Uncovering Haematopoietic System Dynamics and Single Multipotent Progenitors Activity In Vivo In Humans by Retroviral Tagging.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2611-2611
Author(s):  
Luca Biasco ◽  
Cristina Baricordi ◽  
Stefania Merella ◽  
Cynthia Bartholomae ◽  
Alessandro Ambrosi ◽  
...  
Keyword(s):  
T Cell ◽  
B Cells ◽  
Human Model ◽  
The Real ◽  
Multipotent Progenitors ◽  
Cd34 Cells ◽  
Cell Subpopulations ◽  
T Cell Subpopulations

Abstract Abstract 2611 The long-standing model of human haematopoiesis postulates that myeloid and lymphoid lineages branch separately at very early stages, producing myeloid or erythroid cells and T or B cells, respectively. Conversely, a revised scheme of haematopoietic hierarchy was recently proposed, in which myeloid cells represent a prototype of blood cells, while erythroid, T and B cells are specialized cell types. The validity of these models has been mainly tested in vivo in the mouse, and in vitro through clonal assays on human haemopoietic stem cells (HSC). However, a clear definitive elucidation of the real nature of human haemopoiesis should ideally involve the ability to track the dynamics, survival and differentiation potential of haemopoietic progenitor clones for a long period of time directly in vivo in humans. Upon retroviral gene transfer, transduced cells are univocally tagged by vector insertions allowing them to be distinguished and tracked in vivo by integration profiling. We previously showed that gene therapy (GT) for adenosine deaminase (ADA) deficient SCID based on infusion of transduced CD34+ cells and reduced intensity conditioning, resulted in full multilineage engraftment, in the absence of aberrant expansions. Therefore, long-term studies in these patients provide a unique human model to study in depth haemopoietic clonal dynamics by retroviral tagging. For this reason, we performed a comprehensive multilineage longitudinal insertion profile of bone marrow (BM) (CD34+, CD15+, CD19+, Glycophorin+) and peripheral blood (PB) (CD15+, CD19+, CD4+, CD8+ cells, naïve and memory T cell subpopulations) cells in 4 patients 3–6 years after GT, retrieving to date 1055 and 1999 insertions from BM and PB cell lineages respectively. We could shape the insertional landscape of each lineage through a tri-factorial analysis based on the number of integrations retrieved, the percentage of vector positive cells and the number of insertion shared with other lineages. We were able to uncover the effects of selective advantages of gene-corrected cells in periphery and the frequency of identical integrants in different haematopoietic compartments. BM cells displayed the highest proportion of shared integrants (up to 58.1%), reflecting the real-time repopulating activity of gene-corrected progenitors. On the other hand, PB samples carried in general a higher frequency of vector positive cells, with the exception of PB CD15+ cells showing insertional landscapes very similar to the one of BM lineages. Interestingly, the detection of exclusively shared myeloid-T\B or myeloid-erythroid integrants may be supportive of a myeloid-based haemopoiesis model. We also uncovered “core integrants”, shared between CD34+ cells and both lymphoid and myeloid lineages, stably tagging active long-term multipotent progenitors overtime. Strikingly, one of these progenitor clones carried an insertion inside one of the two fragile sites of MLLT3 gene, involved by translocation events in mixed lineage leukemia. We were able to track this and another integrant (downstream the LRRC30 gene) by specific PCRs, confirming the multilineage contribution to haematopoiesis of the relative progenitor clones and their fluctuating lineage outputs over 4 years, without showing aberrant expansions. We also retrieved 170 and 174 integrations from 4 T cell subtypes (Naive, TEMRA, Central and Effector memory) in two patients under PBL-GT and HSC-GT respectively. We found evidences that single naive T cell clones may survive in patients for up to 10 years after last infusion while maintaining their differentiation capacity into different T cell subpopulations. Interestingly, a cluster of 4 insertions (one of them shared among all T cell subtypes) was found in proximity of the interferon regulatory factor 2 binding protein 2 (IRF2BP2) gene in naive T cells from PBL-GT patient, thus suggesting an influence of transcriptional activity of this region on selective advantage of gene-corrected lymphocytes. In conclusion, through retroviral tagging, we can uniquely track single transduced haemopoietic cells directly in vivo in humans. The application of mathematical models to our insertion datasets is allowing to uncover new information on the fate and activity of haematopoietic progenitors and their differentiated progeny years after transplantation in GT patients. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Disproportion in T-cell subpopulations in immunodeficient mutant hr/hr mice.

