Search

We present a case in which a Naval aviator suffered an unusual sequence of neuropsychiatric symptoms after head trauma. He demonstrated subtle deficits on several measures 1 mo after the trauma. Repeat testing at 8 mo showed apparent recovery, and the patient was cleared to return to flight status. Unbeknownst to medical staff, the patient was still experiencing difficulties. He was found in a severely debilitated state and exhibiting psychotic features 12 mo after his initial trauma. The patient was hospitalized in a psychiatric ward, and with prolonged inpatient and outpatient treatment, he eventually recovered.

Catalysts for the water gas shift reaction contain a variety of late transition metals. The catalytic compositions contain a late transition metal carried on a support which is a carbide, nitride, or mixed carbide nitride of a group 6 metal such as molybdenum, tungsten, and mixtures thereof. The late transition metal includes ruthenium, cobalt, nickel, palladium, platinum, copper, silver, or gold. The water gas shift reaction may be catalyzed by contacting a gaseous stream containing carbon monoxide and water with such a solid catalyst composition. In some embodiments, the catalysts are several times more active than known commercial catalysts for the water gas shift reaction.

Directed cellular migrations underlie immune system organization. Chemokines and their receptors (along with surface-adhesion molecules) are central to these migrations, targeting developing and mature leukocytes to tissues and microenvironments suitable for their differentiation and function. The chemokine CXCL12 and its receptor CXCR4 play a central role in the migration of hematopoietic stem cells, and several chemokine receptors are transiently expressed during distinct stages of B- and T-cell development. In the periphery, mature naïve B and T cells utilize the receptors CCR7, CXCR4, and CXCR5 to recirculate through specialized microenvironments within the secondary lymphoid tissues, while effector and memory lymphocytes express bewildering patterns of adhesion molecules and chemokine receptors that allow them to function within microenvironments and non-lymphoid tissues inaccessible to naïve cells. Here, we summarize the role of chemokines and their receptors in the spatial organization of the immune system and consider the implications for immune function.

NKT cells play important roles in the regulation of diverse immune responses. Therefore, chemokine receptor expression and chemotactic responses of murine TCRalphabeta NKT cells were examined to define their homing potential. Most NKT cells stained for the chemokine receptor CXCR3, while90% of Valpha14i-positive and approximately 50% of Valpha14i-negative NKT cells expressed CXCR6 via an enhanced green fluorescent protein reporter construct. CXCR4 expression was higher on Valpha14i-negative than Valpha14i-positive NKT cells. In spleen only, subsets of Valpha14i-positive and -negative NKT cells also expressed CXCR5. NKT cell subsets migrated in response to ligands for the inflammatory chemokine receptors CXCR3 (monokine induced by IFN-gamma/CXC ligand (CXCL)9) and CXCR6 (CXCL16), and regulatory chemokine receptors CCR7 (secondary lymphoid-tissue chemokine (SLC)/CC ligand (CCL)21), CXCR4 (stromal cell-derived factor-1/CXCL12), and CXCR5 (B cell-attracting chemokine-1/CXCL13); but not to ligands for other chemokine receptors. Two NKT cell subsets migrated in response to the lymphoid homing chemokine SLC/CCL21: CD4(-) Valpha14i-negative NKT cells that were L-selectin(high) and enriched for expression of Ly49G2 (consistent with the phenotype of most NKT cells found in peripheral lymph nodes); and immature Valpha14i-positive cells lacking NK1.1 and L-selectin. Mature NK1.1(+) Valpha14i-positive NKT cells did not migrate to SLC/CCL21. BCA-1/CXCL13, which mediates homing to B cell zones, elicited migration of Valpha14i-positive and -negative NKT cells in the spleen. These cells were primarily CD4(+) or CD4(-)CD8(-) and were enriched for Ly49C/I, but not Ly49G2. Low levels of chemotaxis to CXCL16 were only detected in Valpha14i-positive NKT cell subsets. Our results identify subsets of NKT cells with distinct homing and localization patterns, suggesting that these populations play specialized roles in immunological processes in vivo.

Ku70 (Lupus Ku autoantigen p70) is essential in nonhomologous end joining DNA double-strand break repair, and ku70−/− mice age prematurely because of increased genomic instability and DNA damage responses. Previously, we found that Ku70 also inhibits Bax, a key mediator of apoptosis. We hypothesized that Bax-mediated apoptosis would be enhanced in the absence of Ku70 and contribute to premature death observed in ku70−/− mice. Here, we show that ku70−/−bax+/− and ku70−/−bax−/− mice have better survival, especially in females, than ku70−/− mice, even though Bax deficiency did not decrease the incidence of lymphoma observed in a Ku70-null background. Moreover, we found that ku70−/− mice develop lung diseases, like emphysema and pulmonary arterial (PA) occlusion, by 3 months of age. These lung abnormalities can trigger secondary health problems such as heart failure that may account for the poor survival of ku70−/− mice. Importantly, Bax deficiency appeared to delay the development of emphysema. This study suggests that enhanced Bax activity exacerbates the negative impact of Ku70 deletion. Furthermore, the underlying mechanisms of emphysema and pulmonary hypertension due to PA occlusion are not well understood, and therefore ku70−/− and Bax-deficient ku70−/− mice may be useful models to study these diseases.

