Measurement of telomere length in haematopoietic cells using in situ hybridization techniques

2000 ◽  
Vol 28 (2) ◽  
pp. 245-250 ◽  
Author(s):  
U. M. Martens ◽  
V. Brass ◽  
M. Engelhardt ◽  
S. Glaser ◽  
C. F. Waller ◽  
...  

The DNA of human chromosomes terminates in several kilobases of telomere repeats that are gradually lost with age and with replication in vitro. Defective telomere maintenance has been shown to be causally linked to cell cycle exit and apoptosis. In order to overcome the limitations imposed by Southern blotting, we have established a quantitative fluorescence in situ hybridization (Q-FISH) technique. This technique allows estimation of telomere length in specific chromosome arms from metaphase cell preparations. Furthermore, we have extended quantitative in situ hybridization to flow cytometry (flow FISH) in order to obtain information on the mean telomere repeat content in suspended cells. Telomere length in granulocytes, monocytes, CD8 and CD4 T lymphocytes and natural killer cells was found to differ slightly in the peripheral blood of adults. However, strikingly longer telomeres were observed in B lymphocytes (∼ 1.3 kb longer), suggesting a functional role for telomere maintenance in this cell subset. In summary, Q-FISH and flow FISH represent new methods for measuring telomere length in single cells and allow studies of telomere dynamics in haematopoietic subpopulations at various stages of normal and abnormal antigen responses.

Blood ◽  
2007 ◽  
Vol 110 (5) ◽  
pp. 1439-1447 ◽  
Author(s):  
Blanche P. Alter ◽  
Gabriela M. Baerlocher ◽  
Sharon A. Savage ◽  
Stephen J. Chanock ◽  
Babette B. Weksler ◽  
...  

Abstract Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome in which the known susceptibility genes (DKC1, TERC, and TERT) belong to the telomere maintenance pathway; patients with DC have very short telomeres. We used multicolor flow fluorescence in situ hybridization analysis of median telomere length in total blood leukocytes, granulocytes, lymphocytes, and several lymphocyte subsets to confirm the diagnosis of DC, distinguish patients with DC from unaffected family members, identify clinically silent DC carriers, and discriminate between patients with DC and those with other bone marrow failure disorders. We defined “very short” telomeres as below the first percentile measured among 400 healthy control subjects over the entire age range. Diagnostic sensitivity and specificity of very short telomeres for DC were more than 90% for total lymphocytes, CD45RA+/CD20− naive T cells, and CD20+ B cells. Granulocyte and total leukocyte assays were not specific; CD45RA− memory T cells and CD57+ NK/NKT were not sensitive. We observed very short telomeres in a clinically normal family member who subsequently developed DC. We propose adding leukocyte subset flow fluorescence in situ hybridization telomere length measurement to the evaluation of patients and families suspected to have DC, because the correct diagnosis will substantially affect patient management.


2018 ◽  
Vol 66 (7) ◽  
pp. 485-495 ◽  
Author(s):  
Aernoud A. van Batenburg ◽  
Karin M. Kazemier ◽  
Ton Peeters ◽  
Matthijs F. M. van Oosterhout ◽  
Joanne J. van der Vis ◽  
...  

Telomeres are small repetitive DNA sequences at the ends of chromosomes which act as a buffer in age-dependent DNA shortening. Insufficient telomere repeats will be recognized as double-strand breaks. Presently, it is becoming more evident that telomere attrition, whether or not caused by mutations in telomere maintenance genes, plays an important role in many inflammatory and age-associated diseases. In this report, a method to (semi)quantitatively assess telomere length and DNA double-strand breaks in formalin-fixed paraffin-embedded (FFPE) tissue is described. Therefore, a novel combination of quantitative fluorescence in situ hybridization, tissue elution, and immunofluorescence staining techniques was developed. Caveolin-1 (type 1 pneumocytes), pro-surfactant protein C (type 2 pneumocytes), club cell-10 (club cells), and alpha smooth muscle actin (smooth muscle cells) markers were used to identify cell types. To visualize all the different probes, restaining the tissue by heat-mediated slide elution is essential. Fluorescent signals of telomeres and DNA double-strand breaks were quantified using the Telometer plugin of ImageJ. As example, we analyzed lung tissue from a familial pulmonary fibrosis patient with a mutation in the telomere-associated gene poly(A)-specific ribonuclease ( PARN). The protocol displays a novel opportunity to directly quantitatively link DNA double-strand breaks to telomere length in specific FFPE cells.


