Primitive Immunoglobulins from Ophiocomina Nigra Igkappa Gene when Compared to Human Immunoglobulin Kappa Locus (IPA: Invertebrate Primitive Antibody) in Echinoderms

Immunology of Invertebrates, Orléans University, France

*Corresponding author: Michel Leclerc, Immunology of Invertebrates, Orléans University, France, Tel: 0238410209, Email: [email protected]

Received Date: October 29, 2025

Published Date: November 11, 2025

Citation: Leclerc M. (2025). Primitive Immunoglobulins from Ophiocomina Nigra Igkappa Gene when Compared to Human Immunoglobulin Kappa Locus (IPA: Invertebrate Primitive Antibody) in Echinoderms. Mathews J Immunol Allergy. 9(2):38.

Copyrights: Leclerc M. © (2025).

ABSTRACT

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). From now on we ‘ll speak of Echinoderm primitive Immunoglobulins.

INTRODUCTION

With a great interest we do a comeback on:

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 plasmid [2] 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:

GAGGAACTGCTCAGTTAGGACCCAGACGGAACCATGGAAGCCCCAGCGCAGCTTCTCTTCCTCCTGCTACTCTGGCTCCCAGATACCACTGGAGAAATAGTGATGACGCAGTCTCCAGCCACCCTGTCTGTGTCTCCAGGGGAAAGAGCCACCCTCTCCTGCAGGGCCAGTCAGAGTGTTACCAGCAACTTAGCCTGGTACCAGCAGACACCTGGGCAGTCTCCCAGGCTCGTCATCTATGGTGCATCCAGCAGGGCCAGTGGTGTCCCAGCCAGGTTCAGTGGCAGTGGGTCTGGGACAGAGTTCACTCTCACCATCAGCAGCCTGCAGTCTGAAGATTTTGCAGTTTATTACTGTCAGCAGTATAATAAGTGGCCGCACACTTTTGGCCAGGGGACCAAGCTGGACATCAAACGAACTGTGGCTGCACCATCTGTCTTCATCTTCCCGCCATCTGATGAGCAGTTGAAATCTGGAACTGCCTCTGTTGTGTGCCTGCTGAATAACTTCTATCCCAGGGAGGCCAAAGTACAGTGGAAGGTGGATAACGCCCTCCAATCGGGTAACTCCCAGGAGAGTGTCACAGAGCAGGACAGCAAGGACAGCACCTACAGCCTCAGCAGCACCCTGACGCTGAGCAAAGCAGACTACGAGAAACACAAAGTCTACGCCTGCGAAGTCACCCATCAGGGCCTGAGCTCGCCCGTCACAAAGAGCTTCAACAGGGGAGAGTGTTAGAGGGAGAAGTGCCCCCACCTGCTCCTCAGTTCCAGCCTGACCCCCTCCCATCCTTTGGCCTCTGACCCTTTTTCCACAGGGGACCTACCCCTATTGCGGTCCTCCAGCTCATCTTTCACCTCACCCCCCTCCTCCTCCTTGGCTTTAATTATGCTAATGTTGGAGGAGAATGAATAAATAAAGTGAATCTTTGCAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

RESULTS AND CONCLUSION

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 in constant and variable domains respectivly.

The Sequence of the concerned gene is ID: BC030813.1

At last the Protein GenBank [3] has the following number: AAH30813.1 with 234 amino acids as shown below:

MEAPAQLLFLLLLWLPDTTGEIVMTQSPATLSVSPGERATLSCRASQSVTSNLAWYQQTPGQSPRLVIYGASSRASGVPARFSGSGSGTEFTLTISSLQSEDFAVYYCQQYNKWPHTFGQGTKLDIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQW KVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC

It is shown that an invertebrate Echinoderm (Ophuirid Class) IGKappa gene shares entiere identity with a human immunoglobulin (Figure 1). From now on we have to say Invertebrate Primitive Immunoglobulins about Echinoderms. It is more than “potential Immunoglobulins” from Invertebrates.

Figure 1. 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:

1. Region 1

Region: IgV_L_kappa

Comment: Immunoglobulin (Ig) light chain, kappa type, Variable (V) domain

Location: 22…126

 Common Length 105 aa

2. Region 2

Region: IgC_L

Comment: Immunoglobulin constant domain

Location: 132…231

Common Length 100 aa

REFERENCES

1. Leclerc M, Marie Y, Davoult D, Jolly A, Grange PDL. (2018). A true new gene in ophiocomina nigra: an ophuirid Igkappa gene. J Appl Biotechnol Bioeng. 5(1):17-18.
2. Leclerc M. (2022). Ophuirid Ophiocomina Nigra HLA-E Gene Synthesis in PUC-GW-KAN Plasmid or HLA-E Echinodermata Gene Biosynthesis « De Novo » in E. Coli Sensu Lato Plasmid. J Virol Viral Dis. 2(1):JVVD2200101.
3. Hutchinson AT, Jones DR, McCauley Winter P, Tangye SG, Raison RL. (2014). Cell membrane associated free kappa light chains are found on a subset of tonsil and in vitro-derived plasmablasts. Hum Immunol. 75(9):986-990.