efficacy in an in vivo model that more closely mirrors the in vivo environment present in patients. Disclosures No relevant conflicts of interest to declare.

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Fetal liver pro-B and pre-B lymphocyte clones: expression of lymphoid-specific genes, surface markers, growth requirements, colonization of the bone marrow, and generation of B lymphocytes in vivo and in vitro.

Molecular and Cellular Biology ◽

10.1128/mcb.12.2.518 ◽

1992 ◽

Vol 12 (2) ◽

pp. 518-530 ◽

Cited By ~ 17

Author(s):

R Palacios ◽

J Samaridis

Keyword(s):

B Cell ◽

B Lymphocytes ◽

Stromal Cells ◽

B Lymphocyte ◽

Germ Line ◽

Fetal Liver ◽

Rag 1 ◽

B Cell Precursors

We describe here the development and characterization of the FLS4.1 stromal line derived from 15-day fetal liver of BALB/c embryos and defined culture conditions that efficiently support the cloning and long-term growth of nontransformed B-220+ 14-day fetal liver cells at two stages of B-cell development, namely, pro-B lymphocytes (immunoglobulin [Ig] genes in germ line configuration) and pre-B cells (JH-rearranged genes with both light-chain Ig genes in the germ line state). All B-cell precursor clones require recombinant interleukin-7 (rIL-7) and FLS4.1 stromal cells for continuous growth in culture, but pro-B lymphocyte clones can also proliferate in rIL-3. None proliferate in rIL-1, rIL-2, rIL-4, rIL-5, rIL-6, or leukemia inhibitory factor. FLS4.1 stromal cells synthesize mRNA for Steel factor but not for IL-1 to IL-7; all pro-B and pre-B clones express c-Kit, the receptor for Steel factor, and a c-Kit-specific antibody inhibits the enhanced proliferative response of fetal liver B-220+ B-cell precursors supported by FLS4.1 stromal cells and exogenous rIL-7 but does not affect that promoted by rIL-7 alone. Northern (RNA) blot analysis of the expression of the MB-1, lambda 5, Vpre-B, c mu, RAG-1, and RAG-2 genes in pro-B and pre-B clones show that transcription of the MB-1 gene precedes IgH gene rearrangement and RNA synthesis from c mu, RAG-1, RAG-2, lambda 5, and Vpre-B genes. All clones at the pre-B-cell stage synthesize mRNA for c mu, RAG-1, and RAG-2 genes; transcription of the lambda 5 and Vpre-B genes seems to start after D-to-JH rearrangement in B-cell precursors, indicating that the proteins encoded by either gene are not required for B-cell progenitors to undergo D-to-JH gene rearrangement. These findings mark transcription of the MB-1 gene as one of the earliest molecular events in commitment to develop along the B-lymphocyte pathway. Indeed, both pro-B and pre-B clones can generate in vitro and in vivo B lymphocytes but not T lymphocytes; moreover, these clones do not express the CD3-gamma T-cell-specific gene, nor do they have rearranged gamma, delta, or beta T-cell antigen receptor genes.

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Integrin α6 mediates the drug resistance of acute lymphoblastic B-cell leukemia

Blood ◽

10.1182/blood.2019001417 ◽

2020 ◽

Vol 136 (2) ◽

pp. 210-223 ◽

Cited By ~ 2

Author(s):

Eun Ji Gang ◽

Hye Na Kim ◽

Yao-Te Hsieh ◽

Yongsheng Ruan ◽

Heather A. Ogana ◽

...

Keyword(s):

Drug Resistance ◽

Tyrosine Kinase ◽

B Cell ◽

Kinase Inhibitor ◽

Residual Disease ◽

Lymphoblastic Leukemia ◽

Underlying Mechanism ◽

Conditional Knockout

Abstract Resistance to multimodal chemotherapy continues to limit the prognosis of acute lymphoblastic leukemia (ALL). This occurs in part through a process called adhesion-mediated drug resistance, which depends on ALL cell adhesion to the stroma through adhesion molecules, including integrins. Integrin α6 has been implicated in minimal residual disease in ALL and in the migration of ALL cells to the central nervous system. However, it has not been evaluated in the context of chemotherapeutic resistance. Here, we show that the anti-human α6-blocking Ab P5G10 induces apoptosis in primary ALL cells in vitro and sensitizes primary ALL cells to chemotherapy or tyrosine kinase inhibition in vitro and in vivo. We further analyzed the underlying mechanism of α6-associated apoptosis using a conditional knockout model of α6 in murine BCR-ABL1+ B-cell ALL cells and showed that α6-deficient ALL cells underwent apoptosis. In vivo deletion of α6 in combination with tyrosine kinase inhibitor (TKI) treatment was more effective in eradicating ALL than treatment with a TKI (nilotinib) alone. Proteomic analysis revealed that α6 deletion in murine ALL was associated with changes in Src signaling, including the upregulation of phosphorylated Lyn (pTyr507) and Fyn (pTyr530). Thus, our data support α6 as a novel therapeutic target for ALL.

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Dual Role of Interleukin-10 in Murine NZB/W F1 Lupus

International Journal of Molecular Sciences ◽

10.3390/ijms22031347 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1347

Author(s):

Anaïs Amend ◽

Natalie Wickli ◽

Anna-Lena Schäfer ◽

Dalina T. L. Sprenger ◽

Rudolf A. Manz ◽

...

Keyword(s):

B Cell ◽

Disease Model ◽

Interleukin 10 ◽

Immune Functions ◽

Murine Lupus ◽

Anti Inflammatory ◽

In Vivo Effects

As a key anti-inflammatory cytokine, IL-10 is crucial in preventing inflammatory and autoimmune diseases. However, in human and murine lupus, its role remains controversial. Our aim was to understand regulation and immunologic effects of IL-10 on different immune functions in the setting of lupus. This was explored in lupus-prone NZB/W F1 mice in vitro and vivo to understand IL-10 effects on individual immune cells as well as in the complex in vivo setting. We found pleiotropic IL-10 expression that largely increased with progressing lupus, while IL-10 receptor (IL-10R) levels remained relatively stable. In vitro experiments revealed pro- and anti-inflammatory IL-10 effects. Particularly, IL-10 decreased pro-inflammatory cytokines and slowed B cell proliferation, thereby triggering plasma cell differentiation. The frequent co-expression of ICOS, IL-21 and cMAF suggests that IL-10-producing CD4 T cells are important B cell helpers in this context. In vitro and in vivo effects of IL-10 were not fully concordant. In vivo IL-10R blockade slightly accelerated clinical lupus manifestations and immune dysregulation. Altogether, our side-by-side in vitro and in vivo comparison of the influence of IL-10 on different aspects of immunity shows that IL-10 has dual effects. Our results further reveal that the overall outcome may depend on the interplay of different factors such as target cell, inflammatory and stimulatory microenvironment, disease model and state. A comprehensive understanding of such influences is important to exploit IL-10 as a therapeutic target.

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