Comparative Cellular Localization of Sugar Residues in Bull (Bos taurus) and Donkey (Equus asinus) Testes Using Lectin Histochemistry

Abstract

Lectins are glycoproteins of a non-immune origin often used as histochemical reagents to study the distribution of glycoconjugates in different types of tissues. In this study, we performed a comparative cellular localization of sugar residues in bull and donkey testes using immunofluorescent lectin histochemistry. We inspected the cellular localization of the glycoconjugates within the testes using 11 biotin-labeled lectins (LCA, ConA, PNA, WGA, DBA, SBA, ECA, BPL, PTL-II, UEA-1, and PHA-E4) classified under six groups. Although the basic testicular structure in both species was similar, the cellular components showed different lectin localization patterns. The statistical analysis revealed no significant association between the intensity of labeling and different variables, including group and type of lectin and type of cell examined, at p < 0.05. However, a stronger response tended to occur in the donkey than in the bull testes (odds ratio: 1.3). These findings may be associated with the different cellular compositions of the glycoproteins and modification changes during spermatogenesis. Moreover, glycoconjugate profiling through lectin histochemistry can characterize some cell-type selective markers that will be helpful in studying bull and donkey spermatogenesis.

Differential cellular localization of lectins in the testes of dromedary camel (Camelus dromedarius) during active and inactive breeding seasons

“…The lectin histochemistry is attributed to revealing certain epitopes on the glycan chains of cellular glycoconjugates [ 30 , 53 , 54 ] that may give the sugar residues the ability to store biological data. Additionally, the importance of lectin histochemistry includes using lectin-specific markers in cytochemistry and histochemistry, purifying reactive sugar receptors, designing selective high-affinity ligands of glycoconjugates, and aiming to make long-term participation in structure-function relationships at the level of cells, molecules, organs, and tissues [ 53 , 55 ].…”

“…LHC was conducted according to MS Gewaily, M Kassab, A Aboelnour, EA Almadaly and AE Noreldin [ 30 ]. Briefly, the sections were deparaffinized and rehydrated till saturated with distilled water.…”

“…Cellular glycoconjugates depend on interactions between carbohydrates and proteins indicating the oligosaccharides importance [ 24 , 25 ]. The sugar codes express the biological information and the glycan epitopes transmission [ 26 – 30 ].…”

“…Furthermore, many reports have confirmed that cellular glycoconjugates have pivotal functions such as motility, development, and growth regulation [ 41 – 43 ]. Many studies have revealed various modulations in the sugar residues within the spermatocytes that differ between species such as some domesticated mammals [ 30 , 44 – 46 ], rodents [ 47 , 48 ], and humans [ 49 ].…”

Cell-Surface Glycan Labeling and Sensing

“…Lectins, a group of proteins produced by animal and plant cells, exhibit specific saccharide-binding abilities without invoking an immune response [15][16][17]. Researchers usually use lectins to isolate and purify glycoproteins [18,19], to identify glycoforms [20][21][22][23][24][25][26], or to regulate the differentiation [27] and maturation [28] of cells, etc. The affinity of lectins towards glycans is generally in the micromolar range due to the shallow binding pocket on the lectin surface exposed to competing solvent interactions [29].…”