Hemopoiesis is regulated in part by survival/apoptosis of hemopoietic stem/progenitor cells. Exogenously added stromal cell-derived factor-1 ((SDF-1)/CXC chemokine ligand (CXCL)12) enhances survival/antiapoptosis of myeloid progenitor cells in vitro. To further evaluate SDF-1/CXCL12 effects on progenitor cell survival, transgenic mice endogenously expressing SDF-1/CXCL12 under a Rous sarcoma virus promoter were produced. Myeloid progenitors (CFU-granulocyte-macrophage, burst-forming unit-erythroid, CFU-granulocyte-erythrocyte-megakaryocyte-monocyte) from transgenic mice were studied for in vitro survival in the context of delayed addition of growth factors. SDF-1-expressing transgenic myeloid progenitors were enhanced in survival and antiapoptosis compared with their wild-type littermate counterparts. Survival-enhancing effects were due to release of low levels of SDF-1/CXCL12 and mediated through CXCR4 and Gαi proteins as determined by ELISA, an antagonist to CXCR4, Abs to CXCR4 and SDF-1, and pertussis toxin. Transgenic effects of low SDF-1/CXCR4 may be due to synergy of SDF-1/CXCL12 with other cytokines; low SDF-1/CXCL12 synergizes with low concentrations of other cytokines to enhance survival of normal mouse myeloid progenitors. Consistent with in vitro results, progenitors from SDF-1/CXCL12 transgenic mice displayed enhanced marrow and splenic myelopoiesis: greatly increased progenitor cell cycling and significant increases in progenitor cell numbers. These results substantiate survival effects of SDF-1/CXCL12, now extended to progenitors engineered to endogenously produce low levels of this cytokine, and demonstrate activity in vivo for SDF-1/CXCL12 in addition to cell trafficking.

The germinal center (GC) is a pivotal site for the development of B cell memory. Whereas GC B cells do not chemotax to most chemokines and do not express the adhesion receptors L-selectin, α4β7, and cutaneous lymphocyte Ag (CLA), memory B cells respond to various chemotactic signals and express adhesion receptors. In this study, we show that CD40 ligand, IL-2, and IL-10 together drive this transition of GC B cells to memory phenotype in vitro, up-regulating memory B cell markers, chemotactic responses to CXC ligand (CXCL)12, CXCL13, and CCL19, and expression of adhesion receptors L-selectin, α4β7, and CLA. Moreover, addition of IL-4 modulates this transition, preventing chemotactic responses to CXCL12 and CXCL13 (but not to CCL19), and inhibiting the re-expression of L-selectin, but not of CLA or α4β7. CCR7 expression, responsiveness to CCL19, and L-selectin/α4β7 phenotype are coordinately regulated. Thus, IL-2/IL-10 and IL-4 play important and distinctive roles in developing the migratory capacities of memory B cells.

Background: This study was conducted to identify genetic polymorphisms associated with the prognosis of patients with early stage non-small cell lung cancer (NSCLC). Materials and Methods: We genotyped 1,969 potentially functional single nucleotide polymorphisms (SNPs) of 1,151 genes using the Affymetrix custom-made GeneChip, which were related to the development and progression of cancer, in 166 NSCLC patients who underwent curative surgical resection. A replication study was performed on an independent cohort of 626 patients. Results: Fifty six SNPs which were associated with both overall survival (OS) and disease-free survival (DFS) with log-rank P values lower than 0.05 in a discovery set were selected for validation. Among the 56 SNPs, five SNPs (guanine nucleotide binding protein, beta polypeptide 2-like 1 [GNB2L1] rs1279736C>A and rs3756585T>G, complement component 3 [C3] rs2287845T>C, p300/CBP-associated factor [PCAF] rs17006625A>G, and pericentriolar material 1 [PCM1] rs17691523C>G) were found to be significantly associated with survival outcomes in the same direction as the discovery set. In combined analysis, the rs1279736C>A and s3756585T>G were most significantly associated with OS and DFS in multivariate analysis (P for OS = 4x10-5 and 7x10-5, respectively; and P for DFS = 0.003, both; under a codominant model). Conclusions: We identified five SNPs as markers for prognosis of patients with surgically resected NSCLC. Citation Format: Shin Yup Lee, Yi Young Choi, Hyo-Sung Jeon, Jin Eun Choi, Hyo-Gyoung Kang, Seung Soo Yoo, Eung Bae Lee, Won Kee Lee, Jaehee Lee, Seung Ick Cha, Chang Ho Kim, Ji Woong Son, Jae Yong Park. Polymorphisms in cancer-related genes and survival in early stage non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4721. doi:10.1158/1538-7445.AM2014-4721

