Neuronal synapse is the critical structure of neuronal network. Immune system is mainly consisted of invisible network. Recently, evidence showed that leukocyte synapses between immune cells named as immunological synapses (IS), were formed under some functional conditions to form temporal local network. In fact, they are dynamic structures, which can be classified into synapse and kinase. Different leukocytes have different synapses. Inflammatory and leukemic cells showed special patterns of IS. Similar structure is also observed in some viral infected lymphocytes, which is called virological synapse (VS). This is one of the mechanisms for viral transmission, not only enhancing the transmission efficiency but also mediating the escape from antibody neutralization, leading persistent infection. Recently the flower-like poly synapses was reported by French scientists. This is a multi-tunneling nanotube flower-like structure on cell surface. We had observed this kind of structure in EB virus infected human leukemic cell line J6-2. In this paper, the structure and function of leukocyte synapses are reviewed combined with authors' own work. Their significance is discussed.
Humans ; Immunological Synapses ; immunology ; physiology ; Leukocytes ; cytology ; immunology ; physiology ; virology

Exercise capacity is a valuable trait in horses, and it has been used as a horse selection criterion. Although exercise affects molecular homeostasis and adaptation in horses, the mechanisms underlying these effects are not fully described. This study was carried out to identify changes in the blood profiles of microRNAs (miRNAs) and mRNAs induced by exercise in horse leukocytes. Total RNAs isolated from the peripheral blood leukocytes of four Warmblood horses before and after exercise were subjected to next-generation sequencing (NGS) and microarray analyses to determine the miRNA and mRNA expression profiles, respectively. The expressions of 6 miRNAs, including 4 known and 2 novel miRNAs, were altered by exercise. The predicted target genes of the differentially expressed miRNAs identified by NGS were matched to the exercise-induced mRNAs determined by microarray analysis. Five genes (LOC100050849, LOC100054517, KHDRBS3, LOC100053996, and LOC100062720) from the microarray analysis were matched to the predicted target genes of the 6 miRNAs. The subset of mRNAs and miRNAs affected by exercise in peripheral blood leukocytes may be useful in elucidating the molecular mechanisms of exercise-associated physiology in horses.
Homeostasis ; Horses ; Leukocytes ; Microarray Analysis ; MicroRNAs ; Physiology ; RNA ; RNA, Messenger

The adhesion of leukocytes to substrate is an important biomedical engineering problem and has drawn extensive research. In this study, we have proposed a compound drop model to simulate a leukocyte with a nucleus adhered to the surface of a blood vessel under steady shear flow. A two-dimensional computational fluid dynamics (CFD) is conducted to determine the local distribution of pressure on the surface of the adherent model cell. By introducing the parameter of deformation index (DI), we have investigated the deformation of the model cell and it's nucleus under controlled conditions. Our numerical results show that: (1) the model cell is capable of deformation with the increase of initial contact angle, capillary number, and Reynolds number, and that the cytoplasm is more deformable while the nucleus is more capable of resisting external imposed shear flow; (2) the model cell is not able to deform infinitely with the increase of external shear flow because the deformation index reaches a maximum; (3) pressure distribution confirms that there exists a region downstream of the cell, which produces high pressure to retard continuous deformation and provide a positive lift force on the cell. Our results of nucleus deformation may help to develop a better understanding of how leukocytes transduce external mechanical signal like shear stress into nucleus.
Biomechanical Phenomena ; Blood Vessels ; cytology ; physiology ; Cell Adhesion ; physiology ; Cell Nucleus ; physiology ; Leukocytes ; physiology ; Models, Cardiovascular ; Numerical Analysis, Computer-Assisted

The movement of leukocytes from the blood into peripheral tissues is a central feature of immune surveillance, but also contributes to the pathogenesis of inflammatory and autoimmune diseases. Integrins are a family of adhesion and signaling molecules made up of paired alpha and beta subunits, and the integrin alpha4beta1 plays a prominent role in the trafficking of mononuclear leukocytes. We have previously described the direct interaction of the signaling adaptor molecule paxillin with the cytoplasmic domain of the alpha4 integrin subunit. This interaction is critical for alpha4beta1 integrin dependent cell adhesion under shear flow conditions as it provides a needed connection to the actin cytoskeleton. Furthermore, the alpha4-paxillin interaction is required for effective alpha4beta1 dependent leukocyte migration and does so through the temporal and spatial regulation of the small GTPase Rac. These findings make the alpha4-paxillin interaction a potentially attractive therapeutic target in controlling leukocyte trafficking.
Protein Binding ; Paxillin/*metabolism/physiology ; Models, Biological ; Leukocytes/cytology/*metabolism ; Integrin alpha4beta1/metabolism/physiology ; Integrin alpha4/*metabolism/physiology ; Humans ; Cell Movement/*physiology ; Cell Adhesion/physiology

