Limits...
Low frequency of CD4+CD25+ Treg in SLE patients: a heritable trait associated with CTLA4 and TGFbeta gene variants.

Barreto M, Ferreira RC, Lourenço L, Moraes-Fontes MF, Santos E, Alves M, Carvalho C, Martins B, Andreia R, Viana JF, Vasconcelos C, Mota-Vieira L, Ferreira C, Demengeot J, Vicente AM - BMC Immunol. (2009)

Bottom Line: We further ascertained that the decreased frequency of Treg in SLE patients resulted from the specific reduction of bona fide FOXP3+CD4+CD25+ Treg.Candidate gene analysis revealed that specific variants of CTLA4 and TGFbeta were associated with the decreased frequency of Treg in PBMC, while FOXP3 gene variants were associated with affection status, but not with Treg frequency.SLE patients have impaired Treg production or maintenance, a trait strongly associated with SLE disease activity and autoantibody titers, and possibly resulting from the inability to convert FOXP3+CD25- into FOXP3+CD25+ T cells.

View Article: PubMed Central - HTML - PubMed

Affiliation: Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6 2780-156 Oeiras, Portugal. mbarreto@igc.gulbenkian.pt

ABSTRACT

Background: CD4+CD25+ regulatory T cells play an essential role in maintaining immune homeostasis and preventing autoimmunity. Therefore, defects in Treg development, maintenance or function have been associated with several human autoimmune diseases including Systemic Lupus Erythematosus (SLE), a systemic autoimmune disease characterized by loss of tolerance to nuclear components and significantly more frequent in females.

Results: To investigate the involvement of Treg in SLE pathogenesis, we determined the frequency of CD4+CD25+CD45RO+ T cells, which encompass the majority of Treg activity, in the PBMC of 148 SLE patients (76 patients were part of 54 families), 166 relatives and 117 controls. SLE patients and their relatives were recruited in several Portuguese hospitals and through the Portuguese Lupus Association. Control individuals were blood donors recruited from several regional blood donor centers. Treg frequency was significantly lower in SLE patients than healthy controls (z = -6.161, P < 0.00001) and intermediate in the relatives' group. Remarkably, this T cell subset was also lower in females, most strikingly in the control population (z = 4.121, P < 0.001). We further ascertained that the decreased frequency of Treg in SLE patients resulted from the specific reduction of bona fide FOXP3+CD4+CD25+ Treg. Treg frequency was negatively correlated with SLE activity index (SLEDAI) and titers of serum anti-dsDNA antibodies. Both Treg frequency and disease activity were modulated by IVIg treatment in a documented SLE case. The segregation of Treg frequency within the SLE families was indicative of a genetic trait. Candidate gene analysis revealed that specific variants of CTLA4 and TGFbeta were associated with the decreased frequency of Treg in PBMC, while FOXP3 gene variants were associated with affection status, but not with Treg frequency.

Conclusion: SLE patients have impaired Treg production or maintenance, a trait strongly associated with SLE disease activity and autoantibody titers, and possibly resulting from the inability to convert FOXP3+CD25- into FOXP3+CD25+ T cells. Treg frequency is highly heritable within SLE families, with specific variants of the CTLA4 and TGFbeta genes contributing to this trait, while FOXP3 contributes to SLE through mechanisms not involving a modulation of Treg frequency. These findings establish that the genetic components in SLE pathogenesis include genes related to Treg generation or maintenance.

Show MeSH

Related in: MedlinePlus

CD4+CD25+CD45RO+ T cell frequency of an SLE patient before (A) and after (B) SLE diagnosis. (C) CD4+CD25+CD45RO+ T cell frequency of an SLE patient at the time of flare, (D) upon corticosteroid and anticoagulant therapy and (E) after IVIg administration. Lymphocytes gated according to forward and side scatter (FSC/SSC) from PBMC were screened by flow cytometry for the presence of CD4+CD25+CD45RO+ T cells. The FACS panel representing CD4+CD25+CD45RO+ is gated on CD4+ cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2656467&req=5

Figure 5: CD4+CD25+CD45RO+ T cell frequency of an SLE patient before (A) and after (B) SLE diagnosis. (C) CD4+CD25+CD45RO+ T cell frequency of an SLE patient at the time of flare, (D) upon corticosteroid and anticoagulant therapy and (E) after IVIg administration. Lymphocytes gated according to forward and side scatter (FSC/SSC) from PBMC were screened by flow cytometry for the presence of CD4+CD25+CD45RO+ T cells. The FACS panel representing CD4+CD25+CD45RO+ is gated on CD4+ cells.

