Human CD34+ Cells Express CXCR4 and Its Ligand Stromal Cell–Derived Factor-1. Implications for Infection by T-Cell Tropic Human Immunodeficiency Virus

Human CD34+ hematopoietic progenitor cells obtained from bone marrow (BM), umbilical cord blood (UCB), and mobilized peripheral blood (MPB) were purified and investigated for the expression of the chemokine receptor CXCR4 and its ligand, stromal cell–derived factor-1 (SDF-1). CXCR4 was found present on the cell surface of all CD34+ cells, although it was expressed at lower density on MPB with respect to BM CD34+ cells. Freshly isolated and in vitro–cultured CD34+ cells also coexpressed SDF-1 mRNA, as determined by reverse transcriptase-polymerase chain reaction (RT-PCR). Of interest, CD34+/CD38+ committed progenitor cells, unlike primitive CD34+/CD38− cells, expressed SDF-1 mRNA. Supernatants from in vitro–cultured CD34+ cells contained substantial (3 to 8 ng/mL) amounts of SDF-1 by enzyme-linked immunosorbent assay and induced migration of CD34+ cells. Because CD34+ cells express low levels of CD4, the primary receptor of the human immunodeficiency virus (HIV), and CXCR4 is a coreceptor for T-cell tropic (X4) HIV strains, we investigated the susceptibility of CD34+cells to infection by this subset of viruses. Lack of productive infection was almost invariably observed as determined by a conventional RT activity in culture supernatants and by real-time PCR for HIV DNA in CD34+ cells exposed to both laboratory adapted (LAI) and primary (BON) X4 T-cell tropic HIV-1 strain. Soluble gp120 Env (sgp120) from X4 HIV-1 efficiently blocked binding of the anti-CD4 Leu3a monoclonal antibody (MoAb) to either human CD4+ T cells or CD34+ cells. In contrast, sgp120 interfered with an anti-CXCR4 MoAb binding to human T lymphocytes, but not to CD34+ cells. However, CXCR4 on CD34+ cells was downregulated by SDF-1. These results suggest that CXCR4 and its ligand SDF-1 expressed in CD34+ progenitors may play an important role in regulating the local and systemic trafficking of these cells. Moreover, these findings suggest multiple and potentially synergistic mechanisms at the basis of the resistance of CD34+ cells to X4 HIV infection, including their ability to produce SDF-1, and the lack of CXCR4 internalization following gp120 binding to CD4.

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Exposure of human CD34+ cells to human immunodeficiency virus type 1 does not influence their expansion and proliferation of hematopoietic progenitors in vitro

Blood ◽

10.1182/blood.v88.1.130.130 ◽

1996 ◽

Vol 88 (1) ◽

pp. 130-137 ◽

Cited By ~ 21

Author(s):

S Kaushal ◽

VF La Russa ◽

S Gartner ◽

S Kessler ◽

S Perfetto ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Selection Process ◽

Pcr Analysis ◽

Liquid Cultures ◽

Human Cd34 ◽

Cd34 Cells ◽

Immunodeficiency Virus ◽

Hiv Exposed ◽

Hiv 1

Abstract The susceptibility of highly purified human CD34+ cells to monocytotropic (Ba-L) and lymphotropic (A018-post) strains of human immunodeficiency virus-1 (HIV-1) was examined. Liquid cultures initiated with fresh immunomagnetically purified CD34+ cells using the K6.1 CD34 monoclonal antibody (MoAb) (K6.1/CD34+) were positive for HIV expression 2 weeks after exposure to HIV-1 Ba-L. These cells were initially greater than 90% CD34+ and had undetectable monocyte contamination by flow-cytometric staining and side-scatter analyses, respectively, and undetectable T-cell contamination by CD3 polymerase chain reaction (PCR) analysis. However, secondary CD34+ liquid cultures reselected from the primary liquid cultures 24 hours after HIV exposure by panning with the ICH3 CD34 MoAb (ICH3/CD34+) and maintained for an additional 14 days were negative for HIV expression. The ICH3-unbound cells were positive for both spliced and unspliced HIV RNA when exposed to HIV-1 Ba-L, and were DNA PCR positive when exposed to either monocytotropic or lymphotropic HIV-1. To further test that CD34+ cells were not infectible by HIV-1, we exposed K6.1/CD34+ cells continuously to HIV-1 in a culture system capable of maintaining and expanding primitive CD34+ cells. HIV-exposed K6.1/CD34+ cells proliferated and expanded as efficiently as uninfected cultures. However, when reselected magnetically using the K6.1 CD34 MoAb after expansion for 7 days, bound K6.1/CD34+ cells were again negative for HIV-1 expression, whereas unbound cells were positive for HIV-1 expression. These findings suggest that a sequential CD34+ cell-selection process, in which the two selections are separated by a brief culture period, can yield a population of CD34+ cells that are not infected with HIV-1. This process may be useful in the design of stem or progenitor cell- based transplantation therapies for HIV infection.

