scholarly journals Microbiomes of Clownfish and Their Symbiotic Host Anemone Converge Before Their First Physical Contact.

2021 ◽  
Author(s):  
Émie Audet-Gilbert ◽  
François-Étienne Sylvain ◽  
Sidki Bouslama ◽  
Nicolas Derome
Keyword(s):  
Molecular Mimicry ◽  
Water System ◽  
Physical Contact ◽  
Physical Interaction ◽  
Skin Microbiota ◽  
Chemical Camouflage ◽  
Heteractis Magnifica ◽  
Host Anemone ◽  
Remote Interaction ◽  
Interaction Period

Abstract BackgroundOne of the most charismatic, and yet not completely resolved example of mutualistic interaction is the partnership of clownfish and its symbiotic sea anemone. The mechanism explaining this tolerance currently relies on the molecular mimicry of clownfish epithelial mucus, which could serve as camouflage, preventing the anemone's nematocysts' discharge. Resident bacteria are known as key drivers of epithelial mucus chemical signature in vertebrates. A recent study has proposed a restructuration of the skin microbiota in a generalist clown fish when first contacting its symbiotic anemone. We explored a novel hypothesis by testing the effect of remote interaction on epithelial microbiota restructuration in both partners. MethodsWith metataxonomics, we investigated the epithelial microbiota dynamic of 18 pairs of percula clownfish (Amphiprion percula) and their symbiotic anemone Heteractis magnifica in remote interaction, physical interaction and control groups for both partners during a four weeks trial.ResultsPhysical and Remote Interaction groups’ results evidence gradual epithelial microbiota convergence between both partners when fish and anemone were placed in the same water system. This convergence occurred preceding any physical contact between partners, and was maintained during the two-weeks interaction period in both contact groups. After the interaction period, community structure of both fish and anemone’s epthelial community structures maintained the interaction signature two weeks after fish-anemone pairs separation. Furthermore, the interaction signature persistence was observed both in Physical and Remote Interaction groups, thus suggesting that water-mediated chemical communication between symbiotic partners was strong enough to shift the skin microbiota durably, even after the separation of fish-anemone pairs. Finally, our results suggest that fish-anemone convergent microbiota restructuration was increasingly associated with the parallel recruitment of three Flavobacteriaceae strains closely related to a tyrosinase-producing Cellulophaga tyrosinoxydans. ConclusionsOur study shows that bacterial community restructuration, in the acclimation process, does not only rely on direct physical contact. Furthermore, our results challenge, for the first time, the traditional unidirectional chemical camouflage hypothesis, as we argue that convergence of the epithelial microbiota of both partners may play essential roles in establishing mutual acceptance.

scholarly journals Microbiomes of clownfish and their symbiotic host anemone converge before their first physical contact

Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Audet-Gilbert Émie ◽  
Sylvain François-Étienne ◽  
Bouslama Sidki ◽  
Derome Nicolas
Keyword(s):  
Molecular Mimicry ◽  
Water System ◽  
Physical Contact ◽  
Physical Interaction ◽  
Skin Microbiota ◽  
Chemical Camouflage ◽  
Heteractis Magnifica ◽  
Host Anemone ◽  
Remote Interaction ◽  
Interaction Period

Abstract Background One of the most charismatic, and yet not completely resolved example of mutualistic interaction is the partnership of clownfish and its symbiotic sea anemone. The mechanism explaining this tolerance currently relies on the molecular mimicry of clownfish epithelial mucus, which could serve as camouflage, preventing the anemone's nematocysts' discharge. Resident bacteria are known as key drivers of epithelial mucus chemical signature in vertebrates. A recent study has proposed a restructuration of the skin microbiota in a generalist clown fish when first contacting its symbiotic anemone. We explored a novel hypothesis by testing the effect of remote interaction on epithelial microbiota restructuration in both partners. Methods With metataxonomics, we investigated the epithelial microbiota dynamic of 18 pairs of percula clownfish (Amphiprion percula) and their symbiotic anemone Heteractis magnifica in remote interaction, physical interaction and control groups for both partners during a 4-week trial. Results The Physical and Remote Interaction groups’ results evidence gradual epithelial microbiota convergence between both partners when fish and anemone were placed in the same water system. This convergence occurred preceding any physical contact between partners, and was maintained during the 2-week interaction period in both contact groups. After the interaction period, community structure of both fish and anemone’s epthelial community structures maintained the interaction signature 2 weeks after fish–anemone pairs’ separation. Furthermore, the interaction signature persistence was observed both in the Physical and Remote Interaction groups, thus suggesting that water-mediated chemical communication between symbiotic partners was strong enough to shift the skin microbiota durably, even after the separation of fish–anemone pairs. Finally, our results suggest that fish–anemone convergent microbiota restructuration was increasingly associated with the parallel recruitment of three Flavobacteriaceae strains closely related to a tyrosinase-producing Cellulophaga tyrosinoxydans. Conclusions Our study shows that bacterial community restructuration, in the acclimation process, does not only rely on direct physical contact. Furthermore, our results challenge, for the first time, the traditional unidirectional chemical camouflage hypothesis, as we argue that convergence of the epithelial microbiota of both partners may play essential roles in establishing mutual acceptance.