1979 ◽  
Vol 149 (1) ◽  
pp. 228-233 ◽  
Author(s):  
A B Reske-Kunz ◽  
M P Scheid ◽  
E A Boyse
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Lymph Nodes ◽  
Salient Feature ◽  
Mutant Gene ◽  
Cell Subpopulations ◽  
T Cell Subpopulations

Mice of the HRS strain, which carry the mutant gene hr, were examined for abnormalities in representation of the three T-cell sets Ly1, Ly23, and Ly123 in the spleen. The salient feature of hr/hr mice, which are immunologically deficient, in comparison with +/hr segregants, was a gross disproportion in numbers of cells belonging to the Ly1 and Ly123 sets, at the age of 3--3.5 mo. At this age, Ly123 cells of hr/hr spleen outnumbered Ly1 cells by 2:1, whereas in +/hr spleens Ly123 cells were outnumbered by approximately 1:2. Cells from pooled lymph nodes of hr/hr mice did not show a correspondingly gross disporprotion of Ly1 and Ly123 cells. Total counts of splenic T cells, and of B cells, were not significantly different in hr/hr and +/hr mice.

Clonal Analyses of Retroviral Vector Integrations in ADA-SCID Patients Treated with Stem Cell Gene Therapy.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3249-3249
Author(s):  
Barbara Cassani ◽  
Grazia Andolfi ◽  
Massimiliano Mirolo ◽  
Luca Biasco ◽  
Alessandra Recchia ◽  
...  
Keyword(s):  
Gene Therapy ◽  
T Cells ◽  
T Cell ◽  
Gene Transfer ◽  
Human Genome ◽  
Ex Vivo ◽  
Cd34 Cells

Abstract Gene transfer into hematopoietic stem/progenitor cells (HSC) by gammaretroviral vectors is an effective treatment for patients affected by severe combined immunodeficiency (SCID) due to adenosine deaminase (ADA)-deficiency. Recent studied have indicated that gammaretroviral vectors integrate in a non-random fashion in their host genome, but there is still limited information on the distribution of retroviral insertion sites (RIS) in human long-term reconstituting HSC following therapeutic gene transfer. We performed a genome-wide analysis of RIS in transduced bone marrow-derived CD34+ cells before transplantation (in vitro) and in hematopoietic cell subsets (ex vivo) from five ADA-SCID patients treated with gene therapy combined to low-dose busulfan. Vector-genome junctions were cloned by inverse or linker-mediated PCR, sequenced, mapped onto the human genome, and compared to a library of randomly cloned human genome fragments or to the expected distribution for the NCBI annotation. Both in vitro (n=212) and ex vivo (n=496) RIS showed a non-random distribution, with strong preference for a 5-kb window around transcription start sites (23.6% and 28.8%, respectively) and for gene-dense regions. Integrations occurring inside the transcribed portion of a RefSeq genes were more represented in vitro than ex vivo (50.9 vs 41.3%), while RIS <30kb upstream from the start site were more frequent in the ex vivo sample (25.6% vs 19.4%). Among recurrently hit loci (n=50), LMO2 was the most represented, with one integration cloned from pre-infusion CD34+ cells and five from post-gene therapy samples (2 in granulocytes, 3 in T cells). Clone-specific Q-PCR showed no in vivo expansion of LMO2-carrying clones while LMO2 gene overexpression at the bulk level was excluded by RT-PCR. Gene expression profiling revealed a preference for integration into genes transcriptionally active in CD34+ cells at the time of transduction as well as genes expressed in T cells. Functional clustering analysis of genes hit by retroviral vectors in pre- and post-transplant cells showed no in vivo skewing towards genes controlling self-renewal or survival of HSC (i.e. cell cycle, transcription, signal transduction). Clonal analysis of long-term repopulating cells (>=6 months) revealed a high number of distinct RIS (range 42–121) in the T-cell compartment, in agreement with the complexity of the T-cell repertoire, while fewer RIS were retrieved from granulocytes. The presence of shared integrants among multiple lineages confirmed that the gene transfer protocol was adequate to allow stable engraftment of multipotent HSC. Taken together, our data show that transplantation of ADA-transduced HSC does not result in skewing or expansion of malignant clones in vivo, despite the occurrence of insertions near potentially oncogenic genomic sites. These results, combined to the relatively long-term follow-up of patients, indicate that retroviral-mediated gene transfer for ADA-SCID has a favorable safety profile.

