Murine B Cell Development and Antibody Responses to Model Antigens Are Not Impaired in the Absence of the TNF Receptor GITR

The Glucocorticoid-Induced Tumor necrosis factor Receptor GITR, a member of the tumor necrosis factor receptor superfamily, has been shown to be important in modulating immune responses in the context of T cell immunity. B lymphocytes also express GITR, but a role of GITR in humoral immunity has not been fully explored. To address this question, we performed studies to determine the kinetics of GITR expression on naïve and stimulated B cells and the capacity of B cells to develop and mount antibody responses in GITR−/− mice. Results of our studies indicate that all mature B cells express GITR on the cell surface, albeit at different levels. Expression of GITR on naïve mature B cells is upregulated by BCR signaling, but is counteracted by helper T cell-related factors and other inflammatory signals in vitro. In line with these findings, expression of GITR on germinal center and memory B cells is lower than that on naïve B cells. However, the expression of GITR is strongly upregulated in plasma cells. Despite these differences in GITR expression, the absence of GITR has no effect on T cell-dependent and T cell-independent antibody responses to model antigens in GITR−/− mice, or on B cell activation and proliferation in vitro. GITR deficiency manifests only with a slight reduction of mature B cell numbers and increased turnover of naïve B cells, suggesting that GITR slightly contributes to mature B cell homeostasis. Overall, our data indicate that GITR does not play a significant role in B cell development and antibody responses to T-dependent and independent model antigens within the context of a GITR-deficient genetic background

Magnetic resonance imaging and morphometric histologic analysis of prostate tissue composition in predicting the clinical outcome of terazosin therapy in benign prostatic hyperplasia

Purpose: To determine whether magnetic resonance imaging (MRI) or quantitative color-imaged morphometric analysis (MA) of the prostate gland are related to the clinical response to terazosin. Methods: Thirty-six male patients with symptomatic benign prostatic hyperplasia (BPH) with a serum prostate-specific antigen level of 4-10 ng/mL underwent MRI with body coil, transrectal prostate ultrasonography and biopsy prior to terazosin therapy. For MRI-determined stromal and non-stromal BPH, the ratio of the signal intensity of the inner gland to the obturator internus muscle was evaluated. Histologic sections were stained with hematoxylin and eosin. The MA of the specimens was performed by Samba 2000. Results of the two techniques were interpreted according to the terazosin therapy results. Results: The mean stromal percentage was 60.5 ± 18.0%. No statistically significant relationship was found between the clinical outcome of terazosin and the MRI findings. The MA results showed a significant relationship between the percentage of stroma and the percent change of the peak urinary flow rate, but not with the percent change of the international prostate symptom score after terazosin therapy (P < 0.05). Conclusion: Magnetic resonance imaging alone is not sufficient in predicting the response to terazosin therapy. Morphometric analysis of BPH tissue composition can be used in predicting the clinical outcome of terazosin therapy but it is suitable only in patients for whom prostatic biopsy is necessary in order to rule out prostate cancer

Expression hierarchy of T cell epitopes from melanoma differentiation antigens: unexpected high level presentation of tyrosinase-HLA-A2 Complexes revealed by peptide-specific, MHC-restricted, TCR-like antibodies.

Peptide Ags presented by class I MHC molecules on human melanomas and that are recognized by CD8(+) T cells are the subjects of many studies of antitumor immunity and represent attractive candidates for therapeutic approaches. However, no direct quantitative measurements exist to reveal their expression hierarchy on the cell surface. Using novel recombinant Abs which bind these Ags with a peptide-specific, MHC-restricted manner, we demonstrate a defined pattern of expression hierarchy of peptide-HLA-A2 complexes derived from three major differentiation Ags: gp100, Melan-A/Mart-1, and tyrosinase. Studying melanoma cell lines derived from multiple patients, we reveal a surprisingly high level of presentation of tyrosinase-derived complexes and moderate to very low expression of complexes derived from other Ags. No correlation between Ag presentation and mRNA expression was found; however, protein stability may play a major role. These results provide new insights into the characteristics of Ag presentation and are particularly important when such targets are being considered for immunotherapy. These results may shed new light on relationships between Ag presentation and immune response to cancer Ags