Short chain acids (SCFAs) are highly produced by gut commensal bacteria and play important roles in regulating immune responses. SCFAs can regulate epithelial cells an dimmune cells, and some of the functions are mediated through GPR41 and GPR43. Epithelial cells highly express both GPR41 and GPR43, but the functions of these receptors in regulation of epithelial innate immunity remain unclear. To investigate this, we utilized mice deficient in expression of GPR41 or GPR43. When the gut barrier function was breached with 50% ethanol, GPR41-/- and GPR43-/- mice were defective in expression of inflammatory cytokines (IL-6, IL1b and TNFa) and chemokines (CXCL1 and CXCL2) in response to invading bacteria. When the mice were infected with C. rodentium, the KO mice were delayed in mounting immune responses and clearing the pathogen. On the other hand, wild type mice with increased levels of SCFAs were more efficient in expression of the inflammatory factors. The results of our bone marrow transfer and in vitro culture experiments indicate that epithelial GPR41 and GPR43 play critical roles in mediating the SCFA signal. SCFAs induced a series of signaling events from the surface receptors to ERKs and to ATF2 activation to express the inflammatory factors. These processes are required to recruit and activate immune cells to clear pathogenic bacteria. Our results revealed a novel positive role of short chain fatty acids and their receptors in regulating intestinal immunity.

Current concepts of chemokine receptor (CKR) association with Th1 and Th2 cell polarization and effector function have largely ignored the diverse nature of effector and memory T cells in vivo. Here, we systematically investigated the association of 11 CKRs, singly or in combination, with CD4 T cell polarization. We show that Th1, Th2, Th0, and nonpolarized T cells in blood and tissue can express any of the CKRs studied but that each CKR defines a characteristic pool of polarized and nonpolarized CD4 T cells. Certain combinations of CKRs define populations that are markedly enriched in major subsets of Th1 versus Th2 cells. For example, although Th0, Th1, and Th2 cells are each found among blood CD4 T cells coordinately expressing CXCR3 and CCR4, Th1 but not Th2 cells can be CXCR3(+)CCR4(-), and Th2 but only rare Th1 cells are CCR4(+)CXCR3(-). Contrary to recent reports, although CCR7(-) cells contain a higher frequency of polarized CD4 T cells, most Th1 and Th2 effector cells are CCR7(+) and thus may be capable of lymphoid organ homing. Interestingly, Th1-associated CKRs show little or no preference for Th1 cells except when they are coexpressed with CXCR3. We conclude that the combinatorial expression of CKRs, which allow tissue- and subset-dependent targeting of effector cells during chemotactic navigation, defines physiologically significant subsets of polarized and nonpolarized T cells.

We identified specialized B helper and tissue inflammatory CD4(+) T cell subsets that developed concurrently from common naive precursors during the primary immune response. These separable populations were distinguishable by their expression of adhesion and chemoattractant receptors that directed their homing to the appropriate effector sites in vivo and also showed intrinsic differences in their ability to support B cell antibody production and produce effector cytokines in vitro. Thus, our data show a previously unappreciated functional specialization among CD4(+) effector T cells, further defining their diversity and role in adaptive immunity.

Chemokines have been implicated in regulation of various aspects of hematopoiesis, including negative regulation of the proliferation of immature subsets of myeloid progenitor cells (MPCs), chemotaxis of MPCs, and survival enhancement of MPCs after delayed growth factor addition. Since chemokine receptors are seven-transmembrane-spanning G-protein-linked receptors and the chemotactic effect in vitro of the CXC chemokine SDF-1 is pertussis toxin (PT)-sensitive, implying the involvement of G alpha i proteins as mediators of SDF-1-induced chemotaxis, we evaluated the effects of PT on other chemokine actions influencing MPCs. While the in vitro survival-enhancing effects of SDF-1 on GM-CSF and steel factor-dependent mouse bone marrow granulocyte macrophage progenitors (CFU-GM) were pertussis toxin-sensitive, the suppressive effects of the CC chemokine MIP-1 alpha and the CXC chemokine IL-8 on colony formation by GM-CSF and steel factor-sensitive CFU-GM were insensitive to pertussis toxin. These results suggest that not all chemokine-mediated effects on MPCs are necessarily mediated through pertussis toxin-sensitive G alpha i proteins.

