Tehran University Medical Journal

Primary immunodeficiency diseases (PIDs) is a diverse group of diseases, characterized by a defect in the immune system. These patients are susceptible to recurrent respiratory infections, gastrointestinal problems, autoimmune diseases, and malignancies. In most cases, patients with primary immunodeficiency disorders have genetic defects and are monogenic disorders that follow a simple Mendelian inheritance, however, some PIDs recognize a more complex polygenic origin. Overall, almost 70 to 90 percent of patients with primary immunodeficiency are undiagnosed. Given that these patients are exposing to respiratory infectious agents and some live-attenuated vaccines, thus they have a high risk to some clinical complications. The administration of oral polio vaccine in patients with PIDs especially can increase the possibility of acute flaccid paralysis. These patients will excrete the poliovirus for a long time through their feces, even though they are not paralyzed. Long-term virus proliferation in the vaccinated individuals causes a mutation in the poliovirus and creates a vaccine-derived polioviruses (VDPVs), which is a major challenge to the final stages of the worldwide eradication of polio. 
To increase the diagnosis and identification of patients with immunodeficiency and carrying out a national plan for screening patients with immunodeficiency from the fecal excretion of the poliovirus, a possible polio epidemic can be prevented during post-eradication. Development of laboratory facilities in provincial and city centers, improvement of communications among physicians regarding medical consultation and establishment of referring systems for patients by national network lead to improve status of diagnosis and treatment of patients with primary immunodefiicencies. In this context, launching and activating the national network of immunodeficiency diseases is essential for improving the health of children and reducing the cost of the health system of the country. A national network of immunodeficiency can lead to increase awareness of physicians regarding primary immunodeficiency disorders, improve collaboration among physicians about genetic consultation and establish a practical referral system in Iran that results in increased diagnosis and improve treatment of patients with primary immunodeficiency disorders.

Chick embryos are a great historical research model in basic and applied sciences. Along with other animal models, avian and specifically chicken embryo has been attended, as well. Avian fertilized eggs as a natural bioreactor are an efficient tool for producing recombinant proteins and vaccines manufacturing. Due to the limitations of birds' eggs for viral replication, avian stem cells culture technologies access to safe methods as well as large-scale production of a variety of human and animal vaccines. Chicken pluripotent stem cells present the unique property of self-renewal and the ability to generate differentiated progeny in all embryonic lineages such as ectoderm, mesoderm, and endoderm in vitro. For the first time, chicken embryonic stem cells (cESCs) derived from the blastodermal cells of stage X embryos in vitro. Chicken ESC provides a great model of early embryo and they are useful for gene manipulation, virus proliferation, and the generation of transgenic birds. In addition to blastodermal cells, pluripotent cell lines can be produced by reprogramming of chicken fibroblasts into induced pluripotent stem cells (iPSCs) with transcription factors such as OCT4, NANOG, SOX2, KLF4, LIN28, and C-MYC that are well known to contribute to the reprogramming of somatic cells into an iPSCs. Similar to chicken ESCs, iPSCs have properties of unlimited self-renewal in vitro and the capacity for differentiation to all three embryonic germ layers. Chicken iPSCs have been a useful tool for the production of transgenic birds and viral vaccines. Despite the benefits and multiple applications of chicken pluripotent stem cells, the propagation of these cells is limited and some important challenges should be eliminated before their use in vaccine manufacturing. It is necessary to define the appropriate culture conditions for chicken pluripotent stem cells. For example, the presence of endogenous viruses in the avian species should be evaluated for human vaccine production. Currently, primary chicken fibroblast cells are still mainly used for vaccine production. This review covers the resources to achieve chicken derived cell lines for vaccine manufacturing.