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J Rousseaux

Publications and source records attributed to J Rousseaux.

62 records · Page 4Linked to original sources
PubMedDate not supplied

Auto-antibodies to human sperm basic nuclear proteins in infertile and vasectomized men: characterization of antigens and epitopes recognized by antibodies.

The sera of vasectomized men and of patients with immune infertility were used to study the antigens and epitopes of sperm nuclear proteins that bind antibodies in these sera. No reaction with sperm histones was observed except for one serum. P1, P2 protamines and pro-P2 protamines were recognized by auto-antibodies. Studies with peptides derived from P1 and P2 protamines and with mammalian protamines related to HP1 showed that antibodies are mainly specific for a folded protamine molecule, more especially antibodies from vasectomized men. These results disagree with the random coil model proposed for protamines by several previous works. A cross-reactivity between P1 and P2 protamines was observed only for the whole molecules and not for peptides derived from them. This observation suggests that the two classes of protamines, different in sequence, may have a similar folding and thereby may be functionally equivalent.

Amino Acid Sequence↗
PubMedDate not supplied

Subclass restriction of the antiidiotypic antibody response in the rat.

Antiidiotypic antibodies were induced in LOU/M rats by immunization with two myeloma proteins of LOU origin: IR-162 (IgE) and IR-418 (IgG2a). Antibodies to IR-162 were easily obtained after a limited number of immunizations with protein in soluble form; polymerization with glutaraldehyde did not enhance immunogenicity. Antibodies to IR-418 appeared only after a large number of immunizations with protein in polymerized form or with protein copolymerized with rabbit IgG. All of the antibodies, either to IR-162 or to IR-418, were found to be idiotype-specific. In every case for which significant levels of antiidiotypic antibodies were produced, most or all of the antibodies belonged to rat IgG1 subclass. Since, in mice, antiidiotypic antibodies are restricted to the IgG1 subclass, our results indicate a functional analogy between rat and mouse IgG1. Our studies also suggest that the rat IgG1 subclass may be predominantly expressed in T-cell-dependent antibody responses, such as production of antiidiotypic antibodies.

Animals↗
PubMedDate not supplied

[Beta(o)/beta(o) thalassemia with a mild phenotype].

We report the case of a 30 years old patient of Algerian origin, presenting a beta-thalassemia major with a phenotype of intermediate severity. Its genotype is beta(o)/beta(o), leading to a complete absence of beta-globin synthesis. This genotype is usually responsible for major clinical complications and a severe anaemia requiring regular transfusions. However, the patient presents with a mild form of the disease and a moderate relatively well tolerated anaemia. This phenotype was found related to a high level of synthesis of foetal haemoglobin, dependent most probably on an homozygous state for the polymorphism (XmnI -158, C>T) in the promoter of the Ggamma gene. This observation shows that it is important to keep in mind that beta-thalassemia major may have a mild or intermediate phenotype because of polymorphisms of the beta locus.

Adult↗
PubMedDate not supplied

Genetic control of the resistance to spontaneous immunocytoma (plasmacytoma-IR tumour) development in LOU/C rats.

Immunocytomas (immunoglobulin secreting tumours) appear with a highly spontaneous incidence in animals of the inbred LOU/C strain but never in those of the inbred OKA strain. Congenic rats with LOU/C genetic background, having either the heavy or the kappa light immunoglobulin chain loci from the OKA strain, have an immunocytoma incidence similar to that of the LOU/C strain. The congenic strain, having the major histocompatibility complex of the OKA strain on the LOU/C background, showed no immunocytoma incidence. These results indicate that the MHC locus of the rat, or a gene closely linked to it, determines resistance to immunocytoma development. Specific chromosomal translocation associated with Ig gene chromosome and c-myc play a major role in the origin of the rat IR tumours. These experiments show that the resistance of the OKA strain to the appearance of IR tumours is not correlated with special properties of Ig heavy and kappa gene segments.

Animals↗
PubMedDate not supplied

[The HLA system: a clinical help?].

UNLABELLED: Chronic diseases are polymorph and influenced by many environmental and genetic factors. The HLA system is implicated in the modulation the onset and the evolution of chronic diseases. These observations are important to be considered for the prediction, prognosis and treatment adaptation. Evaluation tests are mainly statistical and are based on epidemiological studies. Thus, results must be considered with caution. Two aspects are to be considered: DIAGNOSIS: Associations between HLA alleles and chronic diseases are well known but concern very few diseases like narcolepsy or rheumatoid arthritis. Insulin dependent diabetes mellitus is particular because the prediction is limited to familial studies. PROGNOSIS: This point is less documented in clinical applications but is of interest particularly in inflammatory bowel diseases or systemic affections. This observation can be considered as a compartmental response which is a kind of adaptation to stress.

Alleles↗