A theoretical model was developed to simulate the coupling between the adhered leukocyte and blood flow. Methods of computational fluid dynamics (CFD) were introduced to analyze the distributions of the shear stress and the pressure on the cell surface. Meanwhile, the hemodynamical parameters were measured with laser Doppler velocimetry. The results showed that the deformation index of the leukocyte was increased with initial contact angle and Reynolds number. The blood flow induced the redistributions of the shear stress and pressure on the surface of the cell, but the maximum shear stress was on the top point of the cell. It suggests that the non-uniform distribution of shear stress on the cell surface may play a particular role in the change of cell shape and functions.
Blood Circulation ; physiology ; Cell Adhesion ; Hemodynamics ; Humans ; Leukocytes ; cytology ; physiology ; Models, Biological ; Regional Blood Flow ; Shear Strength

CKLF-like MARVEL transmembrane domain containing member/chemokine-like factor super family member (CKLFSF/CMTM) is a novel tumor suppressor gene. CMTM3 is broadly expressed in normal human tissues and evolutionary conserved,especially in testis,spleen,and some cells of peripheral blood mononuclear cells. However,its expression is undetectable or down-regulated in most carcinoma cell lines and tissues. Restoration of CMTM3 may inhibit the proliferation,migration,and invasion of carcinoma cells. Although the exact mechanism of its anti-tumor activity remains unclear,CKLFSF3/CMTM3 is closely connected with immune system and associated with sex during tumorigenesis. The study advances of CKLFSF3/CMTM3 are elaborated in this review as CMTM3 may be a new target in the gene therapies for tumors,especially genitourinary tumors,while further studies on CMTM3 and its anti-tumor mechanisms are warranted.
Cell Transformation, Neoplastic ; Chemokines ; genetics ; physiology ; Down-Regulation ; Humans ; Leukocytes, Mononuclear ; MARVEL Domain-Containing Proteins ; genetics ; physiology ; Male ; Neoplasms ; pathology

Blood Coagulation ; physiology ; Blood Platelets ; metabolism ; Cell Communication ; Factor X ; metabolism ; Humans ; Leukocytes ; metabolism ; Thromboplastin ; metabolism ; physiology

Johne's disease is a condition that refers to chronic granulomatous enteritis in ruminants. It is believed that survival and replication of Mycobacterium (M.) paratuberculosis in mononuclear phagocytes plays an important role in the pathogenesis of Johne's disease. However, it is not clear how M. paratuberculosis survives for long time periods in mononuclear phagocytes, nor is it clear which factors trigger multiplication of these bacilli and result in the development of Johne's disease. Investigating the intracellular fate of M. paratuberculosis is challenging because of its very slow growth (more than two months to form visible colonies on media). Existing animal models also have limitations. Despite those obstacles, there has been progress in understanding the intracellular survival tactics of M. paratuberculosis and the host response against them. In this review, we compare known aspects of the intracellular survival tactics of M. paratuberculosis with those of other mycobacterial species, and consider possible mycobactericidal mechanisms of mononuclear phagocytes.
Animals ; Leukocytes, Mononuclear/*microbiology ; Mycobacterium avium subsp. paratuberculosis/*physiology ; Phagocytes/*microbiology

The influencing factors on cord blood storage after collection and mononuclear cell separation as well as cryopreservation were studied. The mononuclear cell are separated from blood after blood collection, then cryopreserved and washed after thawed. Results showed that the cord blood kept at 4 degrees C or room temperature less than 24 hours after blood collection, mononuclear cell separated by hydroxyethylstarch and 2 centrifugations, mononuclear cell cryopreserved with 50% DMSO and autoplasma from cord blood as protectives and washing the cells after thawing. In conclusion, the optimal project in this study can effectively preserve cord blood mononuclear cells.
Blood Preservation ; Cell Separation ; methods ; Cryopreservation ; Fetal Blood ; cytology ; Humans ; Leukocytes, Mononuclear ; physiology

Pyospermia is an abnormal laboratory finding of high concentration of white blood cells in human ejaculates during infertility workup. The role of pyospermia and its impact on fertility is an important consideration in the management of infertility. Etiology, pathogenesis, diagnostic modalities and the management of pyospermia are reviewed in this paper. Current use of antibiotics and the intrinsic production of antioxidants in the management of pyospermia are also discussed in this review.
Diagnosis, Differential ; Ejaculation ; Humans ; Infertility, Male ; diagnosis ; etiology ; physiopathology ; therapy ; Leukocytes ; physiology ; Male