INDIVIDUAL CELL MORPHOLOGY

003003 Cells are reniform (bean-shaped, kidney-shaped). 

003157 Cells are citriform (lemon-shaped, ellipsoidal with 

003147 Cells are ovate, with the ratio of the long axis to 

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Although Sections 3 and 4 deal more specifically with Individual Cell Morphology and Individual Vegetative Cell Size, respectively, there are at least 13 other sections which contain some morphological connotations. An examination of the titles of Sections 5-15, and of the specific items in Sections 36 and 37, is sufficient evidence of this. However, for logical reasons, and for convenience of encoding, we believe that the separation of these sections into broadly related categories is appropriate. 

When embryos treated as described above were left to develop, they reached the onset of gastrulation with no visible changes in morphology compared to untreated embryos. However, as they reached stage 10.5, the embryos underwent rapid and synchronous apoptosis. This rapid cell death had striking morphological characteristics individual cells from the embryo lost their cohesion and adhesiveness and rapidly lysed so that few or no intact cells were found in each embryo 20 minutes following the onset of apoptosis (Fig. IB). 

Many of the morphological and biochemical changes that occur in cells that die by necrosis are very different from those that occur in apoptosis. During necrosis cells swell, mitochondria and endoplasmic reticulum lose their structure and become dysfunctional and the nuclear membrane becomes disrupted (Fig. 35-1). Necrotic death is independent of premitochondrial apoptotic proteins such as Bax, cytochrome c release and caspase activation. Necrosis is further distinguished from apoptosis by the fact that necrosis usually occurs as the result of a traumatic physical injury or stroke and cells die en masse, whereas apoptosis typically occurs in individual cells within a population of surviving neighbors. 

In addition to flow cytometers, cytometric instrumentation has evolved to include Laser Scanning Cytometry (LSC). The LSC is a cross between a flow cytometer and an imaging cytometer. Data are equivalent to the flow cytometer but is slide-based. Endpoints include light scatter and fluorescence, but the instrument can also record position of individual cells on the slide so that cells of interest can be relocated and re-evaluated or photographed. LSC is valuable when cell morphology is important. 

Fig. 11. Scanning electron micrographs (a-d) shown sequential stages in the early part of the adhesion process for mouse fibroblasts from initial contact with a surface to the assumption of a more or less final morphology. The cytoskeleton has the ability to change cell shape quickly and an individual cell may pass from the initial spherical form to the final flattened one in a few minutes. The initial adhesion process at the points of contact between cell and surface is also very rapid but there are subsequent changes at the adhesion sites affecting the nature and strength of the bonds which may continue for many hours. These can be studied by TIRF microscopy...

Figure 11 HCS technology permitted the elimination of false positives - Uninteresting compounds are automatically identified and eliminated by the ArrayScan software as opposed to normal uninhibited (A) or inhibited (B) samples. (C) shows a strong cytotoxic compound that killed the cells. (D) shows a compound that caused cell membrane leakage, which reduced the fluorescence intensity of individual cells and increased the fluorescence background of the well. (E) shows a strong fluorescence compound that cannot be washed away and which caused everything in the well to become fluorescent. (F) is an example of a compound that changed the morphology of cells...

In 1969 Schwartz (S29) described an Albanian family of two children with mild j8-thalassemia major. Their mother had a classical j8-thalassemia heterozygosity, but the father had a normal red cell morphology and normal levels of Hb-A, and Hb-F. The synthesis of /8 chains in this individual was impaired, although to a lesser extent than is usually observed in the classical jS-thalassemia. Interaction of this type of j8-thalassemia with the classical type results in a thalassemia major of reduced severity because the apparent homozygous children from this marriage are only mildly affected with levels of Hb-F of less than 12%. 

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