Embryonic and adult chick haemoglobins: Their reaction with p-chloromercury benzoate

At least one of the primitive embryonic hemoglobins (Hbs) dissociates into monomers after treatment with p-chloromercury benzoate. The other primitive embryonic Hbs as well as the definitive embryonic and the adult Hbs are probably dissociated, by this reagent, into dimers. A globin from a primitive embryonic Hb component, which can be completely dissociated by this agent, may be isolated by gel filtration on Sephadex.     

Vaccine-Induced Boosting of Influenza Virus-Specific CD4 T Cells in Younger and Aged Humans

Current yearly influenza virus vaccines induce strain-specific neutralizing antibody (NAb) responses providing protective immunity to closely matched viruses. However, these vaccines are often poorly effective in high-risk groups such as the elderly and challenges exist in predicting yearly or emerging pandemic influenza virus strains to include in the vaccines. Thus, there has been considerable emphasis on understanding broadly protective immunological mechanisms for influenza virus. Recent studies have implicated memory CD4 T cells in heterotypic immunity in animal models and in human challenge studies. Here we examined how influenza virus vaccination boosted CD4 T cell responses in younger versus aged humans. Our results demonstrate that while the magnitude of the vaccine-induced CD4 T cell response and number of subjects responding on day 7 did not differ between younger and aged subjects, fewer aged subjects had peak responses on day 14. While CD4 T cell responses were inefficiently boosted against NA, both HA and especially nucleocaspid protein- and matrix-(NP+M) specific responses were robustly boosted. Pre-existing CD4 T cell responses were associated with more robust responses to influenza virus NP+M, but not H1 or H3. Finally pre-existing strain-specific NAb decreased the boosting of CD4 T cell responses. Thus, accumulation of pre-existing influenza virus-specific immunity in the form of NAb and cross-reactive T cells to conserved virus proteins (e.g. NP and M) over a lifetime of exposure to infection and vaccination may influence vaccine-induced CD4 T cell responses in the aged.     

Metabotropic Glutamate Receptor 1 Expression and Its Polymorphic Variants Associate with Breast Cancer Phenotypes

Several epidemiological studies have suggested a link between melanoma and breast cancer. Metabotropic glutamate receptor 1 (GRM1), which is involved in many cellular processes including proliferation and differentiation, has been implicated in melanomagenesis, with ectopic expression of GRM1 causing malignant transformation of melanocytes. This study was undertaken to evaluate GRM1 expression and polymorphic variants in GRM1 for associations with breast cancer phenotypes. Three single nucleotide polymorphisms (SNPs) in GRM1 were evaluated for associations with breast cancer clinicopathologic variables. GRM1 expression was evaluated in human normal and cancerous breast tissue and for in vitro response to hormonal manipulation. Genotyping was performed on genomic DNA from over 1,000 breast cancer patients. Rs6923492 and rs362962 genotypes associated with age at diagnosis that was highly dependent upon the breast cancer molecular phenotype. The rs362962 TT genotype also associated with risk of estrogen receptor or progesterone receptor positive breast cancer. In vitro analysis showed increased GRM1 expression in breast cancer cells treated with estrogen or the combination of estrogen and progesterone, but reduced GRM1 expression with tamoxifen treatment. Evaluation of GRM1 expression in human breast tumor specimens demonstrated significant correlations between GRM1 staining with tissue type and molecular features. Furthermore, analysis of gene expression data from primary breast tumors showed that high GRM1 expression correlated with a shorter distant metastasis-free survival as compared to low GRM1 expression in tamoxifen-treated patients. Additionally, induced knockdown of GRM1 in an estrogen receptor positive breast cancer cell line correlated with reduced cell proliferation. Taken together, these findings suggest a functional role for GRM1 in breast cancer.     

