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Antibody-modified gold nanomaterials are central to many novel biosensing technologies for example the lateral flow assays technology. The combination of the specificity, provided by antibody-antigen interactions, and the unique optical properties of nanomaterials provide excellent properties for biosensors. Here, we present the use of gold nanorods (GNR) with the localized Surface Plasmon Resonance (LSPR) peak in the visible range for biomarker detection. The colour of the GNR can be tuned by the reaction conditions to provide multi-coloured gold nanorod conjugates. These antibody functionalized GNR have the potential to provide significant improvements in multiplexed analysis and sensitivity compared to conventional gold nanoparticle based lateral flow assays. However, a major challenge is the synthesis of stable conjugates that resist aggregation in samples with high ionic strength, (e.g. salt solutions) and allow highly sensitive detection of proteins. A detailed investigation of different reagents for the functionalization of gold nanorod materials are reported. An antibody modified GNR based lateral flow assay is validated for the determination of C-reactive Protein (CRP)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The precise arrangement of B- and T-lymphocytes in the different compartments of the human splenic white pulp is still largely unknown. We therefore performed a 3D reconstruction of 150 serial sections of a representative adult human spleen alternately stained for CD3 and CD20. The results indicate that the T-cell regions of human spleens may be interrupted by B-cell follicles. Therefore, there is no continuous periarteriolar lymphatic T-cell sheath (PALS) around white pulp arterioles. An arteriole may be surrounded by T-lymphocytes at one level, then run across a follicle without any T-cells around, and finally re-enter a T-cell region. T- and B-cell compartments are intricately interdigitated in the human splenic white pulp. CD4(+) T-lymphocytes and the typical fibroblasts of the T-cell region may extend as a thin shell at the follicular surface within the marginal zone. On the other hand, IgD(++) B-cells continue from the follicular outer marginal zone along the surface of the T-cell region. Our findings indicate that the microanatomy of the splenic white pulp differs between humans and rodents. This may have consequences for the immigration of recirculating lymphocytes and for initial interactions among antigen-specific T- and B-lymphocytes.