FOCUS - Immunology

Various T helper cell sub-populations in the control of adaptive immune responses – implications for pharmacodynamic studies on immuno-modulatory compounds

Perlik — Tue, 10 Aug 2010 16:25:53 +0000

T lymphocytes mature into CD4- or CD8-expressing single positive cells in the thymus from where they become “peripheral T lymphocytes” which populate the secondary lymphoid organs. Upon interaction with antigen-presenting cells, peripheral T lymphocytes become activated, proliferate and expand to differentiate into effector and memory cells.

Until some years ago two functionally different CD4+ T helper (Th) cell types were known, i.e. “Th1 cells” which are induced by the action of IFN-gamma and IL-12 to protect against specific intracellular pathogens, and “Th2 cells” which are induced by IL-4 to encounter parasitic infections and also to participate in allergic reactions.
Additional CD4+ Th subtypes have been described meanwhile.

First the “Th17 effector T cell”, which produces IL-17 and IL-6 and which is generated by the action of IL-23. Th17 cells function to clear a range of pathogens distinct from Th1 and under pathologiocal conditions they are involved in autoimmune responses. The latter has sparked general interest for these cells as targets for immuno-modulatory and anti-inflammatory therapies.

“Treg cells” (CD4+, CD25+, FoxP3+) represent another variant of CD4+ effector T-cells with a pivotal role in the regulation of immune responses.

FOCUS Immunology provides state-of-the-art scientific support and services to study these cell types under GLP conditions. If you are interested in learning more about FOCUS Immunology’s experience and offers or if you want to discuss your specific experimental needs, please feel free to contact:

Dr. Eddy Bruyns, Head of FOCUS Immunology Laboratory via e-mail eddy.bruyns@focus-cdd.com or via telephone +49 6221 64935124.

Bettelli et al Nat Immunol 2007 8:345-350
Shevach Immunol Rev 2006 212: 60-73
Murphy Nat Rev Immunol 2002 2: 933-944

“Multiple cytokine secreting cells”: central players in pharmaco-dynamics of immuno-modulatory therapies?

Perlik — Tue, 10 Aug 2010 16:09:17 +0000

In a workshop hosted by the European Medicine Agency the possible role of in vitro cytokine release assays for prediction of unwanted side effects of novel (immuno-) therapeutics has been discussed. With respect to the latter the “cytokine release syndrome” and “cytokine storm” are severe and sometimes fatal adverse clinico-pathological events for which predictive assay systems are urgently needed.

In the workshop the central role of so-called “multiple cytokine secreting cells” in the pharmaco-dynamics of immuno-modulatory compounds and associated adverse events was pointed out.

As the name implies, these cells are characterized by the production of several cytokines in any single cell and thus contrast cells in which only one or two cytokines may be detected. In other words: “Multiple Cytokine Secretion” is a functional characteristic of a given cell and pretty much every T cell may become such a multiple cytokine secreting cell upon activation. Multiple cytokine secretion is a temporary state, only as long as the cell is being activated.

Physiological stimulation of T cells to multiple cytokine secretion is required for host defense and tissue remodeling. However, aberrant or un-intentional stimulation under pathological conditions or by (over-dosing of) immuno-modulatory compounds may result in severe pathologies, such as the above-mentioned “Cytokine Release Syndrome“.

The analysis of multiple cytokine secreting cells requires sophisticated multi-parameter assays, like multiplex immunological assays for measuring cytokine profiles in cellular secretions under various stimulation conditions. Ultimately, it requires multi-color intracellular cytokine staining by flow cytometry, which allows multiple cytokine determinations at the single level.

FOCUS Immunology is experienced in providing state-of-the-science analyses for multiple cytokine secreting cells under GLP conditions. If you are interested in learning more about FOCUS Immunology’s experience and offers or if you want to discuss your specific experimental needs, please feel free to contact
Dr. Eddy Bruyns, Head of FOCUS Immunology Laboratory via e-mail eddy.bruyns@focus-cdd.com or via telephone +49 6221 64935124.

EMEA workshop: “In vitro cytokine release assays to predict Cytokine Release Syndrome: the current-state-of-the science”

Presentation: Specific challenges in human pharmacology trials with biologicals

Perlik — Fri, 16 Jul 2010 15:13:47 +0000

In his presentation Dr. Greb, president and CEO of Focus Clinical Drug Development GmbH (Neuss, Germany), summarizes pertinent issues of early phase development of biologicals.

He points out that careful analysis of the molecular situation is required and that the relevant target structures and species need to be chosen in preclinical evaluation of the compounds activity.

You may wish to download Dr. Greb’s presentation for your personal use. To order a complimentary copy of Dr. Greb’s presentationon specific challenges in human pharmacology trials with biologicals enter your email address below and press the submit button:
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A detailed complimentary copy of Dr. Greb’s presentation can be ordered by entering your email address below and pressing the submit button:
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“FOCUS Immunology Laboratories Heidelberg” offer testing of biomarkers for immune cell functions tailored to the specific requirements of a given clinical trial.

