Anti-A2M polyclonal antibody

We have investigated whether increased plasma protein leakage is present early after segmental allergen challenge in allergic asthma. Seven asthmatic subjects with mild allergy (AA group) and 5 non-asthmatic subjects with allergy (ANA group) were challenged with allergen doses based on similar early skin reactions; 5 healthy control subjects without allergy (C group) were challenged with the highest dose applied in the subjects with allergy, Bronchoalveolar ravage (BAL) fluid was obtained before, at 5 minutes after, and at 4 hours after challenge from different segments. Levels of albumin (Alb) and alpha(2)-macroglobulin (A2M) were measured in BAL fluid and serum. In addition, we calculated the relative coefficient of excretion as follows: RCE = ((A2M in BAL fluid)/(A2M in serum))/((Alb in BAL fluid)/(Alb in serum)). Also, levels of tryptase as a marker of mast cell activation and tumor necrosis factor-alpha (TNF-alpha), a possible inducer of plasma protein leakage, were determined. At 5 minutes after challenge, in none of the groups was a significant change found in the parameters for protein leakage. Levels of tryptase were increased in the subjects with allergy at 5 minutes after challenge only (P = .004), At 4 hours after challenge, levels of Alb (P = .03) and A2M (P = .04) and the RCE (P = .04) were increased in the AA group only. At 4 hours, levels of TNF-alpha were increased, with no significant differences among the three groups. In the asthmatic subjects with allergy, levels of TNF-alpha correlated with levels of Alb (r = 0.85, P = .02). In conclusion, at 4 hours after segmental allergen challenge, plasma protein leakage was increased in the asthmatic subjects only. The increase in levels of TNF-alpha in all groups indicates that the presence of TNF-alpha alone was not sufficient to cause plasma protein leakage within 4 hours after allergen challenge. Our results confirm the concept that plasma exudation after allergen exposure is a pathophysiologic event associated with asthma.

There is an urgent need for Alzheimer's disease (AD) biomarkers especially in the context of clinical trials. Biomarkers for early diagnosis, disease progression, and prediction are most critical, and disease-modification therapy development may depend on the discovery and validation of such markers. AddNeuroMed is a cross European, public/private consortium developed for AD biomarker discovery. We report here the development and design of AddNeuroMed and the progress toward the development of plasma markers. Despite the obstacles to such markers, we have identified a range of markers including CFH and A2M, both of which have been independently replicated. The experience of AddNeuroMed leads us to three overall conclusions. First, collaboration is essential. Second, design is paramount and combining modalities, such as imaging and proteomics, may be informative. Third, animal models are valuable in biomarker research. Most importantly, we have learned that plasma markers are feasible.