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Expression of the Human Immunodeficiency Virus Type-1 Coreceptors CXCR-4 (fusin, LESTR) and CKR-5 in CD34+ Hematopoietic Progenitor Cells

Blood ◽

10.1182/blood.v89.10.3522 ◽

1997 ◽

Vol 89 (10) ◽

pp. 3522-3528 ◽

Cited By ~ 99

Author(s):

Martin Deichmann ◽

Ralf Kronenwett ◽

Rainer Haas

Keyword(s):

Human Immunodeficiency Virus ◽

T Cell ◽

Progenitor Cells ◽

Hematopoietic Progenitor Cells ◽

Cd4 Cells ◽

Hematopoietic Progenitor ◽

Cd34 Cells ◽

Immunodeficiency Virus ◽

Hiv 1

Abstract CD34+ hematopoietic progenitor cells were assessed for mRNA expression of the human immunodeficiency virus type-1 (HIV-1) coreceptors CXCR-4, also termed fusin or LESTR, and CKR-5, also called CC-CKR-5 or CCR-5. The CD34+ cells were obtained from leukapheresis products of 17 patients after granulocyte colony-stimulating factor–supported cytotoxic chemotherapy. Using a two-step enrichment procedure including immunomagnetic bead separation and fluorescence-activated cell sorting, the CD34+ cells had a median purity of 99.8%. Assessing 9 CD34+ cell samples by polymerase chain reaction after reverse transcription (RT-PCR), CXCR-4 mRNA was found in all samples, whereas CKR-5 mRNA was only present in 3 samples, even though a nested PCR was used. Eight additional CD34+ cell samples were sorted according to CD4 expression. Based on a three-color immunofluorescence analysis, the mean relative fluorescence intensity of HLA-DR was smaller on CD34+/CD4+ cells in comparison with CD34+/CD4− cells. CXCR-4 mRNA was found in 5 of 8 CD34+/CD4+ samples and in 7 of 8 CD34+/CD4− samples, whereas CKR-5 mRNA was detected in 2 CD34+/CD4+ samples and in 1 CD34+/CD4− cell sample. Looking at the total number of CD34+ cell samples examined, the proportion of specimens containing CXCR-4 mRNA was 84% in comparison with 24% of specimens positive for CKR-5 mRNA. These data suggest that CD34+/CD4+ hematopoietic progenitor cells, including true stem cell candidates, could be susceptible to HIV-1 infection. Considering the relatively low incidence of CD34+ cell samples containing CKR-5 mRNA, CD34+/CD4+ cells appear to be particularly prone for HIV-1 infection via the CXCR-4 coreceptor. Because this chemokine receptor allows T-cell–tropic HIV-1 strains to infect cells, CD34+ cells expressing CD4 and CXCR-4 might be infected by HIV-1 during later stages of the disease, following a viral phenotype switch from macrophage- to T-cell–tropic HIV-1 strains.

