Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Institutionalized patients with Down syndrome and matched controls with other causes of mental retardation were tested by immune adherence hemagglutination for the presence of antibody to hepatitis A antigen (anti-HA). Altogether 75.1% (175 of 233) exhibited presence of anti-HA, with no differences by sex or age. Patients reactive for hepatitis B surface antigen (HBsAg) or its antibody (anti-HBs) were reactive for anti-HA significantly more frequently than those with a negative reaction for these markers. In contrast to serologic markers of hepatitis type B, prevalence of anti-HA does not depend on the cause of mental retardation or on the age at primary infection. The rate of anti-HA positivity was found to be closely correlated with duration of institutionalization. The study confirmed that many closed institutions for the mentally retarded are hyperendemic for hepatitis type A and that formation of anti-HA is not greatly affected by either immune deficiency or immune immaturity.
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PMID:Antibody to hepatitis A antigen in institutionalized mentally retarded patients. 13 79

Umbilical cord blood (UCB) is an attractive potential alternative to bone marrow (BM) as a source of hematopoietic progenitor cells since the number of progenitors in UCB is similar or even greater than that in normal BM. It was the aim of the present study to analyze the degree of immaturity of UCB progenitor cells. UCB mononuclear (MNC) and/or CD34+ cells were tested for surface antigen phenotype, expression of cytokines receptor, effect of stem cell factor (SCF) on colony growth, resistance to mafosfamide and replating potential. We have found that 34.9 +/- 3.4% and 77.9 +/- 2.6% of UCB CD34+ cells did not express CD38 and CD45RA antigens, respectively, suggesting that UCB contains a high proportion of immature progenitor cells. By means of three-color analysis, the receptor for SCF was detected on the majority of the CD34+ HLA-DR+ subpopulation; in fact, 81.8% +/- 4.3% of CD34+ HLA-DR+ cells were defined as SCF(low) and 8.1 +/- 1.5% as SCF(high). Colony growth of MNC and CD34+ cells was enhanced by the addition of SCF to methylcellulose mixture, resulting in a statistically significant increase in CFU-GM and CFU-GEMM but not in BFU-E numbers. UCB progenitor cells showed a higher resistance to mafosfamide treatment, in comparison to BM; the addition of SCF to the culture medium resulted in a statistically significant increase in mafosfamide concentration required to inhibit 95% of colony growth (P < or = 0.05). Moreover, as shown by single colony transfer assays, the presence of SCF in primary cultures promoted a significantly higher replating potential for both untreated (42 +/- 3.3% vs 21 +/- 4.6%, P < or = 0.018) and mafosfamide-treated samples (62 +/- 5.6% vs 44 +/- 6.1%, P < or = 0.018). In conclusion, UCB is a source of progenitor cells with immature characteristics in terms of surface antigen expression, distribution of SCF receptor, resistance to mafosfamide and replating potential. Therefore, UCB progenitor cells represent an ideal candidate population for experimental programs involving gene transfer and ex vivo stem cell expansion.
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PMID:Biologic and phenotypic analysis of early hematopoietic progenitor cells in umbilical cord blood. 944 33

Neonates face a high risk of infection because of the immaturity of their immune systems. Although the transplacental transfer of maternal antibodies to the fetus may convey improved postnatal immunity, this transfer occurs late in gestation and may fail to prevent in utero infection. Both fetal immunization and in utero exposure to antigen can result in a state of immunologic tolerance in the neonate. Tolerance induction of fetal and premature infant lymphocytes has become a paradigm for neonatal responsiveness. However, fetal IgM responses have been demonstrated to maternal immunization with tetanus toxoid and to congenital infections such as rubella, toxoplasma, cytomegalovirus and human immunodeficiency virus. Moreover, 1-week-old infants can respond to standard pediatric vaccination, and neonates immunized with polysaccharide antigens do not develop immunologic tolerance. Here, direct immunization of the baboon fetus with recombinant hepatitis B surface antigen produced a specific fetal IgG antibody response. No specific maternal antibody response was detected, eliminating the possibility of vertical antibody transmission to the fetus. Some infants also responded to later vaccinations with hepatitis B surface antigen, indicating that no immunological tolerance was induced by prior fetal immunization. These results characterize the ability of the fetal immune system to respond to in utero vaccination. We demonstrate that active fetal immunization can serve as a safe and efficient vaccination strategy for the fetus and neonate.
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PMID:Fetal immunization of baboons induces a fetal-specific antibody response. 1020 33

Early vaccination is necessary to protect infants from various infectious diseases. However, this is often unsuccessful largely due to the immaturity of the neonatal immune system. Furthermore, maternally derived antibodies can interfere with active immunization. We have previously shown in young mice that immune responses against several different antigens can be improved by the addition of oligodeoxynucleotides containing immunostimulatory CpG motifs (CpG ODN). In this study we have evaluated immunization of newborn (1-7-day-old) BALB/c mice against hepatitis B surface antigen (HBsAg), with alum and/or CpG ODN, in the presence of high levels of maternal antibody against HBsAg (anti-HBs). Seroconversion rates and anti-HBs titers were compared to those induced by a HBsAg-expressing plasmid, since other studies had suggested DNA vaccines to be superior to protein vaccines in young mice with maternal antibody. HBsAg/alum/CpG ODN was superior to DNA vaccine in inducing HBsAg-specific CTL responses in young mice in the presence of maternally transferred anti-HBs antibodies. However, B cell responses to both HBsAg/alum/CpG ODN and DNA vaccines remained weak in the presence of maternally transferred anti-HBs antibodies.
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PMID:Priming of immune responses to hepatitis B surface antigen in young mice immunized in the presence of maternally derived antibodies. 1133 45