A Human Hematopoietic Environment and Autologous T-Cell Growth Support Proliferation of Chronic Lymphocytic Leukemia B Cells in Immune-Deficient Mice

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 26-26
Author(s):  
Davide Bagnara ◽  
Matthew Kaufman ◽  
Xiao J. Yan ◽  
Kanti Rai ◽  
Nicholas Chiorazzi
Keyword(s):  
Cell Division ◽  
T Cell ◽  
B Cells ◽  
Cell Growth ◽  
Lymphocytic Leukemia ◽  
Leukemic Cells ◽  
Hematopoietic Microenvironment ◽  
Cd34 Cells ◽  
T Cell Growth

Abstract B-cell type chronic lymphocytic leukemia (B-CLL), an incurable disease of unknown etiology, results from the clonal expansion of a CD5+CD19+ B lymphocyte. Progress into defining the cell of origin of the disease and identifying a stem cell reservoir has been impeded because of the lack of reproducible models for growing B-CLL cells in vitro and in vivo. To date, attempts to adoptively transfer B-CLL cells into immune deficient mice and achieve engraftment and growth are sub-optimal. At least one possible cause for this is the murine microenvironment’s inability to support B-CLL survival and proliferation. We have attempted to overcome this barrier by creating a human hematopoietic microenvironment by reconstituting the tibiae of NOD/SCID/γcnull mice by intrabone (ib) injection of 1–3 × 105 CD34+ cord blood cells along with ~106 bone marrow-derived human mesenchymal stem cells (hMSCs). When human engraftment of 1–10% CD45+ cells was documented in the blood by immunofluorescence using flow cytometry, a total of 108 PBMCs from individual B-CLL patients were injected into the same bones. Before injection, B-CLL PBMCs were labeled with CFSE to permit distinction of leukemic B cells from normal B cells that might arise from the injected CD34+ cells. CFSE labeling also permitted tracking initial rounds of cell division in vivo. Every two weeks after B-CLL injection, peripheral blood from the mice was examined for the presence of cells bearing human CD45, CFSE, and various human lineage markers by flow cytometry. In the presence of a human hematopoietic microenvironment, CD5+CD19+ leukemic cells underwent at least 6 cell doublings, after which CFSE fluorescence was no longer detectable. Timing of B-CLL cell division varied among patients, occurring between 2 to 6 weeks after the injection of PBMC. In contrast, leukemic cells injected into mice that were not reconstituted by ib injection with hCD34+ cells and hMSCs or were reconstituted with only hMSCs failed to proliferate. Moreover the number of CFSE+CD5+CD19+ cells detected in the blood of mice with a human hematopoietic microenvironment far exceeded that in mice receiving only hMSC. Robust T-cell expansion occurred in several mice receiving CD34+ cells; in some instances T-cell growth was also found without hCD34+ cell injection, although in these cases it was usually less extensive. Based on genome-wide SNP analyses, the T cells were of B-CLL patient origin and not from hCD34+ cells. Furthermore, most of the mice with significant T-cell overexpansion died within 6 weeks of B-CLL cell injection from apparent graft vs. host disease. Therefore in subsequent experiments, we eliminated T cells by injecting an anti-CD3 antibody (OKT3); this treatment led to an inhibition of B-CLL cell proliferation. Moreover the percentage of CD38+ cells in the CFSE+CD5+CD19+ cell fraction was similar to that in the donor patient inoculum only in the mice in which T-cell-mediated B-CLL cell proliferation occurred. The percentage and intensity of CD38− expressing B-CLL cells was higher in the spleen and bone marrow (BM) of mice not treated with OKT3 antibody. Finally, the percentage of CFSE+CD5+CD19+ cells in the spleen far exceeded that in the blood, BM, liver and peritoneum, even when leukemic cells were no longer present in the blood and other organs; these findings suggest that the spleen is better at supporting B-CLL cell viability and proliferation than the other anatomic sites. These studies demonstrate conditions making adoptive xenogeneic transfer and clonal expansion of B-CLL cells into a mouse model possible. Factors conferring an advantage in this model include both a human hematopoietic environment and autologous T cell growth. Increased numbers of CD38+ B-CLL cells, similar to those in the patient, were only found when leukemic B cell division occurred. The optimal site for B-CLL cell growth was murine spleen. Since non-genetic factors promoting B-CLL expansion are not completely known, this model will be useful in discovering these as well as for studying the basic biology of this disease, such as if leukemic stem cells exist and also to conduct preclinical tests on possible therapeutics.