Purpose To evaluate the safety and efficacy of laser in situ keratomileusis (LASIK) in selected post-radial-keratotomy (RK) eyes with residual myopia and astigmatism. Setting TLC—The Brea Laser Eye Center, Brea, California, USA. Methods Nine eyes of 6 patients who had had RK but had residual myopia and/or astigmatism had LASIK. All RK eyes had 8 radial incisions, were more than 1 year post-RK, had no epithelial inclusion cysts or corneal disease, and had had no subsequent ocular surgery. Follow-up was a minimum of 13 months, at which time uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), manifest refraction, cycloplegic refraction, keratometry, central and peripheral pachymetries, intraocular pressure, and a subjective assessment of visual function were obtained. Results At the last follow-up, the mean spherical equivalent (SE) was −0.156 diopter (D) ± 0.174 (SD). All eyes treated for distance vision had a UCVA of 20/25 or better. No patient lost BCVA. No intraoperative or postoperative complications occurred. Seven eyes had morning and evening measurements. The mean change in manifest SE from morning to evening was −0.143 D. Six of the 7 eyes (86%) had 0 to 1 Snellen line change in UCVA from morning to evening. The subjective questionnaire revealed a high degree of satisfaction with overall vision, minimal glare, and less fluctuation in daily vision than before LASIK. Conclusion Laser in situ keratomileusis is safe and efficacious for reducing residual myopia and astigmatism in properly selected RK patients.

SHIP has been implicated in negative signaling in a number of hematopoietic cell types and is postulated to downregulate phosphatidylinositol-3-kinase– (PI-3K–) initiated events in diverse receptor signaling pathways. Because PI-3K is implicated in chemokine signaling, we investigated whether SHIP plays any role in cellular responses to chemokines. We found that a number of immature and mature hematopoietic cells from SHIP-deficient mice manifested enhanced directional migration (chemotaxis) in response to the chemokines stromal cell–derived factor-1 (SDF-1) and B-lymphocyte chemoattractant (BLC). SHIP–/– cells were also more active in calcium influx and actin polymerization in response to SDF-1. However, colony formation by SHIP-deficient hematopoietic progenitor cell (HPCs) was not inhibited by 13 myelosuppressive chemokines that normally inhibit proliferation of HPCs. These altered biologic activities of chemokines on SHIP-deficient cells are not caused by simple modulation of chemokine receptor expression in SHIP-deficient mice, implicating SHIP in the modulation of chemokine-induced signaling and downstream effects. J. Clin. Invest. 104:1751–1759 (1999).

Purpose To evaluate the effect of an intraoperative topical intrastromal steroid on the incidence and severity of nonspecific diffuse intralamellar keratitis (NSDIK). Setting T.L.C. The Laser Center, Brea, California, USA. Methods This prospective study included 2 cohort groups, each consisting of 105 consecutive eyes treated with laser in situ keratomileusis (LASIK) for myopia and astigmatism. Group A received the standard LASIK medication protocol and Group B, an additional drop of prednisolone sodium phosphate 1% solution on the undersurface of the cap immediately after it was reflected, prior to initiating the laser treatment. After the laser treatment was completed, the flap was repositioned; 1 minute after the steroid application, the interface was irrigated. All patients were examined postoperatively and placed in 1 of 4 categories: no interface keratitis, grade 1 (mild), grade 2 (moderate with decreased vision), or grade 3 (severe with decreased vision). Results The incidence of NSDIK in Group A was 17.1% (18 eyes); 14 eyes (78.0%) were grade 1 and 4 (22.0%), grade 2. The incidence in Group B was 6.7% (7 eyes); all eyes were grade 1. Topical intrastromal steroid application significantly reduced the incidence and severity of NSDIK ( P Conclusion We propose that intraoperative intrastromal steroid application is a safe and effective way to reduce the incidence and severity of NSDIK.

Chemokines induce chemotaxis of hematopoietic progenitor cells (HPC), and suppress their proliferation. In this study we report that SLC/Exodus2/6Ckine/TCA4 (hereafter termed SLC) is a chemoattractant for human CD34+ HPC. SLC mainly induces preferential chemotaxis of macrophage progenitors. We examined the chemotactic activity of CXCR3 ligands on CD34+ HPC because it has been reported that SLC is a potential ligand of CXC chemokine receptor, CXCR3, in addition to a CC chemokine receptor, CCR7. It was found that the CXCR3 ligands, MIG and interferon-γ inducible protein-10 (IP-10), unlike SLC, did not induce chemotaxis of CD34+ HPC. In this regard, CCR7 ligands (SLC and CKβ-11), but not IP-10 and MIG, induce actin polymerization in CD34+ cells. On the other hand, CCR7 ligands and CXCR3 ligands, but not the CXCR4 ligand SDF-1, showed inhibitory activity for proliferation of myeloid progenitor cells. Our results suggest that SLC is a potential trafficking factor for HPC, and that chemokines that bind CCR7, CXCR4, and CXCR3 have differential biological activities on HPC in terms of suppression and chemotaxis. J. Leukoc. Biol. 66: 455–461; 1999.

