Activation and upregulation of keratinocyte and epidermal transglutaminases are associated with depletion of their substrates in psoriatic lesions.

OBJECTIVE: Psoriasis is a chronic skin disorder caused by abnormal interactions between epidermal and immune cells. Thus, the interplay between the proliferation and differentiation of epidermal components should be tightly regulated to protect against psoriasis. The differentiation process is primarily controlled by transglutaminases (TGs). However, studies on TG enzymes and their molecular alterations in psoriatic skin lesions are limited. Therefore, this study aimed to investigate TG activity and gene and protein expression in human psoriatic and normal skin tissues. MATERIALS AND METHODS: Keratinocyte TG (TG1), and epidermal TG (TG3) activity, localization, protein levels, and gene expression in human psoriatic skin were determined by immunohistochemistry and RT-qPCR. The expression of TG substrates (loricin and involucrin - IVL) was also investigated using RT-qPCR. RESULTS: TG1 and TG3 enzymatic activities and gene expression were significantly higher in psoriatic skin tissue than in normal skin tissue. However, both TGs were present in the same location and were equally highly expressed. Moreover, the expression of two TG substrates (loricin and involucrin) was significantly decreased compared to that in psoriatic and healthy skin samples. CONCLUSIONS: The activation and upregulation of TG1 and TG3 result from the depletion of their substrates (loricin and involucrin), both of which play a major role in the pathogenicity of psoriatic skin tissue and are necessary for proper skin development.

The Saudi Thoracic Society pneumococcal vaccination guidelines-2016.

Streptococcus pneumoniae (pneumococcus) is the leading cause of morbidity and mortality worldwide. Saudi Arabia is a host to millions of pilgrims who travel annually from all over the world for Umrah and the Hajj pilgrimages and are at risk of developing pneumococcal pneumonia or invasive pneumococcal disease (IPD). There is also the risk of transmission of S. pneumoniae including antibiotic resistant strains between pilgrims and their potential global spread upon their return. The country also has unique challenges posed by susceptible population to IPD due to people with hemoglobinopathies, younger age groups with chronic conditions, and growing problem of antibiotic resistance. Since the epidemiology of pneumococcal disease is constantly changing, with an increase in nonvaccine pneumococcal serotypes, vaccination policies on the effectiveness and usefulness of vaccines require regular revision. As part of the Saudi Thoracic Society (STS) commitment to promote the best practices in the field of respiratory diseases, we conducted a review of S. pneumoniae infections and the best evidence base available in the literature. The aim of the present study is to develop the STS pneumococcal vaccination guidelines for healthcare workers in Saudi Arabia. We recommend vaccination against pneumococcal infections for all children <5 years old, adults ≥50 years old, and people ≥6 years old with certain risk factors. These recommendations are based on the presence of a large number of comorbidities in Saudi Arabia population <50 years of age, many of whom have risk factors for contracting pneumococcal infections. A section for pneumococcal vaccination before the Umrah and Hajj pilgrimages is included as well.