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C Moratz

Publications and source records attributed to C Moratz.

4 recordsLinked to original sources
PubMed2000

Regulator of G protein signaling 1 (RGS1) markedly impairs Gi alpha signaling responses of B lymphocytes.

Regulator of G protein signaling (RGS) proteins modulate signaling through pathways that use heterotrimeric G proteins as transducing elements. RGS1 is expressed at high levels in certain B cell lines and can be induced in normal B cells by treatment with TNF-alpha. To determine the signaling pathways that RGS1 may regulate, we examined the specificity of RGS1 for various G alpha subunits and assessed its effect on chemokine signaling. G protein binding and GTPase assays revealed that RGS1 is a Gi alpha and Gq alpha GTPase-activating protein and a potential G12 alpha effector antagonist. Functional studies demonstrated that RGS1 impairs platelet activating factor-mediated increases in intracellular Ca+2, stromal-derived factor-1-induced cell migration, and the induction of downstream signaling by a constitutively active form of G12 alpha. Furthermore, germinal center B lymphocytes, which are refractory to stromal-derived factor-1-triggered migration, express high levels of RGS1. These results indicate that RGS proteins can profoundly effect the directed migration of lymphoid cells.

Animals↗
PubMed1997

B cell development in mice.

The development and establishment of the B Cell Repertoire is the net result of both genetic and environmental forces. The primary event at the genetic level is Ig gene rearrangement resulting in numerous possible combination of genes which can be further modified by somatic events such as N segment addition and somatic mutation. Environmental forces in the form of self and exogenous Ags also shape the repertoire by positively or negatively selecting B cells according to the specificity of their Ig receptors. These are dynamic processes beginning with the earliest expression of immunoglobulins in fetal life and continuing throughout life. In this review we discuss the genetic and selective mechanisms responsible for differences in the early immune system compared to that of the adult.

Animals↗
PubMed1992

Two antigens detected on human ocular melanomas with the mouse monoclonal antibodies 2/10SN and 10/12SN.

Seven human ocular melanoma cell lines were established in vitro and 3 of these, GU-4, LLN-40 and its subline C17-11, were characterized. Mice were immunized with these ocular melanoma cell lines, and 2 hybridomas producing monoclonal IgG1 antibodies (MAb) were produced. MAb 2/10SN recognizes a 44-kDa monomeric protein, whereas MAb 10/12SN reacts with an 83/65-kDa heterodimeric protein. These melanoma-associated antigens (MAA) are detected at high concentrations in the cytoplasm of ocular melanoma cells. However, cell-surface labelling techniques suggest that these MAA are also associated with the cell-surface membrane. These 2 ocular MAA are also expressed by several skin melanoma cell lines. Immunohistochemical studies have localized these antigens to ocular and skin melanomas, to sweat ducts and basal squamous cells in normal skin, with limited expression in several other normal tissues and some carcinomas. Biodistribution studies in nude mice with human ocular melanomas have demonstrated good localization of 125I-labeled MAb 2/10SN at the tumor sites. Therefore, these 2 MAbs, 2/10SN and 10/12SN, recognize MAA which appear to be unique and may prove useful for imaging purposes.

Animals↗