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F Grosveld

Publications and source records attributed to F Grosveld.

184 records · Page 11Linked to original sources

The structure of a thirty-six kilobase region of the human chromosome including the fibroblast interferon gene IFN-beta.

The isolation of a human genomic cosmid hybrid containing the interferon beta gene has recently been reported (Gross et al., 1981). This hybrid was mapped using single and double digests and cross-hybridisation with the sub-cloned EcoRI and BgIII fragments. Purified fragments and subclones were used as hybridisation probes against chromosomal "Southern" blots to show that at least half of the region has been cloned without alteration. This cannot at present be confirmed for the rest of the region due to the presence of highly repetitive DNA on these cloned fragments. Sequencing data on the 5'-end of the fibroblast IFN-beta gene shows a high density of direct and inverted repeats. The IFN-beta mRNA coding region contains no intron, although the possibility of other transcription starts is not ruled out. The cloned region shows no similarities to known genomic clones containing IFN-alpha genes.

Base Sequence↗

Regulated expression of an introduced MHC H-2K bm1 gene in murine embryonal carcinoma cells.

The transplantation antigens H-2K, H-2D and H-2L are developmentally regulated, highly polymorphic cell surface proteins encoded by the major histocompatibility gene complex (MHC). First detectable on the early embryo, they are subsequently expressed on most somatic cells of the adult mouse in association with the protein beta2-microglobulin (beta 2 M; ref. 5). Cultured F embryonal carcinoma (EC) cells can be induced to differentiate along alternative pathways to form either parietal or visceral9 extra-embryonic endoderm, each concomitant with a change in morphology and pattern of gene expression. Previous reports have demonstrated an increased level of transplantation antigens in differentiated F9 EC cells, but the cell types expressing them were not defined. Here we show that the level of MHC H-2Kb and beta 2 M transcripts is increased during both pathways of this differentiation. Expression of a foreign MHC H-2Kbm1 gene was found to be regulated in a similar manner when the gene was introduced into EC cells. In contrast, an introduced rabbit beta-globin gene was not regulated but expressed constitutively.

Animals↗

Rejection of transplantable AKR leukaemia cells following MHC DNA-mediated cell transformation.

Major histocompatibility complex (MHC) class I molecules can function as specific target antigens in T-cell-mediated cytotoxity. In addition, T cells can kill target cells through non-MHC antigens, for example, virally infected cells, if the target and effector cells express the same MHC class I antigens. Consequently, quantitative and/or qualitative variations in the expression of the H-2/HLA antigens on the target cells could interfere with MHC-restricted immune reactions. We have reported that the AKR leukaemia cell line K36.16, a subline of K36 (ref. 3), on which the H-2Kk antigen cannot be detected, is resistant to T-cell lysis and grows very easily in AKR mice. Other AKR tumour cell lines, like 369, which have a relatively large amount of H-2Kk on their surface, are easily killed by T cells in vitro and require a much larger inoculum to grow in vivo. Monoclonal antibodies against H-2Kk, but not against H-2Dk, prevented the killing by T cells. This suggests that some tumour cells grow in vivo because tumour-associated antigen(s) cannot be recognized efficiently by the host's immune system, due to the absence of MHC molecules which would function as restriction elements for T-cell cytotoxicity. We have tested this hypothesis by introducing the H-2Kk gene into the H-2Kk-deficient AKR tumour cell line K36.16 and have now demonstrated directly the biological relevance of H-2Kk antigen expression in the regulation of the in vivo growth of this tumour cell line.

Animals↗

Increased MHC H-2K gene transcription in cultured mouse embryo cells after adenovirus infection.

The class I major histocompatibility complex (MHC) antigens are highly polymorphic cell-surface proteins whose expression is essential for the cellular immune response against virus-infected, abnormal and foreign cells. Transformation of primary rat cell cultures by the oncogenic adenovirus 12 (Ad12) results in suppression of the transplantation antigens, thus enabling the transformed cells to escape the immune response and efficiently form tumours in vivo. In contrast, transformation of the same cells with the non-oncogenic adenovirus 5 (Ad5) does not suppress the transplantation antigens and, consequently, they elicit an effective (MHC-restricted) immune response. Here, however, we show that infection of mouse embryo cells with both viruses initially increases the level of transcripts from the H-2Kb transplantation antigen gene. Both the adenovirus E1a (12S RNA) and E1b genes are required for activation of the H-2K gene and measurement of the relative rate of transcription indicates that the increase in the level of H-2K messenger RNA following infection is at least in part due to a gene-specific transcriptional activation. The newly transcribed H-2Kb mRNA is then properly transported to the cytoplasm.

Adenoviruses, Human↗