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Updated: Jul 26, 2026
13:08
Expansion of Human Peripheral Blood γδ T Cells using Zoledronate
Published on: September 9, 2011
Signaling function of reconstituted CD16: zeta: gamma receptor complex isoforms
E Vivier1, N Rochet, M Ackerly
1Division of Tumor Immunology, Dana-Farber Cancer Institute, Boston, MA 02115.
International Immunology
|November 1, 1992
Summary
Natural killer cell activation relies on CD16 receptor signaling. The zeta and gamma chains differentially regulate this process, with gamma showing more efficient signal transduction than zeta in hematopoietic cells.
Area of Science:
- Immunology
- Cell Biology
- Molecular Signaling
Background:
- Natural killer (NK) cells utilize the Fc receptor for IgG (CD16) for activation.
- CD16 associates with disulfide-linked dimers of zeta or gamma chains for signal transduction.
- The distinct roles of zeta and gamma chains in CD16-mediated signaling are not fully understood.
Purpose of the Study:
- To compare the signal transduction capabilities of zeta and gamma chains associated with CD16.
- To investigate the molecular mechanisms underlying CD16-mediated activation in different cell types.
Main Methods:
- Constructed chimeric CD16 receptors with zeta or gamma cytoplasmic domains.
- Expressed these chimeric receptors in hematopoietic (Jurkat T cells) and non-hematopoietic (CHO cells) lines.
- Analyzed calcium influx, tyrosine phosphorylation, and IL-2 production as indicators of signal transduction.
Main Results:
- CD16/gamma chimeras showed more efficient signal transduction than CD16/zeta-zeta complexes in Jurkat cells.
- Both CD16/zeta and CD16/gamma chimeras were non-functional in CHO cells, indicating a requirement for hematopoietic-specific factors.
- The zeta transmembrane domain preferentially associated with CD16 over the CD3:TCR complex.
Conclusions:
- Zeta and gamma cytoplasmic domains couple to distinct tyrosine kinase pathways that differentially regulate CD16 activation.
- Hematopoietic cells possess essential downstream signaling components required for CD16 function.
- Molecular interactions involving the zeta transmembrane domain may influence NK and T cell differentiation hierarchies.
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