Mucocele: A Human Model for Lymphangiogenesis

2009 ◽  
Vol 12 (3) ◽  
pp. 222-228 ◽  
Author(s):  
Eumenia Costa da Cunha Castro ◽  
Csaba Galambos

The mechanism of lymphangiogenesis is poorly understood, and controversy exists whether it is part of the inflammatory response to tissue injury. Utilizing markers specific to lymphatics, we aimed to study if lymphangiogenesis plays a role in the tissue response of mucoceles. Twenty-three extravasated mucoceles were selected. They were grouped by using widely accepted histologic criteria of wound healing into early-, intermediate-, and late-phase lesions. To identify lymphatic vessels we used lymphatic endothelium-specific antibodies (VEGFR3, Prospero-related homeobox gene–1 [Prox-1], and D2–40). To assess the proportion of lymphatic channels to all lesional vessels we used the panendothelial marker CD31. The presence, distribution, and proportion of lymphatic channels were assessed and compared among the groups. To investigate the involvement of lymphangiogenic signals, the expression of VEGFC was determined. To assess for proliferative activity of lymphatic endothelial cells we utilized Ki-67 antibody. Early-phase lesions ( n = 6) were characterized by the presence of centrally located mucicarmine-positive material (mucin pools) with numerous inflammatory cells dominated by mucin-laden CD163-positive macrophages. Only scattered peripheral thin-walled large and small vessels were seen in the stroma surrounding the central mucin pool. Less than half of these vessels were of lymphatic nature as determined by Prox-1, VEGFR3, and D2–40 positivity. The histology of the intermediate-phase lesions ( n = 6) was dominated by numerous lymphatics of varying size, not seen in the early phase. The histology of late-phase lesions ( n = 11) resembled a “pseudo-cyst,” with dense granulation tissue containing rare macrophages and rare lymphatic vessels. Although VEGFC was present in all phases, the highest expression was in the early phase. Low-grade proliferative lymphatic endothelium was noted in the intermediate lesions with a Ki-67 index of 4%. Early lymphangiogenesis and late lymphatic vessel regression were observed during mucocele evolution. The abundant newly formed ectatic lymphatic vessels seen in the intermediate phase may play a role in the clearance of extravasated material (mucin, edema, and lymph fluid) and in the initiation of the young fibroblast-rich granulation tissue. Mucocele appears to be an excellent human model for studying the factors that play a role in new lymphangiogenesis and regression.

2021 ◽  
Vol 22 (6) ◽  
pp. 3105
Author(s):  
Sandeep Silawal ◽  
Benjamin Kohl ◽  
Jingjian Shi ◽  
Gundula Schulze-Tanzil

A central part of the complement system, the anaphylatoxin C5a was investigated in this study to learn its effects on tenocytes in respect to understanding the potential expression of other crucial complement factors and pro-inflammatory mediators involved in tendinopathy. Human hamstring tendon-derived tenocytes were treated with recombinant C5a protein in concentrations of 25 ng/mL and 100 ng/mL for 0.5 h (early phase), 4 h (intermediate phase), and 24 h (late phase). Tenocytes survival was assessed after 24 h stimulation by live-dead assay. The gene expression of complement-related factors C5aR, the complement regulatory proteins (CRPs) CD46, CD55, CD59, and of the pro-inflammatory cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6 was monitored using qPCR. Tenocytes were immunolabeled for C5aR and CD55 proteins. TNFα production was monitored by ELISA. Tenocyte survival was not impaired through C5a stimulation. Interestingly, the gene expression of C5aR and that of the CRPs CD46 and CD59 was significantly reduced in the intermediate and late phase, and that of TNFα only in an early phase, compared to the control group. ELISA analysis indicated a concomitant not significant trend of impaired TNFα protein synthesis at 4 h. However, there was also an early significant induction of CD55 and CD59 mediated by 25 ng/mL anaphylatoxin C5a. Hence, exposure of tenocytes to C5a obviously evokes a time and concentration-dependent response in their expression of complement and pro-inflammatory factors. C5a, released in damaged tendons, might directly contribute to tenocyte activation and thereby be involved in tendon healing and tendinopathy.