2020 ◽  
Vol 27 (5) ◽  
pp. 432-446
Author(s):  
Akiko Yamamoto ◽  
Ken-ichiro Matsunaga ◽  
Toyoaki Anai ◽  
Hitoshi Kawano ◽  
Toshihisa Ueda ◽  
...  

Background: Intermediate Filaments (IFs) are major constituents of the cytoskeletal systems in animal cells. Objective: To gain insights into the structure-function relationship of invertebrate cytoplasmic IF proteins, we characterized an IF protein from the platyhelminth, Dugesia japonica, termed Dif-1. Method: cDNA cloning, in situ hybridization, immunohistochemical analysis, and IF assembly experiments in vitro using recombinant Dif-1, were performed for protein characterization. Results: The structure deduced from the cDNA sequence showed that Djf-1 comprises 568 amino acids and has a tripartite domain structure (N-terminal head, central rod, and C-terminal tail) that is characteristic of IF proteins. Similar to nuclear IF lamins, Djf-1 contains an extra 42 residues in the coil 1b subdomain of the rod domain that is absent from vertebrate cytoplasmic IF proteins and a nuclear lamin-homology segment of approximately 105 residues in the tail domain; however, it contains no nuclear localization signal. In situ hybridization analysis showed that Djf-1 mRNA is specifically expressed in cells located within the marginal region encircling the worm body. Immunohistochemical analysis showed that Djf-1 protein forms cytoplasmic IFs located close to the microvilli of the cells. In vitro IF assembly experiments using recombinant proteins showed that Djf-1 alone polymerizes into IFs. Deletion of the extra 42 residues in the coil 1b subdomain resulted in the failure of IF formation. Conclusions: Together with data from other histological studies, our results suggest that Djf- 1 is expressed specifically in anchor cells within the glandular adhesive organs of the worm and that Djf-1 IFs may play a role in protecting the cells from mechanical stress.


Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1502
Author(s):  
Jorge García-Hernández ◽  
Manuel Hernández ◽  
Yolanda Moreno

Vibrio parahaemolyticus is a human food-borne pathogen with the ability to enter the food chain. It is able to acquire a viable, non-cultivable state (VBNC), which is not detected by traditional methods. The combination of the direct viable count method and a fluorescent in situ hybridization technique (DVC-FISH) makes it possible to detect microorganisms that can present VBNC forms in complex samples The optimization of the in vitro DVC-FISH technique for V. parahaemolyticus was carried out. The selected antibiotic was ciprofloxacin at a concentration of 0.75 μg/mL with an incubation time in DVC broth of 5 h. The DVC-FISH technique and the traditional plate culture were applied to detect and quantify the viable cells of the affected pathogen in artificially contaminated food matrices at different temperatures. The results obtained showed that low temperatures produced an important logarithmic decrease of V. parahaemolyticus, while at 22 °C, it proliferated rapidly. The DVC-FISH technique proved to be a useful tool for the detection and quantification of V. parahaemolyticus in the two seafood matrices of oysters and mussels. This is the first study in which this technique has been developed to detect viable cells for this microorganism.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Fiorella Ghisays ◽  
Aitor Garzia ◽  
Hexiao Wang ◽  
Claudia Canasto-Chibuque ◽  
Marcel Hohl ◽  
...  

