| First Author | Zheng Z | Year | 2018 |
| Journal | Arterioscler Thromb Vasc Biol | Volume | 38 |
| Issue | 11 | Pages | 2706-2717 |
| PubMed ID | 30354229 | Mgi Jnum | J:285161 |
| Mgi Id | MGI:6385475 | Doi | 10.1161/ATVBAHA.118.311728 |
| Citation | Zheng Z, et al. (2018) SR-BI (Scavenger Receptor Class B Type 1) Is Critical in Maintaining Normal T-Cell Development and Enhancing Thymic Regeneration. Arterioscler Thromb Vasc Biol 38(11):2706-2717 |
| abstractText | Objective- Continuous T-cell production from thymus is essential in replenishing naive T-cell pool and maintaining optimal T-cell functions. However, the underlying mechanisms regulating the T-cell development in thymus remains largely unknown. Approach and Results- We identified SR-BI (scavenger receptor class B type 1), an HDL (high-density lipoprotein) receptor, as a novel modulator in T-cell development. We found that SR-BI deficiency in mice led to reduced thymus size and decreased T-cell production, which was accompanied by narrowed peripheral naive T-cell pool. Further investigation revealed that SR-BI deficiency impaired progenitor thymic homing, causing a dramatic reduction in the percentage of earliest thymic progenitors, but did not affect other downstream T-cell developmental steps inside the thymus. As a result of the impaired progenitor thymic homing, SR-BI-deficient mice displayed delayed thymic regeneration postirradiation. Using a variety of experimental approaches, we revealed that the impaired T-cell development in SR-BI-deficient mice was not caused by hematopoietic SR-BI deficiency or SR-BI deficiency-induced hypercholesterolemia, but mainly attributed to the SR-BI deficiency in adrenal glands, as adrenal-specific SR-BI-deficient mice exhibited similar defects in T-cell development and thymic regeneration with SR-BI-deficient mice. Conclusions- This study demonstrates that SR-BI deficiency impaired T-cell development and delayed thymic regeneration by affecting progenitor thymic homing in mice, elucidating a previously unrecognized link between SR-BI and adaptive immunity. |
