Immunoproteomic approach for identification of Ascaris suum proteins recognized by pigs with porcine ascariasis.

Ascaris suum, the causative agent of porcine ascariasis, is responsible for marked economic losses in pig farms worldwide. Despite recent advances in research, including the characterization of the genome of A. suum, knowledge about the parasite/host relationship in porcine ascariasis at the molecular level is scarce and chemotherapy is the only effective option for parasite control. The aim of this study was to identify immunogenic proteins of A. suum somatic antigens associated with the pathogenicity/survival mechanisms of the parasite, by using two-dimensional (2-D) electrophoresis, 2-D Western blot and mass spectrometry (MS). A total of 24 parasite proteins recognized by serum samples from pigs naturally infected with A. suum were identified. Most of them (23/24) were identified as being involved in parasite survival mechanisms, including functions related to energy generation (12 proteins) and redox processes (5 proteins). These results may aid the search for effective chemo-therapeutic targets in porcine ascariasis. Further studies are needed, however, to illustrate the effect of the host immune response on the survival mechanisms of A. suum.

Proteomic analysis of the urine of Dirofilaria immitis infected dogs.

Canine cardiopulmonary dirofilariosis caused by Dirofilaria immitis habitually develops as a chronic disease affecting pulmonary arteries, lung parenchyma and heart. Other organs like kidneys can also be involved. Renal pathology is a consequence of glomerulonephritis whose main sign is proteinuria. The aim of the present work is to identify proteins excreted in the urine of D. immitis infected dogs showing proteinuria, and the possible contribution of their loss to heartworm disease. Proteinuria is higher in microfilaremic (mf+) than in amicrofilaremic (mf-) dogs. Using bidimensional electrophoresis and mass spectrometry 9 different proteins from Canis lupus familiaris in the urine of both mf- and mf+ dogs were identified (serotransferrin isoform 6, serum albumin precursor, albumin, immunoglobulin gamma heavy chain D, apolipoprotein A-I, immunoglobulin lambda-like polypeptide 5-like, arginine esterase precursor, inmunoglobulin gamma heavy chain B and hemoglobin subunit alpha). Furthermore, 3 additional proteins were identified only in the urine of mf+ dogs, corresponding to dog fibrinogen alpha chain and immunoglobulin gamma heavy chain A and actin 2 homologous to a protein of Brugia malayi. The loss of these proteins and other in the urine of D. immitis infected dogs could affect the general condition of parasitized dogs through the interference in the cholesterol metabolism and O2 transport, among other mechanisms.