Brief Report Volume 10 Issue 1
Immunology of Invertebrates, Orléans University, France
Correspondence: Michel Leclerc, Immunology of Invertebrates, Div: Biochem/Biology, Orléans University, 556 rue Isabelle Romée, 45640 Sandillon, France
Received: October 31, 2025 | Published: December 18, 2025
Citation: Leclerc M. Primitive immunoglobulins from ophiocomina nigra igkappa gene when compared to human immunoglobulin kappa locus bioinformatic data. J Stem Cell Res Ther. 2025;10(1):249-250 DOI: 10.15406/jsrt.2025.10.00212
Entiere identities between Invertebrate Ophiocomina nigra IGKappa gene and Human IGK gene are confirmed, in the present work, at the level of immunoglobulin domains (constant and variable) and by informatic technology. From now on we ‘ll speak of Echinoderm primitive Immunoglobulins.
Keywords: immunogoblins, clone, sequence
The transcriptome of the Ophuirid : Ophiocomina nigra IGKappa gene which has been discovered recently.1 Since it was synthesized de novo and cloned in a pUC-GW-Kan plasmid2 which was a gift of Bo Huang laboratories+.
The original sequence of the Ophuirid IGKappa gene, after cloning, was the following in 5’-3’
Original sequence
GAGGAACTGCTCAGTTAGGACCCAGACGGAACCATGGAAGCCCCAGCGCAGCTTCTCTTCCTCCTGCT
ACTCTGGCTCCCAGATACCACTGGAGAAATAGTGATGACGCAGTCTCCAGCCACCCTGTCTGTGTCTCCA
GGGGAAAGAGCCACCCTCTCCTGCAGGGCCAGTCAGAGTGTTACCAGCAACTTAGCCTGGTACCAGCAG
ACACCTGGGCAGTCTCCCAGGCTCGTCATCTATGGTGCATCCAGCAGGGCCAGTGGTGTCCCAGCCAGGTT
CAGTGGCAGTGGGTCTGGGACAGAGTTCACTCTCACCATCAGCAGCCTGCAGTCTGAAGATTTTGCAGTTTATT
ACTGTCAGCAGTATAATAAGTGGCCGCACACTTTTGGCCAGGGGACCAAGCTGGACATCAAACGAACTGTGG
CTGCACCATCTGTCTTCATCTTCCCGCCATCTGATGAGCAGTTGAAATCTGGAACTGCCTCTGTTGTGTGCCTGC
TGAATAACTTCTATCCCAGGGAGGCCAAAGTACAGTGGAAGGTGGATAACGCCCTCCAATCGGGTAACTCCC
AGGAGAGTGTCACAGAGCAGGACAGCAAGGACAGCACCTACAGCCTCAGCAGCACCCTGACGCTGAGCAAAG
CAGACTACGAGAAACACAAAGTCTACGCCTGCGAAGTCACCCATCAGGGCCTGAGCTCGCCCGTCACAAAGAG
CTTCAACAGGGGAGAGTGTTAGAGGGAGAAGTGCCCCCACCTGCTCCTCAGTTCCAGCCTGACCCCCTCCCATC
CTTTGGCCTCTGACCCTTTTTCCACAGGGGACCTACCCCTATTGCGGTCCTCCAGCTCATCTTTCACCTCACCCC
CCTCCTCCTCCTTGGCTTTAATTATGCTAATGTTGGAGGAGAATGAATAAATAAAGTGAATCTTTGCAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAA
The original gene, the original protein issued from this last one share total identity with Homo sapiens immunoglobulin kappa locus, mRNA (cDNA clone MGC:22645 IMAGE:4700961): they have a complete identity (Figure 1) and share nearly 100 AA common, in constant and variable domains respectively.
The sequence of the concerned gene is ID: BC030813.1
At last the Protein GenBank3 has the following number: AAH30813.1 with 234 amino acids as shown below:
MEAPAQLLFLLLLWLPDTTGEIVMTQSPATLSVSPGERATLSCRASQSVTSNLAWYQQTPGQSPRL
VIYGASSRASGVPARFSGSGSGTEFTLTISSLQSEDFAVYYCQQYNKWPHTFGQGTKLDIKRTVAAPS
VFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQW KVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC
It is shown in conclusion, that an invertebrate Echinoderm (Ophuirid Class) IGKappa gene shares entire identity with a human immunoglobulin IGK (Figure 1). From now on we have to think of: Invertebrate Primitive Immunoglobulin’s about Echinoderms as it is said about IPA (Invertebrate Primitive Antibody) also in Echinoderms. We have not yet the three-dimensional structure of this protein. On the other hand we have the sea star one which is, in a certain manner its “sister” in the genealogic tree.4
In fact, compared sequencing of Human IGK and Ophiocomina nigra IGKappa gene present more 90% in similarities as shown in Figure 1.
In the present time, we don’t know the evolutionary process which leads from Echinoderms to Man, in matter of Immunoglobulin “Immunology”. If there is an evolution in this process, many steps are requested to explain such a phenomenon, which appears, nevertheless, so suddenly, with also, MHC genes, CDR1, CDR2, CDR3 region? In the Invertebrate Primitive Antibody.4
+ We thank greatly Bo Huang Laboratories
IGK@ protein [Homo sapiens] graphic (in dark) by NCBI (https://www.ncbi.nlm.nih.gov/protein/AAH30813.1?report=graph) shares IG domains with Ophiocomina nigra IGKappa protein (in grey) issued from ophuirid IGKappa gene
GenBank: AAH30813.1 protein issued from IGK gene has two immunoglobulin domains:
Region 1
Region: IgV_L_kappa
Comment: Immunoglobulin (Ig) light chain, kappa type, Variable (V) domain
Location: 22…126
Common Length 105 aa
Region 2
Region: IgC_L
Comment : Immunoglobulin constant domain
Location : 132…231
Common Length 100 aa
None.
The author declares that there are no conflicts of interest.
©2025 Leclerc. This is an open access article distributed under the terms of the, which permits unrestricted use, distribution, and build upon your work non-commercially.