Specific granule deficiency

Specific-granule deficiency is a very rare neutrophil defect that has only been described in five patients worldwide. Patients present with recurrent 

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Neutrophil-Specific Granule Deficiency. In this rare disorder, secondary or specific granules in neutrophils are absent. The defect may arise from a mutation that leads to the loss of function of the transcription factor CCAAT/enhancer binding protein e (C/EBPe), which is needed for neutrophil response to inflammation (91). Specific granule deficiency affecfs fhe migration of neutrophils. 

Patients with thermal injury are also deficient in specific granules. In this case, however, it appears that this deficit is due to activation of the cells such that they discharge their specific granules. Neutrophils from patients with bums have an increased expression of plasma-membrane markers (as would be predicted if specific-granule membranes have fused with the plasma membrane), and serum levels of lysozyme and lactoferrin are elevated. These patients have impaired chemotaxis and defective oxygen metabolism. 

It is not clear what specific functions the starch synthase isoforms may have in synthesis of the starch granule. There has been considerable effort to isolate mutant plants specifically deficient in one of the isoforms of the starch synthase in order to determine their individual functions. These have provided some insight into the possible... 

MMP-8 and MMP-9 are stored in the granules of polymorphonuclear leukocytes. These cells are key effectors in inflammatory and infectious processes. A role for these MMPs in shock is supported by studies in MMP-9 deficient mice that were shown to be resistant to endotoxic shock. Dubois et al. (D4) proposed that specific MMP-9 inhibition constitutes a potential approach for the treatment of septic shock syndromes. 

Cytoplasmic granulations can be revealed by specific coloration techniques. They are insoluble reserve substances of an organic nature polymers of glucose or of the polyester of j6-hydroxybutyric acid. These reserve substances accumulate in the event of a nitrogen deficiency, when a source of carbon is still present. Inclusions of volutin (a polymer of insoluble, inorganic phosphate) are characteristic in lactic acid bacteria, especially certain species of the genus of strictly homofermenta-tive Lactobacillus. Volutin comprises a phosphate reserve available for the synthesis of phosphory-lated molecules such as nucleic acids. 

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