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Areas of ResearchDr. Albani and his lab are involved in the following areas of research and seek to advance the field of autoimmunity and develop novel effective treatments for use in the clinic.
Definition and manipulation of antigen-specific T cells in autoimmune inflammation.Immune responses to heat shock proteins (HSP) are ubiquitously found in inflammatory conditions. Teleologically, immune recognition of HSP evokes a potent and ancestral pro-inflammatory response, which has as objective the clearance of a perceived microbial infection. This mechanism has evolved into a sophisticated tool to modulate inflammation independently of its original trigger and it is often found in many conditions in which amplification of inflammation may be physiologically useful. Indeed, inflammation in itself is a stressful stimulus, which leads to local overexpression of HSP, leading to a potential amplification and perpetuation of the inflammatory process, even if the original trigger has become irrelevant to the process. It is therefore not surprising that immune responses to HSP are found ubiquitously in both physiologic and pathologic inflammatory conditions, including infection, autoimmunity and atherosclerosis. Regulatory mechanisms have evolved to modulate intensity and duration of this trigger independent inflammatory loop, in order to prevent damage. These mechanisms are often impaired in autoimmunity and their restoration may be one of the objectives of a trigger-independent approach to antigen specific immunotherapy. The task is not, however, and easy one. HSP are large proteins which, when processed, give raise to a multitude of potential epitopes of which only a few are dominant. In addition, as we have recently shown, different epitopes from the same HSP in the same disease may have very different functional effects on the immune response, some being pro-inflammatory, some others tolerogenic. Hence, the first hurdle is to identify epitopes, rather than proteins, which are recognized by a majority of patients, and to characterize appropriately the quality of such immune recognition in or to identify the most “pro-inflammatory” epitope if induction of tolerance is the desired goal. In our experience, we have pre-designed in silico the peptides based on the computerized prediction of agretopic motifs which may enable the putative antigens to be a strong pan-HLA class II binder. Theoretical binding scores are then matched with measurement of actual binding to isolated HLA molecules in vitro. This approach generates a pool of candidate peptides whose immunogencity is then screened in vitro against biological samples from patients. The quality of immune response toward the individual peptides, and in particular, the pro-inflammatory or tolerogenic connotation of such response is the parameter, which identifies the lead target for further development. This strategy has proven to be very effective in rapidly identifying epitopes in various disease settings such as RA, MS, IBD, and JIA. In our most advanced program, we have identified a 15mer derived from the e.Coli HSP dnaJ (dnaJP1) as a strong pro-inflammatory epitope in patients with active rheumatoid arthritis.. With a primary objective to restore mechanisms of impaired regulation of the HSP pro-inflammatory system, we embarked in a clinical program which has recently completed pilot Phase II trial. The peptide was given orally once a day for six months. Results from the first two phases could be summarized as follows: i) the approach is certainly safe and well tolerated; ii) an immune deviation from pro-inflammatory to tolerogenic T cell responses was induced in treated patients. This immune deviation, in particular the decline in TNFa production and corresponding increase in IL-10, may have a value as biomarker predictor or surrogate of clinical efficacy; iii) an improvement of signs and symptom of RA was observed. An analysis of the mechanisms of molecular immunology, which underlie the immunological and clinical effects of the treatment, is still underway at the time of this writing. Available data point to an overlapping of several different mechanisms in determining both clinical and immunological effects. These mechanisms include immune deviation of dnaJP1 specific T cells as well as restoration of Treg function, as evidenced by the significant increase in IL-10 and Foxp3 expression by dnaJP1, CD4-CD25++ T cells.
Investigational drug development for cytomegalovirus (CMV).The core of this program involves identification of optimal immunogenic peptides for the in vivo expansion of epitope-specific T cells. Experiments focus on the ability of the course of adoptive immunotherapy to restore immune response to CMV in immunodeficient patients by using T effectors acquired by sAPC expansion. The lab anticipates this cellular therapy technology to be applicable to other fields, including other infectious diseases, cancer and autoimmune disorders.
Identification and manipulation of regulatory T cells.One of the key players of immune regulation is the CD4+ CD25+ regulatory T cells (Treg). These spontaneously occurring T cells can prevent both the activation and the effector function of autoreactive T cells that escape other mechanisms of tolerance. The lab has examined the phenotype and function of these Treg in various models of autoimmunity to analyze whether CD4+ CD25+ Treg play a role in the reversal of the autoimmune process and whether differences in expression of this regulatory cell population can explain the difference in clinical course.
Summary of work in Pediatrics.The Albani lab has extensive experience in the field of pediatric autoimmune research that spans nearly two decades. Investigating the presence and response of autoantibodies in children and juveniles in a variety of settings (control groups, dermatomyositis, connective tissue diseases, rheumatoid arthritis, chronic arthritis, systemic lupus erythematosus and juvenile idiopathic arthritis, among others).
Adjuvant Arthritis model.Current anti-cytokine approaches remain hampered with limitations associated with generalized immunosuppresion and subsequent increased occurrences of malignancies and infectious diseases. Conceptually, therapeutic intervention focused on modulation of T cell function could represent a major addition to the available standard treatments of rheumatoid arthritis (biologicals and other second-line agents). Continuing on the question of how autoreactive T cells are regulated, Dr. Albani’s laboratory works extensively on identification of immune regulatory mechanisms in Adjuvant Arthritis model of arthritis. A major part of this work focuses on whether epitope specific and anti-cytokine therapy can be complementary, and if such synergy may be advantageous in order to exploit modulation of adaptive immunity while reducing generalized immune suppression and side effects. Utilizing the adjuvant arthritis model in rats, his group has shown that nasal administration of a 9-mer peptide (180-188) encompassing a single arthritogenic T cell epitope of mycobacterium head shock protein 60 leads to T cell tolerance. He has also demonstrated that antigen-specific therapy in combination with low dose anti-TNFa and DMARD (Methotrexate) therapy results in a significant reduction of arthritis clinically, to a degree entirely comparable with the full dose treatment regimens. Analysis of the underlying immunological mechanisms shows an induction of T cell immune deviation as well as a marked increase in the percentage of CD4+CD25hiFoxP3+ T cells following epitope-specific combination therapy. These findings can contribute to the development of new immunotherapies in rheumatoid arthritis and lay the foundation for designing an optimal biologic therapy based on the combination of anti-cytokine and T cell epitope specific approaches.
The Albani Lab is affiliated with the EUREKA Institute for Translational Medicine
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