Background Knockout of either toll-like receptor 4 (TLR4) or 2 (TLR2) had been reported to delay the Wallerian degeneration after peripheral nerve injury by deterring the recruitment of the macrophages and clearance of myelin debris. 10 after crush injury were subjected to semi-thin section and toluidine blue stain for a quantitative histomorphometric analysis. With less remyelinated nerves and more nerve debris the histomorphometric analysis revealed a worse nerve regeneration following the sciatic nerve crush injury in both and mice than the C57BL/6 mice. Although there was a delayed expression of Sox10 but not Oct6 during remyelination with an average 4-day delay in the demyelination process the subsequent complete formation of Mpz during remyelination was also delayed for 4?days implying that this impaired nerve regeneration was mainly attributed to the delayed demyelination process. Conclusions Both TLR4 and TLR2 are crucial for nerve SPRY1 regeneration after nerve crush injury mainly by delaying the demyelination but not the remyelination process. and mice had a reduced recruitment of macrophages persisted myelin debris in the distal nerve stump and a significant delay of the process of Wallerian degeneration during the nerve regeneration process . In this study we are interesting in investigating the impact of the knockout of TLR2 or TLR4 gene around the nerve regeneration regarding the process of demyelination as well as remyelination. Therefore the BIIB-024 quantitative histomorphometric assessment of peripheral nerve architecture with detection of the time-dependent expression of Mpz Sox10 Oct6 proteins in and wild type mice in a sciatic nerve crush injury were investigated in this study to answer the question. Methods Animals Eight to twelve weeks old male mice weighing 20-30?g were used. (B6.B10ScN-n?=?6 n?=?6 and C57BL/6 n?=?5) and sham-operated (C57BL/6 n?=?6) groups were re-anesthetized for harvesting the studied nerve and then sacrificed at specific time point around the postoperative day 10. The axial one centimeter of nerve distal to the injured site was isolated BIIB-024 and fixed at 4°C with 3% glutaraldehyde (Polysciences Inc. Warrington PA USA) washed in 0.1?M phosphate buffer (pH?7.2) post-fixed with 1% osmium tetroxide (Fisher Scientific Pttisburgh PA USA) dehydrated in graded ethanol solutions and embedded in BIIB-024 Araldite 502 (Polysciences Inc.). Axial semithin sections 1 thick at a 5-mm distance from the injured site were stained with 1% toluidine blue for histomorphometric analysis. We use a binary image analysis for multicomponent analysis of peripheral nerve histomorphometry  by an observer blinded to experimental group. Total myelinated fiber counts were measured based on six representative fields at 1000 magnification. Fiber count fiber width fiber area total fiber area fiber debris area myelin area axon area and axon width were calculated and analyzed. Statistical analysis All the results were presented as mean?±?standard error. An overall analysis of the BIIB-024 differences between group means was calculated by one way analysis of variance (ANOVA). A post hoc Fisher’s least significant difference test was used to compare the difference between groups. In all cases statistical significant was set at P?0.05. Results Quantitative histomorphometric analysis The axial section of the nerve 5?mm distal to the injured site in four mice groups (C57BL/6-sham C57BL/6-crush mice the specimens presented significant prominent debris with less percentage nerve tissue. At day 10 the fiber count fiber width fiber area total fiber area fiber debris area myelin area axon area and axon width in both the (P?0.05) group (and mice were significantly larger than C57BL/6 mice. Physique 1 Representative histological sections (X1000) taken distal to the nerve crush injury site around the postoperative day 10 and stained with toludine blue. Nerve specimens were from sham-operated C57BL/6 mice as well as C57BL/6 and mice the Mpz level had a significant decrease since day 7 to day 17 with a delayed recovery in day 21. Put all together knockout of toll-like receptor 4 or 2 signaling would contribute to the timing delay of around 4?days for the formation of the myelin structure protein. The Oct6 level (Physique?3) of C57BL/6 mice started to increase BIIB-024 significantly since postoperative day 3. In and mice.