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Expression of the Human Immunodeficiency Virus Type-1 Coreceptors CXCR-4 (fusin, LESTR) and CKR-5 in CD34+ Hematopoietic Progenitor Cells

Blood ◽

10.1182/blood.v89.10.3522.3522_3522_3528 ◽

1997 ◽

Vol 89 (10) ◽

pp. 3522-3528 ◽

Cited By ~ 1

Author(s):

Martin Deichmann ◽

Ralf Kronenwett ◽

Rainer Haas

Keyword(s):

Human Immunodeficiency Virus ◽

T Cell ◽

Progenitor Cells ◽

Hematopoietic Progenitor Cells ◽

Cd4 Cells ◽

Hematopoietic Progenitor ◽

Cd34 Cells ◽

Immunodeficiency Virus ◽

Hiv 1

CD34+ hematopoietic progenitor cells were assessed for mRNA expression of the human immunodeficiency virus type-1 (HIV-1) coreceptors CXCR-4, also termed fusin or LESTR, and CKR-5, also called CC-CKR-5 or CCR-5. The CD34+ cells were obtained from leukapheresis products of 17 patients after granulocyte colony-stimulating factor–supported cytotoxic chemotherapy. Using a two-step enrichment procedure including immunomagnetic bead separation and fluorescence-activated cell sorting, the CD34+ cells had a median purity of 99.8%. Assessing 9 CD34+ cell samples by polymerase chain reaction after reverse transcription (RT-PCR), CXCR-4 mRNA was found in all samples, whereas CKR-5 mRNA was only present in 3 samples, even though a nested PCR was used. Eight additional CD34+ cell samples were sorted according to CD4 expression. Based on a three-color immunofluorescence analysis, the mean relative fluorescence intensity of HLA-DR was smaller on CD34+/CD4+ cells in comparison with CD34+/CD4− cells. CXCR-4 mRNA was found in 5 of 8 CD34+/CD4+ samples and in 7 of 8 CD34+/CD4− samples, whereas CKR-5 mRNA was detected in 2 CD34+/CD4+ samples and in 1 CD34+/CD4− cell sample. Looking at the total number of CD34+ cell samples examined, the proportion of specimens containing CXCR-4 mRNA was 84% in comparison with 24% of specimens positive for CKR-5 mRNA. These data suggest that CD34+/CD4+ hematopoietic progenitor cells, including true stem cell candidates, could be susceptible to HIV-1 infection. Considering the relatively low incidence of CD34+ cell samples containing CKR-5 mRNA, CD34+/CD4+ cells appear to be particularly prone for HIV-1 infection via the CXCR-4 coreceptor. Because this chemokine receptor allows T-cell–tropic HIV-1 strains to infect cells, CD34+ cells expressing CD4 and CXCR-4 might be infected by HIV-1 during later stages of the disease, following a viral phenotype switch from macrophage- to T-cell–tropic HIV-1 strains.

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Exposure of human CD34+ cells to human immunodeficiency virus type 1 does not influence their expansion and proliferation of hematopoietic progenitors in vitro

Blood ◽

10.1182/blood.v88.1.130.bloodjournal881130 ◽

1996 ◽

Vol 88 (1) ◽

pp. 130-137 ◽

Cited By ~ 2

Author(s):

S Kaushal ◽

VF La Russa ◽

S Gartner ◽

S Kessler ◽

S Perfetto ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Selection Process ◽

