Barrier function is the natural role of the skin. The lipid matrix present in the outermost layer of the skin, the stratum corneum is important for this function.

It is the aim of this project to better understand how the physical properties of lipids influences the structure and overall barrier function of the skin.

This thesis advances our understanding of lipid uptake, a vital first step in lipid metabolism, by developing innovative click chemistry-based tools to study how immune cells internalize lipids.

This paper describes two synthetic lipid models designed to replace human stratum corneum (SC) in studies of the impact of volatile organic chemicals on the molecular organization of the skin barrier lipids.

This doctoral thesis is an effort to understand how lipid phase-separation induced by diacylglycerol analogues in lipid-based nanoparticles affects their in vivo behavior, leading to specific nanoparticle-protein communications and selective cell targeting.

Diacylglycerol lipases (DAGLα and DAGLβ) convert diacylglycerol to the endocannabinoid 2-arachidonoylglycerol. Our understanding of DAGL function has been hindered by a lack of chemical probes that can perturb these enzymes in vivo.

Lipid signaling is an essential biological event/process in a plethora of pathophysiological conditions. The underlying idea of this thesis is that many of the roles and the complex interplay of the individual signaling lipids in inflammatory processes and related conditions in health and disease is…

Dit proefschrift beschrijft een collectie aan alternatieve strategieën voor het begrijpen, ontwerpen en toepassen van lipide nanosystemen, waarin de rol van de bio-nano interacties centraal staan. In het bijzonder wordt gekeken naar de interactie van RNA-lipide nanosystemen, bekend van de toepassing…

Ceramides (CERs), cholesterol, and free fatty acids (FFAs) are the main lipid classes in human stratum corneum (SC, outermost skin layer), but no studies report on the detailed analysis of these classes in a single platform.

OBJECTIVES: To determine whether the lipid/protein ratio and the total dry SC mass per surface area are related with the skin barrier function of controls and AE patients.

Microscopic insight on lipid-based nanomedicine in vivo remains limited to the perception of the knowledge that could be obtained: if we interpret only what we see, then we only believe to know. Although believing to know encapsulates an undefined amount of uncertainty in the exploration of lipid-based…

Our research aims to develop drugs that boost the host immune response to better defend us against mycobacteria.

Promotor: J.W.M. Frenken, Co-Promotor: R. Felici

Promotor: P.D. Grünwald

BACKGROUND: Explant human skin equivalents (Ex-HSEs) can be generated by placing a 4mm skin biopsy onto a dermal equivalent. The keratinocytes migrate from the biopsy onto the dermal equivalent, differentiate and form the epidermis of 1(st) generation Ex-HSEs. This is especially suitable for the expansion…

The outermost layer of the skin, the stratum corneum (SC), is responsible for the skin barrier function, protecting the body from pathogens, chemicals and other unwanted substances from the external environment. The SC lipid matrix provides the only continuous pathway through the SC and is considered…

Chris Jacobs, former PhD-student of the IBL, received the national “Dissertation Award” for best PhD thesis of the year on insects. The award was handed out last Friday, the 18th of December, by Professor Matty Berg, president of the Dutch Entomological Society.

Promotor: J. A. Bouwstra

The stratum corneum is the outermost skin layer and consists of dead cells embedded in a lipid matrix.

In the studies described in this study, we introduce a novel ex vivo human skin barrier repair model. To develop this, we removed the upper layer of the skin, the stratum corneum (SC) by a reproducible cyanoacrylate stripping technique.

Christopher Berg Smiet, who defended his thesis at LION with Dirk Bouwmeester, won the Christiaan Huygens prize for his thesis '‘Knots in Plasma’. On 7 October, he received a certificate, a bronze statuette and ten thousand euros.

People with relatively high levels of lipids in their blood are less likely to develop allergic conditions such as eczema and asthma. These lipids cause genes that play a key role in allergic reactions to be less active. Researchers from the Leiden University Medical Center (LUMC) have published an…

Have you ever seen your friend smiling, and suddenly you started grinning too? PhD student Chris Riddell is researching how and why we copy body language. As a new Face of Science, he will take us along on his research journey for the coming year.

As part of the GTGC Lunch Seminars, Chris Wensink and Midas van Dijk presented their book 'Regionalizing Eurasia'. The COVID-19 pandemic restricted travel and placed free trade under scrutiny. Then, the war in Ukraine triggered unprecedented economic sanctions and severing of trade ties. By contrast,…

Anionic particles play an important role in biological systems where they fulfil many essential functions for cells.

The research described in this thesis shows that hypercholesterolemia, a well-established risk factor for atherosclerosis, can impact skin lipid pool and barrier function already at young age. In the field of atherosclerosis, we showed that the small peptide Lyp-1 can be used as a targeting molecule…

Nanodiscs are small, disc-shaped structures designed to mimic biological cell membranes, composed of a lipid bilayer stabilized by scaffold proteins. Membrane proteins play crucial roles in essential processes such as nutrient and waste transport, molecular recognition, and cell signalling, making them…

During the HALON hacking competition, 28 teams had one goal: to find as many vulnerabilities as possible in the systems of Dutch higher education institutions. Research software engineer Chris Handy participated on his own and ended up in second place in the category ‘Vulnerabilities found at the highest…

Promotores: R. Tijdeman, K.J. Batenburg

Current research at the Skin Barrier and Vaccination group.

A memorable farewell symposium and a royal distinction: Professor Joke Bouwstra could not have completed her career at Leiden with more pleasure. On Friday, 14 June, she received a Royal Honor from Leiden Mayor Peter van der Velden, who appointed Bouwstra as a Knight in the Order of the Dutch Lion for…

Tuberculosis is a major global health problem caused by the Mycobacterium tuberculosis complex, claiming more than a million lives annually.

This thesis introduces the concept of

Promotor: A. Kros, Co-promotor: R.R.C.L. Olsthoorn

Cholesterol influences many pathways, including serving as precursor for adrenal steroidogenesis. Imbalance of cholesterol levels has been implicated in several diseases including cardiovascular diseases and its underlying pathology, atherosclerosis.

Focus in skin research

For the first time researchers have succeeded in placing a layer of graphene on top of a stable fatty lipid monolayer. Surrounded by a protective shell of lipids, graphene could enter the body and function as a versatile sensor. The results are the first step towards such a shell, and have been published…

Heart failure is a major health care problem with high mortality.

The PID-directed shift in PIN polarity has been broadly accepted as one of the essential mechanisms for the regulation of auxin transport polarity.

Promotor: A. Kros

Preterm birth is a major contributor to neonatal morbidity and mortality and is associated with both acute complications and long-term health consequences.

What does life look like after International Studies? For Chris Colijn who graduated in 2018, it involves working on his master’s in Russian and Eurasian Studies, in combination with a bustling traineeship for “Raam of Rusland”, a think tank, focusing on Russian and Ukrainian politics, economy and culture.…

The genetic information of all living organisms is contained in their DNA. Cells modify the degree of DNA compaction by epigenetics, which largely determines what genes are read out and which genes are transcriptionally silent.

The Skin Barrier and Vaccination group is led by Prof. Joke Bouwstra. One of the key functions of the skin is its barrier function, which is located in the uppermost layer of the skin, the stratum corneum. The stratum corneum consists of enucleated dead cells (corneocytes) embedded in a lipid matrix.…

Atopic eczema is a skin disease with increasing incidence currently affecting 25% of the paediatric population. In atopic eczema the skin barrier function is reduced. This barrier is formed by the outermost layer of the skin called the stratum corneum (SC). The SC consists of terminally differentiated…