HLA-A, -B, -C, -DRB1 and -DQB1 allele and haplotype frequencies in the Serbian population

This study provides the first published detailed analysis of five loci polymorphisms as well as reports of two, three and five loci haplotype frequencies in the Serbian population in a sample of 1992 volunteer bone marrow donors recruited from different part of the country. Typing was performed by PCR SSO method combined with PCR SSP techniques to resolve ambiguities. In total, 16 HLA-A, 28 HLA-B, 14 HLA-C, 13 HLA-DRB1 and 5 HLA-DQB1 allelic groups were identified. The most frequent in allele groups are HLA-A^∗02 (29.5%), HLA-A^∗01 (14.2%), HLA-B^∗35 (13.1%), HLA-B^∗51 (12.8%), HLA-C^∗07 (24.8%), HLA-DRB1^∗11 (16.9%), HLA-DRB1^∗13 (13.2%), HLA-DQB1^∗03 (33.3%) and DQB1^∗05 (33.0%). The most frequent three- and five-loci haplotypes were A^∗01-B^∗08-DRB1^∗03 (5.9%) and A^∗02-B^∗18-DRB1^∗11 (1.9%), A^∗01-B^∗08-C^∗07-DRB1^∗03-DQB1^∗02 (6.6%) followed by A^∗02-B^∗18-C^∗07-DRB1^∗11-DQB1^∗03 (2.5%), then A^∗33-B^∗14-C^∗08-DRB1^∗01-DQB1^∗05 and A^∗02-B^∗35-C^∗04-DRB1^∗16-DQB1^∗05 (2.2% both), respectively. The results of cluster analysis showed that the Serbian population is closely related to the populations living in central Balkan and neighboring European regions. The level of allelic diversity found in this study are relevant to facilitate searching for unrelated matched donor and provide a healthy control population from our region that should be useful in the future disease association study.     

Cytogenetic,spectral karyotyping,fluorescence in situ hybridization,and comparative genomic hybridization characterization of two new secondary leukemia cell lines with 5q deletions,and MYC and MLL amplification

Cytogenetic studies of patients with therapy-induced acute myeloid leukemia (t-AML) have demonstrated whole chromosome loss or q-arm deletion of chromosomes 5 and/or 7 in a majority of cases. We have established two cell lines, SAML-1 and SAML-2, from two patients who developed t-AML after radiation and chemotherapy for Hodgkin disease. In both cases, the leukemia cells contained 5q deletions. SAML-1 has 58 chromosomes and numerous abnormalities, including der(1)(1qter-->1p22::5q31-->5qter), der(5)(5pter-->5q22::1p22-->1pter), +8, der(13)i(13)(q10)del(13)(q11q14.1), and t(10;11). Fluorescence in situ hybridization (FISH) with unique sequence probes for the 5q31 region showed loss of IL4, IL5, IRF1, and IL3, and translocation of IL9, DS5S89, EGR1, and CSFIR to 1p. SAML-2 has 45 chromosomes, del(5)(q11.2q31) with a t(12;13)ins(12;5), leading to the proximity of IRF1 and RB1, and complex translocations of chromosomes 8 and 11, resulting in amplification of MYC and MLL. Comparative genomic hybridization and spectral karyotyping were consistent with the G-banding karyotype and FISH analyses. Because a potential tumor suppressor(s) in the 5q31 region has yet to be identified, these cell lines should prove useful in the study of the mechanisms leading to the development of t-AML.     

Exposure to dexamethasone reduces pituitary volume and gonadotropic cell number in rat fetuses

Overexposure to glucocorticoids during the fetal period induces changes in developmental processes in various fetal tissues. The aim of this study was to investigate the effects of the synthetic glucocorticoid, dexamethasone (Dx), on pituitary volume and gonadotropic cells during a critical period of pituitary development. The effects of Dx on stereological parameters of the pituitary gland and FSH and LH cells were investigated in 19 and 21-day old fetuses. On day 16 of pregnancy, the experimental dams received 1.0 mg Dx/kg b.w. subcutaneously, followed by 0.5 mg Dx/kg b.w./day on days 17 and 18 of gestation. The control gravid females received the same volume of saline. FSH and LH cells were stained immunohistochemically by the peroxidase–antiperoxidase method (PAP). In 19-day old fetuses, exposure to Dx caused a significant decrease of pituitary volume, estimated by Cavalieri's principle. Also, the total number of FSH and LH cells per pituitary, determined by physical fractionator counting technique, was significantly reduced. These changes persisted until fetal day 21. Volume densities and numerical densities of FSH and LH cells after exposure to Dx in 19 and 21-day old fetuses remained unaffected. Our results suggest that altered stereological parameters in pituitary gland after exposure to dexamethasone in fetal period could be long-lasting.     

