PubMed Health⌕ Search

Biomedical subjects

K F Milde

Publications and source records attributed to K F Milde.

7 recordsLinked to original sources
PubMed1999

CD44 splice variants in draining lymph nodes precede allograft rejection of endocrine cells.

Upon allogeneic transplantation (Tx) of pancreatic islets under the kidney capsule of diabetic rats, cells from draining lymph nodes and, to a minor degree, bone marrow transiently upregulate CD44 splice variants as detected by RT-PCR using CD44 variant exon specific primers. Maximal expression was on day 5 post Tx in lymph nodes and thus precedes islet rejection sufficiently (in this model by 5 days) to still permit establishing rescue by immunosuppressive therapy. CD44 variant exon sequence could therefore serve as early markers of allograft rejection.

Alternative Splicing↗
PubMed1996

Expression of a specific subset of CD44 variant transcripts in NOD pancreatic islets.

Adhesion of lymphocytes to the endothelial venules inside the islets of Langerhans seems to initiate the infiltration of islets in NOD mice. An overexpression of the lymphocyte surface molecule CD44 in infiltrated NOD islets compared with peripheral blood lymphocytes was recently reported. The CD44 protein family includes a variety of molecules generated by alternative RNA splicing from 10 variant exons (v1-v10). By using reverse transcriptase-polymerase chain reaction followed by Southern blotting and hybridization to exon-specific cDNA probes, we investigated the expression of CD44 isoforms in highly purified islets of Langerhans from 4- and 10-week-old NOD mice. At least six CD44 isoforms were strongly overexpressed in NOD islets at 4 and 10 weeks when compared with age-matched BALB/c islets. Controls in different tissues indicate that these variants are specifically increased in the islets from the NOD strain. Islets from the NOD-scid/scid strain also expressed these variant exons. Splenocytes from BALB/c did not express CD44 isoforms, whereas splenocytes from 4-week-old NOD mice did express CD44 variants. Treatment with inflammatory mediators induced new isoforms; however, these transcripts have a different variant exon composition from that found in NOD mice islets. These results suggest that some isoforms are expressed very early in the development of insulitis by a component of the NOD islet itself and underscore a possible role of CD44 in islet infiltration.

Animals↗
PubMed1994

Molecular cloning of the canine CD44 antigen cDNA.

Molecular cloning of the dog homologue of the human CD44 was achieved using RT/PCR. A 1055 bp cDNA has a deduced amino acid sequence of 351 residues, 338 of them correspond to the mature protein. Nine conserved cysteine residues were found. The extracellular region contains a single link superfamily domain on the N-terminal part and potential post-translational modification sites as: N- and O-linked glycosylation sites and chondroitin sulfate attachment sites. Three mRNAs of 2.2, 3.8 and 4.4 kb were identified on Northern blot analysis and Western blot hybridization revealed a 85-90 kDa protein expressed in lymph node tissue.

Amino Acid Sequence↗
PubMed1994

Expression of CD44 variant transcripts in dog lymphatic tissue.

The gene of the CD44 cell surface glycoprotein consists of 20 exons. Ten exons known as variant exons are inserted by alternative RNA splicing between exon 5 and 16, thus generating diversity in the extracellular portion of the protein. We have cloned the dog cDNA homologue of the human variant exon region of CD44 and characterized its transcript expression in normal lymphatic tissues. Using PCR with primers complementary to regions contiguous to the insertion point and a variant exon, all ten variant exons of dog CD44 were detected in a high number of different isoforms. Transcripts containing the ten variable exons directly spliced to both sides of the insertion point were detected. We found an extensive usage of all variant exons from v1 to v10 in a high number of different combinations, some presenting a tissue-specific expression pattern. A similar complex profile of transcript expression was found in peripheral blood lymphocytes from rat and human.

Amino Acid Sequence↗
PubMed1993

Primary structure of the canine CD4 antigen.

After PCR amplification two overlapping cDNA clones encoding the dog homologue of the human CD4 glycoprotein were identified. This internal fragment of the mature protein including the complete extracellular domains, consists of 1297 bp with a deduced amino acid sequence of 432 residues. The dog CD4 molecule differs from the corresponding protein of other species including human in the second domain. We found nine extra residues in the beginning of that domain, a cysteine at position 138, usually involved in a disulfide bridge, is substituted by tryptophan, and three new glycosylation sites are present.

Amino Acid Sequence↗