Chemokines are a family of related proteins that regulate leukocyte infiltration into inflamed tissue and play important roles in many disease processes. Chemokines are divided into two major groups, CC or CXC, based on their sequence around the amino terminal cysteines. We report here, the isolation of a novel murine CC chemokine termed ALP for its amino terminal peptide sequence. This novel chemokine is distantly related to other CC chemokines (37% identity with murine Exodus-1/LARC/Mip-3alpha), but has a unique carboxy terminal extension. It is expressed preferentially in testis, heart, and liver, which is atypical for CC chemokines.

Two human CC chemokines, SLC/6Ckine/Exodus2/TCA4 and CKbeta-11/MIP-3beta/ELC, are previously reported as efficacious chemoattractants for T- and B-cells and dendritic cells. SLC and CKbeta-11 share only 32% amino acid identity, but are ligands for the same chemokine receptor, CCR7. In this study, we examined chemotactic activity of SLC and CKbeta-11 for NK cells and lymphoid progenitors in bone marrow and thymus. It was found that these two CCR7 ligands are chemoattractants for neonatal cord blood and adult peripheral blood NK cells and cell lines. SLC and CKbeta-11 preferentially attract the CD56(+)CD16(-) NK cell subset over CD56(+)CD16(+) NK cells. SLC and CKbeta-11 also demonstrate selective chemotactic activity on late stage CD34(-)CD19(+)IgM- B-cell progenitors and CD4(+) and CD8(+) single-positive thymocytes, but not early stage progenitors. It was noted that SLC is an efficient desensitizer of CKbeta-11-dependent NK cell chemotaxis, while CKbeta-11 is a weak desensitizer of SLC-dependent chemotaxis. Taken together, these results suggest that SLC and CKbeta-11 have the potential to control trafficking of NK cell subsets and late stage lymphoid progenitors in bone marrow and thymus.

Chemokines are a family of related proteins that regulate leukocyte infiltration into inflamed tissue and play important roles in many disease processes. Chemokines are divided into two major groups, CC or CXC, based on their sequence around the amino terminal cysteines. We report the PCR cloning of a novel human chemokine termed BRAK for its initial isolation from breast and kidney cells. This novel chemokine is distantly related to other CXC chemokines (30% identity with MIP-2alpha and beta) and shares several biological activities. BRAK is expressed ubiquitously and highly in normal tissue. However, it was expressed in only 2 of 18 cancer cell lines. BRAK is located on human chromosome 5q31.

Taurine is an abundant amino acid in inflammatory cells, where it acts as a trap for toxic hypochlorous acid (HOCl/OCl−) and protects tissue from damage resulting from overt inflammatory reactions as demonstrated in vivo and in vitro models of inflammation7,10,11. High concentrations of taurine are present in the cytosol of leukocytes (20–50 mM)4,8. Under physiological conditions the formation of taurine chloramine (Tau-Cl) is catalyzed by a reaction of the polymorphonuclear leukocytes (PMN) derived from myeloperoxidase (MPO) and hypochlorous acid with taurine. Formation of Tau-Cl may also be catalyzed directly by a halide-dependent myeloperoxidase reaction not involving formation of HOCl/OCl−. Although Tau-Cl inherently possesses oxidative potential, it is more stable and less toxic than HOCl. The addition of exogenous taurine strongly enhances chloramine formation. Tau-Cl plays a role in inflammation by inhibiting the production of nitric oxide, TNF-α, IL-1, IL-6, IL-8 and prostaglandin E2 in macrophages and production of superoxide anion (O2−) in PMN7,10,11,12

Codon bias has been observed in many species. The usage of selective codons in a given gene is positively correlated with its expression efficiency. As an experimental approach to study codon-usage effects on heterologous gene expression in mammalian cells, we designed two human erythropoietin (EPO) genes, one in which native codons were systematically substituted with codons frequently found in highly expressed human genes and the other with codons prevalent in yeast genes. Relative performances of the re-engineered EPO genes were evaluated with various combinations of promoters and signal leader sequences. Under the comparable set of combinations, mature EPO gene with human high-frequency codons gave a considerably higher level of expression than that with yeast high-frequency codons. However, the levels of EPO expression varied, depending on the alternate combinations. Since the promoters and the signal leader sequences that we used are known to be equally efficient in gene expression, we hypothesized that the varied expression levels were due to the linear sequence between the promoter and the coding gene sequence. To test this possibility, we designed the EPO gene with hybrid codon usage in which the 5'-proximal region of the EPO gene was synthesized with yeast-biased codons and the rest with human-biased codons. This codon-usage hybrid EPO gene substantially enhanced the level of EPO transcripts and proteins up to 2.9-fold and 13.8-fold, respectively, when compared to the level reached by the original counterpart. Our results suggest that the linear sequence between the promoter and the 5'-proximal region of a gene plays an important role in achieving high-level expression in mammalian cells.

