Extracellular trypanosomes can cause a wide range of diseases and pathological complications in a broad range of mammalian hosts. One common feature of trypanosomosis is the occurrence of anemia, caused by an imbalance between erythropoiesis and red blood cell clearance of aging erythrocytes. In murine models for T. brucei trypanosomosis, anemia is marked by a very sudden non-hemolytic loss of RBCs during the first-peak parasitemia control, followed by a short recovery phase and the subsequent gradual occurrence of an ever-increasing level of anemia. Using a newly developed quantitative pHrodo based in vitro erythrophagocytosis assay, combined with FACS-based ex vivo and in vivo results, we show that activated liver monocytic cells and neutrophils as well as activated splenic macrophages are the main cells involved in the occurrence of the early-stage acute anemia. In addition, we show that trypanosomosis itself leads to a rapid alteration of RBC membrane stability, priming the cells for accelerated phagocytosis.

The macroporous structure of poly(styrene-co-divinylbenzene) monolithic capillary columns has been optimized for the gradient separation of peptides. To exploit monolithic supports with porosity exceeding 70%, the thermodynamic properties of the polymerization mixture were carefully tailored to yield homogeneous monolithic materials featuring macropore and polymer microglobule sizes in the range of 50–200 nm. The effects of (i) initiator content, (ii) composition of porogenic mixture, comprising tetrahydrofuran and 1-decanol, (iii) percentage of divinylbenzene crosslinker, and (iv) monomers to porogen ratio on the morphology was investigated. The resulting column structures were investigated using scanning electron microscopy and the prepared monolithic columns were tested for the separation of a tryptic digest of cytochrome c while applying a fixed flow rate and gradient time. To obtain a better understanding of the effects of macropore and microglobule size, and structure homogeneity on the separation performance in gradient elution, both in terms of peak capacity and gradient plate height, separations were also carried out at different flow rates while maintaining a constant gradient steepness. Furthermore, performance limits were determined applying ultra-high pressure conditions up to the maximum system pressure of 80 MPa. The potential of monolithic nanostructured columns is demonstrated for the separation of tryptic digests of cytochrome c and bovine serum albumin.

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