Observations on the forward-scattered speckle patterns from healthy human fibroblasts and melanoma cells

Confluent monolayers of Malme-3M (ATCC HTB-64) cells, which is a melanoma cell line, and Malme-3 (ATCC HTB-102) cells, which are normal skin fibroblast cells, were cultured and plated onto glass coverslips. The two lines were isolated from the same patient, providing a tumor and normal counterpart for comparative studies. The forward-scattered objective speckle patterns were observed using a HeNe lasers that emitted at 543 and 633 nm. First and second-order speckle statistics from the two cell types were compared and contrasted. Of particular interest were the mean and maximum speckle size for a given observation geometry, degree of polarization, contrast, and the intensity probability distribution function. The speckle patterns from dry, densely-packed single layer latex sphere samples of various sizes were also investigated for comparison. The results indicate that the far-forward speckle patterns from these confluent monolayers can be used to discriminate between the cell types and can be used to derive specific morphological parameters of the cells.