scholarly journals Microbiomes of clownfish and their symbiotic host anemone converge before their first physical contact

2020 ◽  
Author(s):  
Émie Audet Gilbert ◽  
François-Étienne Sylvain ◽  
Sidki Bouslama ◽  
Nicolas Derome
Keyword(s):  
Molecular Mimicry ◽  
Water System ◽  
Physical Contact ◽  
Physical Interaction ◽  
Skin Microbiota ◽  
Chemical Camouflage ◽  
Heteractis Magnifica ◽  
Host Anemone ◽  
Remote Interaction ◽  
Interaction Period

Abstract BackgroundOne of the most charismatic, and yet not completely resolved example of mutualistic interaction is the partnership of clownfish and its symbiotic sea anemone. The mechanism explaining this tolerance currently relies on the molecular mimicry of clownfish epithelial mucus, which could serve as camouflage, preventing the anemone's nematocysts' discharge. Resident bacteria are known as key drivers of epithelial mucus chemical signature in vertebrates. A recent study has proposed a restructuration of the skin microbiota in a generalist clown fish when first contacting its symbiotic anemone. We explored a novel hypothesis by testing the effect of remote interaction on epithelial microbiota restructuration in both partners. MethodsWith metataxonomics, we investigated the epithelial microbiota dynamic of 18 pairs of percula clownfish (Amphiprion percula) and their symbiotic anemone Heteractis magnifica in remote interaction, physical interaction and control groups for both partners during a four weeks trial.ResultsPhysical and Remote Interaction groups’ results evidence gradual epithelial microbiota convergence between both partners when fish and anemone were placed in the same water system. This convergence occurred preceding any physical contact between partners, and was maintained during the two-weeks interaction period in both contact groups. After the interaction period, community structure of both fish and anemone’s epthelial community structures maintained the interaction signature two weeks after fish-anemone pairs separation. Furthermore, the interaction signature persistence was observed both in Physical and Remote Interaction groups, thus suggesting that water-mediated chemical communication between symbiotic partners was strong enough to shift the skin microbiota durably, even after the separation of fish-anemone pairs. Finally, our results suggest that fish-anemone convergent microbiota restructuration was increasingly associated with the parallel recruitment of three Flavobacteriaceae strains closely related to a tyrosinase-producing Cellulophaga tyrosinoxydans. ConclusionsOur study shows that bacterial community restructuration, in the acclimation process, does not only rely on direct physical contact. Furthermore, our results challenge, for the first time, the traditional unidirectional chemical camouflage hypothesis, as we argue that convergence of the epithelial microbiota of both partners may play essential roles in establishing mutual acceptance.

scholarly journals Microbiomes of Clownfish and Their Symbiotic Host Anemone Converge Before Their First Physical Contact

2021 ◽  
Author(s):  
Émie Audet-Gilbert ◽  
François-Étienne Sylvain ◽  
Sidki Bouslama ◽  
Nicolas Derome
Keyword(s):  
Molecular Mimicry ◽  
Water System ◽  
Physical Contact ◽  
Physical Interaction ◽  
Skin Microbiota ◽  
Chemical Camouflage ◽  
Heteractis Magnifica ◽  
Host Anemone ◽  
Remote Interaction ◽  
Interaction Period

