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Maybe this will answer some questions...
Jino vs. Kexing
Originally posted by WannaImpress:
Jintropin 191 amino acid and Kexing 192?
Well, I'm pretty fond of Jintropin's personally but was doing some research on the Kexings for the fact that they are sligthly cheaper. I have a friend who is pretty knowledgeable in field of rHGH coming from China and told him if he could do some research regarding the top labs out their and below is what he emailed me. Now I'm not saying it's true but certaintly something to think about as it could be accurate.
GENESCIENCE JINTROPIN
Jintropin is the most popular rHGH sold in China. According to IMS, an internationally recognized marketing firm, Jintropin is the absolute market leader in China with just over 75% market share.
Jintropin and Lily's Humatrope use a technology called secretion technology which will produce a 191 amino acid sequence growth hormone, with much less E.coli protein contamination and not any side effects associated with injection, such as red painful welts. This technology also has the advantage that growth hormone produced using secretion technology is very stable; it can be stable at 37C or 98 degrees for about 30 days. While growth hormone with192 amino acid sequence is only stable at room temperature for just a few days.
KEXING FITROPIN
To manufacture their rHGH, Fitropin, Kexing is using a technology called inclusion body technology, which can only produce a 192 amino acid growth hormone, very similar to Genentech's old growth hormone, Protropin. Growth hormone produced by inclusion body technology is very easily contaminated by the E.coli protein used to express the HGH. A very common side effect of this contamination lack of product potency due to degradation of the HGH and painful welts at the injection site.
Kexing's growth hormone's first amino acid is Met, while Jintropin and Lily's Humatrope's first amino acid is Phe (which is identical to natural growth hormone produced in your body). Because Kexing's first amino acid is Met, this indicates clearly that Kexing's growth hormone must have 192 amino acids with met being the extra amino acid.
PLEASE NOTE: all the rHGH manufacturers in China, (Kexing, Anke, United) except for GeneScience use the inclusion body technology.
einstein1905:
That IS good info, and I've has suspicions that Kexing was putting out 192aa GH. However, the reasons stated don't make sense. Producing/purifying any recombinant protein via secretion is simply a function of adding an additional "secretory sequence (usually a sequence from a cytokine) that allows the recombinant protein to be, you guessed it, secreted, so there is far less residual bacterial protein to be reckoned with.
Inclusion body purification is a method where the growth conditions of the bacteria will cause the bacteria to sequester a recombinant protein into "inclusion bodies", which are compartments which can be isolated from the rest of the lysed bacteria and then treated to be lysed themselves, in the absence of the rest of the host proteins.....yet another very efficient method. The number of aa's should have virtually no role in deciding which purification method is used.
If the 191aa sequence is amenable to adding a secretory sequence, then the odds that the 192aa sequence WON'T be are next to nothing. You simply cleave off the secretory sequence after isolating the protein.
That's why I can't understand why anyone would still be making the 192aa analog, as the process should be identical.
I don't recall the EU/mL or residual host protein to GH ratio for Jino, but I'd like to see the numbers for Kexing's. I can't imagine they are really any different.
WannaImpress:
Great info einstein, I wonder if $$$$ plays a role in this? Would it be cheaper to produce a 192 amino instead of a 191 even though the process is pretty much identical as you stated above?
einstein1905:
No cost factor IMO. It's simply a matter of transforming bacteria with the DNA (plasmid) encoding the 192 vs the 191aa. bacterial transformation is a 2hr, $25 job. Once you've got the bacterial strain carrying the DNA encoding either form, all else is identical. It is possible that kexing and ankebio and whomever else may be (allegedly) selling 192aa GH are all just purchasing from a single large supplier (why that company would not have switched is beyond me).
The red welts people get from GH are really indicative of an immune response, and although this certainly could be from residual bacterial protein, it's also very possible that it could be from 192aa GH. the 192aa GH is very dangerous in that antibodies (or an immune response in general) will most likely lead to an autoimmune response against all forms of GH, including endogenous GH.
No matter what's going on, the red welts are indicative of a localized imune response, so even if it is 191aa GH, an upregulated local immune environment can also be very amenable for the development of an immune response to any proteins in the vicinity, in this case 191aa GH, even if, on it's own, it wouldn't elicit a response, in the presence of bacterial protein, it's essentially the same outcome as injecting 192aa GH.
JohnnyB
Kexing is out for me, I won't take a chance that it a 192aa.
