Understanding the Mechanism of Diabetes Mellitus in a LRBA-Deficient Patient

• Published in: Biology (Basel, Switzerland) Vol. 11; no. 4; p. 612
• Main Authors: Hawari, Iman, Ericsson, Johan, Kabeer, Basirudeen Syed Ahamed, Chaussabel, Damien, Alsulaiti, Asma, Sharari, Sanaa A, Maccalli, Cristina, Khan, Faiyaz Ahmad, Hussain, Khalid
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 18-04-2022; MDPI
• Subjects: Autoimmune diseases; Autoimmunity; Beta cells; blood transcriptomics; CD3 antigen; Cell viability; CTLA-4; CTLA-4 protein; Data analysis; Datasets; Diabetes; Diabetes mellitus; Disease; Erythroid cells; Genes; Guardians; Insulin; Insulin secretion; Ionomycin; Lipopolysaccharides; LRBA; Lymphocytes; Lymphocytes T; Mutation; Pancreas; Patients; Phosphatase; Polyclonal antibodies; Proteins; siRNA; Stop codon; Transcriptomics; United States > US; CTLA-4; diabetes mellitus; insulin secretion; autoimmunity; blood transcriptomics; LRBA
• ISSN: 2079-7737; 2079-7737
• DOI: 10.3390/biology11040612

The scope of this study is to show that DM in a LRBA-deficient patient with a stop codon mutation (c.3999 G > A) was not mediated through autoimmunity. We have evaluated the ability of the proband’s T cells to be activated by assessing their CTLA-4 expression. A nonsignificant difference was seen in the CTLA-4 expression on CD3+ T cells compared to the healthy control at basal level and after stimulation with PMA/ionomycin. Blood transcriptomic analysis have shown a remarkable increase in abundance of transcripts related to CD71+ erythroid cells. There were no differences in the expression of modules related to autoimmunity diseases between the proband and pooled healthy controls. In addition, our novel findings show that siRNA knockdown of LRBA in mouse pancreatic β-cells leads reduced cellular proinsulin, insulin and consequently insulin secretion, without change in cell viability in cultured MIN6 cells.