gms | German Medical Science

102. Jahrestagung der DOG

Deutsche Ophthalmologische Gesellschaft e. V.

23. bis 26.09.2004, Berlin

Immune privilege parameters assayed in aqueous humor prior to and after penetrating keratoplasty to correlate with graft outcome

Meeting Abstract

  • corresponding author D. Böhringer - Augenklinik, Universitätsklinikum, Freiburg
  • J. S. Mo - Schepens Eye Research Institute, Boston, USA
  • D. Jung - Augenklinik, Heinrich-Heine-Universität, Düsseldorf
  • M. Kimmig - Augenklinik, Heinrich-Heine-Universität, Düsseldorf
  • H. Spelsberg - Augenklinik, Heinrich-Heine-Universität, Düsseldorf
  • R. Sundmacher - Augenklinik, Heinrich-Heine-Universität, Düsseldorf
  • W. Streilein - Schepens Eye Research Institute, Boston, USA
  • T. Reinhard - Augenklinik, Universitätsklinikum, Freiburg

Evidenzbasierte Medizin - Anspruch und Wirklichkeit. 102. Jahrestagung der Deutschen Ophthalmologischen Gesellschaft. Berlin, 23.-26.09.2004. Düsseldorf, Köln: German Medical Science; 2004. Doc04dogDO.16.12

The electronic version of this article is the complete one and can be found online at:

Published: September 22, 2004

© 2004 Böhringer et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.




Aqueous humor reflects the microenvironment of the anterior chamber, and displays attributes that correlate with the immune privileged nature of this site. We wished to determine whether immune privilege parameters assayed in aqueous humor are relevant to the fate of penetrating keratoplasty in humans.


Anterior chamber puncture was performed in 28 patients prior to PK (prospective cohort, 67% normal risk KP), in 6 of these patients with no history of graft rejection undergoing cataract surgery after PK (acceptors, 65% normal risk KP), in another 6 patients undergoing treatment of an acute endothelial immune reaction (rejectors, 33% normal risk KP), and in 65 controls undergoing uncomplicated cataract extraction. All aqueous humor (AqH) samples were tested for total protein concentration, ability to suppress in vitro T-cell activation, and total TGF-β2 content.


Mean total protein concentrations in AqH aspirates of acceptors and rejectors post-PK were elevated (2.7±0.8 and 2.7±0.7 mg/ml, respectively) compared to pre-PK AqH and cataract controls (1.0+0.1 mg/ml, p=0.01). All AqH samples suppressed T cell activation in vitro, irrespective of source and timing of AqH removal. Mean TGF-β content in AqH aspirates of pre-PK patients was significantly lower than that of cataract controls (2.9±0.7 vs. 17.1±3.2 ng/ml; p<0.05). AqH obtained from eyes of patients with accepted grafts displayed a trend toward higher mean TGF-β2 content than AqH from eyes with rejected grafts (5.4±1.5 ng/ml vs. 2.0±0.4; p=0.06). Higher mean total TGF-β2 levels tended to correlate with higher loss of corneal endothelial cells in the absence of clinical evidence of immune inflammation (R2=0.6; p=0.08).


Assays of immune privilege markers in AqH reveal that mean TGF-β2 content is abnormally low in patients coming to PK due to the high risk cases and that PK surgery results in a sustained loss of integrity of the blood-aqueous barrier. Although trends were evident, values of immune privilege markers determined pre- and post-PK failed to predict graft fate or extent of endothelial cell loss with statistical significance. Identification of further parameters predicting graft outcome is subject to forthcoming investigations.