makes microbiology easier

Cellular biology

A global offer to cellular infection and response

Thanks to its cellular biology platform, Smaltis offers different study models on eukaryotic cells. 

Context

Understanding the interactions between cells and bacteria is a key point in the fight against infections. Cellular infection models can predict the interactions and behavior of bacteria with eukaryotic cells.
For example, infection models of polarized epithelial cells have been shown to be very effective and predictive of bacterial interactions with the mucosal barrier in vivo.

In addition, cellular models allow other explorations such as the analysis of cytotoxicity induced by compounds or microorganisms.

Smaltis has thus equipped itself with a cell culture laboratory allowing to work on different lines and to propose various services. In partnership with the mAbEXperts group, Smaltis offers a global service related to the study of cellular response.

Our offer

Services and tested products

Various models are already available or are specifically designed to accompany the development of products acting against bacterial infections or to evaluate the cytotoxicity of a compound or a microorganism. These cellular models allow the assessment of the impact of anti-infectious molecules, biomolecules, bacterial strains, bacterial compounds, and phages, on:

– Interactions between pathogenic bacteria or bacterial substances (supernatant, vesicles…) and eukaryotic cells
– The direct response of cells to these compounds or microorganisms

These pre-clinical services allow us to accompany you in your research projects and to provide data on your compounds or bacteria under development, in order to prepare regulatory files and to guide you in the screening of candidates.

Pre-requisites

Different prerequisites are necessary before any manipulation in order to correctly establish the experimental conditions:

  • Determination of the optimal physiological conditions
  • Minimum Inhibitory Concentration (MIC)
  • Lethal Concentration 50 (LC50)
  • Effective Concentration 50 (EC50)
  • Multiplicity of Infection (MoI)

Tools

  • Bacterial adhesion, aggregation and invasion: characterization and quantification
  • Cytotoxicity: quantification of cell death by measuring the release of lactate dehydrogenase (LDH) into the medium, by assessing MTT cleavage, or by determining hemolytic activity (red blood cells lysis)
  • Genomic response: quantification of specific gene expression to identify signaling pathways (e.g. inflammation, autophagy, apoptosis) by RT-qPCR
  • Proteomic response: measurement of protein secretion (ELISA, ELIspot, Western Blot) in the culture medium after infection (e.g. cytokines/inflammatory mediators)
  • Global cell response: migration (factor mediated), proliferation (evaluation of stimulation and growth by counting)
  • Immunostaining with specific antibodies and visualization of fluorescence
  • Bacterial enumeration
  • ADCC: antibody-dependent cell-mediated cytotoxicity
  • Stimulation of cytokine production by cells
  • Phagocytosis of cells and bacteria
  • ADCP: antibody-dependent phagocytosis
  • Multiparametric analysis using Luminex™ technology

Cell lines

Sourcing of bacteria

  • Intestinal cells
    Caco2, T84, HT29
  • Lung cells
    A549 et NCI-H820
  • Macrophages
    Murine macrophages J774A.1, THP-1 Monocytes
  • Osteoblasts
    MG63
  • Skin cells
    Keratinocytes, Melanocytes…
  • Other on request
  • Tumor library: access to tumor cell lines or tissues from patients
  • Reference strains
    Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, Enterobacter spp….
  • Clinical strains
    Access to more than 40 000 strains isolated from different pathologies
  • Characterized mutant strains
    Example: targeted mechanisms of resistance
    Already available or to be created according to the project
  • Patient’s samplings
    Patient’s samplings containing bacterial strains

Examples of achievements

Immunostaining characterization of adhesion/invasion properties of E. coli strains on an intestinal cell line

Assessment of the effect of infant food compounds on the adhesion of E. coli strains to intestinal cells

Assessment of adhesion/invasion power of environmental strains (Pantoea sp, Arthobacter sp, Bacillus subtilis)

Characterization and assessment of cytotoxicity of mutants derived from P. aeruginosa strain PAO1 on lung lines and macrophages

Assessment of the effect of compounds and strains on extracellular and intracellular bacterial clearance

Assessment of the efficacy of antibacterial compounds on S. aureus strains phagocyted by macrophages

Determination of bacteriophages-induced cytotoxicity on osteoblasts line