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ABSTRACTWe have recently cloned a new protein, recombinant P40 (rP40). When tested in vivo after conjugation to a B-cell epitope, rP40 induces an important antibody response without the need for adjuvant. To characterize its potency, this carrier protein was coupled to a peptide derived from respiratory syncytial virus attachment G protein (G1′). After immunization of mice with the rP40-G1′ conjugate, strong antipeptide antibodies were detected, whereas peptide alone was not immunogenic. To emphasize the carrier properties of rP40, a polysaccharide derived from Haemophilus influenzaetype b (Hib) was coupled to it. Immunoglobulin G responses against the Hib polysaccharide were observed after coupling to rP40. Interestingly, an antipeptide antibody response was observed despite preexisting anti-rP40 antibodies generated by preimmunization with rP40. In addition, rP40 compares well with the reference carrier protein, tetanus toxoid (TT), since antibody responses of equal intensity were observed when a peptide or a polysaccharide was coupled to TT and rP40. Moreover, rP40 had advantages compared to TT; e.g., it induced a mixed Th1/Th2 response, whereas TT induced only a Th2 profile. Together, the results indicate that rP40 is a novel carrier protein with potential for use as an alternative carrier for human vaccination.

Observations of acoustic images made along a transect perpendicular to the Coast, off Villefranche-sur-Mer, allow one to recognize the hydrological zone corresponding to a surface density gradient characterizing the Ligurian Sea front (Mediterranean Sea). Combinations of statistical and geometrical parameters from the digitized echoes enable discrimination between different classes of patches in relation to the frontal structure during one transect recorded on December 20, 1990. Patch recognition is based on the extraction of the general trend of each column and each row of the digitized data matrix by Eigenvector filtering. Multivariate analysis (principal component analysis and discriminant analysis) run on a 650 patches × 19 variables matrix shows a high negative relation between statistic and geometric parameters of the patches. The two main discriminant parameters are shape and echo strength of patches. From the convergence of our results in the Ligurian front with those of previous works made in other frontal region, it is suggested that this method could be generalized for quantifying and standardizing studies of the patchiness of plankton.

The Katholiek substrain of Brown Norway (BN/Kat) rats exhibits a very low level of circulating high-molecular-mass (HMW) kininogen and a partial deficiency in plasma prekallikrein. Northern blot analysis of liver RNA revealed that HMW kininogen and prekallikrein mRNAs are present in these rats with a similar size and abundance compared to control Brown Norway (BN/Orl) rats. The low-molecular-mass kininogen mRNA, encoded by the same kininogen gene as HMW kininogen MRNA by alternative splicing, is detected in both strains by dideoxynucleotide limited primer extension analysis. Measurement of HMW kininogen by radioimmunoassay was performed in liver subcellular fractions. It reveals that, in contrast to its absence in the cytosolic fraction, HMW kininogen in deficients rats is slightly more abundant in the microsomal fraction, than in control rats. These observations exclude both an abnormality at the level of gene transcription and a major structural modification of the transcribed RNA and of the synthesized HMW kininogen. They favour the hypothesis of an abnormal intracellular transport of the HMW kininogen in deficient rats.

The Katholiek substrain of Brown Norway (BN/Kat) rats exhibits a very low level of circulating high‐molecular‐mass (HMW) kininogen and a partial deficiency in plasma prekallikrein. Northern blot analysis of liver RNA revealed that HMW kininogen and prekallikrein mRNAs are present in these rats with a similar size and abundance compared to control Brown Norway (BN/Orl) rats. The low‐molecular‐mass kininogen mRNA, encoded by the same kininogen gene as HMW kininogen MRNA by alternative splicing, is detected in both strains by dideoxynucleotide limited primer extension analysis. Measurement of HMW kininogen by radioimmunoassay was performed in liver subcellular fractions. It reveals that, in contrast to its absence in the cytosolic fraction, HMW kininogen in deficients rats is slightly more abundant in the microsomal fraction, than in control rats. These observations exclude both an abnormality at the level of gene transcription and a major structural modification of the transcribed RNA and of the synthesized HMW kininogen. They favour the hypothesis of an abnormal intracellular transport of the HMW kininogen in deficient rats.