Abstract BackgroundOne of the most charismatic, and yet not completely resolved example of mutualistic interaction is the partnership of clownfish and its symbiotic sea anemone. The mechanism explaining this tolerance currently relies on the molecular mimicry of clownfish epithelial mucus, which could serve as camouflage, preventing the anemone's nematocysts' discharge. Resident bacteria are known as key drivers of epithelial mucus chemical signature in vertebrates. A recent study has proposed a restructuration of the skin microbiota in a generalist clown fish when first contacting its symbiotic anemone. We explored a novel hypothesis by testing the effect of remote interaction on epithelial microbiota restructuration in both partners. MethodsWith metataxonomics, we investigated the epithelial microbiota dynamic of 18 pairs of percula clownfish (Amphiprion percula) and their symbiotic anemone Heteractis magnifica in remote interaction, physical interaction and control groups for both partners during a four weeks trial.ResultsPhysical and Remote Interaction groups’ results evidence gradual epithelial microbiota convergence between both partners when fish and anemone were placed in the same water system. This convergence occurred preceding any physical contact between partners, and was maintained during the two-weeks interaction period in both contact groups. After the interaction period, community structure of both fish and anemone’s epthelial community structures maintained the interaction signature two weeks after fish-anemone pairs separation. Furthermore, the interaction signature persistence was observed both in Physical and Remote Interaction groups, thus suggesting that water-mediated chemical communication between symbiotic partners was strong enough to shift the skin microbiota durably, even after the separation of fish-anemone pairs. Finally, our results suggest that fish-anemone convergent microbiota restructuration was increasingly associated with the parallel recruitment of three Flavobacteriaceae strains closely related to a tyrosinase-producing Cellulophaga tyrosinoxydans. ConclusionsOur study shows that bacterial community restructuration, in the acclimation process, does not only rely on direct physical contact. Furthermore, our results challenge, for the first time, the traditional unidirectional chemical camouflage hypothesis, as we argue that convergence of the epithelial microbiota of both partners may play essential roles in establishing mutual acceptance.

scholarly journals Microbiomes of clownfish and their symbiotic host anemone converge before their first physical contact

2020 ◽  
Author(s):  
Émie Audet Gilbert ◽  
François-Étienne Sylvain ◽  
Sidki Bouslama ◽  
Nicolas Derome
Keyword(s):  
Molecular Mimicry ◽  
Water System ◽  
Physical Contact ◽  
Physical Interaction ◽  
Skin Microbiota ◽  
Chemical Camouflage ◽  
Heteractis Magnifica ◽  
Host Anemone ◽  
Remote Interaction ◽  
Interaction Period

Abstract BackgroundOne of the most charismatic, and yet not completely resolved example of mutualistic interaction is the partnership of clownfish and its symbiotic sea anemone. The mechanism explaining this tolerance currently relies on the molecular mimicry of clownfish epithelial mucus, which could serve as camouflage, preventing the anemone's nematocysts' discharge. Resident bacteria are known as key drivers of epithelial mucus chemical signature in vertebrates. A recent study has proposed a restructuration of the skin microbiota in a generalist clown fish when first contacting its symbiotic anemone. We explored a novel hypothesis by testing the effect of remote interaction on epithelial microbiota restructuration in both partners. MethodsWith metataxonomics, we investigated the epithelial microbiota dynamic of 18 pairs of percula clownfish (Amphiprion percula) and their symbiotic anemone Heteractis magnifica in remote interaction, physical interaction and control groups for both partners during a four weeks trial.ResultsPhysical and Remote Interaction groups’ results evidence gradual epithelial microbiota convergence between both partners when fish and anemone were placed in the same water system. This convergence occurred preceding any physical contact between partners, and was maintained during the two-weeks interaction period in both contact groups. After the interaction period, community structure of both fish and anemone’s epthelial community structures maintained the interaction signature two weeks after fish-anemone pairs separation. Furthermore, the interaction signature persistence was observed both in Physical and Remote Interaction groups, thus suggesting that water-mediated chemical communication between symbiotic partners was strong enough to shift the skin microbiota durably, even after the separation of fish-anemone pairs. Finally, our results suggest that fish-anemone convergent microbiota restructuration was increasingly associated with the parallel recruitment of three Flavobacteriaceae strains closely related to a tyrosinase-producing Cellulophaga tyrosinoxydans. ConclusionsOur study shows that bacterial community restructuration, in the acclimation process, does not only rely on direct physical contact. Furthermore, our results challenge, for the first time, the traditional unidirectional chemical camouflage hypothesis, as we argue that convergence of the epithelial microbiota of both partners may play essential roles in establishing mutual acceptance.

scholarly journals Microbiomes of Clownfish and Their Symbiotic Host Anemone Converge Before Their First Physical Contact.