Pcr Analysis ◽

Liquid Cultures ◽

Human Cd34 ◽

Cd34 Cells ◽

Immunodeficiency Virus ◽

Hiv Exposed ◽

Hiv 1

The susceptibility of highly purified human CD34+ cells to monocytotropic (Ba-L) and lymphotropic (A018-post) strains of human immunodeficiency virus-1 (HIV-1) was examined. Liquid cultures initiated with fresh immunomagnetically purified CD34+ cells using the K6.1 CD34 monoclonal antibody (MoAb) (K6.1/CD34+) were positive for HIV expression 2 weeks after exposure to HIV-1 Ba-L. These cells were initially greater than 90% CD34+ and had undetectable monocyte contamination by flow-cytometric staining and side-scatter analyses, respectively, and undetectable T-cell contamination by CD3 polymerase chain reaction (PCR) analysis. However, secondary CD34+ liquid cultures reselected from the primary liquid cultures 24 hours after HIV exposure by panning with the ICH3 CD34 MoAb (ICH3/CD34+) and maintained for an additional 14 days were negative for HIV expression. The ICH3-unbound cells were positive for both spliced and unspliced HIV RNA when exposed to HIV-1 Ba-L, and were DNA PCR positive when exposed to either monocytotropic or lymphotropic HIV-1. To further test that CD34+ cells were not infectible by HIV-1, we exposed K6.1/CD34+ cells continuously to HIV-1 in a culture system capable of maintaining and expanding primitive CD34+ cells. HIV-exposed K6.1/CD34+ cells proliferated and expanded as efficiently as uninfected cultures. However, when reselected magnetically using the K6.1 CD34 MoAb after expansion for 7 days, bound K6.1/CD34+ cells were again negative for HIV-1 expression, whereas unbound cells were positive for HIV-1 expression. These findings suggest that a sequential CD34+ cell-selection process, in which the two selections are separated by a brief culture period, can yield a population of CD34+ cells that are not infected with HIV-1. This process may be useful in the design of stem or progenitor cell- based transplantation therapies for HIV infection.

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Ontogeny and Specificities of Mucosal and Blood Human Immunodeficiency Virus Type 1-Specific CD8+ Cytotoxic T Lymphocytes

Journal of Virology ◽

10.1128/jvi.77.1.291-300.2003 ◽

2003 ◽

Vol 77 (1) ◽

pp. 291-300 ◽

Cited By ~ 46

Author(s):

L. Musey ◽

Y. Ding ◽

J. Cao ◽

J. Lee ◽

C. Galloway ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

T Cell ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Cytotoxic T Lymphocyte ◽

Infected Individual ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Induction of adaptive immunity to human immunodeficiency virus type 1 (HIV-1) at the mucosal site of transmission is poorly understood but crucial in devising strategies to control and prevent infection. To gain further understanding of HIV-1-specific T-cell mucosal immunity, we established HIV-1-specific CD8+ cytotoxic T-lymphocyte (CTL) cell lines and clones from the blood, cervix, rectum, and semen of 12 HIV-1-infected individuals and compared their specificities, cytolytic function, and T-cell receptor (TCR) clonotypes. Blood and mucosal CD8+ CTL had common HIV-1 epitope specificities and major histocompatibility complex restriction patterns. Moreover, both systemic and mucosal CTL lysed targets with similar efficiency, primarily through the perforin-dependent pathway in in vitro studies. Sequence analysis of the TCRβ VDJ region revealed in some cases identical HIV-1-specific CTL clones in different compartments in the same HIV-1-infected individual. These results clearly establish that a subset of blood and mucosal HIV-1-specific CTL can have a common origin and can traffic between anatomically distinct compartments. Thus, these effectors can provide immune surveillance at the mucosa, where rapid responses are needed to contain HIV-1 infection.

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Impaired in vitro growth of purified (CD34+) hematopoietic progenitors in human immunodeficiency virus-1 seropositive thrombocytopenic individuals

Blood ◽

10.1182/blood.v79.10.2680.2680 ◽

1992 ◽

Vol 79 (10) ◽

pp. 2680-2687 ◽

Cited By ~ 8

Author(s):

