Immaturity, immunological

Pieters RHH, Bol M, Ariens T, Punt P, Seinen W, Bloksma N, Penninks AH (1994c) Selective inhibition of immature CD4-CD8+ thymocyte proliferation, but not differentiation, by the thymus atrophy-inducing compound di-rvbutyltin dichloride. Immunology, 81(2) 261-267. 

The mechanism(s) underlying this protective default are only partially understood, but it appears that this immunological rheostat is set via the activity of local dendritic cell (DC) subsets [7]. Immature DC, such as those found within the respiratory... 

Enhancing the immune response in immunologically immature individuals... 

Examination of the separated cells, which were obtained in good yield (up to 80 percent), showed that they were fully viable (>95 percent in each fraction). In all the properties tested (surface markers, response to mitogens and immunological activities), the cells agglutinated by peanut agglutinin were essentially identical with the immunologically immature cells, whereas the nonagglutinated fraction consisted of... 

Immature T cells produced in the bone marrow ultimately migrate to the thymus, where they both expand and mature into immunologically competent cells (see Fig. 98 ). A variety of cytokines, including IL-2, IL-4, and lL-7, facilitate lymphopoiesis, whereas others such as transforming growth factor-/ may decelerate this process. T lymphocytes are probably the longest lived hematopoietic cell, as there is experimental evidence that the life span of some is more than 10 years. 

Splenic indices (spleen weight divided by body weight, mg/g) of immature, suckling pups treated with heterogeneic lymphocytes are commonly used in experimental immunology (Nikitin, 1982). In this experiment we compared the inbred and reciprocal hybrid litters, all of which were adjusted to 7 1 pups at birth. The pups were sacrificed and the spleen removed at 21 days postpartum. 

As for the experimental eczema of guinea pigs, there is neither a paranatal immunological immaturity nor a particular immunity in the new-born guinea pigs. 

There appears to be a spectrum of severity in the immimological defect in ADA deficiency which correlates closely with amounts of residual ADA activity in the lymphocytes. e suggest that erythrocyte dATP levels also provide an accurate guide to the immunodeficiency. It seems that those patients with the most severe forms (such as ours) with a complete deficiency of the enzyme, show the poorest response to therapy, and indeed may not respond at all. Another discrepancy exists between the degree to which we were able to correct the biochemical defects (deoxynucleotide levels decreased to less than 10 of pretreatment values) and the immunological improvement obtained. The precise mechanism by which the immunodeficiency is related to the lack of the purine enzyme remains imexplained. The observation in S.Y. that T cells remained immature despite full biochemical restoration emphasises the complexity of the immimodeficiency. It has been... 

Studies of Cooper, Asofsky, Lawton, and their eollaborators (89-91) as well as those of other investigators, have indicated that treatment of immunologically immature animals with anti-ju. chain antiserum can suppress the subsequent production of IgG and IgA, as well as IgM. The precise mechanisms involved remain to be elucidated, but the results are consistent with a switeh or transformation within a clone from the biosynthesis of one class of immunoglobulin to another class. 

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