Little is known regarding movement of stem or myeloid progenitor cells. Chemokines implicated in chemotaxis of myeloid progenitors include stromal derived factor (SDF)-1 and CC chemokines CKβ-11/MIP-3β /EBI1-ligand/Exodus-3 and SLC/6Ckine/TCA4/Exodus-2. SDF-1 chemotaxes CFU-GM, CFU-G, CFU-M, BFU-E, CFU-GEMM, and earlier cells. We have shown that CKβ-11 and SLC preferentially chemotax M-CSF-responsive CFU-M (Kim et al. J Immunol 161:2580,1998; J. Leuk Biol 66:455,1999). To evaluate in vivo activities of CKβ-11, we produced transgenic mice in which the CKβ-11 gene, under an LCK promoter, was over-expressed in lymphoid tissue such as spleen. CFU-GM, BFU-E and CFU-GEMM, responsive in vitro to stimulation with a combination, of growth factors were evaluated for absolute numbers and cycling status in marrow and spleen. While small non-significant decreases were noted in numbers of these progenitors in marrow of transgenic compared to littermate control mice, CFU-GM-type progenitor numbers were significantly increased in spleens of the transgenic mice. These splenic CFU-GM were in rapid cycle (47 ± 2% S-phase) compared to controls (0% S-phase). Splenic BFU-E and CFU-GEMM numbers and cycling status (0% S-phase) were unchanged. To more precisely define the type of progenitor increased in the spleen of CKβ-11 transgenics we evaluated M-CSF-responsive macrophage progenitors (CFU-M) and GM-CSF-responsive CFU-GM. CFU-M, but not CFU-GM, numbers were significantly increased in spleens of CKβ-11 transgenic mice and CFU-M were in rapid cycle (63% S-phase) compared to control mice (0% S-phase). This correlated with a small decrease (20%) in CFU-M levels in the transgenic marrow. Notably, CFU-M in marrow of transgenic mice were in slow cycle (2 ± 2% S-phase) compared to control marrow (34 ± 4% S-phase). These results show that tissue-specific expression of CKβ-11 is coincident with enhanced levels of cycling macrophage progenitors, perhaps through preferential attraction of cycling CFU-M.

Background & Aims Retinoic acid plays a positive role in induction of FoxP3 + regulatory T cells. Because retinoic acid is produced as a metabolite of vitamin A in the intestine and FoxP3 + T cells regulate intestinal inflammation, we investigated the impact of vitamin A status on the regulatory T cells and inflammation in the intestine. Methods The SAMP1/YP model is a mouse model of Crohn's disease. We made vitamin A–deficient, vitamin A–excessive, and normal SAMP1/YP mice and assessed the intestinal inflammation. We also investigated the phenotype and function of FoxP3 + T cells induced in different levels of vitamin A availability in regulation of intestinal inflammation in a T-cell–induced inflammation model in SCID mice. Results The limited and excessive vitamin A conditions induced distinct FoxP3 + T-cell subsets in vivo, and both ameliorated the intestinal inflammation in SAMP1/YP mice. The limited vitamin A condition greatly induced unusual CD103 + CCR7 + FoxP3 + cells, while the high vitamin A condition induced CCR9 + α4β7 + FoxP3 + T cells in the intestine. Both FoxP3 + T-cell populations, when transferred into mice with ongoing intestinal inflammation, were highly effective in reversing the inflammation. Blockade or lack of occupancy of RARα is a mechanism to induce highly suppressive CD103 + CCR7 + FoxP3 + cells in both the thymus and periphery in limited vitamin A availability. Conclusions Our results identify novel pathways of inducing highly suppressive FoxP3 + regulatory T cells that can effectively control intestinal inflammation. The results have significant ramifications in treating inflammatory bowel diseases.

T helper cells that produce IL-17 (Th17 cells) play important roles in regulation of immunity to bacteria and fungi and can cause organ-specific inflammation. The intestine is a tissue where Th17 cells are highly enriched, but migration and trafficking receptors of Th17 cells to the intestine have been unclear. It has been established that CCR6 is the signature chemokine receptor for Th17 cells but the role of this trafficking receptor in Th17 cell trafficking to the intestine has not been determined. We report here that Th17 cells preferentially migrate to the intestine and associated-lymphoid tissues, and CCR6 is the homing receptor important for Th17 cell migration to certain tissue microenvironments of the intestine where its ligand CCL20 is highly expressed. We determined the function of CCR6 of Th17 cells by comparing the migration and effector function of Th17 cells derived from wild type and CCR6-deficient mice. CCR6-deficient Th17 cells were defective in migration to Peyer's patches and small intestine but their migration to the large intestine was normal. Surprisingly, administration of CCR6-deficient Th17 cells into severe combined immunodeficiency (SCID) mice led to excessive intestinal inflammation. Following the administration of Th17 cells, we found that Th17 cells fail to propagate in the gut in the absence of CCR6 and transdifferentiate into inflammatory Th1 cells. In addition, CCR6 deficiency led to aberrantly wide-spread effector T cells in the inflamed intestine of the SCID mice. Finally, we found that the expression of CCR6 by Th17 cells is induced by TGF-β1 but suppressed by IL-2 in vitro and in vivo. Taken together, we conclude that CCR6 is a key trafficking receptor that regulates the migration and effector function of Th17 cells in the intestine.

