Water-Based Synthesis of Copper Chalcogenide Structures and Their Photodynamic Immunomodulatory Activities on Mammalian Macrophages

Generation of novel and versatile immunomodulatory agents that could suppress excessive inflammation has been crucial to fight against chronic inflammatory and autoimmune disorders. Immunomodulatory agents regulate the function of immune system cells to manage their activities. Current therapy regimens for the inflammatory and autoimmune disorders rely on immunomodulatory drug molecules but they are also associated with unwanted and severe side effects. In order to prevent the side effects associated with drug molecules, the field should generate novel immunomodulatory drug candidates and further test them. Moreover, the generation of photodynamic immunomodulatory molecules would also decrease possible side effects. Photodynamic activation enables specific and localized activation of the active ingredients upon exposure to a certain wavelength of light. In our study, we generated copper-based chalcogenide structures in gel and nanoparticle form by using a water-based method so that they are more biocompatible.After their chemical characterization, they were tested on mammalian macrophages in vitro. Our results suggest that these molecules were anti-inflammatory in dark conditions and their anti-inflammatory potentials significantly increased upon xenon light treatment. We are presenting novel photodynamic immunomodulatory agents that can be used to suppress excessive inflammation in disease conditions that have been associated with excessive inflammation.

Recent advances in subphthalocyanines and related subporphyrinoids

Subporphyrinoids constitute a class of extremely versatile and attractive compounds. Herein, a comprehensive review of the most recent advances in the fundamentals and applications of these cone-shaped aromatic macrocycles is presented.

Immunoactive photosensitizers had photodynamic immunostimulatory and immunomodulatory effects on mammalian macrophages

Photodynamic compounds have great potential in biological applications. Their controlled and localized activation with specific wavelength of light provides opportunities to potentially evade the side effects of today's cancer therapies. Biologically compatible photosensitizers can be used in therapy against cancer, infections as well as inflammatory and immune disorders. In this study, we examined chlorophyll derivatives for anti-microbial, immunostimulatory and immunomodulatory activities. Under dark conditions, these chlorophyll derivatives had strong anti-microbial activities on gram positive S.aureus and gram negative E.coli. Photo activation of the chlorophyll derivatives did not alter their anti-microbial activities on gram negative or gram positive bacteria. In order to examine how these anti-microbial chlorophyll derivatives might effect immune reaction of macrophages, they were tested on mammalian macrophages. They had immunostimulatory activities on them in the dark conditions since they led to increased TNF and IL6 cytokine production even in the absence of stimulants lipopolysaccharide (LPS) and lipoteichoic acid (LTA). Photo-activation of the compounds led to decrease in pro-inflammatory cytokines, TNF and IL6, production by LPS or LTA activated macrophages. Therefore, these molecules can be used to regulate the immune response in the patients with bacterial infection while leading to death of bacteria. Light induced activation of the compounds could enable localized and controlled activation of their anti-inflammatory effects.

Photo induced anti-inflammatory activities of a Thiophene substituted subphthalocyanine derivative

Materials that possess photo induced biological activities present opportunities for more localized, targeted and efficient treatment options that may also reduce side effects. There have been studies supporting photo induced effects of photosensitizers as anti-cancer, anti-inflammatory and anti-microbial agents. In this study, we tested photo activated anti-inflammatory effects of a Thiophene substituted subphthalocyanine (SubPc) derivative. Thiophene and its derivatives are well known for their anti-inflammatory and anti-microbial effects. There are unwanted side effects associated with Thiophene derivatives. By substituting this biologically active molecule to SubPc structure we acquired control over its activation. Upon light treatment this derivative exerted anti-inflammatory activity on the mammalian macrophages in vitro based on the substantial decrease in extracellular inflammatory cytokine levels. Our results suggest that Thiophene substituted SubPc derivative has photo induced anti-inflammatory activities. This material can be used for the treatment of patients suffering from chronic inflammation that are not associated with a bacterial burden such as autoimmune diseases and inflammatory or allergic reactions.

