
1. Pathophysiology of mast cells in mastocytosis and in neuroimmunoendocrine disorders. Mast cells are
known for their involvement in allergic reactions, but we were the first to show that they are also necessary
to inititate inflammation, thus participating in inflammatory diseases that worsen by stress, such as autism,
cancer, chronic fatigue syndrome, interstitial cystitis, migraine headaches, psoriasis and multiple sclerosis.
We have developed in vivo and in vitro models for these diseases and we are studying neurohormonal
activation of mast cells. The only plausible way to explain how mast cells can participate in so many diverse
processes is their ability to secrete distinct chemicals relative for different pathophysiological settings (see
below).
2. Molecular events involved in mast cell stimulus-secretion coupling, especially with their ability to release
mediators selectively without degranulation. Mast cells are typically activated by immunoglobulin E and
antigen, a process that leads to an explosive release of over 20 biologically active molecules (some of which
are presorted in some 500 secretory grqnules, wile others are synthesized during activation) through a
process called degranulation or exocytosis. However, we were the first to show that mast cells can also
respond to non-allergic triggers and release mediators selectively, without degranulation. We specifically
reported that the inflammatory cytokine IL-1 can induce selective release of the also inflammatory cytokine
IL-6, that the stress hormone corticotropin-releasing hormone (CRH) can induce selective release of vascular
endothelial growth factor (VEGF), and IL-33 augments substance P-induced VEGF release. We are
currently studying the regulation of CRH receptor expression and function on human cultured mast cells and
the effects of their respective activation on allergic stimulation.
3. Mast cells have the ability to superstimulate activated T cvells; mofeover, the mast cell mediators IL-6 and
TGFbeta participate in the maturation of Th17 cells, which are increasingly imlplicated in autoimmune
diseases such as multiple sclerosis and psoriasis. Par of this process requires cell-to-cell contact, but also
TNF secretion. We are investigating how IL-33 and SP (see above) could drive mast cells to participate in
Th1-type of diseases and how such interactions may be interrupted for therapeutic purposes.
4. Regulation of mast cell secretion by the mitochondrial uncoupling protein 2 (UCP2) and mitochondrial
dynamics. We showed for the first time that there is an inverse relationship between UCP2 expression and
mast cell secretion. We also showed for the firtst time that mast cell degranulation, but not selective release
of tumor necrosis factor (TNF), is associated with mitochondrial fission and relocation from perinuclear
localization to cell-widespread distribution.
5. Antisecretory and antiproliferative function of the 78 kD mast cell phosphoprotein. We sequenced this
protein and showed that, in its phosphorylated state, it inhibits mast cell secretion and tumor growth. We are
investigating the regulation of its expression, identification of the phosphorylated sites and molecules that
could increase and sustain the phosphorylated state of this protein.
6. Anti-allergic and anti-inflammatory actions of some natural polyphenolic flavonoids. We are investigating
the mechanism of action of the select flavnoids luteolin and quercetin, their formulation in ways that
increases their absorption, as well as their blood concentrations in order to achieve maximal effective levels.
Such compounds could serve as anti-allergic, anti-inflammatory and anticancer drugs.
7. Role of neonatal mast cell activation in the pathogenesis of autism. We reported that the prevalence of autism
is ten times higher (1/10 children) in patients with mastocytosis than the general population (1/100 children).
What makes this finding even more impressive is that mastocytosis is a rare disease occurring in 1/4000
children and is characterized by many hypersensitive mast cells in many tissues; once would, therefore,
expect that the combined prevalence would have been 1/100x1/4,000=1/400,000 and not 1/10 children! We
also found that the neuropeptide neurotensin, which is a pogtent mast cxell trigger, is statistically much
higher in the serum of autistic patients. We are investigating the presence of additional biomarkers in the
serum of autistic patients, the effect of stress (CRH) and environmental (mercury) triggers on the action of
neurotensin on mast cells, as well as the potential benefit of a flavonoid formulation for the treatment of
autism.
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