Phenomenological analysis of the dynamics of cryoaggregation by light-scattering spectrometry.

Cryoglobulins are proteins that precipitate at temperatures below 37 degreesC. Coldinduced precipitation of proteins may occur in vivo secondary to several important diseases, and lead to pathological manifestations involving different organs. Cryoprecipitation may be observed in vitro by exposing serum samples, supposed to contain cryoglobulins, to low temperatures, but this needs several days to occur. Proteinprotein interactions leading to cryoprecipitation are still poorly understood and the knowledge of the underlying mechanism may be relevant to the understanding of the onset of pathological manifestations. Using lightscattering spectrometry, we studied cryoprecipitation occurring in vitro at different temperatures and cryoglobulin concentrations. We describe the kinetics of the coldinduced precipitation of mixed cryoglobulins, measured as increase in turbidity. The plots obtained demonstrate that the cryoprecipitation did not occur as a singlestep reaction, but consisted of four distinct phases where both temperature and cryoglobulin concentration affected the immune complexes formation. Light scatter spectrometry may provide a simple, sensitive and rapid method for the detection of cryoglobulin

Sirolimus in association with mycophenolate mofetil induction for the prevention of acute graft rejection in renal allograft recipients

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Pathological crystallization of human immunoglobulins

Condensation of Igs has been observed in pharmaceutical formulations and in vivo in cases of cryoglobulinemia. We report a study of monoclonal IgG cryoglobulins overexpressed by two patients with multiple myeloma. These cryoglobulins form crystals, and we measured their solubility lines. Depending on the supersaturation, we observed a variety of condensate morphologies consistent with those reported in clinical investigations. Remarkably, the crystallization can occur at quite low concentrations. This suggests that, even within the regular immune response to infections, cryoprecipitation of Ig can be possible