2019 ◽  
Vol 8 ◽  
pp. 1511
Author(s):  
Marzieh Shahpari ◽  
Hadi Aligholi ◽  
Mohammad Reza Namavar ◽  
Farzaneh Vafaee ◽  
Masoumeh Emamghoreishi

Background: There is no universally accepted behavioral scoring to define the early development of phenothiazine (PTZ) kindling. Therefore, studies investigating alterations of neurogenesis in the PTZ model were mainly focused on full kindled animals rather than early stages of kindling. This study aimed to determine an appropriate behavioral index for categorizing stages of PTZ kindling progress and to evaluate neurogenesis during PTZ kindling. Materials and Methods: Twenty-four mice were intraperitoneally injected with a sub convulsive dose of PTZ (40mg/kg) every other day until they became full kindled. The first occurrence of different seizure behaviors and their durations were recorded during kindling development, and the different stages of kindling were categorized. Neurogenesis was evaluated in the lateral subventricular zone (SVZ) at each stage of kindling by immunofluorescence staining. Results: First occurrence of restlessness, motionless staring, hind limb tonic extension, Straub’s tail, myoclonic jerk, and tonic-clonic were sequentially observed in more than 80% of animals with increasing PTZ injections. The duration of the myoclonic jerk was significantly longer than the other seizure behaviors. The significantly higher percentage of BrdU-positive cells was found in SVZ of mice showing tonic-clonic in comparison to other seizure behaviors. Conclusion: A hierarchy behavior was observed during the kindling process when considering the first occurrence of seizure behaviors. We defined the first occurrence of restlessness, motionless, hind limb tonic extension and Straub’s tail behaviors as an early phase, myoclonic jerk as a borderline phase and tonic-clonic as a late phase of PTZ-induced kindling. Our results indicated an enhanced SVZ neurogenesis at the late phase of kindling. [GMJ.2019;8:e1511]


2019 ◽  
Vol 9 (8) ◽  
pp. 1615 ◽  
Author(s):  
Cristian Bogdan Iancu ◽  
Mugurel Constantin Rusu ◽  
Laurenţiu Mogoantă ◽  
Sorin Hostiuc ◽  
Oana Daniela Toader

A great interest has developed over the last several years in research on interstitial Cajal-like cells (ICLCs), later renamed to telocytes (TCs). Such studies are restricted by diverse limitations. We aimed to critically review (sub)epicardial ICLCs/TCs and to bring forward supplemental immunohistochemical evidence on (sub)epicardial stromal niche inhabitants. We tested the epicardial expressions of CD117/c-kit, CD34, Cytokeratin 7 (CK7), Ki67, Platelet-Derived Growth Factor Receptor (PDGFR)-α and D2-40 in adult human cardiac samples. The mesothelial epicardial cells expressed D2-40, CK7, CD117/c-kit and PDGFR-α. Subepicardial D2-40-positive lymphatic vessels and isolated D2-40-positive and CK7-positive subepicardial cells were also found. Immediate submesothelial spindle-shaped cells expressed Ki-67. Submesothelial stromal cells and endothelial tubes were PDGFR-α-positive and CD34-positive. The expression of CD34 was pan-stromal, so a particular stromal cell type could not be distinguished. The stromal expression of CD117/c-kit was also noted. It seems that epicardial TCs could not be regarded as belonging to a unique cell type until (pre)lymphatic endothelial cells are inadequately excluded. Markers such as CD117/c-kit or CD34 seem to be improper for identifying TCs as a distinctive cell type. Care should be taken when using the immunohistochemical method and histological interpretations, as they may not produce accurate results.


Author(s):  
Yuting Tang ◽  
Xiaofang Lin ◽  
Cheng Chen ◽  
Zhongyi Tong ◽  
Hui Sun ◽  
...  