For further information please contact Dr. Eddy Bruyns at eddy.bruyns@focus-cdd.com.

Elucidating the immuno-modulatory activities of statins (simvastatin)

admin — Fri, 02 Jul 2010 15:41:14 +0000

Zhang and colleagues explored the immunomodulatory activity of the cholesterol-lowering agent simvastatin. Their pharmaco-dynamic studies indicated that the immuno-modulatory activity of statins may involve two basic mechanisms. First, it may involve an increase in SOCS-3 and SOCS -7, i.e. members of the molecular family of “Suppressors of Cytokine Secretion”. And second, it may involve the inhibition of Interleukin-17 (IL-17), a central pro-inflammatory mediator.

The members of the SOCS family of molecules are important negative feedback regulators in adaptive and innate immune responses, while IL-17 producing CD4+ cells, the so-called “Th17 cells”, play a central role in the development of autoimmune diseases.

From their findings the authors conclude as follows: “Based on the described immunomodulatory mechanisms, good safety profile and oral biovailabalility, statins represent a promising therapeutic approach for multiple sclerosis and other chronic inflammatory diseases.”

Along the lines of this study by Zhang and colleagues, FOCUS Immunology is prepared to provide state-of-the-art services for pharmacodynamic (PD) analyses of immuno-modulatory compounds under GLP conditions.

If you are interested in learning more or in discussing your specific experimental needs, please feel free to contact Dr. Eddy Bruyns, Head of FOCUS Immunology Laboratory via e-mail eddy.bruyns@focus-cdd.com or via telephone +49 6221 64935124.

Source
Zhang et al.
Simvastatin Inhibits IL-17 Secretion by Targeting Multiple IL-17-Regulatory Cytokines and by Inhibiting the Expression of IL-17 Transcription Factor RORC in CD4+ Lymphocytes
The Journal of Immunology 2008; 180; 6988-6996

SOCS proteins (“Suppressors of Cytokine Signaling”): regulators for innate and adaptive immune responses with relevance for the pharmacodynamics of immuno-modulatory compounds

admin — Fri, 02 Jul 2010 15:16:00 +0000

Hyperactivation of the immune system can lead to tissue destruction and auto-immunity. Therefore, the amplitude and duration of immune responses after antigenic and cytokine signaling are regulated in a feedback manner.

So-called “Suppressors of Cytokine Signaling (SOCS)” are important molecular players in this negative feedback regulation. 7 members of the SOCS molecular family have been described so-far. The SOCS family members 1 and 3 are of particular importance, since they are involved in adaptive and innate immune responses.

SOCS-1 and -3 are induced by LPS stimulation via the Toll-like Receptor-4 (TLR-4). While SOCS-1 directly targets the downstream signaling molecules of TLR4, SOCS-3 regulates the secondary effects of many LPS-induced cytokines. E.g. IL-1R signalling pathways are negatively regulated by SOCS-3.

In adaptive immune responses SOCS-1 and -3 play a role in the regulation of T cell activation, proliferation and diferentiation.
Recently, SOCS molecules were found to be central elements in the pharmacodynamics of the immuno-modulatory compound simvastatin and probiotic lactobacilli.

FOCUS Immunology is prepared to provide state-of-the-art services for pharmacodynamic (PD) studies for immunomodulatory compounds under GLP conditions. This includes studies on the regulation of intra- and extracellular mediators of inflammationand immunity.

If you are interested in learning more about FOCUS Immunology’s experience and offers or if you want to discuss your specific experimental needs, please feel free to contact Dr. Eddy Bruyns, Head of FOCUS Immunology Laboratory via e-mail eddy.bruyns@focus-cdd.com or via telephone +49 6221 64935124.

Source
Dimitriou et al.
Putting out the fire: coordinated suppression of the innate and adaptive immune systems by SOCS1 and SOCS3 proteins
Immunological reviews 2008, Vol. 224: 265-283

More information on SOCS1: Wikipedia on SOCS1
More information on SOCS3: Wikipedia on SOCS3

Regulation of Suppressors of Cytokine Signaling (SOCS) expression as an anti-inflammatory mechanism of probiotics

admin — Fri, 02 Jul 2010 14:41:17 +0000

Suppressors of Cytokine Signaling (SOCS) are a group of proteins that play an important role in attenuating immune responses. These molecules may thus be important players in the pharmacodynamics (PD) of immuno-modulatory therapies.

In a recent publication Lee and colleagues explored whether probiotics induced anti-inflammatory properties through induction of SOCS.

Helicobacter pylori (H. pylori) or lipopolysaccharides derived thereof were found to increase the expression of pro-inflammatory cytokines in a human gastric cell line. Pre-treatment of the cells with probiotic bacteria of the Lactobacillus group reduced the H.Pylori-induced expression of these cytokines.

When the underlying molecular mechanisms were explored in more detail, the administration of probiotics was found to increase the expression of SOCS-2 and SOCS-3.

The authors conclude that the “Anti-inflammatory signals of SOCS … might be a key anti-inflammatory mechanism of probiotics …”

FOCUS Immunology is prepared to provide state-of-the-art servcies for pharmacodynamic (PD) studies for immunomodulatory compounds under GLP conditions.