2021 ◽  
Author(s):  
Émie Audet-Gilbert ◽  
François-Étienne Sylvain ◽  
Sidki Bouslama ◽  
Nicolas Derome
Keyword(s):  
Molecular Mimicry ◽  
Water System ◽  
Physical Contact ◽  
Physical Interaction ◽  
Skin Microbiota ◽  
Chemical Camouflage ◽  
Heteractis Magnifica ◽  
Host Anemone ◽  
Remote Interaction ◽  
Interaction Period

Abstract BackgroundOne of the most charismatic, and yet not completely resolved example of mutualistic interaction is the partnership of clownfish and its symbiotic sea anemone. The mechanism explaining this tolerance currently relies on the molecular mimicry of clownfish epithelial mucus, which could serve as camouflage, preventing the anemone's nematocysts' discharge. Resident bacteria are known as key drivers of epithelial mucus chemical signature in vertebrates. A recent study has proposed a restructuration of the skin microbiota in a generalist clown fish when first contacting its symbiotic anemone. We explored a novel hypothesis by testing the effect of remote interaction on epithelial microbiota restructuration in both partners. MethodsWith metataxonomics, we investigated the epithelial microbiota dynamic of 18 pairs of percula clownfish (Amphiprion percula) and their symbiotic anemone Heteractis magnifica in remote interaction, physical interaction and control groups for both partners during a four weeks trial.ResultsPhysical and Remote Interaction groups’ results evidence gradual epithelial microbiota convergence between both partners when fish and anemone were placed in the same water system. This convergence occurred preceding any physical contact between partners, and was maintained during the two-weeks interaction period in both contact groups. After the interaction period, community structure of both fish and anemone’s epthelial community structures maintained the interaction signature two weeks after fish-anemone pairs separation. Furthermore, the interaction signature persistence was observed both in Physical and Remote Interaction groups, thus suggesting that water-mediated chemical communication between symbiotic partners was strong enough to shift the skin microbiota durably, even after the separation of fish-anemone pairs. Finally, our results suggest that fish-anemone convergent microbiota restructuration was increasingly associated with the parallel recruitment of three Flavobacteriaceae strains closely related to a tyrosinase-producing Cellulophaga tyrosinoxydans. ConclusionsOur study shows that bacterial community restructuration, in the acclimation process, does not only rely on direct physical contact. Furthermore, our results challenge, for the first time, the traditional unidirectional chemical camouflage hypothesis, as we argue that convergence of the epithelial microbiota of both partners may play essential roles in establishing mutual acceptance.

scholarly journals Microbiomes of clownfish and their symbiotic host anemone converge before their first physical contact.

2020 ◽  
Author(s):  
Émie Audet-Gilbert ◽  
François-Étienne Sylvain ◽  
Sidki Bouslama ◽  
Nicolas Derome
Keyword(s):  
Community Structure ◽  
Molecular Mimicry ◽  
Water System ◽  
Physical Contact ◽  
Physical Interaction ◽  
Skin Microbiota ◽  
Chemical Camouflage ◽  
Host Anemone ◽  
Remote Interaction ◽  
Interaction Period

