Single-cell landscape analysis unravels molecular programming of the human B cell compartment in chronic GVHD.

Epidermis of the skin constitutes the largest organ and the outer most barrier of the body. It is one of the few organs that undergo lifelong self-renewal through a tight balance of cell growth, differentiation, and programmed cell death. Deregulation of this balance is manifested in many diseases, including various immune diseases and cancer. 

Our lab is focused on 3 interrelated topics:

1. Gene regulation of epithelial cell proliferation and differentiation

Using regenerated human skin tissues and murine genetic models, we have demonstrated important functions NF-kB and AP-1 gene regulators in epidermal cell growth and differentiation. Currently, our efforts are focused on understating how loss-of-function of CYLD, a deubiquitinase and tumor suppressor, leads to the development of hair follicle defects, skin inflammation, and cancer. Specifically, we want to determine how CYLD integrates NF-kB, AP1, Myc, and other transcription factors to control epidermal cell growth and lineage differentiation.

De novo skin regeneration is life-saving procedure for severely burned patients and lethal genetic skin diseases such as epidermal bullosa. An additional aspect of our study is to improve new skin regeneration techniques and to create experimental skin disease models with gene transduced keratinocytes, as illustrated below.

2. Keratinocytes as instigators of inflammatory responses

Keratinocytes are constantly challenged by external insults, as well as immune cells. Disarray of the crosstalk between keratinocytes and immune cells underlies various immune diseases, including dermatitis, psoriasis, and cutaneous graft-versus-host disease (GVHD). GVHD is a common complication and the leading cause of non-relapse mortality among patients after receiving allogenic hematopoietic stem cell transplantation.  The skin is the most commonly affected organ in both the acute and chronic forms of this disease.  Treatment options for GVHD are limited and the current standard therapy is high dose systemic corticosteroid which is itself associated with significant morbidity. Our goal is to understand how keratinocytes contribute to the progression of GVHD, and may therefore be targeted to mitigate the disease.

3. Ubiquitination enzymes in melanoma

Melanoma most lethal and difficult to treat skin cancer. In the recent years, BRAF/MEK-targeted therapies have produced exciting results, but they suffer from short duration. Our goal is to uncover novel mechanisms crucial for melanoma malignancy. Specifically, we want to understand how ubiquitination enzymes contribute to melanoma growth. Previously, we have demonstrated that CYLD inhibits melanoma growth through suppression of JNK/AP1 and b1-integrin signaling pathways. In contrast, UBE2N, a K63-Ubiquitin conjusage, promotes melanoma growth in part through activation of the MEK/FRA/SOX10 signaling cascade. Currently, our efforts are focused on understanding how UBE2N and other ubiquitin enzymes regulate the MAPK signaling pathway and whether they can be targeted for melanoma therapy.

Allogeneic stem cell transplantation with a focus on the use of umbilical cord blood grafts; Allogenic stem cell transplantation for Sickle Cell Disease; Prevention of acute and chronic graft versus host disease; Improving immune recovery following alternative donor stem cell transplantation using donor graft manipulation.

My research interests are in two broad areas, clinical hematopoietic stem cell and cord blood transplantation and in the laboratory studies related to graft vs. host disease and immune reconstitution. On the clinical side we are currently conducting approximately 50 different clinical protocols ranging from preparatory regimens, supportive care studies and disease specific protocols. Most of these clinical studies are centered around studies of the sources of stem cells and the methods to improve the long term outcome. There are exploratory protocols for novel therapies such as dendritic cell therapy for several malignancies, antiangiogenesis therapy, graft engineering to prevent graft-versus-host disease and antigen specific T cells or non specific NK cells to prevent relapse. Moreover a strong focus of the program is to develop cord-blood transplantation for adult patients with hematologic malignancies. The laboratory studies center on understanding the immunological events that occur with graft-vs-host disease and methods to prevent this disease. The current efforts focus on understanding murine reconstitution following transplantation, use of a peptide polymer to block MHC class II recognition of minor histocompatibility antigens, use of T cell engineering to prevent graft-versus-host disease at the same time preserving a graft-versus-malignancy effect.

For more information see http://ed-media.mc.duke.edu/BMT.nsf

cancer pharmacogenomics
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statistical methods for high-dimensional data
copulas
survival analysis
statistical computing