Background: Nucleolin has multiple functions within cell survival and proliferation pathways. Our previous studies have revealed that nucleolin can significantly reduce myocardial ischemia-reperfusion injury by promoting myocardial angiogenesis and reducing myocardial apoptosis. In this study, we attempted to determine the role of nucleolin in myocardial infarction (MI) injury recovery and the underlying mechanism. Methods: Male BALB/c mice aged 6–8 weeks were used to set up MI models by ligating the left anterior descending coronary artery. Nucleolin expression in the heart was downregulated by intramyocardial injection of a lentiviral vector expressing nucleolin-specific small interfering RNA. Macrophage infiltration and polarization were measured by real-time polymerase chain reaction, flow cytometry, and immunofluorescence. Cytokines were detected by enzyme-linked immunosorbent assay. Results: Nucleolin expression in myocardium after MI induction decreased a lot at early phase and elevated at late phase. Nucleolin knockdown impaired heart systolic and diastolic functions and decreased the survival rate after MI. Macrophage infiltration increased in the myocardium after MI. Most macrophages belonged to the M1 phenotype at early phase (2 days) and the M2 phenotype increased greatly at late phase after MI. Nucleolin knockdown in the myocardium led to a decrease in M2 macrophage polarization with no effect on macrophage infiltration after MI. Furthermore, Notch3 and STAT6, key regulators of M2 macrophage polarization, were upregulated by nucleolin in RAW 264.7 macrophages. Conclusions: Lack of nucleolin impaired heart function during recovery after MI by reducing M2 macrophage polarization. This finding probably points to a new therapeutic option for ischemic heart disease.


BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Takao Watanabe ◽  
Yoshio Tokumoto ◽  
Kouji Joko ◽  
Kojiro Michitaka ◽  
Norio Horiike ◽  
...  

Abstract Background An unexpected recurrence of hepatocellular carcinoma (HCC) sometimes occurs in patients with hepatitis C virus (HCV) after treatment with direct-acting antivirals (DAAs). However, the characteristics of patients with HCC recurrence may differ depending on time after DAA treatment. We aimed to identify risk factors related to HCC recurrence according to time after DAA treatment. Methods Of 1663 patients with HCV treated with a DAA, 199 patients had a previous history of HCC. We defined HCC recurrence within 1 year after DAA treatment as ‘early recurrence’, and recurrence more than 1 year after as ‘late recurrence’. The different risk factors between the early and late phases of HCC recurrence after the end of DAA therapy were investigated. Results Ninety-seven patients experienced HCC recurrence during the study period. Incidences of recurrence were 29.8, 41.0, and 53.4% at 1, 2, and 3 years, respectively, after the end of DAA therapy. Multivariate analysis identified post-treatment α-fetoprotein (AFP) as an independent factor contributing to HCC recurrence in the early phase (hazard ratio, 1.056; 95% confidence interval, 1.026–1.087, p < 0.001) and post-treatment estimated glomerular filtration rate (eGFR) (hazard ratio, 0.98; 95% confidence interval, 0.96–0.99, p = 0.032) as a predictor of HCC recurrence in the late phase. Conclusion Patients with higher post-treatment AFP in the early phase and those with lower post-treatment eGFR in the late phase had a high risk of HCC recurrence. The risk factors associated with HCC recurrence after DAA treatment were different between the early and late phases.


