First Serological & Molecular Study of Coxiella burnetii in Stray, Domestic Cats, and Their Owners in Iran.

Coxiella burnetii, the agent of Q fever, is recognized as a worldwide zoonosis a wide host and potentially complex reservoir systems. Infected ruminants are the main source of infection for humans, but cats also represent a potential source of infection. The prevalence of C burnetii in cats in Iran is unknown and the risks of transmission to humans are undetermined. This study aimed to determine the prevalence of C burnetii in domestic cats and their owners. An Enzyme-linked immunosorbent assay was used for detection of anti-C burnetii antibodies in both cats and humans. Cats serum samples and humans serum samples (n = 85) were tested with indirect ELISA. C burnetii was diagnosed using real time- polymerase chain reaction. Antibodies were detected in 19 sera of 85 (22.35%) samples in stray cats, 9 sera of 78 (11.53%) samples of domestic cats and 4 sera of 78 (5.12%) samples of their owners. This first study of C burnetii prevalence in cats in Iran has indicated that positive samples can be found throughout the country and these results confirm that Iranian cats have been exposed to C burnetii. Moreover, this study demonstrates that cat owners, breeders and veterinary personnel might be at higher risk of exposure of C burnetii.

Reciprocal role of hBD2 and hBD3 on the adaptive immune response by measuring T lymphocyte proliferation in terms of CD4 and CCR6 expression.

Background Human ß-defensins (hBD2 and hBD3) are small cationic antimicrobial peptides of innate immune system which can act as a barrier against the majority of pathogens, contributing to the host immune defence. Objective The aim of study is to determine whether hBD2 and hBD3 play a role in development and proliferation of human effector CD4 T cells or not. Furthermore, if enhanced proliferation is observed in the presence of hBD2 and hBD3, these data will demonstrate whether chemokine receptor type 6 (CCR6) is required to be present for this activity to occur. Methods In this study, we examined the effect of hBD2 and hBD3 on CD4+ T cell proliferation in CCR6+ and CCR6- T cells through co-culture of peripheral blood mononuclear cells with anti-CD3 and anti-CD28 stimulation in the presence or absence of hBD2 and hBD3. Proliferation was assessed using flow cytometry. Results It was demonstrated that, co-culture with hBD2 and hBD3 led to up-regulation of CD4+ T cell proliferation after 72 h whereas, CD4+ T cell proliferation was suppressed after 96 h. On the other hand, CCR6- and CCR6+ T cell proliferation was up-regulated after 72 h. But, CCR6+ only was down-regulated in the second cycle in the presence of hBD3. In contrast, after 96 h CCR6+ and CCR6- T cell proliferation was decreased. Conclusion Collectively, our data indicated that hBD2 and hBD3 play a positive and negative regulatory role in development and proliferation of human effector CD4+ T cells which is essential for optimal adaptive immune responses and the control of immunopathology.

Early growth response 2 and Egr3 are unique regulators in immune system.

The immune system is evolved to defend the body against pathogens and is composed of thousands of complicated and intertwined pathways, which are highly controlled by processes such as transcription and repression of cellular genes. Sometimes the immune system malfunctions and a break down in self-tolerance occurs. This lead to the inability to distinguish between self and non-self and cause attacks on host tissues, a condition also known as autoimmunity, which can result in chronic debilitating diseases. Early growth response genes are family of transcription factors comprising of four members, Egr1, Egr2, Egr3 and Egr4. All of which contain three cyc2-His2 zinc fingers. Initially, Egr2 function was identified in the regulation of peripheral nerve myelination, hindbrain segmentation. Egr3, on the other hand, is highly expressed in muscle spindle development. Egr2 and Egr3 are induced due to the antigen stimulation and this signaling is implemented through the B and T cell receptors in the adaptive immunity. T cell receptor signaling plays a key role in Egr 2 and 3 expressions via their interaction with NFAT molecules. Egr 2 and 3 play a crucial role in regulation of the immune system and their involvement in B and T cell activation, anergy induction and preventing the autoimmune disease has been investigated. The deficiency of these transcription factors has been associated to deficient Cbl-b expression, a resistant to anergy phenotype, and expression of effector and activated T cells.