scholarly journals In vivo dual modality contemporaneous imaging of different tumor reactive T-cell subpopulations

2005 ◽  
Vol 11 (2) ◽  
pp. 57
Author(s):  
M.M. Doubrovin ◽  
E.S. Doubrovina ◽  
S. Cai ◽  
R.G. Blasberg ◽  
R.J. O’Reilly
Keyword(s):  
T Cell ◽  
Dual Modality ◽  
Cell Subpopulations ◽  
T Cell Subpopulations

Bexarotene-Induced T-Cell Immunomodulation and Response in CTCL.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 744-744 ◽  
Author(s):  
Pierluigi Porcu ◽  
Robert Baiocchi ◽  
Maureen Buckner ◽  
John C. Byrd ◽  
Cynthia M. Magro
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Count ◽  
Median Time ◽  
Median Duration ◽  
Cd8 T Cell ◽  
Cell Counts ◽  
Cell Subpopulations ◽  
T Cell Subpopulations

Abstract Cutaneous T-cell lymphoma (CTCL) is a group of chronic lymphoproliferative disorders mostly of skin-homing CD4+ T-cells associated with profound suppression of cell-mediated immunity and loss of T-cell reportoire. The immunological effects of current CTCL therapies and their impact on response have not been studied in large samples of patients. Bexarotene is a synthetic retinoic X receptor (RXR) agonist that induces apoptosis in malignant T-cells and has significant clinical activity in CTCL. Bexarotene also exerts multiple effects on normal T-cells. We investigated the in-vivo immunomodulatory effects of bexarotene in patients with CTCL and correlated them with response. 37 patients (pts) with stage IB-III CTCL (33 Mycosis Fungoides, 1 ALCL, 3 pleomorphic small cell) received oral bexarotene (150–300 mg/m2/day) for a median duration of 13 months (range 4–18). Peripheral blood (PB) T-cell subpopulations were measured by multicolor flow cytometry at baseline and during therapy. Circulating CTCL cells were defined as CD4+ CD7− T-cells. 32/37 patients had an elevated PB CD4/CD8 ratio at diagnosis, regardless of the presence of circulating CTCL cells (3/37 pts) and 33/37 pts had a low absolute CD8+ T-cell count (median 98 cells/mm3, normal 150–1000/mm3). After a median time of 6.5 weeks on bexarotene (range 3.5–12) the CD8+ T-cell count had returned within normal range in 26/33 pts and the CD4/CD8 ratio had decreased in 27/32 pts. Responses (defined as Pysician Global Assessment [PGA] of clinical condition) were observed in 24/37 pts (64.8%). Responders had significantly higher peak CD8+ T-cell counts compared to non-responders (median 975/mm3 vs 221/mm3, P=0.002) and lower CD4/CD8 ratios (median 0.8 vs 2.4, P=0.005). At this time 21 pts have relapsed, with median duration of response 9.5 months. A ≥50% decrease in the PB CD8+ T-cell count preceded cutaneous relapse in 17/21 pts (81%) by a median time of 4.5 weeks (range 3–6.5 weeks). Functional analysis (mitogenic response, cytokine secretion, antigenic repertoire) of PB T-cell subpopulations from these pts at baseline and during therapy with bexarotene is in progress. Bexarotene appears to have a profound in vivo T-cell immunomodulatory effect in CTCL pts. The importance of these immune effects for clinical response vis-a-vis direct induction of apoptosis in CTCL needs to be further studied. If these results are confirmed in larger samples, monitoring of PB T-cell subpopulations may provide clinically valuable information in predicting response and relapse.