Mentions: In two SLE patients variations in CD4+CD25+CD45RO+ T cell frequency as a function of disease onset and progression and with treatment were evaluated. A 33-year-old Caucasian woman was initially enrolled in this study as a healthy relative of an SLE patient. At the time of recruitment, the frequency of CD4+CD25+CD45RO+ T cells in this subject was 4.60% (Figure 5A). One year later, this woman presented classical SLE clinical symptoms, lymphopenia, positive anti-dsDNA antibody, positive lupic anticoagulant and a SLEDAI of 10. Upon establishment of the diagnosis of SLE, a new measurement of Treg frequency showed a decrease to 2.88% (Figure 5B), suggesting the involvement of CD4+CD25+CD45RO+ T cell frequency in the onset of symptoms. In a second case a 67-year-old female SLE patient, diagnosed three years before, developed an SLE flare with symptoms of acute isquemic stroke, hemolytic anemia, impaired renal function, antinuclear, anti-dsDNA and anticardiolipin antibodies and hipocomplementemia. The SLEDAI score was 42. A regimen of low-dose corticosteroids and antimalarials had previously provided a good control of disease. At this point the CD4+CD25+CD45RO+ T cell frequency was 4.22% (Figure 5C). After anticoagulant and intravenous corticosteroid therapies, the CD4+CD25+CD45RO+ T cell frequency was 4.30% (Figure 5D). In addition to anticoagulants and intravenous corticosteroids therapies, IVIg therapy administration was deemed necessary. Upon IVIg treatment, the patient's CD4+CD25+CD45RO+ T cell frequency increased to 7.12% (Figure 5E) and she showed progressive clinical and laboratorial improvement, and the SLEDAI score decreased to 12 after three weeks of treatment. Taken together these results support the idea that decreased CD25+ T cell frequency is associated with disease activity.


Low frequency of CD4+CD25+ Treg in SLE patients: a heritable trait associated with CTLA4 and TGFbeta gene variants.

Barreto M, Ferreira RC, Lourenço L, Moraes-Fontes MF, Santos E, Alves M, Carvalho C, Martins B, Andreia R, Viana JF, Vasconcelos C, Mota-Vieira L, Ferreira C, Demengeot J, Vicente AM - BMC Immunol. (2009)

CD4+CD25+CD45RO+ T cell frequency of an SLE patient before (A) and after (B) SLE diagnosis. (C) CD4+CD25+CD45RO+ T cell frequency of an SLE patient at the time of flare, (D) upon corticosteroid and anticoagulant therapy and (E) after IVIg administration. Lymphocytes gated according to forward and side scatter (FSC/SSC) from PBMC were screened by flow cytometry for the presence of CD4+CD25+CD45RO+ T cells. The FACS panel representing CD4+CD25+CD45RO+ is gated on CD4+ cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2656467&req=5