This work was supported by the WCU program through KOSEF funded by the Ministry of Education, Science and Technology (no. 400-2008-0230). The authors also acknowledge the Research Center for Energy Conversion and Storage for financial support.

To study the effect of binocular rivalry (BR) suppression on the ocular following response (OFR), we recorded the OFR in both the suppressed and dominant phases of BR. The BR was established using stationary horizontal/vertical grating patterns presented on two PC monitors. Once a subjective image of a vertical or horizontal grating pattern was perceived, subjects pressed a button to trigger an onset of brief horizontal movement (750 ms) of the vertical grating pattern and an offset of the horizontal pattern. The OFRs were recorded using a scleral search coil system at 1 KHz. The OFRs from the suppressed phases were significantly reduced compared to those from the dominant phases. The OFRs were asymmetrical to temporalward and nasalward motion in most conditions. We suggest that asymmetry of OFRs under the incomplete BR conditions may be a reflection of imbalance binocular inputs and processing in the visual system similar to asymmetrical optokinetic nystagmus in strabismic subjects. The latency of the OFR in deeper suppressed conditions was prolonged, suggesting that the interaction of BR and the OFR may occur at multiple stages including an early stage of the visual processing. The OFR may have the potential for objective measurement of BR suppression in clinical evaluation of binocular function.

This work was supported by the Korean Science and Engineering Foundation via the Research Centre for Energy Conversion and Storage.

FoxP3+ regulatory T cells play important roles in immune regulation and tolerance. There is an increasing body of evidence that the migration ability of FoxP3+ T cells is important for their regulatory functions at effector tissue sites. We investigated the two different trafficking receptor switches of FoxP3+ T cells occurring in the thymus and secondary lymphoid tissues. The first trafficking receptor switch in the thymus is developmentally programmed: Precursors of FoxP3+ cells undergo the first trafficking receptor switch from CCR8/CCR9 to CXCR4 and then finally to CCR7, generating mostly homogeneous CD62L+CCR7+ FoxP3+ T cells. The recent thymic emigrant CD62L+CCR7+ FoxP3+ T cells are programmed to migrate to secondary lymphoid tissues. The CD62L+CCR7+ FoxP3+ T cells undergo the second switch in trafficking receptors in an antigen-dependent manner. This second switch involves down-regulation of CCR7 and CXCR4 but up-regulation of a number of memory/effector type homing receptors, resulting in generation of heterogeneous FoxP3+ T cell subsets expressing various combinations of trafficking receptors including CCR2, CCR4, CCR5, CCR6, CCR7, CCR8, CCR9 and CXCR5. FoxP3+ cells undergo the second switch to selected non-lymphoid tissue homing receptors at highly accelerated rates. This results in generation of FoxP3+ T cells with unconventionally efficient migratory capacity to major non-lymphoid tissues such as intestinal lamina propria and bone marrow. Importantly, this accelerated switch of FoxP3+ T cells is conserved in both men and mice. The two switches in homing receptors are though to be important for effective distribution and differentiation-dependent effector functions of FoxP3+ regulatory T cells.

4-1BB(CD137) is a member of the tumor necrosis factor receptor superfamily and is expressed on avtivated T cells, monocytes and natural killer (NK) cells. The expression of 4-1BB has been known to be activation dependent except regulatory T cells. Interestingly, we found that 4-1BB has three promoter regions which could regulate 4-1BB mRNA level. Thus, we investigated expression level of three different transcripts of 4-1BB in naïve T cells and EL4 cell lines. It was reported that 4-1BB expresson was increased by several anti-cancer drugs in human peripheral blood mononuclear cells and CEM cells. We also test whether the treatment with anti-cancer drugs could induce 4-1BB expression in naïve T cells and EL4 cells. The data indicated that 4-1BB expression increased by agents such as mitomycin C, 5-FU, and doxorubicin. Especially, type II transcript of 4-1BB was preferentially induced in naïve T cells stimulated by anti-CD3 because of NFkB binding site in type II promoter region. It suggests that type II promoter region is major promoter which could be activated in naïve T cells by TCR signaling. We also found a splicing variant deleted exon 7 including transmembrane domain region could inhibit the 4-1BB signaling. Our studies demonstrated that 4-1BB has three promoter could induce the expression of 4-1BB mRNA but the type II promoter is a inducible promoter in naïve T cell and costimulatory effect through 4-1BB receptor could be modulated by soluble 4-1BB produced by splicing variant without transmembrane domain induced in activation of naïve T cells.

