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Activity and phenotype of natural killer cells in peptide transporter (TAP)-deficient patients (type I bare lymphocyte syndrome).

Zimmer J, Donato L, Hanau D, Cazenave JP, Tongio MM, Moretta A, de la Salle H - J. Exp. Med. (1998)

Bottom Line: Transporter associated to antigen processing (TAP)- NK cells proliferate when cultured in the presence of lymphoblastoid B cells (B-LCs) and interleukin 2 and develop a spectrum of cytotoxicity similar to that of activated normal NK cells.These receptors were expressed at normal levels, apart from the CD94-NKG2A complex, which appeared to be overexpressed.Finally, functional analyses indicated that the inhibitory receptors in TAP- individuals can transduce inhibitory signals.

View Article: PubMed Central - PubMed

Affiliation: Laboratoire d'Histocompatibilité, Contrat Jeune Formation Institut National de la Santé et de la Recherche Médicale 94-03, Strasbourg, France.

ABSTRACT
In this paper we describe the function and phenotype of natural killer (NK) lymphocytes from HLA class I-deficient patients. These cells are, as has been previously reported, unable to lyse HLA class I- K562 cells, but are able to perform antibody-dependent cellular cytotoxicity (ADCC), although with lower efficiency as compared to NK cells from normal individuals. Transporter associated to antigen processing (TAP)- NK cells proliferate when cultured in the presence of lymphoblastoid B cells (B-LCs) and interleukin 2 and develop a spectrum of cytotoxicity similar to that of activated normal NK cells. Importantly, activation of the TAP- NK cells induces strong cytotoxicity to autologous B-LCs. Analysis of the phenotype of circulating TAP- NK lymphocytes showed them to display a normal diverse repertoire of HLA class I-specific NK receptors. These receptors were expressed at normal levels, apart from the CD94-NKG2A complex, which appeared to be overexpressed. This latter finding could reflect an adaptation to the low expression of HLA class I molecules. Finally, functional analyses indicated that the inhibitory receptors in TAP- individuals can transduce inhibitory signals. Our results suggest that in vivo, the NK cells of TAP- patients could participate in immune defense, at least through ADCC, but upon activation, may be involved in autoimmune processes.

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(A) Repertoire of HLA class I–specific receptors on NK cells.  PBMCs from the TAP-deficient patients (filled squares and triangles), their  father (open squares), and 10 normal donors (open circles) were first incubated with anti-NK receptor mAbs, stained with a PE-conjugated goat  anti–mouse secondary antibody, and then labeled with FITC-conjugated  anti-CD3 and PE-Cy5–conjugated anti-CD19 mAbs. CD19− lymphocytes were analyzed by flow cytometry and results were expressed as the  percentage of positive cells among NK cells. (B) Comparison of the expression of NK receptors. The mean fluorescence intensities (MFI) of NK  cell subsets labeled with anti-NK receptor mAbs were determined by  flow cytometry for each donor. Mean values of MFI were calculated for  each marker and the ratio of the MFI to its corresponding mean value was  determined for each marker and individual. In the case of EB6, Z27, and  XA185, results were calculated for the bright subsets.
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Figure 3: (A) Repertoire of HLA class I–specific receptors on NK cells. PBMCs from the TAP-deficient patients (filled squares and triangles), their father (open squares), and 10 normal donors (open circles) were first incubated with anti-NK receptor mAbs, stained with a PE-conjugated goat anti–mouse secondary antibody, and then labeled with FITC-conjugated anti-CD3 and PE-Cy5–conjugated anti-CD19 mAbs. CD19− lymphocytes were analyzed by flow cytometry and results were expressed as the percentage of positive cells among NK cells. (B) Comparison of the expression of NK receptors. The mean fluorescence intensities (MFI) of NK cell subsets labeled with anti-NK receptor mAbs were determined by flow cytometry for each donor. Mean values of MFI were calculated for each marker and the ratio of the MFI to its corresponding mean value was determined for each marker and individual. In the case of EB6, Z27, and XA185, results were calculated for the bright subsets.

Mentions: To determine if the low expression of HLA class I molecules could affect the repertoire of HLA class I–specific NK receptors, the phenotype of TAP− NK cells was further analyzed by flow cytometry using different anti-NK receptor mAbs. PBMCs from the TAP-deficient patients, their father, and the same 10 normal donors (five Bw4-homozygous donors and five Bw6-homozygous donors) were stained with anti-CD3, anti-CD19, and anti-NK receptor mAbs for triple-color flow cytometry, CD19+ cells being excluded from the analysis. The percentages of NK cells (CD19−CD3−) and T lymphocytes (CD19−CD3+) expressing these different receptors were determined (Fig. 3 A, data not shown for T lymphocytes), as were the mean fluorescence intensities (MFI) of the receptors (Fig. 3 B). Experiments showed that the numbers of NK and T lymphocytes expressing these receptors varied among individuals, in agreement with previous reports (10–12). MFI of the different receptors also varied among donors, whereas no significant differences were observed between PBMCs from Bw4 and Bw6 homozygous normal individuals (data not shown). The two TAP-deficient patients expressed the KIRs recognized by the mAbs GL183, EB6, Z27, and Q66 on their NK and T cells. Thus, there was no apparent bias in the repertoire of these different HLA class I–specific KIRs, and no major differences in the MFI of the different receptors could be identified between TAP− and normal cells. Hence, our results suggest that the TAP deficiency does not affect the repertoire of Ig-SF KIRs. Some of these receptors were expressed at slightly different frequencies on the NK cells of the two HLA-identical patients. Analogous observations have been made by Gumperz et al. (10), who reported that the frequency of NK cells expressing the p70 receptor appeared to be controlled by genetic loci not linked to HLA.