Altered Expression Pattern of Molecular Factors Involved in Colonic Smooth Muscle Functions: An Immunohistochemical Study in Patients with Diverticular Disease

Background

The pathogenesis of diverticular disease (DD) is thought to result from complex interactions among dietary habits, genetic factors and coexistence of other bowel abnormalities. These conditions lead to alterations in colonic pressure and motility, facilitating the formation of diverticula. Although electrophysiological studies on smooth muscle cells (SMCs) have investigated colonic motor dysfunctions, scarce attention has been paid to their molecular abnormalities, and data on SMCs in DD are lacking. Accordingly, the main purpose of this study was to evaluate the expression patterns of molecular factors involved in the contractile functions of SMCs in the tunica muscularis of colonic specimens from patients with DD.

Methods and Findings

By means of immunohistochemistry and image analysis, we examined the expression of Cx26 and Cx43, which are prominent components of gap junctions in human colonic SMCs, as well as pS368-Cx43, PKCps, RhoA and αSMA, all known to regulate the functions of gap junctions and the contractile activity of SMCs.The immunohistochemical analysis revealed significant abnormalities in DD samples, concerning both the expression and distribution patterns of most of the investigated molecular factors.

Conclusion

This study demonstrates, for the first time, that an altered pattern of factors involved in SMC contractility is present at level of the tunica muscularis of DD patients. Moreover, considering that our analysis was conducted on colonic tissues not directly affected by diverticular lesions or inflammatory reactions, it is conceivable that these molecular alterations may precede and predispose to the formation of diverticula, rather than being mere consequences of the disease.     

An integrated assessment of histopathological changes of the enteric neuromuscular compartment in experimental colitis

Bowel inflammatory fibrosis has been largely investigated, but an integrated assessment of remodelling in inflamed colon is lacking. This study evaluated tissue and cellular changes occurring in colonic wall upon induction of colitis, with a focus on neuromuscular compartment. Colitis was elicited in rats by 2,4‐dinitrobenzenesulfonic acid (DNBS). After 6 and 21 days, the following parameters were assessed on paraffin sections from colonic samples: tissue injury and inflammatory infiltration by histology; collagen and elastic fibres by histochemistry; HuC/D, glial fibrillar acidic protein (GFAP), proliferating cell nuclear antigen (PCNA), nestin, substance P (SP), von Willebrand factor, c‐Kit and transmembrane 16A/Anoctamin1 (TMEM16A/ANO1) by immunohistochemistry. TMEM16A/ANO1 was also examined in isolated colonic smooth muscle cells (ICSMCs). On day 6, inflammatory alterations and fibrosis were present in DNBS‐treated rats; colonic wall thickening and fibrotic remodelling were evident on day 21. Colitis was associated with both an increase in collagen fibres and a decrease in elastic fibres. Moreover, the neuromuscular compartment of inflamed colon displayed a significant decrease in neuron density and increase in GFAP/PCNA‐positive glia of myenteric ganglia, enhanced expression of neural SP, blood vessel remodelling, reduced c‐Kit‐ and TMEM16A/ANO1‐positive interstitial cells of Cajal (ICCs), as well as an increase in TMEM16A/ANO1 expression in muscle tissues and ICSMCs. The present findings provide an integrated view of the inflammatory and fibrotic processes occurring in the colonic neuromuscular compartment of rats with DNBS‐induced colitis. These morphological alterations may represent a suitable basis for understanding early pathophysiological events related to bowel inflammatory fibrosis.     

Shp2 in PC12 cells: NGF versus EGF signalling

The balance between specific signals from different growth factors dictates the biological response of mammalian cells including cell proliferation, differentiation and survival. PC12 cells represent a model of choice to compare the signalling of differentiative growth factors, as NGF, and of mitogenic growth factors, as EGF. In these cells the prolonged activity of the ERK kinase dictates the decision of cells to differentiate. Here we focused on the cytosolic tyrosine phosphatase Shp2 as an established regulator of the Ras-ERK cascade, to elucidate its involvement in determining the stimulation-dependent PC12 cell fate. To this end, we generated PC12 derived cell lines that express the interfering mutant of Shp2 under a tetracycline-inducible promoter. Our findings show that Shp2 participates to the opposite effects induced in PC12 cells by EGF and NGF and that the interactions with the multidocking Gab2 protein mediate such effects.