Immunologic function and cell surface antigen expression of lymphocytes of dystrophic mice

Previous studies have reported abnormalities of thymic histology and cell numbers in 129/ ReJ-dy homozygous dystrophic mice, suggesting an association between murine muscular dystrophy and disorders of the immune system. The present study of C57BL/6J-dy^2J and 129/ReJ-dy homozygous dystrophic mice included a thorough analysis of thymic development and histology, of T-cell function demonstrated by mitogen stimulation, mixed-leukocyte culture, and graft-vs-host assays, and of surface antigen expression as measured by flow microfluorometry. Although sporadic differences can be seen in some dystrophic mice, we find no evidence of consistent abnormalities of the immune system in murine muscular dystrophy. It does not seem possible, therefore, to study either the dy or the dy^2J defect through analysis of lymphocytes. The feasibility of elucidating metabolic or membrane defects by utilizing cell populations other than those most conspicuously affected by a mutation with multisystem effects is discussed and our coincidental finding of a subpopulation of T cells with unusual antigenic properties is described.     

The relation between mitogen activated protein kinase (MAPK) pathway and different genes expression in patients with beta Thalassemia

Backgroundβ-thalassemia is an inherited hemoglobinopathy resulting in quantitative changes in the β-globin chain. Understanding the molecular basis of that disorder requires studying the expression of genes controlling the pathways that affect the erythropoietic homeostasis especially the MAPK pathway. The MAPKs are a family of serine/threonine kinases that play an essential role in connecting cell-surface receptors to DNA in the nucleus of the cell.Aimto study the effect of expression of GNAI2, DUSP5 and ARRB1 genes on MAPK signaling pathway in pediatric patients with beta thalassemia.MethodsForty children with beta thalassemia major (TM), forty children with beta thalassemia intermedia (TI) and forty age and gender matched healthy controls were enrolled in this study. Detection of GNAI2, DUSP5 and ARRB1 mRNA expression was done by real time polymerase chain reaction (RT-PCR).Resultsrevealed increased expression of ARRB1 (Arrestin Beta 1) gene, and decreased expression of both GNAI2 (Guanine nucleotide-binding protein G (i) subunit alpha-2) and DUSP5 (Dual specificity protein phosphatase 5) genes in both patient groups than control groups respectively.ConclusionsChange in the rate of expression of ARRB1, GNAI2 and DUSP5 may have a role in the pathogenesis of abnormal hematopoiesis in cases of β thalassemia through affecting the MAPK pathway.     

Antibody gene linkage studies in (NZB X C58) recombinant-inbred lines

A set of recombinant inbred mouse strains has been constructed from the cross of NZB by C58. These strains provide new tools for the analysis of antibody heavy and light chain genes and NZB autoimmunity. Typing of heavy chain genes confirmed the allotype linkage of the dextran response locus Igh-Dex. One strain has fixed a recombinant chromosome carrying NZB allotype genes and the Dex+ variable region gene from C58. Two kappa-light chain variable region genes, Igk-Pc and Igk-Ef1, co-segregated with the Lyt-2 lymphocyte alloantigen locus. This confirms the tight linkage of these loci and decreases the maximum estimate of the recombination frequency between them to 1.7%.     

SPORELING COALESCENCE IN CHONDRUS CRISPUS (RHODOPHYCEAE)1

Coalescence of developing sporelings of Chondrus crispus Stackhouse was observed. Juvenile tetra-sporophytes showed a higher proportion of coalescence than developing gametophytes. Stages of complete coalescence between different sporelings are illustrated. Coalesced sporelings exhibit vertical and horizontal alignment of cells, as well as “cuticular” continuity and secondary pit connections between adjacent, coalesced sporelings. Ultimately the cells in the center of the coalesced sporelings produce upright, multiaxial fronds that grow more rapidly than fronds of non-coalesced sporelings. Other red algae, such as Gracilaria verrucosa (Hudson) Papenfuss and Gigartina stellata (Stackhouse) Batters also show a similar sequence of sporeling coalescence and enhanced growth. The ecological significance of sporeling coalescence is discussed.