Abstract Background One of the most charismatic, and yet mostly unexplained example of mutualistic interaction is the partnership of clownfish and its symbiotic sea anemone. The mechanism explaining this tolerance currently relies on the molecular mimicry of clownfish epithelial mucus, which could serve as camouflage, preventing the anemone's nematocysts' discharge. Resident bacteria are known as key drivers of epithelial mucus chemical signature in vertebrates. A recent study has proposed a restructuration of the skin microbiota in a generalist clown fish when first contacting its symbiotic anemone. We explored a novel hypothesis by testing the effect of remote interaction on epithelial microbiota restructuration in both partners. Methods With metataxonomics, we investigated epithelial microbiota dynamics of 18 pairs of percula clownfish (Amphiprion percula) and their symbiotic anemone Heteractis magnifica in remote interaction, physical interaction and control groups for both partners during a four weeks trial.Results Physical and Remote Interaction groups’ results evidence epithelial microbiota convergence between both partners as soon as 15 minutes after fish and anemone have been placed in the same water system. This convergence occurred preceding any physical contact between partners, and was maintained during the two-weeks interaction period in both contact groups. After the interaction period, community structure of test anemones gradually shifted back to the state of their controls, whereas skin community structure of test clownfish maintained the interaction signature two weeks after fish-anemone pairs separation. Furthermore, the interaction signature persistence was observed both in Physical and Remote Interaction group fishes, thus suggesting that water-mediated chemical communication between symbiotic partners was strong enough to shift the skin microbiota durably, even after fish-anemone pairs separation. Finally, our results suggest that fish-anemone convergent microbiota restructuration was increasingly associated with the parallel recruitment of three Flavobacteriaceae strains closely related to a tyrosinase-producing Cellulophaga tyrosinoxydans. Conclusions Our study shows that bacterial community restructuration, in the acclimation process, does not only rely on direct physical contact. Furthermore, our results challenge, for the first time, the traditional unidirectional chemical camouflage hypothesis, as we argue that convergence of the epithelial microbiota of both partners may play essential roles in establishing mutual acceptance.

scholarly journals Mechanisms of Anxiety Reduction in Animal-Assisted Interventions for Adolescents

2020 ◽  
Author(s):  
Megan Kiely Mueller ◽  
Eric C Anderson ◽  
Erin K. King ◽  
Heather L. Urry
Keyword(s):  
Social Interaction ◽  
Social Anxiety ◽  
Empirical Evidence ◽  
Cognitive Performance ◽  
Mechanisms Of Action ◽  
Anxiety Reduction ◽  
Physical Contact ◽  
Physical Interaction ◽  
Autonomic Reactivity ◽  
Therapy Dog

Animal-assisted interventions (AAIs) are increasingly popular as treatments to reduce anxiety. However, there is little empirical evidence testing the mechanisms of action in AAIs, especially among adolescents. We examined whether two possible mechanisms, social interaction and/or physical contact with a therapy dog, might reduce anxiety during a social stressor. To test these mechanisms, we randomly assigned 75 adolescents with low, middle, and high levels of social anxiety to complete a laboratory-based social evaluative stressor in one of three conditions: social interaction with a therapy dog (no physical interaction), social plus physical interaction with a therapy dog, or no interaction with a therapy dog. We found no evidence that the presence of a real dog, with or without the opportunity to touch it, reduced anxiety or autonomic reactivity or improved cognitive performance relative to the presence of a stuffed dog in the control condition, regardless of levels of preexisting social anxiety.

scholarly journals A Novel 3D Model for Visualization and Tracking of Fibroblast-Guided Directional Cancer Cell Migration

Biology ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 328
Author(s):  
Yihe Zhang ◽  
Bingjie Jiang ◽  
Meng Huee Lee
Keyword(s):  
Cell Migration ◽  
Cancer Cells ◽  
Cancer Cell ◽  
Molecular Mechanisms ◽  
Cell Mass ◽  
Physical Contact ◽  
Physical Interaction ◽  
Matrix Remodeling ◽  
Cancer Cell Migration ◽  
Cell Type

Stromal fibroblasts surrounding cancer cells are a major and important constituent of the tumor microenvironment not least because they contain cancer-associated fibroblasts, a unique fibroblastic cell type that promotes tumorigenicity through extracellular matrix remodeling and secretion of soluble factors that stimulate cell differentiation and invasion. Despite much progress made in understanding the molecular mechanisms that underpin fibroblast–tumor cross-talk, relatively little is known about the way the two cell types interact from a physical contact perspective. In this study, we report a novel three-dimensional dumbbell model that would allow the physical interaction between the fibroblasts and cancer cells to be visualized and monitored by microscopy. To achieve the effect, the fibroblasts and cancer cells in 50% Matrigel suspension were seeded as independent droplets in separation from each other. To allow for cell migration and interaction, a narrow passage of Matrigel causeway was constructed in between the droplets, effectively molding the gel into the shape of a dumbbell. Under time-lapse microscopy, we were able to visualize and image the entire process of fibroblast-guided cancer cell migration event, from initial vessel-like structure formation by the fibroblasts to their subsequent invasion across the causeway, attracting and trapping the cancer cells in the process. Upon prolonged culture, the entire population of fibroblasts eventually infiltrated across the passage and condensed into a spheroid-like cell mass, encapsulating the bulk of the cancer cell population within. Suitable for almost every cell type, our model has the potential for a wider application as it can be adapted for use in drug screening and the study of cellular factors involved in cell–cell attraction.