Activity and phenotype of natural killer cells in peptide transporter (TAP)-deficient patients (type I bare lymphocyte syndrome).

Zimmer J, Donato L, Hanau D, Cazenave JP, Tongio MM, Moretta A, de la Salle H - J. Exp. Med. (1998)

(A) Repertoire of HLA class I–specific receptors on NK cells.  PBMCs from the TAP-deficient patients (filled squares and triangles), their  father (open squares), and 10 normal donors (open circles) were first incubated with anti-NK receptor mAbs, stained with a PE-conjugated goat  anti–mouse secondary antibody, and then labeled with FITC-conjugated  anti-CD3 and PE-Cy5–conjugated anti-CD19 mAbs. CD19− lymphocytes were analyzed by flow cytometry and results were expressed as the  percentage of positive cells among NK cells. (B) Comparison of the expression of NK receptors. The mean fluorescence intensities (MFI) of NK  cell subsets labeled with anti-NK receptor mAbs were determined by  flow cytometry for each donor. Mean values of MFI were calculated for  each marker and the ratio of the MFI to its corresponding mean value was  determined for each marker and individual. In the case of EB6, Z27, and  XA185, results were calculated for the bright subsets.
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Related In: Results  -  Collection

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Figure 3: (A) Repertoire of HLA class I–specific receptors on NK cells. PBMCs from the TAP-deficient patients (filled squares and triangles), their father (open squares), and 10 normal donors (open circles) were first incubated with anti-NK receptor mAbs, stained with a PE-conjugated goat anti–mouse secondary antibody, and then labeled with FITC-conjugated anti-CD3 and PE-Cy5–conjugated anti-CD19 mAbs. CD19− lymphocytes were analyzed by flow cytometry and results were expressed as the percentage of positive cells among NK cells. (B) Comparison of the expression of NK receptors. The mean fluorescence intensities (MFI) of NK cell subsets labeled with anti-NK receptor mAbs were determined by flow cytometry for each donor. Mean values of MFI were calculated for each marker and the ratio of the MFI to its corresponding mean value was determined for each marker and individual. In the case of EB6, Z27, and XA185, results were calculated for the bright subsets.
Mentions: To determine if the low expression of HLA class I molecules could affect the repertoire of HLA class I–specific NK receptors, the phenotype of TAP− NK cells was further analyzed by flow cytometry using different anti-NK receptor mAbs. PBMCs from the TAP-deficient patients, their father, and the same 10 normal donors (five Bw4-homozygous donors and five Bw6-homozygous donors) were stained with anti-CD3, anti-CD19, and anti-NK receptor mAbs for triple-color flow cytometry, CD19+ cells being excluded from the analysis. The percentages of NK cells (CD19−CD3−) and T lymphocytes (CD19−CD3+) expressing these different receptors were determined (Fig. 3 A, data not shown for T lymphocytes), as were the mean fluorescence intensities (MFI) of the receptors (Fig. 3 B). Experiments showed that the numbers of NK and T lymphocytes expressing these receptors varied among individuals, in agreement with previous reports (10–12). MFI of the different receptors also varied among donors, whereas no significant differences were observed between PBMCs from Bw4 and Bw6 homozygous normal individuals (data not shown). The two TAP-deficient patients expressed the KIRs recognized by the mAbs GL183, EB6, Z27, and Q66 on their NK and T cells. Thus, there was no apparent bias in the repertoire of these different HLA class I–specific KIRs, and no major differences in the MFI of the different receptors could be identified between TAP− and normal cells. Hence, our results suggest that the TAP deficiency does not affect the repertoire of Ig-SF KIRs. Some of these receptors were expressed at slightly different frequencies on the NK cells of the two HLA-identical patients. Analogous observations have been made by Gumperz et al. (10), who reported that the frequency of NK cells expressing the p70 receptor appeared to be controlled by genetic loci not linked to HLA.

Bottom Line: Transporter associated to antigen processing (TAP)- NK cells proliferate when cultured in the presence of lymphoblastoid B cells (B-LCs) and interleukin 2 and develop a spectrum of cytotoxicity similar to that of activated normal NK cells.These receptors were expressed at normal levels, apart from the CD94-NKG2A complex, which appeared to be overexpressed.Finally, functional analyses indicated that the inhibitory receptors in TAP- individuals can transduce inhibitory signals.

View Article: PubMed Central - PubMed

Affiliation: Laboratoire d'Histocompatibilité, Contrat Jeune Formation Institut National de la Santé et de la Recherche Médicale 94-03, Strasbourg, France.

ABSTRACT
In this paper we describe the function and phenotype of natural killer (NK) lymphocytes from HLA class I-deficient patients. These cells are, as has been previously reported, unable to lyse HLA class I- K562 cells, but are able to perform antibody-dependent cellular cytotoxicity (ADCC), although with lower efficiency as compared to NK cells from normal individuals. Transporter associated to antigen processing (TAP)- NK cells proliferate when cultured in the presence of lymphoblastoid B cells (B-LCs) and interleukin 2 and develop a spectrum of cytotoxicity similar to that of activated normal NK cells. Importantly, activation of the TAP- NK cells induces strong cytotoxicity to autologous B-LCs. Analysis of the phenotype of circulating TAP- NK lymphocytes showed them to display a normal diverse repertoire of HLA class I-specific NK receptors. These receptors were expressed at normal levels, apart from the CD94-NKG2A complex, which appeared to be overexpressed. This latter finding could reflect an adaptation to the low expression of HLA class I molecules. Finally, functional analyses indicated that the inhibitory receptors in TAP- individuals can transduce inhibitory signals. Our results suggest that in vivo, the NK cells of TAP- patients could participate in immune defense, at least through ADCC, but upon activation, may be involved in autoimmune processes.

Show MeSH
Related in: MedlinePlus