AbstractTelomere repeat containing RNAs (TERRAs) are a family of long non-coding RNAs transcribed from the subtelomeric regions of eukaryotic chromosomes. TERRA transcripts can form R-loops at chromosome ends; however the importance of these structures or the regulation of TERRA expression and retention in telomeric R-loops remain unclear. Here, we show that the RTEL1 (Regulator of Telomere Length 1) helicase influences the abundance and localization of TERRA in human cells. Depletion of RTEL1 leads to increased levels of TERRA RNA while reducing TERRA-containing R loops at telomeres. In vitro, RTEL1 shows a strong preference for binding G-quadruplex structures which form in TERRA. This binding is mediated by the C-terminal region of RTEL1, and is independent of the RTEL1 helicase domain. RTEL1 binding to TERRA appears to be essential for cell viability, underscoring the importance of this function. Degradation of TERRA-containing R-loops by overexpression of RNAse H1 partially recapitulates the increased TERRA levels and telomeric instability associated with RTEL1 deficiency. Collectively, these data suggest that regulation of TERRA is a key function of the RTEL1 helicase, and that loss of that function may contribute to the disease phenotypes of patients with RTEL1 mutations.


1987 ◽  
Vol 35 (8) ◽  
pp. 837-842 ◽  
Author(s):  
H Kreipe ◽  
H J Radzun ◽  
K Heidorn ◽  
C Mäder ◽  
M R Parwaresch

The cellular homologue of the retroviral oncogene v-fos has been shown to be involved in cell differentiation of hematopoietic cells. By use of the human promyelocyte cell line HL-60, several in vitro differentiation studies suggested a selective activation of c-fos during monocytic differentiation of myeloid precursor cells. In contrast to these observations, we found high levels of c-fos mRNA in purified normal human granulocytes, whereas c-fos was only faintly expressed in blood monocytes. In situ hybridization revealed that the high level of c-fos expression is restricted to neutrophilic granulocytes, whereas c-fos transcription is not detectable in eosinophilic granulocytes. These results indicate that in vitro differentiation systems can be misleading and may not reflect the in vivo situation. The high level of c-fos expression in neutrophilic granulocytes may be caused by superinduction due to the reduced capacity for protein synthesis in these cells.


2007 ◽  
Vol 15 (3) ◽  
pp. 399-408 ◽  
Author(s):  
Gianfranco Coppola ◽  
Basil Alexander ◽  
Dino Di Berardino ◽  
Elizabeth St John ◽  
Parvathi K. Basrur ◽  
...  

2018 ◽  
Vol 9 (1) ◽  
Author(s):  
Rohan T. Ranasinghe ◽  
Martin R. Challand ◽  
Kristina A. Ganzinger ◽  
Benjamin W. Lewis ◽  
Charlotte Softley ◽  
...  

1993 ◽  
Vol 4 (6) ◽  
pp. 342-345 ◽  
Author(s):  
S L Patrick ◽  
T C Wright ◽  
H E Fox ◽  
H S Ginsberg

Women are infected with HIV in increasing numbers; the predominant mode of spread is through heterosexual transmission. Little is known regarding the mechanism of HIV transit through the female genital tract. We investigated whether early passaage cervical epithelial cells could be directly infected with HIV-1LAI*. Virus production was measured using the reverse transcriptase (RT) assay and direct assay for syncytia-forming units. In-situ hybridization was performed on infected cervical cell cultures. Immunostaining was carried out using a monoclonal antibody to leukocyte common antigen (LCA). Virus was recovered in the supernatants of all infected cervical cultures. Localization of HIV infection using in-situ hybridization identified rare cells in the population which gave a strong signal. These infected cells had a lymphoid morphology and were also detected using immunostaining for LAC. Cervical epithelial cells were uninfected in this in vitro model; cells in this population which supported viral replication were most likely of the macrophage/monocyte lineage.


Sign in / Sign up

Export Citation Format

Share Document