Comparison of various methods for monitoring hybridoma cell proliferation.

The design of a strategy for the control of large scale cultures of hybridoma cells requires the use of convenient indicators to monitor properly the evolution of the biomass. In order to select appropriate indicators, we have measured in parallel, in bulk cultures of mouse hybridoma cells, the evolution of several metabolic parameters together with those of cell density and viability. We observed that flow cytometry analysis gives an early indication of the proliferative capacity of the cell population.

Gene for chronic proximal spinal muscular atrophies maps to chromosome 5q.

Proximal spinal muscular atrophies represent the second most common fatal, autosomal recessive disorder after cystic fibrosis. The childhood form is classically subdivided into three groups: acute Werdnig-Hoffmann (type I), intermediate Werdnig-Hoffmann disease (type II) and Kugelberg-Welander disease (type III). These different clinical forms have previously been attributed to either genetic heterogeneity or variable expression of different mutations at the same locus.

Heterogeneity of HLA genetic factors in IDDM susceptibility.

The association of certain HLA-D alleles with insulin-dependent diabetes mellitus (IDDM) is well known. One hundred and sixty-one non-related diabetic individuals and 142 non-related healthy controls were typed for the HLA DR-DQw-Dw association, using a restriction fragment length polymorphism (RFLP) typing method that combines three probe/enzyme systems: DRB/Taq I, DQB/Taq I, and DQB/Bam HI. Comparison of frequencies in both diabetics and controls confirms previous results in terms of HLA class II and IDDM association.

Combined immunodeficiency with abnormal expression of MHC class II genes.

The MHC class II CID represents an example of immunodeficiency in which the defect in expression of membrane glycoproteins leads to abnormal cell to cell interactions and thus to abnormal immune responses. It represents an interesting model which confirms the importance of MHC molecules in all immune responses to foreign antigens. It also underlines the complexity of regulatory mechanism which control the expression of MHC class II genes.

[Alpha genes of the T cell receptor: a possible implication in genetic susceptibility to multiple sclerosis].

Multiple sclerosis (MS) is a neurological disease in which 60% of patients are DR2 (versus 20% in controls). Restriction fragment length polymorphism (RFLP) associated with T cell receptor alpha-chain and beta-chain genes have been analysed in a sample of 46 MS patients and compared with those of 142 controls. The alpha-chain gene polymorphism is localized to the V-J region and consists of 3 Bgl II alleles (alpha a = 3.