2015 ◽  
Vol 2015 ◽  
pp. 1-4 ◽  
Author(s):  
Omer Alici ◽  
Musa Kemal Keles ◽  
Alper Kurt

Proliferating trichilemmal tumors (PTTs) are neoplasms derived from the outer root sheath of the hair follicle. These tumors, which commonly affect the scalp of elderly women, rarely demonstrate malignant transformation. Although invasion of the tumors into neighboring tissues and being accompanied with anaplasia and necrosis are accepted as findings of malignancy, histological features may not always be sufficient to identify these tumors. The clinical behavior of the tumor may be incompatible with its histological characteristics. Squamous-cell carcinoma should certainly be considered in differential diagnosis because of its similarity in morphological appearance with PTT. Immunostaining for CD34, P53, and Ki-67 is a useful adjuvant diagnostic method that can be used in differential diagnosis aside from morphological findings. In this study, we aimed to present the case of a 52-year-old female patient with clinicopathological features. We reported a low-grade malignant proliferating trichilemmal tumor in this patient and detected no relapse or metastasis in a 24-month period of follow-up.


1993 ◽  
Vol 13 (4) ◽  
pp. 2411-2419
Author(s):  
K P Mann ◽  
E A Weiss ◽  
J R Nevins

The recognition and processing of a pre-mRNA to create a poly(A) addition site, a necessary step in mRNA biogenesis, can also be a regulatory event in instances in which the frequency of use of a poly(A) site varies. One such case is found during the course of an adenovirus infection. Five poly(A) sites are utilized within the major late transcription unit to produce more than 20 distinct mRNAs during the late phase of infection. The proximal half of the major late transcription unit is also expressed during the early phase of a viral infection. During this early phase of expression, the L1 poly(A) site is used three times more frequently than the L3 poly(A) site. In contrast, the L3 site is used three times more frequently than the L1 site during the late phase of infection. Recent experiments have suggested that the recognition of the poly(A) site GU-rich downstream element by the CF1 processing factor may be a rate-determining step in poly(A) site selection. We demonstrate that the interaction of CF1 with the L1 poly(A) site is less stable than the interaction of CF1 with the L3 poly(A) site. We also find that there is a substantial decrease in the level of CF1 activity when an adenovirus infection proceeds to the late phase. We suggest that this reduction in CF1 activity, coupled with the relative instability of the interaction with the L1 poly(A) site, contributes to the reduced use of the L1 poly(A) site during the late stage of an adenovirus infection.


1984 ◽  
Vol 4 (5) ◽  
pp. 966-972
Author(s):  
C Montell ◽  
E F Fisher ◽  
M H Caruthers ◽  
A J Berk

The primary transcript from adenovirus 2 early region 1B (E1B) is processed by differential RNA splicing into two overlapping mRNAs, 13S and 22S. The 22S mRNA is the major E1B mRNA during the early phase of infection, whereas the 13S mRNA predominates during the late phase. In previous work, it has been shown that this shift in proportions of the E1B mRNAs is influenced by increased cytoplasmic stability of the 13S mRNA at late times in infection. Two observations presented here demonstrate that the increase in proportion of the 13S mRNA at late times is also regulated by a change in the specificity of RNA splicing. First, the relative concentrations of the 13S to 22S nuclear RNAs were not constant throughout infection but increased at late times. Secondly, studies with the mutant, adenovirus 2 pm2250 , provided evidence that there was an increased propensity to utilize a 5' splice in the region of the 13S 5' splice site at late times in infection. Adenovirus 2 pm2250 has a G----C transversion in the first base of E1B 13S mRNA intron preventing splicing of the 13S mRNA but not of the 22S mRNA. During the early phase of a pm2250 infection, the E1B primary transcripts were processed into the 22S mRNA only. However, during the late phase, when the 13S mRNA normally predominates, E1B primary transcripts were also processed by RNA splicing at two formerly unused or cryptic 5' splice sites. Both cryptic splice sites were located much closer to the disrupted 13S 5' splice site than to the 22S 5' splice site. Thus, the temporal increase in proportion of the 13S mRNA to the 22S mRNA is regulated by two processes, an increase in cytoplasmic stability of the 13S mRNA and an increased propensity to utilize the 13S 5' splice site during the late phase of infection. Adenovirus 2 pm2250 was not defective for productive infection of HeLa cells or for transformation of rat cells.


Sign in / Sign up

Export Citation Format

Share Document