G Zauli ◽

MC Re ◽

B Davis ◽

L Sen ◽

G Visani ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Liquid Culture ◽

Cell Number ◽

Hematopoietic Stem ◽

Cd34 Cells ◽

Immunodeficiency Virus ◽

P24 Antigen ◽

Hiv 1

Abstract In this report the role played by human immunodeficiency virus type-1 (HIV-1) in the pathogenesis of HIV-1-related thrombocytopenia was investigated. CD34+ hematopoietic stem/progenitor cells were purified from the bone marrow (BM) of HIV-1(+) thrombocytopenic patients, HIV- 1(+) nonthrombocytopenic individuals, HIV-1(-) patients with immune thrombocytopenic purpura, and HIV-1(-) normal donors. CD34+ cells from HIV-1(+) thrombocytopenic individuals alone showed a reduced capacity to give rise to megakaryocytic colonies (CFU-Meg) and also a progressive and significant decline in cell number when placed in liquid culture containing recombinant human interleukin-3 (rIL-3). This decline involved not only megakaryocyte but also erythroid and granulocyte/macrophage progenitors. The defects in megakaryocyte colony formation and CD34+ cell growth did not result from a productive HIV-1 infection of CD34+ cells. Moreover, HIV-1 DNA was absent from CD34+ cells in 10 of 12 thrombocytopenic patients examined. On the other hand, the decreased survival/proliferation of CD34+ cells in liquid culture, within the HIV-1(+) thrombocytopenic patients, was correlated with the presence of HIV-1 p24 antigen in BM plasma. These results demonstrate an impairment of CD34+ cells in HIV-1(+) individuals presenting thrombocytopenia as the only hematologic manifestation. Furthermore, these findings suggest that increased viral replication in the BM microenvironment may cause this impairment and possibly contributes to HIV-induced thrombocytopenia.

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Loss of primitive hematopoietic progenitors in patients with human immunodeficiency virus infection

Blood ◽

10.1182/blood.v88.12.4568.bloodjournal88124568 ◽

1996 ◽

Vol 88 (12) ◽

pp. 4568-4578 ◽

Cited By ~ 60

Author(s):

A Marandin ◽

A Katz ◽

E Oksenhendler ◽

M Tulliez ◽

F Picard ◽

...

Keyword(s):

Flow Cytometry ◽

Human Immunodeficiency Virus ◽

Long Term Culture ◽

Cd34 Cells ◽

Immunodeficiency Virus ◽

Cell Fractions ◽

Cd38 Antigen ◽

Hiv 1

A number of hematologic abnormalities, including cytopenias, have been observed in patients with human immunodeficiency virus (HIV) infection. To elucidate their mechanisms, primitive cells from bone marrow aspirates of 21 patients with HIV-1 infection were quantitated by flow cytometry. The mean percentage of CD34+ cells is not significantly altered in HIV-1-infected patients in comparison with HIV-1- seronegative controls. In contrast, two- and three-color immunofluorescence analysis showed that in all HIV-1 samples, most CD34+ cells coexpressed the CD38 antigen. The proportion of HIV-1- derived CD34+ cells that did not express the CD38 antigen was significantly lower (HIV-1+: mean, 1.73%; controls: mean, 14%; P < .0005) than in controls. Moreover, of Thy-1+ cells, the proportion of CD34+ cells was twofold lower in HIV-1-infected patients (HIV-1+: mean, 12%; controls, 25%, P < .0005), which suggests that phenotypically primitive cells are depleted in HIV-1 infection. In vitro functional analysis in long-term cultures of sorted CD34+ cells from seven HIV-1 patients showed that CD34+ cells from HIV-1 patients generated much fewer colonies both in the nonadherent and adherent layers than CD34+ cells from controls after 5 weeks of culture (10-fold and four-fold less, respectively). Precise long-term culture initiating cell (LTC-IC) frequency in the CD34+ cell population was determined in three patients by limiting dilution and was markedly decreased in comparison to that of normal controls (from twofold to > sevenfold decreased). To determine if primitive cells were infected by HIV-1, both methylcellulose colonies generated from long-term culture of CD34+ cells and various CD34+ cell fractions purified by flow cytometry were evaluated for the presence of HIV-1 by polymerase chain reaction (PCR). Progeny from long-term culture was HIV-1-negative in three samples. In addition, using a sensitive PCR technique, the HIV-1 genome could not be detected in CD34+, CD34+/CD38-, and CD34+/CD4+ cells. These data show that hematologic disorders in HIV disease may be the consequence of a deficit of primitive cells. However, direct infection of these cells by HIV-1 does not seem to be responsible for this defect.

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Inhibition of purified CD34+ hematopoietic progenitor cells by human immunodeficiency virus 1 or gp120 mediated by endogenous transforming growth factor beta 1.