Expression of CD10 and CD7 Defines Distinct In Vivo Lymphoid Reconstituting Capacity within Human Cord Blood CD34+CD38-Cells.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3184-3184
Author(s):  
Shuro Yoshida ◽  
Fumihiko Ishikawa ◽  
Leonard D. Shultz ◽  
Noriyuki Saito ◽  
Mitsuhiro Fukata ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
B Cells ◽  
Cord Blood ◽  
Nk Cells ◽  
Progenitor Cells ◽  
Human Cord Blood ◽  
Cd34 Cells

Abstract Human cord blood (CB) CD34+ cells are known to contain both long-term hematopoietic stem cells (LT-HSCs) and lineage-restricted progenitor cells. In the past, in vitro studies suggested that CD10, CD7 or CD127 (IL7Ra) could be candidate surface markers that could enrich lymphoid-restricted progenitor cells in human CB CD34+ cells (Galy A, 1995, Immunity; Hao QL, 2001, Blood; Haddad R, 2004, Blood). However, in vivo repopulating capacity of these lymphoid progenitors has not been identified due to the lack of optimal xenogeneic transplantation system supporting development of human T cells in mice. We aim to identify progenitor activity of human CB CD34+ cells expressing CD10/CD7 by using newborn NOD-scid/IL2rgKO transplant assay that can fully support the development of human B, T, and NK cells in vivo (Ishikawa F, 2005, Blood). Although LT-HSCs exist exclusively in Lin-CD34+CD38- cells, not in Lin-CD34+CD38+ cells, CD10 and CD7 expressing cells are present in Lin-CD34+CD38- cells as well as in Lin-CD34+CD38+ cells (CD10+CD7+ cells, CD10+CD7- cells, CD10-CD7+ cells, CD10-CD7- cells accounted for 4.7+/−2.7%, 10.5+/−1.9%, 7.6+/−4.4%, and 77.1+/−5.2% in Lin-CD34+CD38- CB cells, respectively). We transplanted 500–6000 purified cells from each fraction into newborn NOD-scid/IL2rgKO mice, and analyzed the differentiative capacity. CD34+CD38-CD10-CD7- cells engrafted long-term (4–6 months) in recipient mice efficiently (%hCD45+ cells in PB: 30–70%, n=5), and gave rise to all types of human lymphoid and myeloid progeny that included granulocytes, platelets, erythroid cells, B cells, T cells, and NK cells. Successful secondary reconstitution by human CD34+ cells recovered from primary recipient bone marrow suggested that self-renewing HSCs are highly enriched in CD34+CD38–CD10–CD7- cells. CD10–CD7+ cells were present more frequently in CD34+CD38+ cells rather than in CD34+CD38- cells. Transplantation of more than 5000 CD34+CD38+CD10–CD7+ cells, however, resulted in less than 0.5% human cell engraftment in the recipients. Within CD34+CD38–CD10+ cells, the expression of CD7 clearly distinguished the distinct progenitor capacity. At 8 weeks post-transplantation, more than 70% of total human CD45+ cells were T cells in the CD10+CD7+ recipients, whereas less than 30% of engrafted human CD45+ cells were T cells in the CD10+CD7– recipients. In the CD10+CD7- recipients, instead, more CD19+ B cells and HLA–DR+CD33+ cells were present in the peripheral blood, the bone marrow and the spleen. Both CD34+CD38–CD10+CD7+ and CD34+CD38–CD10+CD7- cells highly repopulate recipient thymus, suggesting that these progenitors are possible thymic immigrants. Taken together, human stem and progenitor activity can be distinguished by the expressions of CD7 and CD10 within Lin-CD34+CD38- human CB cells. Xenotransplant model using NOD-scid/IL2rgKO newborns enable us to clarify the heterogeneity of Lin-CD34+CD38- cells in CB by analyzing the in vivo lymphoid reconstitution capacity.