Ruthenium Bipyridyl Dithiocyanate Complex Exerted Adjuvant Activity on the Activated Mammalian Macrophages in vitro

A cell's function can be regulated through its mechanism, and there has been a growing body of literature on how immune cells' metabolism shapes its overall immune response. Manipulation of the cells metabolic activity through a biocompatible material would present new venues to the field of medicine. These agents are known as immunomodulatory and immunostimulatory reagents. They can either stimulate the immune response in a disease case where the immune response is lacking the strength or they can determine the nature and strength of the immune response as an immunomodulator according to our needs to cope with certain disorders. In our recent studies, we have been examining different kinds of materials on the macrophages in order to delineate their immunostimulatory or immunomodulatory potentials. Ruthenium-based materials have gathered our attention due to their ability to get involved into the electron mobility processes in the solar cells. In line with our expectations, probably by interfering the electron transport processes of the macrophages, ruthenium bipyridyl dithiocyanate complex had a stark immunomodulatory function on the LPS-activated mammalian macrophages in vitro. Our results support that it can be utilized as an adjuvant in the new generation vaccines.

Differential Immunomodulatory Activities of Schiff Base Complexes Depending on their Metal Conjugation

Immunomodulatory compounds have become crucial with advances in immunotherapy. Using our own immune system cells, we can direct the immune cell function and develop desired response against a certain threat. Immunotherapy applications have been suggested against tumors, autoimmune disorders, and infectious diseases. Vaccination can be considered as one of the best known example of immunotherapy. Infectious agent's signature molecular structures are introduced to the immune cells together with the adjuvants that further activate the immune cells to mount a proper immune response and memory. Immunotherapy and vaccine formulations are in constant need of a library of immunomodulatory reagents that can be applied depending on the target. In order to expand the number of immunomodulatory reagents that can find medicinal applications, our group has been testing unique chemical structures on the immune system cells, especially macrophages. Schiff base complexes are known for their anti-inflammatory and antimicrobial activities. In this study, we used previously characterized Schiff base complexes with different metal conjugations. These molecules had differential immunostimulatory and immunomodulatory potentials on macrophages in vitro depending on the type of the conjugated metal. After light exposure, these complexes changed their characteristics and became powerful anti-inflammatory complexes. Due to their possible antimicrobial potentials, we also tested their activities against gram negative and gram positive bacteria. All of the complexes exerted antimicrobial activities which were not light responsive. Here, we present Schiff base complexes with differential immunostimulatory and immunomodulatory activities that can also efficiently eliminate gram positive and gram negative bacteria. Upon photo activation, they block the production of inflammatory TNFα cytokine. Therefore, together with the light, they can be used to treat bacterial infections associated with damaging inflammation. Graphical Abstract.

Differential effects of aminochlorin derivatives on the phagocytic and inflammatory potentials of mammalian macrophages

Chlorin derivatives have been known for their biological activities. Especially due to their advanced electron transfer capacity they have been used as photodynamic therapy agent both at clinical and laboratory scales. Photodynamic therapy (PDT) against cancer or an infectious disease aims the development of less side effect on the patient since the activation of the inert drug molecule will start only after the light treatment. In order to increase our library of photodynamic therapy agents, we generated a set of chlorin derivatives and tested their PDT potential on the immune system cells; macrophages. Macrophages are known for their primary role as an inflammatory cell type that have been found in the inflamed tissues of the patients with autoimmune and inflammatory disorders as well as in the tumor environment as tumor associated macrophages. Our derivatives had anti-inflammatory PDT potential in the presence of a danger mimic but they lacked immunostimulatory effect. Moreover, these cells' ability to eliminate an infectious agent or present the danger molecules to the other immune cells were tested by phagocytosis assay in the presence of our compounds. Chlorin derivatives were able to differentially regulate the phagocytic activity of the mammalian macrophages.

Novel Copper Bearing Schiff Bases with Photodynamic Anti-Inflammatory and Anti-Microbial Activities

Schiff bases and their copper complexes have been previously studied for their anti-inflammatory, anti-tumor as well as anti-microbial activities. Schiff bases can be derivatized to gain photoluminiscence capacity. This property of the schiff bases enables the transfer of the electrons upon absorption of the light at a specific wavelength. In this study, we exploited this attribute of novel copper bearing schiff bases and tested their photodynamic biological activities. These compounds exerted photodynamic anti-inflammatory activities on the in vitro activated mammalian macrophages. Compared with salicylic acid control groups, these novel schiff bases had stronger activity which became more prominent with photo-induction. Moreover, they also had anti-microbial activity on gram negative bacteria E.coli and gram positive bacteria S.aureus.This anti-microbial activity was stronger than that of Neomycin on both bacterial strains. Our results suggest their potential use as anti-inflammatory and anti-microbial agents both in the dark as well as after photo-induction.