Minimally Invasive Mandibular Microsurgery: A Systematic Review and Meta-analysis

Background:. Microsurgical advances have led to minimally invasive approaches for mandibular reconstruction. Currently, no resource compares all minimally invasive microvascular mandibular reconstruction (MIMMR) treatment options. Methods:. All known cases of MIMMR were identified following the Preferred Reporting Items for Systematic Reviews, Meta-Analyses guidelines, and our own surgical experience. Patient demographics, MIMMR type [submandibular (SM), modified facelift/retroauricular (MFL/RA), or intraoral (IO)], methodology, and clinical outcomes were analyzed with the Fisher exact and Kruskal-Wallis tests. Results:. Forty-seven patients underwent MIMMR. Ameloblastoma was the most common pathology treated using all approaches, and MFL/RA was the only approach used to treat squamous cell carcinoma (P = 0.0103). Reconstruction was reported for large, bilateral defects only via the SM or IO approach (P = 0.0216). The iliac crest or fibula was used as a donor site. The facial artery was the most common recipient vessel using the IO and SM approaches, whereas the superior thyroid and external carotid vessels were the most common in the MFL/RA approach (P < 0.0001). Virtual planning was used in all cases performed via an IO approach, 80.0% of cases using an SM approach, and no MFL/RA cases (P < 0.0001). Good aesthetic and functional outcomes were reported for every patient, and there was no difference in complication rates (P = 0.2880). Conclusions:. Minimally invasive approaches are safe and effective treatment options for patients requiring mandibular microsurgery, usually in the setting of benign pathology. The IO and SM approaches usually rely on the facial vessels, whereas the MFL/RA approach permits access to the superior thyroid and external carotid vessels and cervical lymphadenectomy

Efficient optogenetic silencing of neurotransmitter release with a mosquito rhodopsin

Information is carried between brain regions through neurotransmitter release from axonal presynaptic terminals. Understanding the functional roles of defined neuronal projection pathways requires temporally precise manipulation of their activity. However, existing inhibitory optogenetic tools have low efficacy and off-target effects when applied to presynaptic terminals, while chemogenetic tools are difficult to control in space and time. Here, we show that a targeting-enhanced mosquito homolog of the vertebrate encephalopsin (eOPN3) can effectively suppress synaptic transmission through the G(i/o) signaling pathway. Brief illumination of presynaptic terminals expressing eOPN3 triggers a lasting suppression of synaptic output that recovers spontaneously within minutes in vitro and in vivo. In freely moving mice, eOPN3-mediated suppression of dopaminergic nigrostriatal afferents induces a reversible ipsiversive rotational bias. We conclude that eOPN3 can be used to selectively suppress neurotransmitter release at presynaptic terminals with high spatiotemporal precision, opening new avenues for functional interrogation of long-range neuronal circuits in vivo

Optogenetic silencing of neurotransmitter release with a naturally occurring invertebrate rhodopsin

Information is carried between brain regions through neurotransmitter release from axonal presynaptic terminals. Understanding the functional roles of defined neuronal projection pathways in cognitive and behavioral processes requires temporally precise manipulation of their activity in vivo. However, existing optogenetic tools have low efficacy and off-target effects when applied to presynaptic terminals, while chemogenetic tools are difficult to control in space and time. Here, we show that a targeting-enhanced mosquito homologue of the vertebrate encephalopsin (eOPN3) can effectively suppress synaptic transmission through the G(i/o) signaling pathway. Brief illumination of presynaptic terminals expressing eOPN3 triggers a lasting suppression of synaptic output that recovers spontaneously within minutes in vitro as well as in vivo. In freely moving mice, eOPN3-mediated suppression of dopaminergic nigrostriatal afferents leads to an ipsiversive rotational bias. We conclude that eOPN3 can be used to selectively suppress neurotransmitter release at synaptic terminals with high spatiotemporal precision, opening new avenues for functional interrogation of long-range neuronal circuits in vivo