Probing the Impact of AMD3100/GCSF Mobilization on the Peripheral Blood T Cell Content Using a Rhesus Macaque Model: Increased Proportions of FoxP3+/CD4+ T Cells Occur After Mobilization and Leukapheresis

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 350-350
Author(s):  
Leslie Kean ◽  
Sharon Sen ◽  
Mark E Metzger ◽  
Aylin Bonifacino ◽  
Karnail Singh ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Peripheral Blood ◽  
Cd4 T Cells ◽  
Cell Populations ◽  
Macaque Model ◽  
Cd34 Cells ◽  
Cell Subpopulations ◽  
T Cell Subpopulations ◽  
The Impact

Abstract Abstract 350 Introduction: Leukapheresis is a widely utilized modality for collecting hematopoietic stem cells (HSCs). While collection of CD34+ cells with stem-cell activity is the primary goal of most mobilization and leukapheresis procedures, these cells only represent ∼1% of most leukapheresis products. The profile of the non-CD34+ cells is likely influenced by the choice of mobilization strategy, and has the potential to profoundly impact the post-transplant immune milieu of the transplant recipient. Two of the most critical of the CD34-negative cell populations that are collected during leukapheresis include effector and regulatory T cells. Thus, in evaluating mobilization regimens, the impact on these regimens on the mobilization of each of these T cell populations into the peripheral blood should be rigorously evaluated. Methods: We used a rhesus macaque model to determine the impact that mobilization with AMD3100 (a.k.a., Plerixafor or Mozobil®)+ G-CSF (“A+G”) had on peripheral blood CD4+ and CD8+ effector T cell populations as well as on FoxP3+/CD4+ T cells. Three rhesus macaques were mobilized with 10ug/kg SQ of G-CSF for five consecutive days prior to leukapheresis. AMD3100 was administered at 1mg/kg SQ in combination with the last dose of G-CSF two hours prior to leukapheresis. Leukapheresis procedures were performed for two hours using a modified CS3000 Plus cell separator. A peripheral blood sample was taken before cytokine therapy, just prior to leukapheresis following mobilization, one hour during leukapheresis, and at the end of the procedure. These samples were analyzed by multicolor flow cytometry using a BD LSRII flow cytometer. Results: Bulk, effector, and regulatory T cell subpopulations were analyzed flow cytometrically. The proportion of total CD3+ T cells remained stable during mobilization and apheresis: Thus, CD3+ T cells represented 77% of peripheral blood lymphocytes prior to mobilization, and 69% post-apheresis). The balance of CD4+ to CD8+ T cells was also relatively stable. Thus, for one of the three animals tested, the CD4+ and CD8+ proportions remained unchanged after apheresis. For two animals, the average CD4+ % decreased from 67% prior to mobilization to 52% post-apheresis. In these two animals, there was a reciprocal increase in the % of CD3+ T cells that were CD8+ (28% pre-G+A to 40% post-apheresis). The CD28+/CD95- naïve (Tn), CD28+/CD95+ central memory (Tcm) and CD28-/CD95+ effector memory (Tem) subpopulation balance of CD4+ and CD8+ T cells was also determined, by comparing the relative percentages of each subpopulation post-apheresis with their relative percentages prior to mobilization. Compared to their pre-G+A percentages, the post-apheresis CD4+ percentages of Tn, Tcm and Tem were 92%, 93% and 160%, respectively. Thus, the relative proportions of Tn and Tcm CD4+ cells decreased post-apheresis, while the relative proportion of CD4+ Tem increased compared to cytokine administration. For CD8+ T cell subpopulations, the post-apheresis proportions of Tn, Tcm, and Tem compared to their pre-G-CSF proportions were 99%, 70% and 130%, respectively–thus demonstrating the same direction of change as observed for CD4+ T cells. The most striking change in T cell subpopulations occurred in the CD4+/FoxP3+ compartment. The proportion of CD4+ T cells expressing FoxP3 increased by an average of 600% when post-apheresis samples were compared to pre-mobilization samples (FoxP3+ cells were 9.6% of CD4+ T cells post-apheresis versus 1.5% pre-GCSF). An average of 32% of these FoxP3+ CD4+ T cells expressed high levels of CXCR4. CXCR4 expression has been previously documented on human FoxP3+ T cells (Zou et al., Cancer Res, 2004), but this is the first observation of high level expression of CXCR4 on macaque FoxP3+ CD4 T cells, or of their ability to be efficiently mobilized with AMD3100. Discussion: These results suggest that treatment with AMD3100 and G-CSF may mobilize T cell subsets into the peripheral blood that could have beneficial effects during allo-transplantation. The combination of an increase in Tem cells, which have been observed to have decreased ability to cause GvHD (Zheng et al., Blood 2008), along with FoxP3+/CD4+ T cells, which may have regulatory functions, suggests that A+G mobilization could produce an apheresis product with a beneficial CD34-negative cell profile for allogeneic transplantation. Disclosures: No relevant conflicts of interest to declare.

