Papain-treated panels are a simple method for the identification of alloantibodies in multiple myeloma patients treated with anti-CD38-based therapies.

OBJECTIVES: To report our 2 years of experience navigating the interference of anti-CD38 monoclonal antibodies (MAs) in 33 patients and describe papain-treated panels as a complementary method to dithiothreitol (DTT). BACKGROUND: Novel anti-CD38 MAs are now approved or undergoing clinical trials to evaluate their activity in patients with multiple myeloma. A concern with the use of these drugs is that they interfere with blood bank tests in a group of patients who often require blood transfusions. METHODS: Clinical data and whole blood samples were collected from patients receiving daratumumab or isatuximab. Routine blood bank serological tests were performed. RESULTS: A total of 9·1% of patients presented with alloantibodies prior to treatment. All patients exhibited nonspecific reactivity in indirect antiglobulin tests, and 26% had positive direct antiglobulin tests after beginning treatment. This interference disappeared in all patients after discontinuing treatment. Papain panels avoided this reactivity and allowed us to identify alloantibodies. Phenotyped blood units were transfused, and no patient suffered any transfusion-related complications. CONCLUSION: Anti-CD38 MAs produce nonspecific interference in blood bank tests. This interference can be overcome by various methods, including DTT or papain treatment as proposed here. These methods have limitations that can be resolved using phenotyped blood units.

Effects of early overnutrition on the renal response to Ang II and expression of RAAS components in rat renal tissue.

BACKGROUND AND AIMS: The aim of this study was to analyze the effects of early overnutrition (EON) on the expression of the renin angiotensin aldosterone system (RAAS) components in renal cortex, renal arteries and renal perivascular adipose tissue (PVAT), as well as the vascular response of renal arteries to Angiotensin II (Ang II). METHODS AND RESULTS: On birth day litters were adjusted to twelve (L12-control) or three (L3-overfed) pups per mother. Half of the animals were sacrificed at weaning (21 days old) and the other half at 5 months of age. Ang II-induced vasoconstriction of renal artery segments increased in young overfed rats and decreased in adult overfed rats. EON decreased the gene expression of angiotensinogen (Agt), Ang II receptors AT1 and AT2 and eNOS in renal arteries of young rats, while it increased the mRNA levels of AT-2 and ET-1 in adult rats. In renal PVAT EON up-regulated the gene expression of COX-2 and TNF-α in young rats and the mRNA levels of renin receptor both in young and in adult rats. On the contrary, Ang II receptors mRNA levels were downregulated at both ages. Renal cortex of overfed rats showed increased gene expression of Agt in adult rats and of AT1 in young rats. However the mRNA levels of AT1 were decreased in the renal cortex of overfed adult rats. CONCLUSION: EON is associated with alterations in the vascular response of renal arteries to Ang II and changes in the gene expression of RAAS components in renal tissue.