Contact and Physical Interaction

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Neville Hogan
Keyword(s):  
Human Performance ◽  
Force Feedback ◽  
Dynamic Instability ◽  
Null Space ◽  
Variable Stiffness ◽  
Physical Contact ◽  
Annual Review ◽  
Publication Date ◽  
Physical Interaction ◽  
Interactive Dynamics

This article reviews approaches to controlling robots undergoing physical contact and dynamic interaction with objects in the world. Conventional motion control is compared with a hybrid combination of position and force control. Several challenges are reviewed, most importantly the problems of instability: dynamic instability due to coupling, and static instability due to exerting force. Energetically passive interactive dynamics addresses the former; a minimum stiffness proportional to the force exerted addresses the latter. Actuators, which dominate the robot's interactive dynamics, are briefly surveyed, including series elastic, variable-stiffness, and emerging designs. A comparison with human performance is made. A bioinspired approach to controlling interactive dynamics (mechanical impedance or admittance) is reviewed. Robot configuration profoundly modulates apparent inertia, whereas force feedback control has minimal influence. Superimposing first-order mechanical impedances simplifies controlling many degrees of freedom. It manages redundancy while preserving passivity (unlike null-space projection methods) and enables seamless operation into and out of singular configurations. Expected final online publication date for the Annual Review of Control, Robotics, and Autonomous Systems, Volume 5 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Dependency of CLL Cell Survival on Direct Physical Interaction with Bone Marrow Stromal Cells In Vitro Is Largely Outweighed by Secretion of Soluble Factors with Time In Culture

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1365-1365 ◽  
Author(s):  
Iris Gehrke ◽  
Simon Jonas Poll-Wolbeck ◽  
Michael Hallek ◽  
Karl-Anton Kreuzer
Keyword(s):  
Bone Marrow ◽  
Cell Survival ◽  
Stromal Cells ◽  
Bone Marrow Stromal Cells ◽  
Culture Conditions ◽  
Marrow Stromal Cells ◽  
Physical Contact ◽  
Physical Interaction ◽  
Soluble Factors

Abstract Abstract 1365 The major pathophysiology feature of chronic lymphocytic leukemia (CLL) cells is their extended life span due to a pronounced resistance towards apoptotic stimuli in vivo. Despite this, CLL cells die within a few days when isolated from their natural microenvironment and are placed under cell culture conditions. That is why the bone marrow microenvironment has been ascribed an essential role in maintenance of the apoptotic resistance of the CLL cell. Thereby both, the physical interaction between bone marrow stromal cells and CLL cells and the secretion of soluble factors have been described to be essentially involved. We analysed the survival capacity of CLL cells in monoculture and in coculture with the bone marrow-derived stromal cell line HS5 with and without physical separation using transwells for up to 7 days by flow cytometric determination of Annexin-V/PI status. As expected, in vitro CLL cell survival was significantly reduced when physical contact between CLL cells and bone marrow stromal cells was prevented. Interestingly, this was only the case for short term cultivation for up to three days. With time under culture conditions CLL cell survival became less dependent on direct physical contact with the HS5 feederlayer, suggesting the secretion of soluble factors to compensate for the loss of pro-survival signals obtained from direct cell-cell interactions over time. This was further supported by the fact of reduced survival support for CLL cells when HS5 proliferation, hence production and secretion of soluble factors, was prevented by mitomycin treatment or formaldehyde fixation. The use of an expanded human Cytokine Antibody Array (Affymetrix), which analyses the presence of the most common 36 cytokine proteins, might offer information about the composition of soluble factors present in the supernatant which are essential for CLL cell survival in vitro. In conclusion, while direct cell-cell contact between CLL cells and bone marrow stromal cells provides an immediate protection against in vitro apoptosis of CLL cells, the secretion of soluble factors, most likely by both, CLL and bone marrow stormal cells, leads to the creation of an in vitro environment which can to a certain extent compensate for the loss of prosurvival signals obtained by direct physical interactions. Disclosures: No relevant conflicts of interest to declare.

Sign in / Sign up

Export Citation Format

Share Document