Polymerase chain reaction screening of immunoglobulin heavy chain and T cell receptor γ gene rearrangements: A practical approach to molecular DNA analysis of non-Hodgkin's lymphoma in a surgical pathology laboratory

Characterization of the clonality of non-Hodgkin's lymphoma (NHL) by the rearranged segments of immunoglobulin heavy chain (Ig(H)) or T cell receptor (TCR) genes is not only useful in the confirmation of the diagnosis but also for the future assessment of how a secondary lymphoma, such as a recurrence or another primary lymphoma, occurs. As a practical approach to obtaining and registering this information in a surgical pathology laboratory, FR3 and FR1 regions of Ig(H) gene and TCRgamma gene were concurrently amplified by polymerase chain reaction (PCR) using each pair of consensus primers and the same PCR protocol. Examined samples consisted of 134 primary NHL (phenotypically, 108 B cell and 26 T cell NHL), 19 reactive lymphadenopathies, as well as five secondary lymphomas whose primary lesions were included in this study. Among the primary NHL, the combined PCR analysis disclosed the clonality in 103 of 134 NHL (77%), by FR3 PCR in 77 B cell and two T cell NHL, by FR1 PCR in 59 B cell and one T cell NHL, and by TCRgamma PCR in 11 B cell and 17 of 26 T cell NHL, but in none of the reactive lymphadenopathies. Among the secondary lymphomas, the same pattern of PCR analysis was obtained in two cases (the durations between first and second lymphomas; 6 and 10 months), which suggested recurrence. In contrast, different results were obtained in three cases (17-37 months), which indicated another primary or emergence of the subclones. The results of Southern blot analysis were concordant with the PCR results of the first and the secondary lymphomas. Although the combined PCR analysis cannot replace Southern blot hybridization because of its lower detection rate, it can select those cases suitable for further Southern blot analysis thus reducing the number of unnecessary examinations by nearly 75%. This approach may also be useful in the comparative evaluation of primary and secondary lymphomas.     

Mutational analysis of the human SLC26A8 gene: exclusion as a candidate for male infertility due to primary spermatogenic failure

SLC26A8 is an anion transporter that is solely expressed in the testes. It interacts with MgcRacGAP that shows strong structural similarity with the Drosophila protein RotundRacGAP, which is established to have an essential role for male fertility in the fruit fly. To explore whether the SLC26A8 gene has a role in human male infertility, we performed mutational analysis in the coding region of the SLC26A8 gene in 83 male infertility patients and two groups of controls using single-strand conformational polymorphism and direct sequencing methods. We found six novel coding sequence variations, of which five lead to amino acid substitutions. All variants were found with similar frequencies in both patients and controls, thus suggesting that none of them may be causally associated with infertility. We conclude that the SLC26A8 mutations are not a common cause of male infertility.     

Genetics and human conception: DNA-based X-enriched sperm separation as an adjunct to preimplantation genetic testing for the prevention of X-linked disease

We report the world's first clinical pregnancy resulting fromDNA-based enrichment for X-bearing human spermatozoa, for preventionof X-linked hydrocephalus. Sperm separation was followed byembryo biopsy and nested multiplex polymerase chain reaction(PCR) for gender determination. Enriched populations of X-bearingspermatozoa ranging from 80 to 89% pure as determined by fluorescencein-situ hybridization (FISH) resulted in in-vitro fertilization(IVF) rates indistinguishable from normal IVF procedures (65%).In two separate biopsy procedures, 7/9 and 15/16 of the resultingembryos were determined to be female by multiplex PCR. Embryotransfer resulted in a karyotypically normal female fetus. Thistechnique should be widely applicable to gender selection forthe prevention of genetic disorders.     

Electron microscopy of an alpha-dystroglycan fragment containing receptor sites for lymphocytic choriomeningitis virus and laminin, and use of the receptoid body as a reagent to neutralize virus

We report the electron microscopic structure of an alpha-dystroglycan (alpha-DG) fragment (DGEKFc4) that contains binding sites for lymphocytic choriomeningitis virus (LCMV) and the extracellular matrix (ECM) molecule laminin. In electron microscopic images, DGEKFc4 appears as dumbbell-shaped rods with a length of 7.5 +/- 0.5 nM and width of 3 +/- 0.3 nM. The C-terminal human Fc allows binding of anti-human Fc antibody resulting in formation of immune complexes that preserve alpha-DG binding to virus. Electron microscopy shows the antibody binding to near one end of the dumbbell-shaped rods. Because arenaviruses like LCMV or Lassa fever virus (LFV) generate poor neutralizing antibodies during natural infection or vaccination, we assayed whether the alpha-DG receptoid bodies generated could be used as an efficient antibody mimic. However, the receptor body formed by either alpha-DG fragment alone or complexed to antibody to human Fc failed to efficiently neutralize virus.     

Evaluation of the possible association of body mass index and four metabolic gene polymorphisms with longevity in an Italian cohort: a role for APOE,eNOS and FTO gene polymorphisms

Abstract

Background: Longevity is considered the result of interactions between environmental and genetic factors.

Aim: To investigate the possible association of body mass index and the frequencies of APOE, ACE, eNOS and FTO gene polymorphisms with longevity.

Subjects and methods: In total, 1100 healthy volunteers aged 10–100 were recruited. Subjects were genotyped for APOE, ACE, eNOS and FTO gene polymorphisms. Data about height and weight were also collected. The sample was split into four age groups: 1–24, 25–49, 50–85 and 86–100 years.