Expression of kinin B1 and B2 receptors in immature, monocyte-derived dendritic cells and bradykinin-mediated increase in intracellular Ca2+ and cell migration

The kinins, bradykinin (BK) and Lys-des[Arg(9)]-BK, are important inflammatory mediators that act via two specific G protein-coupled kinins, B(1) and B(2) receptors (B(2)R). Kinins influence the activity of immune cells by stimulating the synthesis of cytokines, eicosanoids, and chemotactic factors. Whether human dendritic cells (DC) express kinin receptors and whether kinins influence DC function are unknown. Fluorescence immunocytochemistry and RT-PCR were used to demonstrate that immature human monocyte-derived DC (hMo-DC) constitutively expressed kinins B(1)R and B(2)R. Kinin receptor expression was induced on the 3rd and 4th days of culture during differentiation of hMo-DC from monocytes and was not dependent on the presence of IL-4 or GM-CSF. Although monocytes also expressed B(2)R mRNA, the protein was not detected. The kinin agonists BK and Lys-des[Arg(9)]-BK up-regulated the expression of their respective receptors. BK, acting via the B(2)R, increased intracellular Ca(2+), as visualized by confocal microscopy using the fluorescent Ca(2+) dye, Fluor-4 AM. Evaluation of migration in Trans-well chambers demonstrated significant enhancement by BK of migration of immature hMo-DC, which was B(2)R-dependent. However, kinins did not induce maturation of hMo-DC. The novel finding that kinin receptors are constitutively expressed in immature hMo-DC suggests that these receptors may be expressed in the absence of proinflammatory stimuli. BK, which increases the migration of immature hMo-DC in vitro, may play an important role in the migration of immature DC in noninflammatory conditions and may also be involved in the recruitment of immature DC to sites of inflammation.     

Paracentric inversion involving the long arm of chromosome 9 resulting in deletion of abl gene

We report on a new chromosomal finding in a newborn male with hypertelorism, apparently low-set malformed ears with patent canal, micrognathia with narrow high-arched palate, bilateral webbing of neck with low posterior hairline, widely spaced nipples, and complex heart anomalies. Initially, what appeared to be a simple paracentric inversion of the long arm of chromosome 9, that is, 46,XY, inv(9)(q31q34) by routine GTG-banding technique was later determined to be a paracentric inversion with deletion of the band 9q34.1 by FISH technique using an abl unique sequence DNA probe. Thus the cytogenetic diagnosis was modified to 46,XY,der(9) inv(9)(q31q34.1)del(q34.1). Nevertheless, the presence of telomeric repeat sequences in the inverted chromosome 9 suggests that either healing has occurred by adding [TTAGGG]_n sequences to the nontelomeric end (q31) by the enzyme telomerase or telomeric sequences were not affected during this inversion process. This abnormality is a rare occurrence and has never been reported before either because of a high rate of lethality or it has been undetected by routine cytogenetic techniques. The other abnormal cases with apparent paracentric inversions could also have a complex nature with congenital anomalies associated with loss of “few” DNA sequences as exemplified here. Am. J. Med. Genet. 68:409–411, 1997. © 1997 Wiley-Liss, Inc.     

Diet‐induced obesity increases the frequency of Pig‐a mutant erythrocytes in male C57BL/6J mice

Obesity increases the risk of a number of chronic diseases in humans including several cancers. Biological mechanisms responsible for such increased risks are not well understood at present. Increases in systemic inflammation and oxidative stress, endogenous production of mutagenic metabolites, altered signaling in proliferative pathways, and increased sensitivity to exogenous mutagens and carcinogens are some of the potential contributing factors. We hypothesize that obesity creates an endogenously mutagenic environment in addition to increasing the sensitivity to environmental mutagens. To test this hypothesis, we examined two in vivo genotoxicity endpoints. Pig‐a mutant frequencies and micronucleus frequencies were determined in blood cells in two independent experiments in 30‐week old male mice reared on either a high‐fat diet (60% calories from fat) that exhibit an obese phenotype or a normal‐fat diet (10% calories from fat) that do not exhibit an obese phenotype. Mice were assayed again at 52 weeks of age in one of the experiments. N‐ethyl‐N‐nitrosourea (ENU) was used as a positive mutation control in one experiment. ENU induced a robust Pig‐a mutant and micronucleus response in both phenotypes. Obese, otherwise untreated mice, did not differ from non‐obese mice with respect to Pig‐a mutant frequencies in reticulocytes or micronucleus frequencies. However, such mice, had significantly higher and sustained Pig‐a mutant frequencies (increased 2.5‐3.7‐fold, p < 0.02) in erythrocytes as compared to non‐obese mice (based on measurements collected at 30 weeks or 30 and 52 weeks of age). This suggests that obesity, in the absence of exposure to an exogenous mutagen, is itself mutagenic. Environ. Mol. Mutagen. 57:668–677, 2016. © 2016 Wiley Periodicals, Inc.