Figure 5: CD4+CD25+CD45RO+ T cell frequency of an SLE patient before (A) and after (B) SLE diagnosis. (C) CD4+CD25+CD45RO+ T cell frequency of an SLE patient at the time of flare, (D) upon corticosteroid and anticoagulant therapy and (E) after IVIg administration. Lymphocytes gated according to forward and side scatter (FSC/SSC) from PBMC were screened by flow cytometry for the presence of CD4+CD25+CD45RO+ T cells. The FACS panel representing CD4+CD25+CD45RO+ is gated on CD4+ cells.
Mentions: In two SLE patients variations in CD4+CD25+CD45RO+ T cell frequency as a function of disease onset and progression and with treatment were evaluated. A 33-year-old Caucasian woman was initially enrolled in this study as a healthy relative of an SLE patient. At the time of recruitment, the frequency of CD4+CD25+CD45RO+ T cells in this subject was 4.60% (Figure 5A). One year later, this woman presented classical SLE clinical symptoms, lymphopenia, positive anti-dsDNA antibody, positive lupic anticoagulant and a SLEDAI of 10. Upon establishment of the diagnosis of SLE, a new measurement of Treg frequency showed a decrease to 2.88% (Figure 5B), suggesting the involvement of CD4+CD25+CD45RO+ T cell frequency in the onset of symptoms. In a second case a 67-year-old female SLE patient, diagnosed three years before, developed an SLE flare with symptoms of acute isquemic stroke, hemolytic anemia, impaired renal function, antinuclear, anti-dsDNA and anticardiolipin antibodies and hipocomplementemia. The SLEDAI score was 42. A regimen of low-dose corticosteroids and antimalarials had previously provided a good control of disease. At this point the CD4+CD25+CD45RO+ T cell frequency was 4.22% (Figure 5C). After anticoagulant and intravenous corticosteroid therapies, the CD4+CD25+CD45RO+ T cell frequency was 4.30% (Figure 5D). In addition to anticoagulants and intravenous corticosteroids therapies, IVIg therapy administration was deemed necessary. Upon IVIg treatment, the patient's CD4+CD25+CD45RO+ T cell frequency increased to 7.12% (Figure 5E) and she showed progressive clinical and laboratorial improvement, and the SLEDAI score decreased to 12 after three weeks of treatment. Taken together these results support the idea that decreased CD25+ T cell frequency is associated with disease activity.

Bottom Line: We further ascertained that the decreased frequency of Treg in SLE patients resulted from the specific reduction of bona fide FOXP3+CD4+CD25+ Treg.Candidate gene analysis revealed that specific variants of CTLA4 and TGFbeta were associated with the decreased frequency of Treg in PBMC, while FOXP3 gene variants were associated with affection status, but not with Treg frequency.SLE patients have impaired Treg production or maintenance, a trait strongly associated with SLE disease activity and autoantibody titers, and possibly resulting from the inability to convert FOXP3+CD25- into FOXP3+CD25+ T cells.

View Article: PubMed Central - HTML - PubMed

Affiliation: Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6 2780-156 Oeiras, Portugal. mbarreto@igc.gulbenkian.pt

ABSTRACT

Background: CD4+CD25+ regulatory T cells play an essential role in maintaining immune homeostasis and preventing autoimmunity. Therefore, defects in Treg development, maintenance or function have been associated with several human autoimmune diseases including Systemic Lupus Erythematosus (SLE), a systemic autoimmune disease characterized by loss of tolerance to nuclear components and significantly more frequent in females.

Results: To investigate the involvement of Treg in SLE pathogenesis, we determined the frequency of CD4+CD25+CD45RO+ T cells, which encompass the majority of Treg activity, in the PBMC of 148 SLE patients (76 patients were part of 54 families), 166 relatives and 117 controls. SLE patients and their relatives were recruited in several Portuguese hospitals and through the Portuguese Lupus Association. Control individuals were blood donors recruited from several regional blood donor centers. Treg frequency was significantly lower in SLE patients than healthy controls (z = -6.161, P < 0.00001) and intermediate in the relatives' group. Remarkably, this T cell subset was also lower in females, most strikingly in the control population (z = 4.121, P < 0.001). We further ascertained that the decreased frequency of Treg in SLE patients resulted from the specific reduction of bona fide FOXP3+CD4+CD25+ Treg. Treg frequency was negatively correlated with SLE activity index (SLEDAI) and titers of serum anti-dsDNA antibodies. Both Treg frequency and disease activity were modulated by IVIg treatment in a documented SLE case. The segregation of Treg frequency within the SLE families was indicative of a genetic trait. Candidate gene analysis revealed that specific variants of CTLA4 and TGFbeta were associated with the decreased frequency of Treg in PBMC, while FOXP3 gene variants were associated with affection status, but not with Treg frequency.

Conclusion: SLE patients have impaired Treg production or maintenance, a trait strongly associated with SLE disease activity and autoantibody titers, and possibly resulting from the inability to convert FOXP3+CD25- into FOXP3+CD25+ T cells. Treg frequency is highly heritable within SLE families, with specific variants of the CTLA4 and TGFbeta genes contributing to this trait, while FOXP3 contributes to SLE through mechanisms not involving a modulation of Treg frequency. These findings establish that the genetic components in SLE pathogenesis include genes related to Treg generation or maintenance.

Show MeSH
Related in: MedlinePlus