Results: Significant differences were found in BMI values between age groups. A significant decrease of the APOE4, eNOS 393 and FTO A and allele frequencies was observed in the 86–100 age group compared to the younger groups. For ACE gene, no significant differences were found in the allele frequencies between groups. A similar trend was also observed when the sample was subdivided into two main age groups: 1–85 and 86–100 years.

Conclusion: This study provides evidence for a role of APOE, eNOS and FTO gene polymorphisms in longevity. It has been estimated that the number of centenarians worldwide will double each decade until 2100, making population data about gene polymorphisms relevant for further studies about longevity.     

Dehydroepiandrosterone (DHEA) as a possible source for estrogen formation in bone cells: correlation between bone mineral density and serum DHEA-sulfate concentration in postmenopausal women,and the presence of aromatase to be enhanced by 1,25-dihydroxyvitamin D3 in human osteoblasts

A significant positive correlation between bone mineral density (BMD) and serum dehydroepiandrosterone sulfate (DHEA-S) was found in 120 postmenopausal women (51-99 years old) but no correlation was seen between BMD and serum estradiol. In subset analysis, strong positive correlation of serum DHEA-S and estrone with BMD was observed in postmenopausal women aged less than 69 years old. To study a possible role of DHEA-S in preventing osteoporosis, we characterized aromatase activity converting androgens to estrogens in human osteoblasts, because postmenopausal women maintain considerable levels of adrenal androgens. Glucocorticoids at 10(-9) to 10(-7) M induced transiently the expression of and the enzymatic activity of aromatase cytochrome P450 (P450AROM) in primary cultured osteoblasts. 1,25-Dihydroxyvitamin D3 (1,25-(OH)(2)D(3)) alone did not induce the aromatase activity, but enhanced and maintained the glucocorticoid-induced P450AROM gene expression. Analysis of the activity of P450AROM gene 1b (I.4) promoter, which is used dominantly in human osteoblasts, indicated that the region from -888 bp to -500 bp, which does not contain a typical vitamin D responsive element, is responsible for the enhancing effect of 1,25-(OH)(2)D(3). These results may suggest that adrenal androgen, DHEA, is converted to estrone in osteoblast by P450AROM, which is positively regulated by glucocorticoid and 1,25-(OH)(2)D(3), and is important in maintaining BMD in the sixth to the seventh decade, after menopause.     

Identification of germ cells at risk for neoplastic transformation in gonadoblastoma: an immunohistochemical study for OCT3/4 and TSPY

Carcinoma in situ (CIS) is the precursor of malignant testicular germ cell tumors (GCTs) of adolescents and young adults, being the neoplastic counterpart of primordial germ cells/gonocytes. Carcinoma in situ cells will develop into invasive seminoma/nonseminoma. Gonadoblastoma (GB) is the precursor of invasive GCTs in dysgenetic gonads, predominantly dysgerminoma (DG). In this process, part of the Y chromosome (GBY region) is involved, for which TSPY is a candidate gene. A detailed immunohistochemical survey was performed for the known diagnostic markers, germ cell/placental alkaline phosphatase (PLAP), c-KIT, and OCT3/4, as well as testis-specific protein on the Y chromosome (TSPY) on a series of GBs, and adjacent invasive DGs. All 5 patients were XY individuals (4 females and 1 male). In contrast to c-KIT, PLAP was positive in all cases. The immature germ cells of GBs were positive for OCT3/4, whereas the mature germ cells were negative for this marker, but positive for TSPY. In every GB, a minor population of germ cells positive for both markers could be identified, similar to most CIS cells and early invasive DG. On progression to an invasive tumor, TSPY can be lost, a process that is also detectable in invasive testicular GCTs compared to CIS. These results indicate that GB is a heterogeneous mix of germ cells, in which the OCT3/4-positive cells have the potential to undergo progression to an invasive tumor. These early invasive stages are initially also positive for TSPY (like CIS), supporting a positive selection mechanism. Therefore, OCT3/4 in combination with TSPY is valuable to identify malignant germ cells in dysgenetic gonads. This could allow better prediction of the risk of progression to a GCT. In addition, the data support the model that GB represents the earliest accessible developmental stage of malignant GCTs.     

An emerging role of neutrophils and NETosis in chronic inflammation and fibrosis in systemic lupus erythematosus (SLE) and ANCA-associated vasculitides (AAV): Implications for the pathogenesis and treatment

Neutrophils derive from hematopoietic stem cells (HSCs) with systemic inflammation driving their activation and differentiation to myeloid progenitors to ensure enhanced myelopoiesis. Epigenetic reprograming and re-education of these HSCs produces neutrophils primed towards elimination of pathogens and increased inflammatory response. Neutrophils -an important component of acute inflammation- are not present in chronic inflammatory tissues leading to the false assumption that they may not be as important for the latter. Activated neutrophils may release Neutrophil Extracellular Traps (NETs) during a distinct form of cell death, named NETosis; NETs are rich in bioactive molecules that promote thrombosis (including atherothrombosis), inflammation and fibrosis. Thus, although neutrophils may not be present in chronic inflammatory lesions, their remnants may amplify the inflammatory response beyond their short life-span in the tissues. Herein, we review current evidence supporting a role of neutrophils and NETosis in tissue injury and dysfunction in systemic autoimmunity using as disease paradigms Systemic Lupus Erythematosus (SLE) and the ANCA-associated vasculitides (AAV). We also discuss the mechanisms involved and their potential as targets for novel therapy and drug repositioning.