Role of T cell subpopulations in mice infected with Angiostrongylus cantonensis

1996 ◽  
Vol 70 (3) ◽  
pp. 211-214 ◽  
Author(s):  
J.D. Lee ◽  
J.J. Wang ◽  
J.H. Chang ◽  
L.Y. Chung ◽  
E.R. Chen ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Immune Responses ◽  
Angiostrongylus Cantonensis ◽  
T Helper ◽  
The Third ◽  
Cell Subpopulations ◽  
T Cell Subpopulations

AbstractWhen C57BL/6 mice were infected with Angiostrongylus cantonensis, the percentage of T helper (CD4+) cells and T supressor (CD8+) cells in peripheral blood increased weekly until the third and seventh week respectively, and then gradually decreased. C57BL/6 mice were depleted of CD4+ and CD8+ T cells by in vivo injection of anti-CD4 and anti-CD8 monoclonal antibodies, respectively, and then infected with A. cantonensis. There were significantly more and less worms recovered in the mice depleted of CD4+ and CD8+ T cells respectively than in undepleted mice. Discrete subpopulations of T cells from mice exposed to A. cantonensis for 3 weeks or 7 weeks were adoptively transferred to syngeneic recipients which were then given a challenge infection. Protection was mediated by a CD4+ T cell population present in mice after 3 weeks of infection but was not demonstrable with cells taken 7 weeks after infection. When CD4+ T cells obtained from 3-week infected mice were mixed with 5% CD8+ T cells obtained from mice infected for 7 weeks, no significant transfer of resistance was observed. Thus, immune responses to A. cantonensis in mice were regulated by discrete subpopulations of T lymphocytes.

scholarly journals Production of a B cell growth-promoting activity, (DL)BCGF, from a cloned T cell line and its assay on the BCL1 B cell tumor.

1982 ◽  
Vol 156 (6) ◽  
pp. 1821-1834 ◽  
Author(s):  
S L Swain ◽  
R W Dutton
Keyword(s):  
T Cell ◽  
B Cells ◽  
Cell Growth ◽  
B Cell ◽  
Cell Line ◽  
Growth Promoting ◽  
Alloreactive T Cell ◽  
Culture Supernatants

Culture supernatants from a long-term alloreactive T cell line, the Dennert line C.C3.11.75 (DL) contain a B cell-growth-promoting activity. This activity can be assayed on normal B cells or on the in vivo BCL1 tumor line. We have called this activity (DL)BCGF. This activity can be distinguished from the T cell-replacing factor activity we had earlier found in DL supernates [(DL)TRF], which is required together with IL2 for the B cell plaque-forming cell response to erythrocyte antigens. The (DL)BCGF can be absorbed on untreated or glutaraldehyde-fixed BCL1. This absorption does not remove (DL)TRF activity. The production of (DL)BCGF is greatly enhanced when DL is cultured with IL2-containing supernatants. Sublines or clones of DL (DL.B10 and DL.A4) have been obtained that make large amounts of (DL)BCGF in the absence of any stimulator cells or IL2. B cells from the Xid-deficient male (DBA/2 X CBA/N)F1 mice do not respond to (DL)BCGF.

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