The Immunophenotype of Peritubular Capillaritis in Renal Transplant Biopsies.
1Centre for Complement and Inflammation Research, Imperial College, London, United Kingdom
2Cellular Pathology, King Saud University, Riyadh, Saudi Arabia
3Dept Renal Medicine, Imperial College Healthcare NHS Trust, London, United Kingdom
Meeting: 2017 American Transplant Congress
Abstract number: D36
Keywords: Biopsy, Inflammation, Rejection
Session Information
Session Name: Poster Session D: Diagnostics/Biomarkers Session II
Session Type: Poster Session
Date: Tuesday, May 2, 2017
Session Time: 6:00pm-7:00pm
Presentation Time: 6:00pm-7:00pm
Location: Hall D1
Background: Peritubular capillaritis (ptc) is a feature of acute antibody-mediated rejection (ABMR) in the renal allograft. However, it is not an specific feature for ABMR and can be seen in other causes of graft inflammation such as T-cell mediated rejection (TCMR), pyelonephritis (PN), and BK nephritis (BK). The immunophenotype of ptc has not been extensively investigated.
Methods: We conducted a pilot study of immunophenotyping of ptc in a group of 35 renal allograft biopsies: 11 ABMR/suspicious for ABMR (including C4d-negative cases), 13 TCMR/borderline for TCMR (BL), and 11 PN/BK nephropathy. We performed double labelling for a vascular markers (CD34) and for CD3, CD68, CD16 and CD14. Cells of each type were counted in 100consecutive peritubular capillaries in the most inflamed area and expressed as a mean number of cells/capillary. Results were compared between the 3 diagnostic categories by Kruskal-Wallis using GraphPad Prism software.
Results: The median and interquartile range for numbers of CD3, CD68, CD16 and CD14 in ptc for the 3 categories are shown here
| CD3 | CD14 | CD16 | CD68 | |
| PN/BK | 0.22 (0.07-0.35) | 0.08 (0.03-0.11) | 0.14 (0.05-0.27) | 0.085 (0.045-0.13) |
| TCMR | 0.14 (0.075-0.225) | 0.04 (0.02-0.07) | 0.08 (0.045-0.17) | 0.05 (0.02-0.13) |
| ABMR | 0.26 (0.12-0.44) | 0.11 (0.08-0.19) | 0.36 (0.14-0.70) | 0.16 (0.14-0.24) |
Using K-W analysis significant differences are seen in comparing CD14 (p=0.0368), CD16 (p=0.0325), and CD68 (p=0.0133). Multiple comparisons show there is a significance difference in TCMR vs ABMR for all 3 of these stains.
Conclusion: All diagnostic groups showed T-cells (CD3-positive) in peritubular capillaries, but ABMR showed significantly more abundant CD14+, CD16+, and CD68+ cells compared to TCMR. This did not reach significance between ABMR and PN/BK groups. Comparing monocyte markers, the number of CD68+ cell is consistently lower than that of CD16+ cell. CD68 may not be a good marker for intraluminal monocytes in ptc, in contrast to glomerulitis. However, the exact nature of the increased CD16-positive cells is not clear, as this marker can be expressed both in some subsets of monocytes and in NK cells.
CITATION INFORMATION: Chen T, Rasch L, Al Johani T, McPhail H, Willicombe M, McLean A, Galliford J, Cook T, Roufosse C. The Immunophenotype of Peritubular Capillaritis in Renal Transplant Biopsies. Am J Transplant. 2017;17 (suppl 3).
To cite this abstract in AMA style:
Chen T, Rasch L, Johani TAl, McPhail H, Willicombe M, McLean A, Galliford J, Cook T, Roufosse C. The Immunophenotype of Peritubular Capillaritis in Renal Transplant Biopsies. [abstract]. Am J Transplant. 2017; 17 (suppl 3). https://atcmeetingabstracts.com/abstract/the-immunophenotype-of-peritubular-capillaritis-in-renal-transplant-biopsies/. Accessed November 22, 2024.« Back to 2017 American Transplant Congress