Journal of Experimental Medicine ◽

10.1084/jem.183.1.99 ◽

1996 ◽

Vol 183 (1) ◽

pp. 99-108 ◽

Cited By ~ 56

Author(s):

G Zauli ◽

M Vitale ◽

D Gibellini ◽

S Capitani

Keyword(s):

Human Immunodeficiency Virus ◽

Growth Factor ◽

Progenitor Cells ◽

Transforming Growth Factor ◽

Hematopoietic Progenitor Cells ◽

Tgf Beta ◽

Hematopoietic Progenitor ◽

Cd34 Cells ◽

Immunodeficiency Virus ◽

Hiv 1

Human CD34+ hematopoietic progenitor cells, stringently purified from the peripheral blood of 20 normal donors, showed an impaired survival and clonogenic capacity after exposure to either heat-inactivated human immunodeficiency virus (HIV) 1 (strain IIIB) or cross-linked envelope gp120. Cell cycle analysis, performed at different times in serum-free liquid culture, showed an accumulation in G0/G1 in HIV-1- or gp120-treated cells and a progressive increase of cells with subdiploid DNA content, characteristic of apoptosis. In blocking experiments with anti-transforming growth factor (TGF) beta 1 neutralizing serum or TGF-beta 1 oligonucleotides, we demonstrated that the HIV-1- or gp120-mediated suppression of CD34+ cell growth was almost entirely due to an upregulation of endogenous TGF-beta 1 produced by purified hematopoietic progenitors. Moreover, by using a sensitive assay on the CCL64 cell line, increased levels of bioactive TGF-beta 1 were recovered in the culture supernatant of HIV-1/gp120-treated CD34+ cells. Anti-TGF-beta 1 neutralizing serum or TGF-beta 1 oligonucleotides were also effective in inducing a significant increase of the plating efficiency of CD34+ cells, purified from the peripheral blood of three HIV-1-seropositive individuals, suggesting that a similar mechanism may be also operative in vivo. The relevance of these findings to a better understanding of the pathogenesis of HIV-1-related cytopenias is discussed.

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Induction of Human Immunodeficiency Virus (HIV)-Specific CD8 T-Cell Responses by Listeria monocytogenes and a Hyperattenuated Listeria Strain Engineered To Express HIV Antigens

Journal of Virology ◽

10.1128/jvi.74.21.9987-9993.2000 ◽

2000 ◽

Vol 74 (21) ◽

pp. 9987-9993 ◽

Cited By ~ 41

Author(s):

Rachel S. Friedman ◽

Fred R. Frankel ◽

Zhan Xu ◽

Judy Lieberman

Keyword(s):

Human Immunodeficiency Virus ◽

Listeria Monocytogenes ◽

T Cell ◽

T Lymphocytes ◽

T Cell Immunity ◽

Vaccine Vector ◽

Cell Immunity ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Induction of cell-mediated immunity may be essential for an effective AIDS vaccine. Listeria monocytogenes is an attractive bacterial vector to elicit T-cell immunity to human immunodeficiency virus (HIV) because it specifically infects monocytes, key antigen-presenting cells, and because natural infection originates at the mucosa. Immunization with recombinant L. monocytogenes has been shown to protect mice from lymphocytic choriomeningitis virus, influenza virus, and tumor inoculation.L. monocytogenes expressing HIV gag elicits sustained high levels of Gag-specific cytotoxic T lymphocytes (CTLs) in mice. We have examined the ability of Listeria to infect human monocytes and present HIV antigens to CD8 T lymphocytes of HIV-infected donors to induce a secondary T-cell immune response. Using this in vitro vaccination protocol, we show that L. monocytogenes expressing the HIV-1 gag gene efficiently provides a strong stimulus for Gag-specific CTLs in HIV-infected donor peripheral blood mononuclear cells.Listeria expressing Nef also elicits a secondary in vitro anti-Nef CTL response. Since L. monocytogenes is a pathogen, before it can be seriously considered as a human vaccine vector, safety concerns must be addressed. We therefore have produced a highly attenuated strain of L. monocytogenes that requiresd-alanine for viability. The recombinant bacteria are attenuated at least 105-fold. We show that when these hyperattenuated bacteria are engineered to express HIV-1 Gag, they are at least as efficient at stimulating Gag-specific human CTLs in vitro as wild-type recombinants. These results suggest that attenuatedListeria is an attractive candidate vaccine vector to induce T-cell immunity to HIV in humans.

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