Immune Signature of Palmoplantar Pustulosis
Condition: Palmoplantar Pustulosis
MeSH terms: Psoriasis
Study type: Observational

Summary: 
      This study is being done to learn more about a less common "type" of psoriasis, called
      palmoplantar pustulosis (PPP). The majority of the current treatments used for this type of
      psoriasis have only a moderate effect on PPP. Thus, the investigators believe that PPP may be
      a different disease entity altogether, requiring different therapies. As such, the
      investigators hope to discover an immune signature for this condition.

      An immune "signature" is the unique way in which the combination of genes, cells, and
      proteins of the immune system work for each person. Because both psoriasis and the type of
      psoriasis patients have been diagnosed with, PPP, are conditions of abnormal immune system
      function, it is important to understand the overall function of the immune system in this
      condition (that is, find the immune "signature"). This study should help identify an immune
      system "signature" in people with PPP.

      The investigators have a laboratory technology which allows them to read the genetic
      "signatures" of a person's blood cells. Genes contain the instructions for making living
      things. Genes are contained in the cells' DNA (deoxyribonucleic acid). Most DNA is the same
      among humans, but the small differences people have in their DNA may explain why people
      develop different diseases. DNA and the genes it contains help produce RNA (ribonucleic
      acid), which in turn helps make proteins in people's cells. Differences in the types of
      proteins and the amount of those different proteins people's cells produce can affect a
      person's immune system.

      To help the investigators determine the immune "signature" in PPP, they will be examining the
      different genes, cells, and proteins that are active in patients with PPP versus patients who
      do not have the condition. The investigators will examine these genes, cells, and proteins in
      skin (through a skin sample) and in blood (through a blood draw). The goal is to develop new
      treatments for this skin condition. To do this, the investigators need to compare the skin
      and blood of patients with this particular type of psoriasis to the samples of healthy
      patients.
    

Detailed description: 
      I. SPECIFIC AIM

      Specific Aim. To identify transcriptional signatures in the skin and blood of patients with
      palmoplantar pustulosis (PPP).

      II. BACKGROUND AND SIGNIFICANCE

      Despite major advances in elucidating the molecular pathways of chronic plaque psoriasis
      (CPP), the immunopathogenesis of PPP, a less common "variant" of psoriasis, remains elusive.
      It is characterized by the development of inflammatory sterile pustules on the palms and
      soles of affected individuals, which can be exceptionally painful, interfering with walking
      and manual activities and impinging significantly on quality of life. Current systemic and
      biologic treatments used to treat CPP have only a moderate effect in patients with PPP,
      supporting the suggestion that PPP is a separate disease entity with a distinct
      immunopathogenic basis. Moreover, the spontaneous paradoxical development of PPP is
      frequently observed in patients treated with anti-tumor necrosis factor-α therapies, agents
      typically used in the treatment of CPP. Genetic analysis also distinguishes patients with PPP
      from those with CPP.

      At the investigators' institution, microarray analyses of blood transcriptional patterns have
      permitted crucial advances in characterizing the immunopathogenesis of immune-mediated
      conditions such as systemic lupus erythematosis and systemic-onset juvenile idiopathic
      arthritis. The investigators now wish to examine transcriptional profiles in the skin and
      blood of patients with PPP to identify the immunopathogenesis of this condition and identify
      potential therapeutic targets. The investigators will validate the findings at a cellular and
      protein level using flow cytometry, immunohistochemistry and measuring serum levels of
      proteins in the blood with Luminex or ELISA.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        1. Number of Subjects

             A total of 20 patients with palmoplantar pustulosis and 10 healthy controls will be
             enrolled in this study.

          2. Recruitment Procedures

        Subjects will be recruited from: (1) the dermatology clinic at Texas Dermatology (in
        conjunction with Menter Dermatology Research Institute) which include patients seen in the
        clinic referred by the dermatologists providing their care, participants of clinical trials
        in the clinic, or previously screened participants for clinical trials referred by the
        study staff); (2) referrals from other dermatologists' or doctors' clinics.

        Healthy volunteers will be recruited from the dermatology clinic. Where possible, healthy
        volunteers and PPP patients will be matched for sample collection location, gender, age and
        race.
      
Biospecimen description: 
      Blood and tissue samples. Blood from PPP patients. Skin biopsies from affected palms and
      soles.
    
Keywords: palmoplantar pustulosis; psoriasis