Background The function of CD57+ CD4+ T cells, constituting a major subset of germinal center T (GC-Th) cells in human lymphoid tissues, has been unclear. There have been contradictory reports regarding the B cell helping function of CD57+ GC-Th cells in production of immunoglobulin (Ig). Furthermore, the cytokine and co-stimulation requirement for their helper activity remains largely unknown. To clarify and gain more insight into their function in helping B cells, we systematically investigated the capacity of human tonsil CD57+ GC-Th cells in inducing B cell Ig synthesis.

How Tregs migrate to GCs, and whether they regulate the helper activity of the T cells in GCs (GC-Th cells) remains poorly understood. We found a T cell subset in human tonsils that displays potent suppressive activities toward GC-Th cell–dependent B cell responses. These Tregs with the surface phenotype of CD4+CD25+CD69– migrate well to CCL19, a chemokine expressed in the T cell zone, but poorly to CXCL13, a chemokine expressed in the B cell zone. This migration toward the T cell–rich zone rapidly changes to trafficking toward B cell follicles upon T cell activation. This change in chemotactic behavior upon activation of T cells is consistent with their switch in the expression of the 2 chemokine receptors CXCR5 and CCR7. CD4+CD25+CD69– Tregs suppress GC-Th cells and GC-Th cell–induced B cell responses such as Ig production, survival, and expression of activation-induced cytosine deaminase. Our results have identified a subset of Tregs that is physiologically relevant to GC-Th cell–dependent B cell responses and a potential regulation mechanism for the trafficking of these Tregs to GCs.

In vitro activity of cefpimizole, an experimental third generation cephalosporin, and 10 other antimicrobials (ampicillin, azlocillin, cefamandole, cefoperazone, cefotaxime, mezlocillin, moxalactam, piperacillin, rifampin and sulfamethoxazole/trimethoprim) were determined for 181 isolates of Haemophilus obtained from pediatric patients. For 156 β-lactamase-negative isolates, MIC50 values of cefoperazone, cefpimizole, and cefamandole were 4, 8, and 16 times greater than those of moxalactam and cefotaxime (0.06 μg/ml). 25 β-lactamase-producing isolates were resistant to ampicillin, azlocillin, mezlocillin, and piperacillin, however, MIC50 of all third generation cephalosporin were similar to those obtained for β-lactamase-negative organisms. Refampin and SMX/TMP demonstrated low MIC50 values for all isolates.

Growth of bacterial and fungal organisms in i.v. fat emulsions was studied. A total of 81 isolates of 15 bacterial and fungal strains were used to inoculate (in test tubes) 10% soybean oil emulsion (Intralipid, Cutter Laboratories), 10% safflower oil emulsion (Liposyn, Abbott Laboratories), trypticase soya broth, and 0.9% sodium chloride at about 2500 organisms/ml. Duplicate samples and negative controls were prepared. Samples were handled under two procedures after inoculation: (1) initially refrigerated overnight, then stored at room temperature for 24 hours, and (2) stored only at room temperature for 24 hours. Samples were taken at 3, 7, and 24 hours after the samples were placed at room temperature, and colony counts were performed. Most organisms grew equally well in the fat emulsions and trypticase soya broth. Fungal strains grew more slowly than bacterial strains but reached equal numbers by 24 hours. Organisms grew quite slowly in sodium chloride, and negative controls showed no growth. These i.v. fat emulsions supported bacterial and fungal growth at the same level as trypticase soya broth.

The techniques of fluorescent antibody (FA) and counterimmunoelectrophoresis (CIE) were compared with the Neufeld test (quellung reaction) for typing of Streptococcus pneumoniae. A total of 88 isolates were examined by these three methods. Pool-, type-, or group-specific pneumococcal antisera were used in all three methods. Each isolate was initially tested with polyvalent antisera and all of the nine pools of antisera. Selection of the type- or group-specific antisera depended upon the reaction of the isolate with the pool sera. Sixty-eight of 88 (77.3%) isolates were positive using pool or typing sera and were correctly typed by CIE, while FA was found to be accurate for only 61 of 88 (69.3%) isolates. Positive reactions with more than one pool- or type-specific antisera, or no reaction, were seen with several of the isolates with both techniques. Even though CIE and FA are rapid and simple techniques, microbiologists should be cautious when utilizing them for typing of S. pneumoniae because of the discrepancies observed in this study.