Effects of the NSG-cmah−/− background on human immune cells IGH genes repertoires. a Histograms of IgH CDR3 length (nucleotides) in spleen of NSG-cmah−/− and b NSG mice. c NSG-cmah−/− background was associated with a lower frequency of clonal B-cell expansion in spleen. d After transition from bone marrow to spleen, clonal B-cell expansion increased in NSG- cmah−/− mice. Statistical analysis of CDR3 length was performed immunoSEQ Analyzer (https://www.adaptivebiotech.com/). P < 0.05 was considered a statistically significant. Five animals per strain were used. Individual CDR3 length in spleen (mature compartment) and bone marrow (developmental compartment) are shown on Additional file 2: Figure S2.