C-Terminal Alpha-1 Antitrypsin Peptide: A New Sepsis Biomarker with Immunomodulatory Function.

Systemic inflammatory response syndrome (SIRS) is a life threatening condition and the leading cause of death in intensive care units. Although single aspects of pathophysiology have been described in detail, numerous unknown mediators contribute to the progression of this complex disease. The aim of this study was to elucidate the pathophysiological role of CAAP48, a C-terminal alpha-1 antitrypsin fragment, that we found to be elevated in septic patients and to apply this peptide as diagnostic marker for infectious and noninfectious etiologies of SIRS. Incubation of human polymorphonuclear neutrophils with synthetic CAAP48, the SNP-variant CAAP47, and several control peptides revealed intense neutrophil activation, induction of neutrophil chemotaxis, reduction of neutrophil viability, and release of cytokines. We determined the abundance of CAAP48 in patients with severe sepsis, severe SIRS of noninfectious origin, and viral infection. CAAP48 levels were 3-4-fold higher in patients with sepsis compared to SIRS of noninfectious origin and allowed discrimination of those patients with high sensitivity and specificity. Our results suggest that CAAP48 is a promising discriminatory sepsis biomarker with immunomodulatory functions, particularly on human neutrophils, supporting its important role in the host response and pathophysiology of sepsis.

New aspects on chromosomal instability: chromosomal break-points in Fanconi anemia patients co-localize on the molecular level with fragile sites.

Within cytogenetic preparations chromosomal breaks can be observed in patients suffering from Fanconi anemia (FA), a recessively inherited syndrome with an extremely elevated cancer risk, but also in healthy individuals as so-called fragile sites (FS). It is known that FS cytogenetically co-localize with tumor- and evolutionary-conserved chromosomal break-points. The also suggested co-localization of FS and FA associated break-points (FA-bp) was studied here for the first time systematically by molecular cytogenetics. Metaphase chromosomes were obtained from lymphocytes of two FA patients (FANC-A and FANC-C, respectively). Overall 50.58% of the investigated FA-bp correspond to cytogenetic regions with known FS. A detailed molecular cytogenetic study applying FS-spanning probes revealed that 24/29 (82.8%) of analyzed FS are in concordance with FA-bp. Notably, FA-bp show a distribution pattern deviating from that of Aphidicolin induced FS. FA-bp appear more frequently within GTG-light bands and additionally, a yet unreported correlation was observed between break rate and chromosomal banding level. In future, FA-bp might serve as model for the mapping and analysis of otherwise rarely observable FS.

Global screening and extended nomenclature for 230 aphidicolin-inducible fragile sites, including 61 yet unreported ones.

Since the first description of human fragile sites (FS) more than 40 years ago, a variety of substances were reported to induce chromosomal breaks at non-random, breakage-prone regions. According to information available from human genome browsers aphidicolin, an inhibitor of DNA replication induces 77 of 88 known common FS. However, in the literature additional FS are reported, which are also, at least in part, inducible by aphidicolin. To the best of our knowledge, here we present the first and largest ever done systematic, whole genome-directed and comprehensive screening for aphidicolin-inducible breakage-prone regions. The study was performed on stimulated peripheral blood lymphocytes of 3 unrelated healthy individuals. Twenty-five thousand metaphase spreads were analyzed and overall 22,537 FS located in 230 different loci were recorded. Sixty-one of those FS were never observed before and 52 were already previously reported but not included in genome browsers and yet verified. Interestingly, aphidicolin was able to induce all types of rare and common FS, suggesting that these breakage-prone regions are less dependent on the inducing chemicals than originally supposed. Overall, we provide the first comprehensive genome wide map for FS and studied possible correlations of chromosome length and GTG-banding level with FS-frequency. To handle FS better in future, an extension of the already existing alphabetical nomenclature for FS on single chromosomes is suggested.