Source
Jeong Sang Lee et al.
Anti-inflammatory actions of probiotics through activating suppressor of cytokine signaling (SOCS) expression and signaling in Helicobacter pylori infection: A novel mechanism
Journal of Gastroenterology and Hepatology 25 (2010) 194-202

In vitro maturation of Dendritic Cells and Macrophages

admin — Fri, 14 May 2010 08:36:09 +0000

The myeloid/monocytic lineage of haematopoietic cells has an enormous functional and phenotypic plasticity.

Monocytes contained in circulating blood are an eminent example for this. After having entered peripheral tissues monocytes develop into tissue macrophages which play various roles under physiological and pathological conditions: removal of pathogens, antigen uptake and presentation, resolution of wound healing and propagation of chronic inflammations.

Moreover, cultured peripheral blood monocytes can be developed into professional antigen-presenting cells, so-called Dendritic Cells, which are used in tumor clinical vaccination protocols.

FOCUS Immunology has implemented state-of-the-art protocols for the in vitro maturation of functional active cell populations from human peripheral blood monocytes. In vitro generated cell populations, like Dendritic Cells or Macrophages are particularly suitable to explore specific aspects of immuno-modulatory and immuno-suppresssive compounds and treatment strategies.

For further information please contact us at immunology@focus-cdd.com or contact directly our Head of FOCUS Immunology Dr. Eddy Bruyns at eddy.bruyns@focus-cdd.com.

Immune System Testing Packages for Development of Biologicals

admin — Wed, 05 May 2010 07:00:17 +0000

In a recent issue of “Nature Biotechnology” (Volume 28, Nr. 4, April 2010) Cormac Sheridan featured the status of biologicals development in 2009. From this and the associated specific articles on monoclonal antibody development it is obvious that biologicals are gaining more and more importance for sustaining the new products pipelines of pharmaceutical companies.

The development of new biologicals is associated with specific challenges. Some relate to the immunogenic and immune-modulatory properties of biologicals. Some keywords are „immunogenicity testing”, “cytokine storm”, “species-specificity of ligand-receptor interactions and down-stream signaling”.

In view of these challenges FOCUS has developed specific testing packages with an emphasis on immuno-modulatory activities of novel drug candidates.

The following testing packages have recently been defined:

Specific immune system package
Innate immune system package
Immune activity screening package for novel and established compounds
Cytokine modulation package for immuno-modulators, esp. immuno-suppressive compounds
Immuno-stimulation package for immune-modulators, vaccines and oncology drugs
Biologicals testing package, esp. for new biological entities (NBEs)

A comprehensive summary can be found in the white paper to be downloaded here.

Source: Cormac Sheridan, „Fresh from the biology pipeline-2009“ Nature Biotechnology Volume 28 Number 4 April 2010

T lymphocytes (T cells): measuring phenotype, activity and function

admin — Sat, 10 Apr 2010 12:53:13 +0000

T lymphocytes (T cells) play a central role in the initiation and propagation of physiological and pathological immune responses. To exert their functions, resting T cells are activated, whereby the activation signals and pathways can be manifold and the resulting cellular functions are diverse.

Modern cell biological techniques allow to distinctively address the different activation pathways by specific stimulators and inhibitors, be it by specific antibodies against cell surface receptors (e.g. anti-CD3, or anti-CD28) or be it by chemical reagents (e.g. phorbol myristate acetate or ionomycin).

These sophisticated stimulation protocols can then be combined with appropriate analytical technologies to assess the phenotype and function of the activated cell populations, like expression of cell surface activation markers, secretion of cytokines, or proliferation.
FOCUS Immunology operates these technologies and tailors their use to the specific needs of a study protocol.

To learn more about FOCUS Immunology’s expertise and service offer in T cell biology contact us at immunology@focus-cdd.com or contact directly our Head of FOCUS Immunology Dr. Eddy Bruyns at eddy.bruyns@focus-cdd.com.

FOCUS Immunology laboratory is part of the Clinical Research Organisation (CRO) FOCUS-CDD GmbH. FOCUS Immunology provides immunological biomarker services under GLP and non-GLP conditions for the development of novel medicines.

Multicolor flow cytometry for immunological biomarker determination on a single cell level

admin — Tue, 23 Mar 2010 15:00:49 +0000

Modern flow cytometric methods allow the simultaneous detection of more than one fluorescent dye, this is termed “Multicolor flow cytometry”.

Thus, multicolor flow cytometry is a technology platform to gather detailed information on specific cells within a mixed population or on different parameters at the single cell level. This is especially relevant to maximize data generation from small or limited samples.

FOCUS Biomarker offers Multicolor Flow Cytometry to analyse immune cell parameters in clinical trials under GLP conditions. Together with our expertise in standardized cell sample generation and transportation as well as GLP-compliant assay development we offer this interesting technology for biomarker determination. This will enhance the assessment of PD aspects in early and late clinical trials with immuno-modulatory or anti-inflammatory drugs.