Einstein1905
That's the way I feel too. Just the mere fact that I've heard from more than a couple people that they were getting the welts from kexing is enough for me
Jino vs. Kexing
Originally posted by WannaImpress:
Jintropin 191 amino acid and Kexing 192?
Well, I'm pretty fond of Jintropin's personally but was doing some research on the Kexings for the fact that they are sligthly cheaper. I have a friend who is pretty knowledgeable in field of rHGH coming from China and told him if he could do some research regarding the top labs out their and below is what he emailed me. Now I'm not saying it's true but certaintly something to think about as it could be accurate.
GENESCIENCE JINTROPIN
Jintropin is the most popular rHGH sold in China. According to IMS, an internationally recognized marketing firm, Jintropin is the absolute market leader in China with just over 75% market share.
Jintropin and Lily's Humatrope use a technology called secretion technology which will produce a 191 amino acid sequence growth hormone, with much less E.coli protein contamination and not any side effects associated with injection, such as red painful welts. This technology also has the advantage that growth hormone produced using secretion technology is very stable; it can be stable at 37C or 98 degrees for about 30 days. While growth hormone with192 amino acid sequence is only stable at room temperature for just a few days.
KEXING FITROPIN
To manufacture their rHGH, Fitropin, Kexing is using a technology called inclusion body technology, which can only produce a 192 amino acid growth hormone, very similar to Genentech's old growth hormone, Protropin. Growth hormone produced by inclusion body technology is very easily contaminated by the E.coli protein used to express the HGH. A very common side effect of this contamination lack of product potency due to degradation of the HGH and painful welts at the injection site.
Kexing's growth hormone's first amino acid is Met, while Jintropin and Lily's Humatrope's first amino acid is Phe (which is identical to natural growth hormone produced in your body). Because Kexing's first amino acid is Met, this indicates clearly that Kexing's growth hormone must have 192 amino acids with met being the extra amino acid.
PLEASE NOTE: all the rHGH manufacturers in China, (Kexing, Anke, United) except for GeneScience use the inclusion body technology.
einstein1905:
That IS good info, and I've has suspicions that Kexing was putting out 192aa GH. However, the reasons stated don't make sense. Producing/purifying any recombinant protein via secretion is simply a function of adding an additional "secretory sequence (usually a sequence from a cytokine) that allows the recombinant protein to be, you guessed it, secreted, so there is far less residual bacterial protein to be reckoned with.
Inclusion body purification is a method where the growth conditions of the bacteria will cause the bacteria to sequester a recombinant protein into "inclusion bodies", which are compartments which can be isolated from the rest of the lysed bacteria and then treated to be lysed themselves, in the absence of the rest of the host proteins.....yet another very efficient method. The number of aa's should have virtually no role in deciding which purification method is used.
If the 191aa sequence is amenable to adding a secretory sequence, then the odds that the 192aa sequence WON'T be are next to nothing. You simply cleave off the secretory sequence after isolating the protein.
That's why I can't understand why anyone would still be making the 192aa analog, as the process should be identical.
I don't recall the EU/mL or residual host protein to GH ratio for Jino, but I'd like to see the numbers for Kexing's. I can't imagine they are really any different.
WannaImpress:
Great info einstein, I wonder if $$$$ plays a role in this? Would it be cheaper to produce a 192 amino instead of a 191 even though the process is pretty much identical as you stated above?
einstein1905:
No cost factor IMO. It's simply a matter of transforming bacteria with the DNA (plasmid) encoding the 192 vs the 191aa. bacterial transformation is a 2hr, $25 job. Once you've got the bacterial strain carrying the DNA encoding either form, all else is identical. It is possible that kexing and ankebio and whomever else may be (allegedly) selling 192aa GH are all just purchasing from a single large supplier (why that company would not have switched is beyond me).
The red welts people get from GH are really indicative of an immune response, and although this certainly could be from residual bacterial protein, it's also very possible that it could be from 192aa GH. the 192aa GH is very dangerous in that antibodies (or an immune response in general) will most likely lead to an autoimmune response against all forms of GH, including endogenous GH.
No matter what's going on, the red welts are indicative of a localized imune response, so even if it is 191aa GH, an upregulated local immune environment can also be very amenable for the development of an immune response to any proteins in the vicinity, in this case 191aa GH, even if, on it's own, it wouldn't elicit a response, in the presence of bacterial protein, it's essentially the same outcome as injecting 192aa GH.
JohnnyB
Kexing is out for me, I won't take a chance that it a 192aa.
Einstein1905
That's the way I feel too. Just the mere fact that I've heard from more than a couple people that they were getting the welts from kexing is enough for me
